Updated on 2024/02/13

写真a

 
SOMURA Hiroaki
 
Organization
Faculty of Environmental, Life, Natural Science and Technology Associate Professor
Position
Associate Professor
External link

Degree

  • 博士(農学) ( 東京農工大学 )

Research Interests

  • Irrigation and Drainage

  • Water Quality

  • Watershed Management

  • Rural Engineering

  • 水文学

  • Hydrology

Research Areas

  • Environmental Science/Agriculture Science / Rural environmental engineering and planning

Research History

  • Okayama University   環境生命科学研究科(農村環境創成学講座)   Associate Professor

    2018.4

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  • Shimane University   Faculty of Life and Environmental Science   Associate Professor

    2010.7 - 2018.3

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  • 日本学術振興会優秀若手研究者海外派遣事業(Texas A&M University System,Texas A&M AgriLife Research-Blackland Research & Extension Center)   客員研究員

    2010.4 - 2011.3

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  • Shimane University   Faculty of Life and Environmental Science   Assistant Professor

    2007.4 - 2010.6

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  • Shimane University   Faculty of Life and Environmental Science   Research Assistant

    2005.3 - 2007.3

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  • (独)農業工学研究所   特別研究員

    2003.4 - 2005.2

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Papers

  • Evaluation of drought features in the Dakbla watershed, Central Highlands of Vietnam Reviewed International coauthorship International journal

    Vo Ngoc Quynh Tram, Hiroaki Somura, Toshitsugu Moroizumi

    Hydrological Research Letters   15 ( 3 )   77 - 83   2021.9

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)  

    DOI: 10.3178/hrl.15.77

    DOI: 10.3178/hrl.15.77

  • Environmental flow sustainability in the Lower Limpopo River Basin, Mozambique Reviewed International coauthorship International journal

    Osvaldo Silva Zefanias Nhassengo, Hiroaki Somura, June Wolfe III

    Journal of Hydrology: Regional Studies   36   100843   2021.8

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier  

    DOI: 10.1016/j.ejrh.2021.

  • The Impacts of Land-Use Input Conditions on Flow and Sediment Discharge in the Dakbla Watershed, Central Highlands of Vietnam Reviewed International journal

    Vo Ngoc Quynh Tram, Hiroaki Somura, Toshitsugu Moroizumi

    Water   13 ( 5 )   627   2021.2

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:MDPI  

    DOI: 10.3390/w13050627

  • Phosphorus Release from Agricultural Drainage Sediments with Iron-Added Sediment Microbial Fuel Cells Reviewed International journal

    Perera GLEP, Maeda M, Akao S, Somura H, Nakano C, Nishina Y

    Journal of Water and Environment Technology   2024.1

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  • Efficient agricultural monitoring: a methodology for assessing individual farmer adherence to rice planting schedule for tertiary irrigation system in the Muda Irrigation Scheme using Earth observation datasets Reviewed International journal

    Aliya Binti Mhd Zahir, Hiroaki Somura, Toshitsugu Moroizumi

    Hydrological Research Letters   2024

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

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  • Iron-Added Sediment Microbial Fuel Cells to Suppress Phosphorus Release from Sediment in an Agricultural Drainage Reviewed International journal

    Gamamada Liyanage Erandi Priyangika Perera, Morihiro Maeda, Hiroaki Somura, Chiyu Nakano, Yuta Nishina

    Journal of Water and Environment Technology   21 ( 5 )   237 - 248   2023.10

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    Phosphorus (P) release from sediment caused eutrophication in Kojima Lake, Japan. The efficiency of iron-added sediment microbial fuel cells (SMFCs) in regulating P release from agricultural drainage sediment was investigated in this study. Surface sediment collected from an agricultural drainage canal flowing into Kojima Lake was mixed with iron oxide (Fe2O3) or amorphous iron oxyhydroxide (FeOOH) at 50 mmol kg−1. A 14.6-cm high acrylic pipe was filled with 80 mL of deionized water after 130 g of sediment was placed. A 3 x 3 cm graphite felt was used for the anode in a dual chamber SMFC, while a carbon rod was used for the cathode. Three treatments: No Fe, Fe2O3, and FeOOH, were operated for 408 h under open or closed circuit conditions. Results showed that FeOOH addition lowered P release from sediment regardless of SMFC operational conditions, suggesting that higher P adsorption by FeOOH may mask the effect of SMFCs. Fe2O3 did not reduce total P concentration in the overlying water. In addition, electricity generation was not enhanced by Fe-added SMFCs. Although SMFCs increased sedimentary redox potential, P release was not suppressed by the SMFC operation, indicating that organic P would be released by SMFCs from P-rich sediment.

    DOI: 10.2965/JWET.23-040

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  • Effects of oxidation treatment of biochars derived from different raw materials and pyrolysis temperatures on nitrous oxide emission from soil Reviewed

    Yuki Masukura, Morihiro Maeda, Chiyu Nakano, Hiroaki Somura, Shinzo Yamane, Yuta Nishina

    Japanese Journal of Soil Science and Plant Nutrition   94 ( 4 )   245 - 253   2023.8

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.20710/dojo.94.4_245

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  • Mercury pollution in the soil and river water of the Ratai watershed by artisanal and small-scale gold mining activities in Pesawaran District, Lampung, Indonesia Reviewed International coauthorship International journal

    Slamet Budi Yuwono, Irwan Sukri Banuwa, Nano Suryono, Hiroaki Somura, Dermiyati

    Journal of Degraded and Mining Lands Management   10 ( 2 )   4233 - 4243   2023.1

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    Language:English   Publishing type:Research paper (scientific journal)  

    The high risk of mercury pollution in the Ratai watershed due to artisanal and small-scale gold mine activities in Pesawaran District, Lampung, Indonesia, was evaluated. Studies are needed to improve the understanding of the effect of heavy metal pollution, especially mercury (Hg), in soil and river water along the watershed because of erosion. The Universal Soil Loss Equation (USLE) integrated with Geographic Information Systems (GIS) model was used to analyze the transport of mercury (Hg) from nonpoint source pollution loads to the Way Ratai River using rainfall-based erosion. Soils and river water samplings were conducted in 2020. Biophysical conditions, the land cover, and the rainfall data of the Ratai watershed were also taken into account. The results indicated that Hg concentrations in the soil and the river water were high, ranging from 0.26-28.9 mg L-1 and from 0.08-14.1 mg L-1, respectively. The reason for the high Hg contents in the soils and the river waters was the high erosion rate in the watershed. As the study area was characterized by high rainfall erosivity and low to high soil erodibility, the erosion-caused Hg contamination in soil and water can be significant if no conservation strategies are developed.

    DOI: 10.15243/jdmlm.2023.102.4233

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  • Greenhouse gas emissions from agricultural soil amended with kitchen compost of varying ages Reviewed International journal

    Tran Thi Minh Chau, Takashi Someya, Satoshi Akao, Masato Nakamura, Fumiko Oritate, Hiroaki Somura, Shinzo Yamane, Morihiro Maeda

    Soil Science and Plant Nutrition   69 ( 2 )   137 - 147   2023.1

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    Although the use of kitchen waste compost is very common, GHG emissions from soil amended with kitchen waste compost have not been studied. This study aimed to determine the effects of kitchen compost age and application rates on GHG emissions to identify optimal compost management. Soil samples mixed with kitchen waste compost at three different ages: 1 month (1M), 2 months (2M), and 3 months (3M) at two application rates (1% and 2% w/w) were incubated at 25°C for 28 days under aerobic conditions. Emissions of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) were determined on days 3, 7, 14, 21, and 28. Results showed that N2O and CO2 emissions decreased with compost age (p < 0.05). Increased application rates of compost led to increased CO2 emissions and suppression of N2O emissions. Furthermore, CH4 was emitted from soil amended with kitchen compost even under aerobic conditions. This study suggests that 3M kitchen waste compost is optimal in terms of GHG emissions upon application to soil under aerobic conditions.

    DOI: 10.1080/00380768.2022.2160622

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  • Effects of local land-use policies and anthropogenic activities on water quality in the upstream Sesan River Basin, Vietnam Reviewed International coauthorship International journal

    Vo Ngoc Quynh Tram, Hiroaki Somura, Toshitsugu Moroizumi, Morihiro Maeda

    Journal of Hydrology: Regional Studies   44   101225 - 101225   2022.12

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.ejrh.2022.101225

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  • Artificial macropores and water management effects on reduction of greenhouse gas emissions from rice paddy fields Reviewed

    Thanh Long Bui, Yasushi Mori, Morihiro Maeda, Hiroaki Somura

    Environmental Challenges   9   100657 - 100657   2022.12

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    Rice production is an important sector of global agriculture, sustaining more than half of the world's population. However, rice production contributes significantly to global warming through increased emission of greenhouse gasses (GHGs), primarily CH4, into the atmosphere. Therefore, this study examined countermeasures to reduce GHG emissions from paddy fields without affecting rice production. A column experiment was conducted to investigate the effects of soil macroporous structure and water management on GHG emissions from flooded alluvial clay soil (paddy soil). The soils were subjected to different management regimes: with and without artificial macropores, compost, and drainage treatment. Drainage was maintained at 6.5 mm d −1 to ensure infiltration yet prevent excessive leakage from the paddy field. The measured parameters included GHG emissions, soil water content, redox potential, soil temperature, soil swelling, total carbon, total nitrogen, iron, and manganese. The results showed that the soil column with macropores and drainage had significantly lower CO2 and CH4 emissions than that without macropores and drainage. In addition, the soil level increment, and thus, the amount of gas (CH4) produced in the soil column with drainage were lower than that without drainage. The combination of drainage treatment and macropores might have effectively acted as a hydrodynamic gradient and a structure that promotes freshwater intrusion into deeper soil profiles, inhibiting absolute anaerobic methanogenic activity. The redox potential of the column with drainage and macropores was the highest. Moreover, CO2 and CH4 emissions were reduced at a relatively small drainage rate of 6.5 mm d −1 by adding macropores to the soil. The findings confirmed that GHG emissions were effectively reduced by a porous soil structure at a low drainage rate. Macropore application also exhibited effectiveness at mitigating nutrient loss (TOC and TN) through the drainage. Therefore, low tillage before flooding would be preferable to conserve the macroporous structure. However, the results also highlight an adverse effect on mineral leaching (particularly Mn) through the column with macropores.

    DOI: 10.1016/j.envc.2022.100657

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  • Nitrous oxide and carbon dioxide emissions from two types of soil amended with manure compost at different ammonium nitrogen rates Reviewed International journal

    Thanuja Deepani Panangala Liyanage, Morihiro Maeda, Hiroaki Somura, Makito Mori, Taku Fujiwara

    Soil Science and Plant Nutrition   68 ( 4 )   473 - 490   2022.7

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Informa UK Limited  

    DOI: 10.1080/00380768.2022.2087198

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  • Nitrous oxide and carbon dioxide emissions from two soils amended with different manure composts in aerobic incubation tests Reviewed International journal

    Thanuja Deepani Panangala Liyanage, Morihiro Maeda, Hiroaki Somura, Nguyen Thi Thu Thuong, Makito Mori, Taku Fujiwara

    Soil Science and Plant Nutrition   68 ( 4 )   491 - 504   2022.7

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Informa UK Limited  

    DOI: 10.1080/00380768.2022.2095669

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  • Simulation of rice paddy systems in SWAT: A review of previous applications and proposed SWAT+ rice paddy module Reviewed International coauthorship International journal

    Philip W. Gassman, Jaehak Jeong, Julien Boulange, Balaji Narasimhan, Tasuku Kato, Hiroaki Somura, Hirozumi Watanabe, Sadao Eguchi, Yuanlai Cui, Atsushi Sakaguchi, Le Hoang Tu, Rui Jiang, Min-Kyeong Kim&Jeffrey G. Arnold, Wei Ouyang

    International Journal of Agricultural and Biological Engineering   15 ( 1 )   1 - 24   2022

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:International Journal of Agricultural and Biological Engineering (IJABE)  

    The Soil and Water Assessment Tool (SWAT) is an ecohydrological watershed-scale model which was initially developed in the early 1990s to simulate the impacts of land use, management systems, and climate on hydrology and/or water quality. First adopted in the U.S., the use of the model then spread to Europe and then later to Asia and other regions. The range of applications that SWAT has been applied to have also expanded dramatically, which influenced ongoing model development which has been virtually continuous over the past two decades. A key component of many SWAT applications in Asia is accounting for rice paddy production that is common in some subregions within the continent. However, most of these studies do not provide explicit details of how rice production was simulated in SWAT. Other research has revealed that significant problems occur when trying to represent rice paddy systems in standard versions of SWAT, due to limitations in algorithms based on the runoff curve number approach or the pothole option. In response, key modifications have been made to SWAT in recent studies that have resulted in a more accurate representation of rice paddy systems. These developments point to the need for the incorporation of an enhanced rice paddy module within SWAT to better capture rice paddy hydrological and pollutant dynamics, which would support improved use of the model in Asia and other rice production regions. Subtopics related to simulating rice production in SWAT are discussed as follows: 1) an overview of global rice production; 2) history of SWAT development; 3) typical approaches for simulating rice production; 4) problems associated with the typical approaches; 5) recent code modifications to address deficiencies in replicating rice paddy systems; 6) recommendations for developing a standard rice paddy module for future SWAT codes.

    DOI: 10.25165/j.ijabe.20221501.7147

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  • Evaluation of drought features in the dakbla watershed, central highlands of Vietnam Reviewed International journal

    Vo Ngoc Quynh Tram, Hiroaki Somura, Toshitsugu Moroizumi

    Hydrological Research Letters   15 ( 3 )   77 - 83   2021.9

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    The drought impacts in the Dakbla watershed were assessed based on a combination of hydrological modeling and drought indices. Three drought indices, the Standardized Precipitation Index (SPI), Standardized Soil Moisture Index (SSI), and Streamflow Drought Index (SDI) were utilized to evaluate the drought features of meteo-hydrology and agriculture. The results indicated that these indices are well adapted to the local conditions, especially the 12-month time scale. Evaluations of drought features on the watershed scale could provide more specific information regarding drought risk than regional-scale/district-level assessments, because a watershed is a hydrologically fundamental unit to consider water resources management. Additionally, evaluations of drought impacts using the SSI showed longer and higher trends than those using the SPI and SDI in terms of drought duration and frequency. Considering the spatial distribution of drought frequency, the areas predominated by agricultural land in the target watershed had higher drought risk. Thus, assessment of agricultural droughts along with meteo-hydrological droughts is extremely important to support realistic local drought management strategies by considering water availability, water balance, and soil characteristics, especially in specific agricultural areas.

    DOI: 10.3178/hrl.15.77

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  • Environmental flow sustainability in the Lower Limpopo River Basin, Mozambique Reviewed International coauthorship International journal

    Osvaldo Silva Zefanias Nhassengo, Hiroaki Somura, June Wolfe

    Journal of Hydrology: Regional Studies   36   100843   2021.8

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    Study region: This study focuses on the Lower Limpopo River basin (LLRB) in Mozambique, Africa. Study focus: Maintaining environmental flows necessary for ecosystem sustainability represents a significant challenge to water resource management. In this study the sustainability of LLRB was evaluated by comparing hydrologic availability with ecological and anthropogenic needs. Current river ecological status was scored with a habitat integrity index verified through ground-truthing field surveys and aerial imagery data. Local stakeholder interviews were used to further evaluate the habitat index scores. Deficiencies between water availability and ecological-human requirements were assessed with a water scarcity index. New Hydrological Insights for the Region: Four environmental flow categories defined as “Excellent”, “Fair”, “Poor”, and “Degraded” coincided to approximately 50 %, 39 %, 27 %, and 14 % of the natural mean annual flow, respectively. Stakeholder interview responses indicated annual water shortages currently occur between August and November and coincide with “Poor” and “Degraded” environmental flow conditions. Water supplies appear to meet consumption needs when calculated on an annual basis with the water scarcity index. However, when calculated monthly, there is not enough to meet human water demand between August and October. This deficit period will likely expand from June to November due to projected increases in future water demands. As the greatest water use in the basin is agricultural irrigation, long-term environmental flows sustainability will likely depend upon effective irrigation management.

    DOI: 10.1016/j.ejrh.2021.100843

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  • The impacts of land-use input conditions on flow and sediment discharge in the dakbla watershed, central highlands of Vietnam Reviewed International journal

    Vo Ngoc Quynh Tram, Hiroaki Somura, Toshitsugu Moroizumi

    Water (Switzerland)   13 ( 5 )   2021.3

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    The main objective of this study was to evaluate various land-use input conditions in terms of the performance improvement found in consequent flow and sediment simulations. The soil and water assessment tool (SWAT) was applied to the Dakbla watershed from 2000 to 2018. After the calibration and validation processes, dissimilar effects between the input conditions on the flow and sediment simulations were confirmed. It was recognized that the impact of the land use on the sediment simulation was more sensitive than with the flow simulation. Additionally, through monthly evaluation, the effects against the flow and sediment in the rainy season were larger than those in the dry season, especially for sediment simulation in the last three months from October to December. Changing land-use conditions could improve flow and sediment simulation performance better than the performance found with static land-use conditions. Updated land-use inputs should be considered in simulations if the given land-use condition changes in a relatively short period because of frequent land-use policy changes by a local government.

    DOI: 10.3390/w13050627

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  • Organic matter clogging results in undeveloped hardpan and soil mineral leakage in the rice terraces in the Philippine cordilleras Reviewed International coauthorship International journal

    Tomoyo Kurozumi, Yasushi Mori, Hiroaki Somura, Milagros O-How

    Water (Switzerland)   12 ( 11 )   1 - 13   2020.11

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    © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Rice terraces in Cordillera, Philippines, a world cultural heritage site, are threatened by the risk of collapse. It is crucial to manage these rice terraces for their conservation, while simultaneously practicing traditional farming. We examined the soil environment and investigated its effects on rice terrace conservation, by focusing on the hardpan condition; infiltration process, which is related to the collapse of rice terraces; and soil nutrition conditions in these sites. Field survey and soil analysis revealed that in areas where the hardpan was not sufficiently developed and water infiltration was effectively suppressed, organic matter content was significantly high, suggesting organic matter clogging. In these rice terraces, the amounts of P, K, Ca, and Mn were significantly low, showing the mineral leaching under reductive soil conditions. Therefore, hardpan formation, rather than organic matter clogging, is essential for the suppression of infiltration and prevention of potential terrace collapse. Because hardpan formation or organic matter clogging cannot be identified from the surface of flooded rice paddies, it is difficult to identify the influencing factor. Thus, we suggest that the hard soil layer should be checked before the planting season and drainage is allowed after the cropping season in the rainy season.

    DOI: 10.3390/w12113158

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  • Developing a hydro-chemical model of Ise Bay watersheds and the evaluation of climate change impacts on discharge and nitrate-nitrogen loads Reviewed International journal

    Takeo Onishi, Jun Yoshino, Ken Hiramatsu, Hiroaki Somura

    Limnology   21 ( 3 )   465 - 486   2020.8

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    © 2020, The Japanese Society of Limnology. The objective of this study was to develop a hydro-chemical model using the Soil and Water Assessment Tool (SWAT) and to evaluate the climate change impacts on discharge and nitrate-nitrogen loads from Ise Bay watersheds (the Kiso, Nagara, Ibi, and Shonai rivers). Using a regional climate model, through the dynamic downscaling approach, present and future climate data were generated at a 2 km spatial resolution. The pseudo-global warming downscaling approach under the A1B scenario was adopted for future climate prediction. Then, the optimized SWAT model, driven by the present and future climate data, was executed. The following results were obtained: (1) the significant increase of precipitation in May and June and decrease in August in the future climate scenario, and consequent discharge from the target watersheds also increased in May and June and decreased in August and September; (2) Due to the change in discharge, nitrate-nitrogen loads of the Kiso, Nagara, and Ibi rivers also increased in May and June and decreased in August and September; and (3) While nitrate-nitrogen load from deciduous forest tends to decrease, the one from evergreen forest tends to increase. The response of the model indicated the possibility of an increase in nitrogen uptake by deciduous forests.

    DOI: 10.1007/s10201-020-00622-2

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  • Assessment of soil erosion in social forest-dominated watersheds in Lampung, Indonesia Reviewed International coauthorship International journal

    Rahmah Dewi Yustika, Hiroaki Somura, Slamet Budi Yuwono, Bustanul Arifin, Hanung Ismono, Tsugiyuki Masunaga

    Environmental Monitoring and Assessment   191 ( 12 )   2019.12

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    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media {LLC}  

    Social forestry policies grant local communities the right to access protected forest areas contingent upon certain governmental criteria. However, the adoption of social forestry is known to alter land-cover patterns and promote soil erosion. This study assessed the water quality of Sekampung Hulu and Sangharus Rivers in Lampung, Indonesia, based on their total suspended solid (TSS) concentrations. Subsequently, the extent of soil erosion in the two watersheds was determined, and best management practices (BMPs) were recommended for the study area. Water sampling was conducted in 2016 to estimate TSS levels in the two watersheds. Additionally, the Universal Soil Loss Equation (USLE) was integrated with an ArcGIS model to evaluate soil erosion in the watersheds. The results indicated that TSS concentrations in the Sekampung Hulu and Sangharus Rivers ranged from 36-813 mg L--(1) and 16-146 mg L-1, respectively. Further, the average soil erosion rates in the Sekampung Hulu and Sangharus watersheds were 12.5 Mg ha(-1) year(-1) and 5.6 Mg ha(-1) year(-1), respectively. The results indicated that young coffee trees increased soil erosion rates, especially in areas characterized by vulnerable soil. The USLE results concurred with the TSS analysis and indicated higher erosion rates for the Sekampung Hulu watershed than the Sangharus watershed. The application of BMPs, including conversion to agroforestry coffee, cover crops, and contour systems, was effective in reducing soil erosion in both the Sekampung Hulu and Sangharus watersheds.

    DOI: 10.1007/s10661-019-7890-5

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  • Impact of Human Activities and Natural Processes on the Seasonal Variability of River Water Quality in Two Watersheds in Lampung, Indonesia Reviewed International coauthorship International journal

    Rahmah Dewi Yustika, Hiroaki Somura, Slamet Budi Yuwono, Tsugiyuki Masunaga

    Water   11 ( 11 )   2363 - 2363   2019.11

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    This study identified seasonal water quality characteristics in two adjacent mountainous rivers (Sangharus and Sekampung Hulu Rivers) in Lampung, Indonesia and determined the impacts of fertilizer application on river chemistry as a result of social forestry management. In 2016, we measured water chemistry and conducted a farmers' questionnaire survey to obtain information on fertilizer application. The water quality results indicated that several parameters, including nitrate (NO3) and phosphate (PO4), were significantly higher in the Sangharus River than in the Sekampung Hulu River. In addition, several parameters were influenced by dilution from high river flow in the rainy season. Some parameters were likely influenced by the weathering of parent materials. By contrast, electrical conductivity (EC) and NO3 were higher in the rainy season, which was likely linked to the dominant timing of urea fertilizer application during this season. Despite the application of fertilizers in the watersheds, NO3 levels remained below the recommended standard. However, aluminum and iron concentrations were higher than the recommended level for drinking water, which was likely due to elevated soil erosion from improper land management. Therefore, we recommend that effective land management policies be implemented through the adoption of soil conservation practices for nutrient loss prevention.

    DOI: 10.3390/w11112363

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  • Evaluation of the effects of climate change on field-water demands using limited ground information: a case study in Balkh province, Afghanistan Reviewed International coauthorship International journal

    Abdullah Jami, Masahiro Tasumi, Thomas Michael Mosier, Hiroaki Somura, Toru Konishi

    Irrigation Science   37 ( 5 )   583 - 595   2019.9

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    © 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Climate change is a significant global issue that will affect regional agriculture and water management of irrigation supplies. In this study, we project climate change impacts on water and irrigation requirements for major crops—wheat, cotton, and apricots—in Balkh province, Afghanistan. The methodology utilizes satellite imagery to overcome limitations in ground measurements necessary to understand current crop conditions and cultivation schedules for the study site. The climate model-averaged results project an increasing trend in both crop water and irrigation requirements for the study area, with larger trends for the climate model and scenario combinations that project the largest temperature increases. Future trends in the year-to-year variability of field water requirements do not contain a clear trend for most crops. The magnitude of projected changes vary significantly between individual climate models, demonstrating the importance of applying multiple climate models to project future conditions in agricultural water management. The results demonstrate the efficacy of using globally available data, including satellite imagery and global climate model information, to overcome lack of in situ observations. The findings also highlight challenges to current agricultural paradigms in areas such as Afghanistan that are arid to semi-arid and do not have adequate irrigation infrastructure.

    DOI: 10.1007/s00271-019-00638-2

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  • Impacts of hydrological changes on nutrient transport from diffuse sources in a rural river basin, western Japan Reviewed International journal

    J. Ide, I. Takeda, H. Somura, Y. Mori, Y. Sakuno, Y. Yone, E. Takahashi

    Journal of Geophysical Research - Biogeosciences   124 ( 8 )   2565 - 2581   2019.8

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Geophysical Union (AGU)  

    DOI: 10.1029/2018JG004513

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2018JG004513

  • Relationship between water quality variations and land use in the Batutegi Dam Watershed, Sekampung, Indonesia Reviewed International coauthorship International journal

    Hiroaki Somura, Slamet B. Yuwono, Hanung Ismono, Bustanul Arifin, Fitriani Fitriani, Ryohei Kada

    Lakes & Reservoirs: Science, Policy and Management for Sustainable Use   1 - 9   2019.3

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1111/lre.12221

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  • Importance of considering nutrient loadings from small watersheds to a lake – A case study of the Lake Shinji watershed, Shimane Prefecture, Japan Reviewed International journal

    Hiroaki Somura

    International Journal of Agricultural and Biological Engineering   11 ( 5 )   124 - 130   2018.9

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    Contributors:
    Hiroaki Somura (Corresponding author)
    Hidenobu Kunii
    Yasumichi Yone
    Ikuo Takeda
    Hirokazu Sato

    DOI: 10.25165/j.ijabe.20181105.4351

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  • Behavior of dissolved organic matter in the two rivers inflowing to Lakes Shinji and Nakaumi Reviewed

    Sugitani Y, Somura H, Takeda I

    Laguna   23   47 - 58   2017.3

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    Authorship:Corresponding author   Language:Japanese   Publishing type:Research paper (scientific journal)  

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    Other Link: http://orcid.org/0000-0002-2592-7174

  • Behavior and Mass Balance of Iron and Phosphorus in a Paddy Field Area with Sediment Accumulation of Iron Oxides Reviewed

    TAKEDA Ikuo, TAKATA Ryunosuke, SOMURA Hiroaki, SATO Hirokazu

    Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering   301 ( 1 )   57 - 63   2016

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Japanese Society of Irrigation, Drainage and Rural Engineering  

    Iron is known to be significantly related with phosphorus runoff from watersheds, yet there is a lack of knowledge regarding this phenomenon from the viewpoint of the iron load. Therefore, we conducted a 17-month investigation on the behavior and annual mass balance of iron and phosphorus in a paddy field area where sediment of iron oxides accumulated. Most iron and phosphorus were present as particulate matter, with low concentrations of dissolved ions. Annual net-outflow loads of iron and phosphorus were 108.6 kg/ha (irrigation period: 37.3 kg/ha; non-irrigation period: 71.3 kg/ha) and 3.40 kg/ha (irrigation period: 1.49 kg/ha; non-irrigation period: 1.91 kg/ha), respectively. A possible reason that no phosphorus purification was observed at the study site despite the sufficient amount of iron, which has adsorption capacity for phosphorus, is sediment detachment and runoff due to water flow in the drainage canal. This suggests that management of phosphorus-rich sediment is an essential factor for controlling the outflow of phosphorus.

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  • Characteristics and potential usage of dissolved silica in rice cultivation in Sumani Watershed, Sumatra, Indonesia Reviewed

    Somura H, Darmawan, Sato K, Ueno M, Husnain, Aflizar, Masunaga T

    Pertanika Journal of Tropical Agricultural Science   39 ( 4 )   601 - 615   2016

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    Research on watershed silica dynamics in Indonesia has been sparse as most of the focus on water environment has centred on suspended sediments, nitrogen and phosphorous. Thus, Si concentrations in rivers and their seasonal and spatial variations are not well understood. Silicon helps rice plants to overcome abiotic and biotic stresses by preventing lodging and increasing resistance against pests and diseases. Rice is one of the more important crops in the country, and information on Si concentrations in rivers is useful because river water is a primary irrigation source. In this study, we conducted a preliminary research on temporal and spatial variations in dissolved Si (DSi) concentrations at watershed scale to help achieve an efficient use of Si resources through irrigation water management. The Sumani Watershed, located approximately 50 km east of Padang City in West Sumatra, Indonesia, was selected as the target area. Lake Dibawah lies on the upstream end of the watershed, and water is discharged from the watershed into Lake Singkarak. The results verified that Lake Dibawah had a dam effect of naturally reducing DSi concentrations in water. In addition, the average DSi concentration from the samples obtained from rivers, small channels, and ditches from October 2013 to December 2014 did not show strong seasonal patterns at each site but revealed clear spatial differences among sub-watersheds linked to the groundwater from Mt. Talang. The watershed has a high capability of supplying DSi to paddy fields via irrigation water.

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  • The Relationship between Examination Scores and the Timing of Lecture Video Viewing in a Flipped Classroom Plan Reviewed

    Somura H, Kazumi D, Omata K

    Japan Journal of Educational Technology   40 ( Suppl. )   9 - 12   2016

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  • Spatial variations in river nitrate concentration from upper toward lower reaches in the hilly and mountainous area

    Ide Jun'ichiro, Somura Hiroaki, Nakamura Takashi, Mori Yasushi, Takeda Ikuo, Nishida Kei

    The Japanese Forest Society Congress   127   624 - 624   2016

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  • Hydrological Effects on Relationships Between N-15 of River Nitrate and Land Use in a Rural River Basin, Western Japan Reviewed

    J. Ide, H. Somura, T. Nakamura, Y. Mori, I. Takeda, K. Nishida

    RIVER RESEARCH AND APPLICATIONS   31 ( 5 )   639 - 649   2015.6

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    This study aimed to examine how the relationship between N-15 of nitrate (N-15(NO3)) in rivers and land use within a river basin changes with varying hydrological conditions. This information would aid in identifying the dominant source contributing to increased nitrate concentrations in rural rivers. For this, N-15(NO3) in river water was investigated monthly in the five subbasins of the Hii River basin (area: 911km(2)), western Japan, for 1year and 3months. There were significant correlations (p&lt;0.05) between N-15(NO3) and the land-use ratio (i.e. ratios of forested, agricultural and residential areas in a subbasin) for the majority of the observation days, indicating that N-15(NO3) reflected land use within the basin. N-15(NO3) ranged from +1.4 parts per thousand to +8.5 parts per thousand and was lower in a subbasin with a higher forested area ratio. We found that the absolute value of the regression slope of the relationship between N-15(NO3) and the land-use ratio decreased with increasing river discharge. This finding demonstrates that differences in N-15(NO3) among subbasins with different land-use compositions became smaller under higher flow conditions. Because N-15(NO3) decreased with increasing river discharge, the small absolute value of the regression slope under high flow conditions indicates that forested areas could be the dominant source of river nitrate during high flows in all subbasins investigated regardless of land-use composition. The results suggest that forested areas make a large contribution to the increase in nitrate concentration in downstream rivers during high flows, because the nitrate concentration increased with increasing river discharge. Copyright (c) 2014 John Wiley & Sons, Ltd.

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  • Estimation of nutrient input by a migratory bird, the Tundra Swan (Cygnus columbianus), to winter-flooded paddy fields Reviewed

    Hiroaki Somura, Tsugiyuki Masunaga, Yasushi Mori, Ikuo Takeda, Jun'ichiro Ide, Hirokazu Sato

    AGRICULTURE ECOSYSTEMS & ENVIRONMENT   199   1 - 9   2015.1

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    Thousands of Tundra Swans visit winter-flooded paddy fields in the study area, Yasugi city, Shimane Prefecture, Japan every year for overwintering from November to March. Since 2004, they have roosted in the paddy fields during the night and foraged in the paddy and surrounding fields during the day, coinciding with the time when farmers began using winter-flooded paddy fields. Before 2004, the swans visited the area for foraging during the day and roosted at nearby lakes, wetlands, and sandbars along rivers during the night. When the swans visited our target paddy fields, the water gradually became green and began to emit an ammonia-like odor. In this study, we investigated the changes in the water qualities of winter-flooded paddy fields and the influence of bird excrement on water quality in the paddy fields during winter, and then estimated the amounts of nitrogen (N) and phosphorus (P) provided by bird droppings to the paddy fields. The mean concentrations of N, P, suspended sediment, and total organic carbon were higher in the overwintering season than during the irrigation season. This trend was observed in both the first and second seasons of the study. The spatial distribution of electric conductivity (EC) measured using a GEM-2 broad-band electromagnetic sensor coincided with that of the matted sites of Tundra Swans in the paddy field, which indicated that the excrement of the swans affected the EC distribution. The total input amounts of N and P from the birds' excrement to the flooded paddy fields were estimated using a simple model that considered bird counts and probable nutrient content of feces, and the amounts were found to be equivalent to approximately 30% of those present in the standard fertilizers used for rice during the irrigation period. These results suggested that the excrement from the swans markedly influences the water qualities of winter-flooded paddy fields. (C) 2014 Elsevier B.V. All rights reserved.

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  • Secular Changes of Statistical Dry-Season Discharges in Hii River Basin Reviewed

    Journal of rainwater catchment systems   19 ( 2 )   51 - 55   2014.1

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  • Improving water quality in the Nile Delta irrigation network by regulating reuse of agricultural drainage water Reviewed

    Khater, A, Kitamura, Y, Shimizu, K, Somura, H, Abou El, Hassan, W.H

    Food, Agriculture and Environment   12 ( 3-4 )   329 - 337   2014

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  • A Probability of Charcoal as Woody Carrier in Phosphorus Recovery from Natural Water Bodies Using Biogenic Ion-Oxides Reviewed

    Journal of the Agricultural Engineering Society, Japan   289 ( 1 )   55 - 56   2014

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  • Evaluation of management practices in forest soil environments using a multi-frequency electromagnetic sounding system Reviewed

    124 ( 124 )   17 - 24   2013.7

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  • Difficulty and Improvement for Application of SWAT Model to Rice Paddy Watershed Reviewed

    81 ( 12 )   983 - 987   2013

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  • Impact of suspended sediment and nutrient loading from land uses against water quality in the Hii River basin, Japan Reviewed International coauthorship International journal

    H. Somura, I. Takeda, J. G. Arnold, Y. Mori, J. Jeong, N. Kannan, D. Hoffman

    JOURNAL OF HYDROLOGY   450   25 - 35   2012.7

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    Lake Shinji lies in eastern Shimane Prefecture, and is typical of brackish lakes in Japan. Water quality of the lake does not meet the expected environmental standards for total nitrogen (TN) and total phosphorus (TP), even though the national and prefectural governments have tried to improve water quality by developing maintenance scenarios for sewage, plant effluent, agricultural activity, and forestry. Consequently, detailed data of nutrient loading to the lake from river inflows is crucial to support strategies for improving the lake water environment. The Hii River contributes approximately 80% of the discharge flowing into the lake. In this study, we examine the Hii River catchment with a focus on land uses such as paddy fields, upland fields, residential areas, and forestry. Average annual discharges of suspended sediment (SS), TN, and TP loads were determined at Otsu, near the outlet of the basin into Lake Shinji. We also determined average yield per unit area of SS, TN, and TP loads from each land use. Yields per unit area from upland areas were the greatest, whereas yields from forests were the lowest. Forests were the largest contributor of SS, TN, and TP in the basin, because of its dominant land area. Upland fields had the second largest impact on these loads in the basin, because fertilizer applied to the fields is a major source of nitrogen (N) and phosphorus (P). large differences in yields per unit area between fine and rainy day conditions were also observed, especially for SS and TP loads. Furthermore, we determined that a major pathway of N to the river was through groundwater, regardless of land use, whereas P was transported to the river with sediments, especially in paddy and upland fields. Based on these analyses, it will be difficult to reduce the SS load discharge in the basin in the future, because forestry is the major source. In contrast, N and P load reductions are straightforward, because the primary source is agricultural, and appropriate management of fertilizer application will be a key factor in reducing loads. (c) 2012 Elsevier B.V. All rights reserved.

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  • 島根県隠岐の島町スギ人工林における間伐の現状 Reviewed

    高橋絵里奈, 米康充, 森也寸志, 宗村広昭, 井手淳一郎, 佐藤利夫, 竹内典之

    森林応用研究   21 ( 2 )   9 - 16   2012

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  • 斐伊川流域における確率水文量の経年変化 Reviewed

    佐藤裕和, 武田育郎, 宗村広昭

    土木学会論文集B1(水工学)   68 ( 4 )   1387 - 1392   2012

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  • Simulation of nutrients from an agricultural watershed in Japan using the SWAT model Reviewed

    T. Kato, H. Somura, H. Kuroda, H. Nakasone

    International Agricultural Engineering Journal   20 ( 3 )   40 - 49   2011

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    The Soil and Water Assessment Tool (SWAT) model was applied to the Yamada River watershed to investigate the potential for using the model for watersheds characterized by circular irrigated paddy and livestock production systems in Japan. The Yamada River watershed, a typical mosaic land use in an agricultural watershed in the Ibaraki Prefecture, includes small valleys; where the paddy fields with a circular irrigation system are located along the river on lowlands and a forest, vegetable fields, and livestock barns are located in the surrounding uplands. The runoff characteristics were significantly different between the irrigation and non-irrigation periods in the study site, and the observed runoff was well simulated using the SWAT model by setting different parameters for the irrigation and non-irrigation periods. The Nash-Sutcliffe coefficient (E Ns), coefficient of determination (r 2), and relative error (RE) statistics were 0.86, 0.87, and 2.0 for the irrigation period and were 0.67, 0.68, and 2.6 for the non-irrigation period. However, the observed nutrient concentrations were not simulated well. The E NS and r 2 values were very weak and the RE values were not satisfactory. Improved estimates of storage nutrients in the vegetable fields and livestock wastes should be considered for further SWAT simulation, as well as improved algorithms for simulating rice paddy systems.

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  • Characterizing Soil Infiltration Water Quality in Forest Watershed during Heavy Rainfall Reviewed

    Morisawa Taihei, Mori Yasushi, Ide Jun'ichiro, Somura Hiroaki, Takeda Ikuo, Inoue Mitsuhiro

    Journal of Rainwater Catchment Systems   16 ( 2 )   61 - 67   2011

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    Soil infiltration process greatly contributes to the hydrological process in watershed, thus, soil infiltration water and runoff water were collected to characterize pollutant load from two planted forests. Especially, this study focused on the heavy rain which is reported to be increasing because of climate change. Glass fiber wick samplers were used to collect soil infiltration water samples, while runoff water was collected at the weir. Results showed that the wick sampler successfully collected the soil infiltration water without accumulating excess water above the device. The amounts of pollutant loads in soil infiltration water (total organic carbon; TOC, total nitrogen; TN) were positively correlated with pollutant loads in runoff water, which directly showed the contribution of soil water to runoff water. During the research period, environmental pollution load density in soil infiltration water was negatively correlated with sampled soil water volume. This could be a dilution effect caused by rainfall infiltration. However, after the heavy rainfall, soil infiltration water quality showed higher concentration than other rainfall events. The trend was clear in the long lasting strong rainfall, especially for well conductive forest slope. Because of the high permeable properties, pollutant loads from the soil surface easily reached to the depth of glass fiber wick (50cm depth), without filtering process through the soil body.

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  • Recovery of phosphorus from natural water bodies using iron-oxidizing bacteria and woody biomass Reviewed

    Ikuo Takeda, Hiroaki Somura, Yasushi Mori

    ECOLOGICAL ENGINEERING   36 ( 8 )   1064 - 1069   2010.8

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    There is a global concern that phosphorus (P) resources will be depleted in the near future, but the P flux from water to land is extremely limited, whereas the reverse flux is substantial. A new method for the recovery of P from natural water bodies was proposed using iron-oxidizing bacteria and woody biomass (heartwood of conifer) as a carrier and a practical demonstration was presented. The woody carrier was immersed in water abundant in iron-oxidizing bacteria and removed 1-10 weeks later. Our results showed that the immersed carrier collected biogenic iron (Fe) oxides produced by iron-oxidizing bacteria, and contained about 0.2 mg g(-1) of P after 3 weeks; this amount was higher than that contained in some P fertile soils used for cultivating plants. The biogenic Fe oxides on the carrier acted as a source of P for plant cultivation, and they could adsorb P from P-rich solutions (10 mg L(-1) of PO(4)-P). Although our study involved only a small-scale trial, the proposed method can potentially aid in the effective use of Pin water and in water quality improvement if conducted on a large scale. (C) 2010 Elsevier B.V. All rights reserved.

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  • A land use planning recommendation for the Sumani watershed, West Sumatra, Indonesia Reviewed

    Aflizar, Saidi, A, Husnain, Ismawardi, Bambang Istijono, Harmailis, Somura, H, Wakatsuki, T, Masunaga, T

    Tropics   19 ( 1 )   43 - 51   2010

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  • Characterizing infiltrated soil water quality as affected by rainfall condition Reviewed

    Journal of the Japanese Society of Soil Physics   114 ( 114 )   3 - 10   2010

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  • Soil erosion characterization in an agricultural watershed in West Sumatra, Indonesia Reviewed

    Aflizar, Saidi, A, Husnain, Indra, R, Darmawan, Harmailis, Somura, H, Wakatsuki, T, Masunaga, T

    Tropics   19 ( 1 )   29 - 42   2010

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  • Influence of puddling procedures on the quality of rice paddy drainage water Reviewed International journal

    Hiroaki Somura, Ikuo Takeda, Yasushi Mori

    AGRICULTURAL WATER MANAGEMENT   96 ( 6 )   1052 - 1058   2009.6

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    Drainage water quality in rice paddies was strongly influenced by the puddling of soil in the paddy fields by tractors and in response to opening of drainage gates. The concentrations of contaminants in drainage water increased rapidly when the puddling process began and were maintained at high concentrations throughout the puddling period. Moreover, the high concentrations did not decrease immediately after the puddling procedures ceased. Additionally, the ratio of dissolved nitrogen and phosphorous to total nitrogen and total phosphorous increased daily during the last half of the puddling period, due to discharge of chemical fertilizers with the drainage water. Also, the loads of particulate nitrogen and phosphorus discharged during the puddling period were larger than the loads discharge during irrigation. The discharge from paddy fields during puddling also increased the total annual contaminant load. (C) 2009 Elsevier B.V. All rights reserved.

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  • Impact of climate change on the Hii River basin and salinity in Lake Shinji: a case study using the SWAT model and a regression curve Reviewed International coauthorship International journal

    H. Somura, J. Arnold, D. Hoffman, I. Takeda, Y. Mori, M. Di Luzio

    HYDROLOGICAL PROCESSES   23 ( 13 )   1887 - 1900   2009.6

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    The impacts of climate change oil water resources were analysed for the Hii River basin and downstream Lake Shinji. The variation between saline and fresh water within these systems means that they encompass diverse ecosystems. Changes in evapotranspiration (ET), snow water equivalent, discharge into the basin, and lake salinity were determined for different climate scenarios. The impact of climate change on a brackish water clam found in the lake was then examined using simulated monthly variations of lake salinity and information from prior Studies of the clam.
    ET increased and snow water equivalent decreased for all scenarios incorporating temperature rise, particularly during the winter season. Furthermore, ET and snow water equivalent were not as sensitive to variations in precipitation and thus temperature rise was considered to be a major factor for these variables. Nevertheless, monthly discharge Volume was more influenced by variation in precipitation than variations in temperature. Discharge increased during both the summer and winter season, since precipitation contributed to river discharge instead of being stored as snow pack during the winter season. The magnitudes of salinity dilutions and concentrations predicted under the climate change scenarios Would not be lethal for adult clams. However, the egg-laying season of the clam would coincide with periods of strong salinity dilution in the lake. Since juveniles are less tolerant to changes in salinity, future generations of the clam may be affected and reproduction of the clam may be reduced by increasing precipitation in the future. Copyright (C) 2009 John Wiley & Sons, Ltd.

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  • 間伐遅れの針葉樹人工林における水文流出の特徴とその長期変動 Reviewed

    武田育郎, 福島晟, 宗村広昭

    農業農村工学会論文集   263   41 - 48   2009

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  • 間伐遅れの針葉樹人工林における水文特性とタンクモデル定数との関係 Reviewed

    戸田政仁, 武田育郎, 宗村広昭, 井手淳一郎

    応用水文   21   1 - 9   2009

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  • Long-term trends in water quality in an under-populated watershed and influence of precipitation Reviewed

    Takeda, I, Fukushima, A, Somura, H

    Journal of Water and Environment Technology   7 ( 4 )   293 - 306   2009

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    An investigation of the water quality in an under-populated watershed was conducted over a 15-year period in which data was collected at weekly intervals. The purposes of this study were to analyze the long-term trends in water quality and to evaluate the relationship between the water quality and precipitation. Concentrations of total phosphorus (T-P), chemical oxygen demand (COD), and suspended solids (SS) reached remarkably high values under heavy precipitation conditions, and these concentrations increased exponentially with the amount of precipitation. Over the course of this study, the population, number of factories, animals (cow and pig), and area of agricultural land exhibited clearly decreasing trends, while steady progress in domestic wastewater treatment was realized. However, no clear decrease in the parameters of water quality was observed, and some nitrogen, phosphorus, and COD concentrations increased even though no significant change in precipitation occurred. A possible hypothesis explaining this lack of a clear decrease in water quality is that specific pollutant outflows from forests and agricultural lands may have increased in recent years. This is because poorly managed forests and agricultural lands in the under-populated watershed have adversely affected the water quality of the rivers.

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  • Sensitivity analyses of hydrologic and suspended sediment discharge in the abashiri river basin, hokkaido region, Japan Reviewed International journal

    Somura, H., Takeda, I., Mori, Y.

    International Agricultural Engineering Journal   18 ( 1-2 )   27 - 39   2009

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  • Runoff Characteristics of Nitrate Nitrogen in a Yatsu Agricultural Catchment During Rainfall Events Reviewed

    KATO Tasuku, SOMURA Hiroaki, OSAWA Kazutoshi, KURODA Hisao

    Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering   261 ( 3 )   49 - 55   2009

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    Runoff characteristics of nitrate nitrogen (NO3-N) concentrations of drainage water were investigated in Yatsu agricultural catchment during rainfall events. With regard to the changes in the NO3-N concentrations for each rainfall event, the NO3-N concentrations showed a decreased tendency according to the increases in runoff by rainfall. When the runoff and the NO3-N concentrations for rainfall events during the irrigation or non-irrigation periods were plotted in a scattered diagram, they were significantly related to each other using a power function. The NO3-N concentrations during the irrigation period were below those at the similar runoff during the non-irrigation period, suggesting that irrigation water and a nitrogen removal function of paddy fields affected the No3-N concentrations during rainfall events. In special, the direct runoff was strongly related to the No3-N concentrations. In addition, the NO3-N concentrations decreased when the antecedent rainfall during the 5 days preceding the rainfall event (pre-5-day rainfall) was great, indicating that the pre-5-day rainfall affected the changes in the NO3-N concentrations. The results suggested that irrigation water, direct runoff, and antecedent rainfall affected the NO3-N concentrations of drainage water during rainfall events.

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  • Impacts of nutrient management and decrease in paddy field area on groundwater nitrate concentration: a case study at the Nasunogahara alluvial fan, Tochigi Prefecture, Japan Reviewed International coauthorship International journal

    Hiroaki Somura, Akira Goto, Hiroyuki Matsui, Elhassan Ali Musa

    HYDROLOGICAL PROCESSES   22 ( 24 )   4752 - 4766   2008.11

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    In order to help evaluate the trends in the NO(3)-N concentration in groundwater with a view to preventing further degradation in water quality in the future, a distributed groundwater quality model was constructed tor the Nasunogahara basin. The best fit for the groundwater table elevations by the flow component of the model was achieved with average mean absolute errors (MAEs) of 0.92 m for the calibration period and 0-83 in for the validation period. Moreover. the best fit for the NO(3)-N concentration by the water quality component was achieved with average mean relative errors (MREs) of 29-8% for the calibration period and 30.3% for the validation period. After developing a robust model. various change scenarios were tested specifically. the effects of effluent load control and a decrease in paddy field area on the NO(3)-N concentration in groundwater were predicted. The most intensively farmed area contributed about 40% of the total effluent load because of livestock fanning ill the basin. When the effluent load from this area was decreased by 50%, the average NO(3)-N concentrations at sites S1, S2 and S3 were reduced by about 15%: however, the average concentrations at S4 and S5 were reduced by only 1%. Furthermore. when the total effluent load from the concentrated livestock area was removed completely, the average groundwater NO(3)-N concentrations at SI, S2 and S3 were reduced by about 30% as compared with the original calculated results. In contrast. decreasing the area of the paddy fields in the basin did not greatly influence the groundwater NO(3)-N concentration. In the case of a 70% reduction in paddy field area, average NO(3)-N concentrations increased by about 7% at S1. S2 and S3. Copyright (C) 2008 John Wiley & Soils, Ltd.

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  • Decadal fluctuations in the consumption of irrigation water during the rainy season, Lower Mekong River Reviewed International journal

    Hiroaki Somura, Koshi Yoshida, Hajime Tanji

    HYDROLOGICAL PROCESSES   22 ( 9 )   1310 - 1320   2008.4

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    The importance of proper water management means that the consumption of irrigation water should be estimated even in areas where data are scarce. The Mekong River, particularly the lower part, is one area where irrigation water has received little research attention. Studies that seek to estimate the use of irrigation water in this area are restricted by a lack of hydrological data; consequently, alternative methods are required to obtain these data. One solution is the use of model simulations. The main difference between our approach and existing irrigation-water estimation models is that we consider agricultural data in estimating the use of irrigation water, especially that used for rice production, as these data are relatively easy to collect. As a result, rice production during the rainy season in the target area was computed for 10 years with errors of less than 30%. The average values of calculated and observed rice yields per hectare were 1.3 and 1.7 t/ha in Thailand, 2.5 and 2.7 t/ha in Lao PDR, and 1.2 and 1.3 t/ha in Cambodia, respectively. In addition, we clarified decadal fluctuations in horizontal supplied (HS) water and irrigation water. The average values of HS water supplied to the paddy fields during the simulation period were approximately 17.2 km(3)/rainy season in Thailand (388 mm), 0-81 km(3)/rainy season in Lao PDR (245 mm), and 4.4 km(3)/rainy season in Cambodia (322 mm). Comparisons with HS water (7.4 km3/rainy season) and the existing requirements for irrigation water revealed that the simulation yielded acceptable values, thus verifying the reproducibility of the model results. Finally, we calculated the average water balances during the growth period for rice. The highest amount of irrigation water per unit irrigated area during the rainy season was used in Lao PDR, though the volume of irrigation water was greatest in Thailand. Copyright (C) 2008 John Wiley & Sons, Ltd.

    DOI: 10.1002/hyp.6940

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  • Spatial Distribution of Water Quality and Load Units in the Iinashi River Basin, Shimane Prefecture, Japan Reviewed

    Somura, Hiroaki, Nakayama, Daisuke, Aizaki, Morihiro, Seike, Yasushi, Okumura, Minoru, Nishikata, Kumiko

    The Open Hydrology Journal   2   15 - 24   2008

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  • Soil environment monitoring by multi-frequency electromagnetic sounding Reviewed

    Journal of the Japanese Society of Soil Physics   109 ( 109 )   3 - 14   2008

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  • Development of Irrigation Water Allocation Model Considering Gate Operator Density, in Northeast Thailand Reviewed

    HIGUCHI Katsuhiro, TODA Osamu, YOSHIDA Koshi, SOMURA Hiroaki, TANJI Hajime

    JOURNAL OF JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES   20 ( 3 )   167 - 190   2007

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    Water management with appropriate gate operation is needed for irrigation areas where water shortages are serious. In this study, the irrigation water distributions of two irrigation projects in Northeast Thailand were analyzed and the efficiencies of water use were simulated from one day to 2 weeks. The efficiency of water distribution was calculated by using a hydraulic model under the operating schedule generated from human factors. Hydraulic structures such as a constant head orifice and spillway were included in the hydraulic model by using one-dimensional movement equations and continuity equations. The parameters of human factors were estimated from the measured data such as the gate operator density and water depth management. From the results, in the medium discharge, gate operation delays within two hours caused the error of water distribution within 5 %. However, if the gate operators operated the gates to the ideal opening height regularly every day, the error was within 5 % even in the actual density. In the high discharge, an overflow was caused regardless of gate operators density, the error of water distribution to the downstream was over 10 %

    DOI: 10.3178/jjshwr.20.167

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  • 管理状態の異なる森林からの集中豪雨に伴う汚濁負荷流出特性-土壌浸透水直接採取からの観察- Reviewed

    森澤太平, 森也寸志, 江草直和, 宗村広昭, 井上光弘

    応用水文   20   11 - 20   2007

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  • Hydro-meteorological observation and analysis of observed data at Tonle Sap Lake and its environs, urban and paddy areas Reviewed

    Takao Masumoto, Kumiko Tsujimoto, Hiroaki Somura

    Technical report of the National Institute for Rural Engineering   206 ( 206 )   219 - 236   2007

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  • Environmental Factors Affecting Fishes in a Paddy-field Area Reviewed

    Nishimura Keiichi, Takeda Ikuo, Fukushima Akira, Somura Hiroaki

    Journal of Rainwater Catchment Systems   12 ( 1 )   11 - 16   2006

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    Relationship between diversity indexes of fishes and environmental factors were evaluated. In this study, a field investigation was carried out in a paddy-field area in the eastern part of Shimane Prefecture. Parameters of this study were water qualities, fishes, and physical environmental factors (water depth, flow velocity, vegetation coverage, soil coverage of undersurface and habitat space) in drainage canals. Eleven species of fishes were observed in the investigation sites and diversity indexes were calculated by Shannon-Wiener method. Factor analysis was conducted with the diversity indexes of fishes and the environmental factors. As a result, higher values of diversity index were found with lower concentrations of chemical oxygen demand (COD), total organic carbon (TOC), nitrogen and turbidity. In addition, the higher indexes were also found with slower flow velocity and higher levels of vegetation coverage, soil coverage of undersurface, habitat space and water depth.

    DOI: 10.7132/jrcsa.KJ00004353082

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  • MODELING OF RADIATION SHADE FUCTION CONSIDERING SEASONAL CHANGE OF LEAF AREA INDEX OF RIPARIAN VEGETATION Reviewed

    YOSHIDA Koshi, SHIOZAWA Sho, TODA Osamu, SOMURA Hiroaki, TANJI Hajime

    Doboku Gakkai Ronbunshuu B   51   1225 - 1230   2006

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    Recently, multiple functions of river riparian vegetation are attracted in biological, environmental river engineering field. The decline of riparian vegetation strongly affects the river thermal environment, which also has a large impact on the ecological systems. In this study, a model that relates stream temperature with riparian vegetation was developed. The Nam Song River, which is a tributary of the Nam Ngum River flowing through the Vientiane Metropolis, was selected for field study. Meteorological data (air temperature, relative humidity, wind speed) were used, and the sink or source terms of the heat transfer equation were estimated from that data. NDVI (normalized difference of the vegetation index) remote sensing data was used for estimation of LAI (leaf area index) seasonal change. Simulations were made with several cases of riparian vegetation density, showing that river water temperature is more sensitive to river discharge change in the case of low density condition.

    DOI: 10.2208/prohe.51.1225

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  • 夏季の農業排水路における水生動物の多様性と環境因子との関係 Reviewed

    西村圭市, 武田育郎, 福島晟, 宗村広昭

    農業土木学会論文集   74 ( 2 )   99 - 105   2006

  • Estimation of supplementary water to paddy fields in the lower Mekong River basin during the dry season Reviewed International journal

    Hiroaki Somura, Hajime Tanji, Koshi Yoshida, Osamu Toda, Katsuhiro Higuchi

    PADDY AND WATER ENVIRONMENT   3 ( 3 )   177 - 186   2005.9

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    Efficient management of water resources in paddy fields requires an understanding of the volume of supplementary water used. However, quantifying the volume is laborious due to the large amount of data that must be collected and analyzed. The purpose of our study was to estimate the volume of supplementary water used in paddy fields, based on several years of available statistical data, and to provide information on how much water can be supplied to paddy fields in each target area. In this study, the lower Mekong River basin of northeast Thailand, Laos, and Cambodia was selected as the study area. In the first step, we used agricultural statistics for each country, rainfall data acquired from the Mekong River Commission Secretariat (MRCS), and the value of virtual water required per unit of rice production. Because several years of data were used for dry season harvested areas and rice production in each country, the supplementary water to paddy fields in each province was calculated using virtual water and rainfall. This method made it possible to estimate changes in supplementary water in each province. Through this study, the supplementary water to paddy fields during the dry season in three countries was approximated from the minimum number of data sets. Moreover, for cases in which it is not possible to procure agricultural water use data for a hydrological model simulation, an alternative solution is proposed.

    DOI: 10.1007/s10333-005-0015-5

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  • Estimation of Irrigation Water to Paddy Fields under Conditions of Poor Data Availability, Cambodia Reviewed

    Somura H, Tanji H, Yoshida K, Toda O, Masumoto T

    JOURNAL OF JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES   18 ( 1 )   22 - 34   2005

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    DOI: 10.3178/jjshwr.18.22

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  • Estimation of supplementary water capacity for non-irrigated paddy fields during the dry season in Northeast Thailand Reviewed

    Somura H, Yoshida K, Higuchi K, Toda O, Tanji H

    Journal of the Japanese Agricultural Systems Society   21 ( 3 )   167 - 176   2005

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    This study estimated the supplementary water capacity for paddy fields by estimating the water supply in each province during the dry season. Northeast Thailand was selected for this analysis because of the availability of agricultural statistical data distinguishing irrigated rice fields and non-irrigated rice fields during the dry season. This region is in Monsoon Asia, and so the climate has two seasons: the dry season and the wet season. Since about 70% of the annual rainfall is concentrated in the wet season, rice cannot be produced using only the dry season precipitation. In other words, farmers must obtain water from some other source to supply water to their paddy fields when growing rice in the dry season. Water is supplied from dam reservoirs in the irrigated rice fields, and water is supplied to the non-irrigated rice fields by gravity and small pumps from small ponds and canals. Thus, it was assumed that the amount of water supplied to paddy fields during the dry season can be calculated by subtracting rainwater during the dry season from the amount of water used in paddy fields. Based on rice production data, the values of water resources required to produce a unit weight of rice and rainwater, attempts were made to estimate the supplementary water capacities to paddy fields from the estimated supplied water and its maximum values in each province. Because there is no data for small ponds and canals for non-irrigated paddy fields in each province, the validity of the values estimated from the agricultural statistics was examined by comparing the supply water capacities for irrigated paddy fields estimated from the statistical data with those calculated from the Royal Irrigation Department data for large- and medium-scale reservoirs in each province. As a result, both differences tended to be less than 1 mm in the provinces whose harvested area of irrigated rice was small. It was therefore considered that supplementary water capacities to the non-irrigated paddy fields in each province can be estimated by the same method as for the irrigated paddy fields because it was assumed that the actual situation was similar to the non-irrigated paddy fields even if the classification of the rice fields was "irrigated". As a result, the supplementary water capacity tended to be high in the provinces through which the Chi River flows and the province upstream of the Mun River.

    DOI: 10.14962/jass.21.3_167

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  • Model Development for Estimating Supplementary Water to Paddy Fields during Rainy Seasons in the Lower Mekong River Basin Reviewed

    Somura H, Yoshida K, Higuchi K, Toda O, Tanji H

    PROCEEDINGS OF HYDRAULIC ENGINEERING   49   235 - 240   2005

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    Supplementary water should be estimated even in areas where data is scarce because of the importance of proper water management. The Mekong River, particularly the lower part (Lower Mekong River Basin), is one area where supplementary water has not been well researched despite the fact that this international river runs through four countries: Laos, Thailand, Cambodia and Vietnam. Studies to grasp the amount of supplementary water are restricted due to a lack of hydrological data, thus methods for obtaining these amounts are needed. One solution is model simulations. In this study, supplementary water was estimated by calculating back from rice production targeted at a macro scale. As a result, the supplementary water in Cambodia, Laos and Thailand was estimated from 1991 to 1995 through model calibration with rice production.

    DOI: 10.2208/prohe.49.235

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  • 河畔林保全による流域の河川水温管理 Reviewed

    吉田貢士, 宗村広昭, 樋口克宏, 丹治肇

    農業土木学会誌   73 ( 4 )   281 - 284   2005

  • Stream Temperature Analysis in Nam Ngum River Basin, Mekong Reviewed

    Yoshida, K, Tanji, H, Somura, H

    Annual Journal of hydraulic Engineering   48   1531-1535   2004

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  • 洪水リスクにおける脆弱性評価の検討 Reviewed

    丹治肇, 吉田貢士, 蘭嘉宣, 宗村広昭

    農業土木学会誌   72 ( 5 )   381 - 384   2004

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    DOI: 10.11408/jjsidre1965.72.5_381

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  • EFFECT OF DENSITY DIFFERENCES OF RIPARIAN VEGETATION ON THE RIVER THERMAL ENVIRONMENT Reviewed

    YOSHIDA Koshi, SOMURA Hiroaki, HIGUCHI Katsuhiro, TODA Osamu, TANJI Hajime

    Doboku Gakkai Ronbunshuu B   49 ( 1 )   1543 - 1548   2004

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    Publisher:Japan Society of Civil Engineers  

    The declines of river corridor vegetation density strongly affect to the river heat environment, and that change makes big impact to the ecological systems. In this study, stream temperature analysis model related with river corridor density was developed and applied to Nam Song River, Laos. Metrological data (air temperature, relative humidity, wind speed) were used, and sink or source terms of heat transfer equation were estimated from those data. Land cover GIS data was used for vegetation density analysis along the main river. As the result of simulation cases with several vegetation densities, river water temperature was more sensitive to river discharge change as decreasing of vegetation densities.

    DOI: 10.2208/prohe.49.1543

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  • 東南アジアの米の将来需要予測 Reviewed

    丹治肇, 多田稔, 宗村広昭, 吉田貢士

    農業土木学会誌   72 ( 9 )   795 - 797   2004

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    DOI: 10.11408/jjsidre1965.72.9_795

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  • カンボジアのコルマタージュ・システムの歴史と展望 Reviewed

    戸田修, 樋口克宏, 宗村広昭, 丹治肇

    農業土木学会誌   73 ( 1 )   31 - 34   2004

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  • 農業用水におけるライフ・サイクル・アセスメントの検討 Reviewed

    丹治肇, 吉田貢士, 蘭嘉宣, 宗村広昭

    農業土木学会誌   71 ( 12 )   1087 - 1090   2003

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    DOI: 10.11408/jjsidre1965.71.12_1087

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  • Modeling analysis of nitrate nitrogen pollution processes of groundwater in Nasunogahara basin Reviewed

    Somura H, Goto A, Mizutani M

    Transactions of the Japanese Society of Irrigation, Drainage and Reclamation Engineering   226   1 - 10   2003

  • Water quality forecast of Cidanau watershed, Indonesia, for watershed management planning, Reviewed

    Kato, T, Somura, H, Goto, A

    Rural and Environmental Engineering   43   3 - 12   2002

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  • Groundwater Nitrogen Pollution and Its Mechanism in Nasunogahara Basin, Tochigi Pref., Japan Reviewed

    Somura H, Masuda M, Goto A, Mizutani M

    Transactions of The Japanese Society of Irrigation, Drainage and Reclamation Engineering   219   71 - 79   2002

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Books

  • 水文・水資源ハンドブック

    The Japan Society of Hydrology Water Resources( Role: Contributor ,  14.1.1 人口増加と水問題)

    朝倉書店  2022.9  ( ISBN:9784254261745

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    Total pages:xii, 615p, 図版 [8] p   Language:Japanese

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MISC

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Presentations

  • 学生・職員・教員が共に考え活動する岡山大学 SDGs の取り組み Invited

    宗村広昭

    第58回 水環境フォーラム山口  2021.9.25  (公社)日本水環境学会中国・四国支部山口地域分科会

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    Event date: 2021.9.25

    Language:Japanese   Presentation type:Public lecture, seminar, tutorial, course, or other speech  

    Venue:オンライン   Country:Japan  

  • How should we manage a watershed for sustainable water environment? Invited International coauthorship International conference

    H. Somura, S. Yuwono , R. Yustika

    Japan Geoscience Union Meeting (JpGU) 2021  2021.6.4 

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    Event date: 2021.5.30 - 2021.6.6

    Language:English   Presentation type:Oral presentation (invited, special)  

  • 気象データを用いた機械学習による土壌水分量予測

    隅田 洸輝, 諸泉 利嗣, 宗村 広昭

    水文・水資源学会 日本水文科学会2023年度研究発表会  2023.9.5 

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    Event date: 2023.9.3 - 2023.9.6

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  • 降雨強度と農地土壌への天然ラテックス混和が流出流量に与える影響

    熊本 航己, 宗村 広昭, 諸泉 利嗣, 森 也寸志

    水文・水資源学会 日本水文科学会2023年度研究発表会  2023.9.4 

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    Event date: 2023.9.3 - 2023.9.6

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  • Evaluation of CMIP6 GCMs for Water Resources Modeling in The Tana River Basin, Kenya

    Daniel Mwendwa Wambua, Hiroaki Somura

    Japan Geoscience Union Meeting 2023  2023.5.23 

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    Event date: 2023.5.21 - 2023.5.27

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  • Exploring Synthetic Aperture Radar (SAR) data for a better understanding of irrigation status at paddy fields

    Aliya Binti Mhd Zahir, Hiroaki SOMURA

    Japan Geoscience Union Meeting 2023  2023.5.26 

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    Event date: 2023.5.21 - 2023.5.26

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  • Effects of natural latex to the surface flow and infiltration amounts under different rainfall intensity conditions

    Hiroaki Somura, Koki Kumamoto, Yasushi Mori, Jun Kano, Mamoru Matsushima, Bnaja Junhasavasdikul

    Japan Geoscience Union Meeting 2023  2023.5.26 

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    Event date: 2023.5.21 - 2023.5.26

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  • Natural rubber latex application to sandy loam in Thailand to improve the permeability and water holding capacity

    Yasushi Mori, Ryohei Otsuki, Hiroaki Somura, Jun Kano, mamoru matsushima, Bnaja Junhasavasdikul

    Japan Geoscience Union Meeting 2023  2023.5.26 

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    Event date: 2023.5.21 - 2023.5.26

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  • Evaluation of the Temporal behavior of Fulvic Acid Iron in Asahi River in Okayama Prefecture, Japan

    Rohdof Lactem Yengeh, Hiroaki Somura

    Japan Geoscience Union Meeting 2023  2023.5.26 

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    Event date: 2023.5.21 - 2023.5.26

    Language:English   Presentation type:Oral presentation (general)  

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  • Application of SWAT-MODFLOW Model in Srepok River Basin, Vietnam

    Sam Thao Truong, Hiroaki Somura

    Japan Geoscience Union Meeting 2023  2023.5.25 

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    Event date: 2023.5.21 - 2023.5.26

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  • The Journal of the Japan Society of Hydrology and Water Resources

    Hiroaki Somura, Junichiro Ide, Shinichiro Nakamura, Atsushi Higuchi

    Japan Geoscience Union Meeting 2023  2023.5.24 

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    Event date: 2023.5.21 - 2023.5.26

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  • Influence of climate variables on rice yield in different agrometeorological zones of Cote d’Ivoire.

    Yacouba Ouattara, Hiroaki Somura

    Japan Geoscience Union Meeting 2023  2023.5.22 

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    Event date: 2023.5.21 - 2023.5.26

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  • 岡山県の中山間地域が有する生態系サービスの価値再発見と見える化

    庄司怜, 宗村広昭, 諸泉利嗣

    2021年度(第70回)農業農村工学会大会講演会 

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    Event date: 2021.8.31 - 2021.9.2

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  • How should we manage a watershed for sustainable water environment? Invited

    Hiroaki Somura, Slamet Yuwono, Rahmah Yustika

    Japan Geoscience Union Meeting 2021  2021.6.4 

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    Event date: 2021.5.30 - 2021.6.6

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  • Discussion on cause and countermeasure of increasing trends in water quality of an under-populated watershed

    Takeda Ikuo, Somura Hiroaki, Mori Yasushi

    Proceeding of Annual Conference  2010  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    An investigation of the water quality in an under-populated watershed was conducted over a 15-year period in which data was collected at weekly intervals. In the study watershed, the pollutants derived from human activities decreased, but no clear decrease in the parameters of water quality was observed, and some nitrogen and phosphorus concentrations increased even though no significant change in precipitation occurred. A possible hypothesis explaining this lack of a clear decrease in water quality is that specific pollutant outflows from forests and agricultural lands may have increased in recent years. In addition, a new method for phosphorus recovery from natural water bodies was proposed using iron-oxidizing bacteria and woody biomass.

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  • EM sounding characterization of soil environment in artificial forest.

    MORI Yasushi, IDE Jun'ichiro, SOMURA Hiroaki, MORISAWA Taihei

    Proceeding of Annual Conference  2010  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Language:Japanese  

    A multi-frequency electro-magnetic (EM) sounding method was applied to the agriculture field to investigate the characteristics of non-point pollution load. Soil environmental properties such as differences in land management were analyzed with electrical conductivity (EC) maps. In addition, vertical EC profiles obtained from EM soundings were compared with EC in drainage ditch or river water. As results, surface soil EC maps successfully extracted the differences in land management affected by fertilizer application. Moreover, surface EC at the vertical profiles strongly related with drainage ditch or river EC.

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  • Enstimation of Environmental Load using Multi-frequency Electromagnetic Sounding

    Mori Yasushi, Somura Hiroaki, Egusa Naokazu, Ide Jun'ichiro, Morisawa Taihei

    Proceeding of Annual Conference  2009  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Event date: 2009

    Language:Japanese  

    A multi-frequency electro-magnetic (EM) sounding method was applied to the agriculture field to investigate the characteristics of non-point pollution load. Soil environmental properties such as differences in land management were analyzed with electrical conductivity (EC) maps. In addition, vertical EC profiles obtained from EM soundings were compared with EC in drainage river. As results, surface soil EC maps successfully extracted the differences in land management affected by fertilizer application. Moreover, surface EC at the vertical profiles strongly related with drainage river EC, showing most of the EC in the water was explained by surface EC maps at the EM sounding data. The proposed method has strength in obtaining EC data without sampling river water.

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  • Impact of Migratory Birds to Water Quality in paddy fields during Winter Season

    SOMURA HIROAKI, TAKEDA IKUO, MASUNAGA TSUGIYUKI

    Proceeding of Annual Conference  2009  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Language:Japanese  

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  • Characterizing infiltration soil water quality during regional heavy rainfall.

    Morisawa Taihei, Mori Yasushi, Ide Jun'ichiro, Somura Hiroaki, Takeda Ikuo, Inoue Mitsuhiro

    Proceeding of Annual Conference  2009  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Language:Japanese  

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  • Mitigation of stream temperature change with reservoir management

    Yoshida, K, Tanji, H, Somura, H, Higuchi, K, Toda, O

    Proc. of the 4th International Symposium on Environmental Hydraulics  2006 

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    Event date: 2006

    Language:English  

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  • Estimation of Rice production and Evapotranspiration by using Plant Growth Model in Khon Kaen, Northeast Thailand

    Yoshida, K, Shiozawa, S., H, Toda, O, Somura, H, Tanji, H

    Proc. of 2ndInternational Symposium on Sustainable Development in the Mekong River Basin  2006 

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    Event date: 2006

    Language:English  

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  • Effect of Riparian Vegetation Density and Discharge on Vulnerability of Stream Temperature

    YOSHIDA KOSHI, HIGUCHI KATSUHIRO, TANJI HAJIME, SOMURA HIROAKI, TODA OSAMU

    Proceeding of Annual Conference  2005  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Event date: 2005

    The declines of river corridor vegetation density strongly affect to the river heat environment, and that change makes big impact to the ecological systems. In this study, stream temperature analysis model related with river corridor density was developed and applied to Nam Song River, Laos. Meteorological data (air temperature, relative humidity, wind speed) were used, and sink or source terms of heat transfer equation were estimated from those data. Land cover GIS data was used for vegetation density analysis along the main river. As the result of simulation cases with several vegetation densities, river water temperature was more sensitive to river discharge change as decreasing of vegetation densities.

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  • Relation of corridor vegetation density and stream temperature

    Koshi Yoshida, Hiroaki Somura, Katsuhiro Higuchi, Osamu Toda, Hajime Tanji

    Dynamics and Biogeochemistry of River Corridors and Wetlands  2005  INT ASSOC HYDROLOGICAL SCIENCES

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    Event date: 2005

    Language:English  

    The decline of river corridor vegetation density strongly affects the river thermal environment, which also has a large impact on the ecological systems. In this study, a stream temperature analysis model related to river corridor vegetation density was developed and applied to the Nam Song River in Laos. Meteorological data (air temperature, relative humidity, wind speed) were used, and the sink or source terms of the heat transfer equation were estimated from those data. Land cover GIS data was used for vegetation density analysis along the main river. The results of simulation with several levels of vegetation density indicate that river water temperature is more sensitive to river discharge change in the case of low vegetation density.

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  • Estimation of Irrigation Water Volume by Using FAO CROPWAT Model Modified for Paddy at KM35 Irrigation Project Site, Laos

    Toda Osamu, Yoshida Koshi, Higuchi Katsuhiro, Somura Hiroaki, Tanji Hajime

    Proceeding of Annual Conference  2005  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Event date: 2005

    I analyzed one irrigation project site in the Mekong River Basin where was the most important for rice cultivation, because the irrigation would be absolutely necessary for stable food supply against rapidly fluctuating water resource or population growth of the Asia Monsoon. KM35 Irrigation Project Site in Savannakhet Province, Laos was selected as a study area and the irrigation water volume for last rainy season was estimated from actual yields by suing FAO CROPWAT Model. Thought this model was suitable for upland crops, some modifications to be suitable for paddy cultivation were needed. Estimated irrigation days were 34 on average. The estimated volume of irrigation water for the entire KM35 site was 7% of the active capacity of the reservoir. From the relation between partition height, hardpan depth and actual yield, it was said that high partition would make high yield.

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  • メコン川下流域の月流量特性と洪水氾濫流量の推定

    宗村 広昭, 丹治 肇, 桐 博英, 吉田 貢士

    水文・水資源学会研究発表会要旨集  2003  水文・水資源学会

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    Event date: 2003

    Language:Japanese  

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  • 農業用水におけるLCAの考察

    丹治 肇, 桐 博英, 宗村 広昭, 吉田 貢士

    水文・水資源学会研究発表会要旨集  2003  水文・水資源学会

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    Event date: 2003

    Language:Japanese  

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  • Evaluation of Stream Temperature and Soil Sediment Change with Dam Construction in Nam Ngum Basin, Mekong

    YSOHDIA KOSHI, TANJI HAJIME, KIRI HIROHIDE, SOMURA HIROAKI

    Proceeding of Annual Conference  2003  THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

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    Event date: 2003

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  • t日平均確率可能蒸発量の推定式

    諸泉 利嗣, 宗村 広昭

    水文・水資源学会/日本水文科学会2022年度研究発表会  2022.9.4 

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  • 高梁川流域におけるフルボ酸鉄濃度の評価

    宗村 広昭, 濱岡 幸太, Yengeh Rohdof, 諸泉 利嗣, 森 也寸志

    水文・水資源学会/日本水文科学会2022年度研究発表会  2022.9.4 

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  • Basic research on the mitigation of soil erosion in agricultural land using Thailand's natural latex

    宗村 広昭, 小野 慶人, 森 也寸志, 狩野 旬, 松島 守, Junhasavasdikul Bnaja

    JpGU2022  2022.6.1 

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  • Improving red-soil in Thailand by mixing natural latex

    森 也寸志, 本實 透, 宗村 広昭, 狩野 旬, 松島 守, Bnaja Junhasavasdikul

    JpGU2022  2022.6.1 

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  • Iron oxides and biochar incorporation into sediment to reduce phosphorus release

    Gamamada Liyanage Erandi Priyangika Perera, Morihiro Maeda, Hiroaki Somura, Yuta Nishina, Chiyu Nakano

    JpGU2022  2022.5.24 

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  • Hydrological impacts on nutrient transport from non-point sources in a semi-mountainous area, western Japan Invited

    Junichiro Ide, Ikuo Takeda, Hiroaki Somura, Yasushi Mori, Yuji Sakuno, Yasumichi Yone, Erina Takahashi

    JpGU2022  2022.5.23 

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  • Investigation of Point Level Data Between Remote Sensing Precipitation Data with Ground Precipitation Data to Support Water Resource Management Application in Humid Climate

    Aliya Binti Mhd Zahir, Hiroaki SOMURA

    JpGU2022  2022.5.23 

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  • Quantitative and Qualitative Evaluation of Etome Spring for Potable Water Bottling in Batoke, South West Region, Cameroon

    Rohdof Lactem Yengeh, Hiroaki SOMURA, Samuel Ayonghe Ndonwi, Wilson Fantong Yetoh

    JpGU2022  2022.5.23 

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  • Transition of Land and Water Use Status in Can Giuoc District, Long An Province, Vietnam

    2021.9.18 

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  • Evaluation of drought features in the Dakbla watershed, Central Highlands of Vietnam

    VO Ngoc, Quynh Tram, Hiroaki SOMURA, Toshitsugu MOROIZUMI

    2021.9.16 

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  • Improving reproducibility of flow and sediment simulation in the upstream of Sesan river basin

    VO Ngoc QuynhTram, Hiroaki SOMURA, Toshitsugu MOROIZUMI

    2021.8.19 

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  • Assessment of drought trends in the Dakbla watershed, Vietnam

    VO Ngoc QuynhTram, Hiroaki SOMURA, Toshitsugu MOROIZUMI

    Japan Geoscience Union Meeting 2021  2021.6.4 

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  • Factors affecting water quality in Sekampung and Sangharus sub-watersheds, Lampung, Indonesia

    Yustika R, Arifin B, Yuwono S, Ismono R, SomuraH

    平成30年度農業農村工学会大会講演会  2018 

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  • アフガニスタン北部2流域への水文モデルの適用

    宗村広昭, Ezatullah Rabanizada, Shoaib Saboory

    水文・水資源学会2018年度研究発表会  2018 

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  • Application of water balance model for evaluation of water resources and climate change impact in upper Panji-Amu River basin

    Rasekhudin S, Somura H

    平成30年度農業農村工学会大会講演会  2018 

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  • Causes of irrigation water scarcity in Landakhil irrigation canal, Nangarhar Province, Afghanistan

    Hashemi T, Somura H

    平成30年度農業農村工学会大会講演会  2018 

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  • コハクチョウ越冬による田面水や土壌への影響評価

    宗村広昭, 毛利達也

    平成30年度農業農村工学会大会講演会  2018 

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  • Effects of anthropogenic water demands against ecological integrity in lower Limpopo River

    Nhassengo, O, Somura, H

    平成29年度農業農村工学会大会  2017 

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  • アフガニスタン・ホルム流域への水文モデル適用可能性と課題

    宗村広昭, Rabanizada, E, Mohammad, S

    水文・水資源学会2017年度研究発表会  2017 

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  • Estimation of irrigation water Requirement in Zohrabi canal command area, Khulm watershed, Afghanistan

    Rabanizada, E, Somura, H

    平成28年度農業農村工学会大会  2016 

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  • アフガニスタン国ホルム流域ゾハラビ灌漑地区における灌漑要水量の推定

    農業農村工学会全国大会  2016 

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  • 島根県宍道湖・中海周辺のため池における30年間の水生植物相の変遷

    農業農村工学会全国大会  2016 

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  • Relationship between water quality variations and land use in the Batutegi Dam watershed, Sekampung, Indonesia

    The World Lake Conference 2016  2016 

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  • Potential availability of feces from a migratory bird, Tundra Swan, in winter-flooded paddy fields

    Myanmar-Japan International Symposium 2016  2016 

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  • コハクチョウの越冬が冬期湛水水田の土壌栄養塩量に与える影響に関する基礎研究

    農業農村工学会全国大会  2016 

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  • Determining potential sites of water harvesting structures using Multi-Criteria Analysis and GIS in Khulm Watershed, Afghanistan

    Mohammad, S, Somura, H, Shobair, S

    平成27年度農業農村工学会大会  2015 

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  • 斐伊川流域における窒素,リンの流出解析

    日本陸水学会 第76回大会  2011 

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  • Application of the SWAT model to the Abashiri River basin for impact assessment analysis to a brackish lake, Hokkaido region, Japan

    1st SWAT-SEA Conference  2009 

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  • Estimation of suspended solid discharge to a brackish lake in Shimane prefecture, Japan

    5th SWAT International Conference  2008 

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  • Relationship between farming activities and water quality variations of drainage water from paddy fields area

    World Environmental & Water Resources Congress 2008  2008 

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  • SWATモデルを用いたSS成分の流出量解析

    農業農村工学会大会  2008 

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  • Impact Assessment of Climate Change to Salinity in Brackish Lake: A Case Study with SWAT Model and Regression Curve

    AGU Fall Meeting  2007 

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  • Application of the SWAT Model to the Hii River Basin, Shimane Prefecture, Japan

    4th INTERNATIONAL SWAT CONFERENCE  2007 

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  • SWATモデルの斐伊川への適用

    農業農村工学会大会講演会  2007 

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  • 飯梨川における水質の空間分布

    汽水域国際シンポジウム2007  2007 

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  • 農業土木(分野)の現状

    サマーセミナー2006  2006 

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  • Irrigation Water Consumption during the Rainy Season in the lower Mekong River Basin

    The 2nd International Symposium on Sustainable Development in the Mekong River Basin  2006 

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  • 水田群が周辺環境に与える環境影響評価のための基礎的研究

    平成18年度農業土木学会大会  2006 

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  • Model Development for Supplementary Water Estimation in the Lower Mekong Basin

    19th Congress on Irrigation and Drainage  2005 

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  • Cost Allocation Model for Construction and Maintenance of Irrigation and Drainage Facilities

    19th Congress on Irrigation and Drainage  2005 

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  • Estimation of Recovery of Historical Fish Catch in Cambodia with consideration of Flood Water Levels

    19th Congress on Irrigation and Drainage  2005 

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  • 農業生産量データを用いた補給水量推定の試み

    平成17年度農業土木学会大会  2005 

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Research Projects

  • 微小・低重力環境下における高効率保水・有機質土壌の生成と展開

    Grant number:23K17386  2023.06 - 2027.03

    日本学術振興会  科学研究費助成事業  挑戦的研究(開拓)

    森 也寸志, 前田 守弘, 登尾 浩助, 齊藤 忠臣, 珠玖 隆行, 宗村 広昭

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    Grant amount:\25740000 ( Direct expense: \19800000 、 Indirect expense:\5940000 )

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  • Evaluation of carbon runoff from a coffee farming dominant protected forest watersheds and proposal of the forest conservation scenarios

    Grant number:22KK0093  2022.10 - 2026.03

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Fund for the Promotion of Joint International Research (Fostering Joint International Research (B))  Fund for the Promotion of Joint International Research (Fostering Joint International Research (B))

    宗村 広昭, 中野 知佑, 嶋 一徹

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    Grant amount:\20150000 ( Direct expense: \15500000 、 Indirect expense:\4650000 )

    社会林業政策による熱帯保護林内の開発・プランテーション化が,流域内の炭素流亡量に与える影響については研究例が少ない.この政策は“地元農民の生活基盤の安定化と環境保全との両立”を目標に東南アジアで拡大している.しかし実際は保護林内での不適切な営農が圃場斜面からの土壌流亡を加速させ,炭素の域内貯留能を低下させることで,水環境悪化やCO2放出を引き起こし,生態系に負の影響を与えていると考えられる.本研究は,現地観測によってその実態を解明すると共に,現地農民の斜面保全対策評価と未利用農業廃棄物の活用を通した保全対策の提案を行うことを目標にしている.これにより熱帯林流域の水環境保全と営農利用とを両立させる持続的な流域管理の実質化を進めたいと考えている.
    令和4年度はインドネシア・ランプン大学の研究者とのオンラインミーティングを通して研究計画のすり合わせを進めるとともに,主として,流域水環境を把握するため,流域内にある2つの河川(セカンプン川,サンハルス川)末端において河川水のサンプリングを開始した.なお,日本人研究者が頻繁に現地に赴くことは難しいため,定期的な河川水のサンプリングとそれらの保存はランプン大学の研究者に依頼し,共同で研究を実施している.

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  • Understanding the Mechanism of Soil Particle Aggregation Enhancement by Natural Latex and its Application to Soil Erosion Control Technology

    Grant number:22K19224  2022.06 - 2025.03

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Research (Exploratory)  Grant-in-Aid for Challenging Research (Exploratory)

    宗村 広昭, 狩野 旬, 森 也寸志

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    Grant amount:\6370000 ( Direct expense: \4900000 、 Indirect expense:\1470000 )

    圃場から水域への土壌流亡(炭素流亡)は世界的環境問題であり過去60年以上の研究蓄積にも拘わらず未解決である.本研究は天然ゴムラテックス(以下,天然ラテックス)の特性・利点(高い凝集能,カーボンニュートラルなど)を生かし問題解決に挑戦する.現状では天然ラテックスによる土壌流出特性や土壌環境変化とそれらの制御に関する研究は殆どない.研究チームは,水文学,土壌物理学,固体化学を専門とし,天然ラテックスによる土壌物理化学特性変化や土壌流亡抑制(炭素貯留)効果を評価する.
    令和4年度はタイ2圃場から採取された土壌(Sandy loam,Red clay)とタイ産の天然ラテックスを用いて実験を実施した.輸入した土壌量が限られるため小型の実験装置を構築した.構築した実験装置を用いて,降雨強度20㎜/hと50mm/hの条件下において,表面流出量と浸透量を計測し,天然ラテックス混和の有無および土壌種類の違いによる影響を評価した.その際,時間経過による影響も評価するため,24時間経過後に同一実験を繰り返した.
    その結果,降雨強度20mm/hの場合,天然ラテックスを土壌に混和することで,表面流出量が減少し,浸透量が増加する傾向が伺えた.特に,Sandy loamでその傾向が顕著に観測された.また24時間経過後に実施した実験においても同様の傾向であった.一方,降雨強度50mm/hの場合では,表面流出量の方が浸透量よりも顕著に大きく,天然ラテックス混和の有無による差異は小さいことが分かった.

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  • 植物根成孔隙マクロポアを活用した有機物蓄積と温室効果ガスの排出削減

    Grant number:21H04747  2021.04 - 2025.03

    日本学術振興会  科学研究費助成事業 基盤研究(A)  基盤研究(A)

    森 也寸志, 松本 真悟, 前田 守弘, 金子 信博, 宗村 広昭

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    Grant amount:\41860000 ( Direct expense: \32200000 、 Indirect expense:\9660000 )

    土壌カラムの管理の違いに,肥料,排水,マクロポア(粗大間隙)の有無の違いを設け,8管理3反復,24カラムで温室効果ガスの発生の違い設けると,肥料を投入しメタンが発生しやすい状況でも,排水が有り,マクロポアがあるときにメタンガスが有意に減少する成果を得た.同様に,牛ふん堆肥および3畜種混合堆肥を施用した土壌からのCO2, N2O発生を調べたところ,土壌NH4-N含量が高い場合には発生抑制が生じることがわかった.また,生ゴミ堆肥を施用した土壌からのCO2, N2O, CH4発生は堆肥化期間が長い方が少なくなることがわかった.
    一方,自然環境下で耕起と不耕起草生栽培1年目の農地で土壌の比較を行い,不耕起草生栽培では土壌表層の炭素隔離が進行し,可給態の栄養塩,特に有効態リン酸が耕起栽培の3倍程度の濃度に増加することが明らになった.イネは,カリウムとケイ酸が不足した条件下でも,他の作物に比べてカリウムとケイ酸を効率的に吸収した.そして,高活性なアルミニウムは根圏にとどまり,有機物と結合して,難分解性の土壌炭素を生成した.ケイ酸を強力に吸収する植物は,鉱物風化によって活性アルミニウムを増加させる役割を担っており,土壌中の炭素蓄積に寄与していると考えられた.
    土壌環境における水利用効率を最大にするため,流域(広域)レベルで水資源量の空間分布およびその季節変動を評価した.その中で土壌内への炭素貯留に大きな影響を持つ畑地,水田,プランテーションにおけるバイオマスの変動を中心に解析を進めた.また人為的な土地利用の変更が広域でのバイオマス量に与える影響について考察を進めた.

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  • 流域内の土地利用や土地管理が瀬戸内に流入する微量元素の挙動に与える影響

    2021

    公益財団法人 八雲環境科学振興財団  環境研究助成事業  特定研究

    Somura Hiroaki

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  • 灌漑用水配分のための人工知能に基づく対話型意思決定支援システムの開発と実地試験

    2018 - 2021

    JSPS  基盤研究B 

    加藤亮

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    Grant type:Competitive

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  • インドネシア・スカンプン川流域における生態系サービスの持続性と最適解に関する研究

    2017 - 2020

    JSPS  基盤研究B 

    嘉田良平

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    Grant type:Competitive

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  • フィリピン棚田群の劣化プロセスの解明と水文学的将来予測による最適環境管理

    2017 - 2020

    JSPS  基盤研究B 

    森 也寸志

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    Grant type:Competitive

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  • 渡鳥コハクチョウのもつ営農コスト削減ポテンシャルの検証と湖沼流域への負荷削減効果

    2015 - 2018

    JSPS  基盤研究C 

    宗村広昭

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    Authorship:Principal investigator  Grant type:Competitive

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  • 東南アジアにおける農林業と環境の両立にむけた生態系サービス支払いの制度設計

    2014 - 2017

    JSPS  基盤研究B 

    嘉田良平

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    Grant type:Competitive

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  • DPSIRモデルによる宍道湖における突発的な水草の分布拡大の評価と対策

    2013 - 2017

    JSPS  基盤研究B 

    國井秀伸

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    Grant type:Competitive

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  • 遺伝的アルゴリズムによる環境直接支払の最適化と農業政策への適用

    2013 - 2016

    JSPS  挑戦的萌芽研究 

    田中勝也

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    Grant type:Competitive

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  • 伊勢湾流域圏を対象とした水系総合モデルの開発と感度解析

    2013 - 2016

    JSPS  基盤研究C 

    大西健夫

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    Grant type:Competitive

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  • 熱帯地域における可給態ケイ酸動態調査と稲作のための自然供給システム構築

    2012 - 2015

    JSPS  基盤研究B 

    増永二之

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    Grant type:Competitive

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  • 汽水湖水環境の修復に向けた周辺河川流域の影響解析

    2012 - 2015

    JSPS  若手研究B 

    宗村広昭

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    Authorship:Principal investigator  Grant type:Competitive

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  • 統合的サステイナビリティ・インデックスによる環境政策評価モデルの構築

    2009 - 2011

    JSPS  基盤研究C 

    加藤亮

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    Grant type:Competitive

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  • 地域の有機性資源と鉄バクテリアを用いたリン資源の循環利用システム

    2008 - 2012

    JSPS  基盤研究B 

    武田育郎

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    Grant type:Competitive

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  • 気候変動による流域水環境の変化が汽水域の生物生息環境に及ぼす影響評価に関する研究

    2008 - 2009

    JSPS  若手研究B 

    宗村広昭

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    Authorship:Principal investigator  Grant type:Competitive

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  • 熱帯アジア(インドネシア)における集水域生態系の持続的利用と農業生産

    2006 - 2008

    JSPS  基盤研究B 

    増永二之

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    Grant type:Competitive

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  • 水田地域における生物生息環境保全のための水土環境診断システム

    2004 - 2007

    JSPS  基盤研究B 

    武田育郎

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    Grant type:Competitive

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  • 流域水資源管理*半乾燥地における水資源の有効利用と農業生産の安定化に関する研究

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    Grant type:Competitive

    アフガニスタンにおいて,流域における水資源の確保・有効利用と農業生産(特に麦)の安定化を目指して,水資源量(灌漑水量)に関する解析や将来的な気候の変化による水資源量の変化に関する解析を,アフガニスタンからの留学生と共に行っている.

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  • 流域水環境管理*流域環境の変化が生物生息環境に与える影響*営農など人間活動が流域水環境へ及ぼす影響*河川流域が下流湖沼の水文・水質環境に及ぼす影響*コハクチョウの越冬が冬期湛水水田の水環境に与える影響と営農コスト削減効果に関する研究

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    Grant type:Competitive

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  • Modeling Analysis of NO3-N pollution Processes of Groundwater.

    0100 (Japanese Only) 

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    Grant type:Competitive

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  • 流域水資源管理*半乾燥地における水資源の有効利用を通した農業生産の安定化と河川生態系保全に関する研究

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    Grant type:Competitive

    アフリカ・モザンビーク・リンポポ川流域において,特に乾期の灌漑水量の確保・食糧生産の安定化と環境用水・生態系保全とのバランス(最適管理)に関する研究を,モザンビークから来た留学生と共に開始している.

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Class subject in charge

  • Programming (2023academic year) 3rd and 4th semester  - 水1~2

  • Programming (2023academic year) 3rd and 4th semester  - 水1~2

  • Programming (2023academic year) 3rd and 4th semester  - 水1~2

  • Programming 1 (2023academic year) Third semester  - 水1~2

  • Programming 2 (2023academic year) Fourth semester  - 水1~2

  • Chemical Analyses in Environmental Science (2023academic year) Year-round  - その他

  • International Field Sciences (2023academic year) Year-round  - その他

  • Atmospheric Environment (2023academic year) Second semester  - その他

  • Laboratory Work and Practice on Basic Engineering (2023academic year) 1st and 2nd semester  - 火5~8

  • Laboratory Water Management (2023academic year) 1st semester  - 月5~7,木5~7

  • Laboratory Water Management (2023academic year) 1st semester  - 月5~7,木5~7

  • Hydraulics and Exercise (2023academic year) 3rd and 4th semester  - [第3学期]木5~6, [第4学期]木5~8

  • Water Resources Management (2023academic year) Prophase  - 火1~2

  • Introduction of Fluid Dynamics (2023academic year) 3rd and 4th semester  - [第3学期]木5~6, [第4学期]木5~8

  • Advanced Watershed management (2023academic year) Late  - その他

  • Advanced Study (2023academic year) Other  - その他

  • Special Research (2023academic year) Year-round  - その他

  • Special Research (2023academic year) Other  - その他

  • Environmental Meteorology (2023academic year) Second semester  - 水3~4,木3~4

  • Environmental Meteorology (2023academic year) Second semester  - 水3~4,木3~4

  • Irrigation and Environmental Biophysics (2023academic year) Late  - その他

  • Practices in Statistics and Numerical Analyses (2023academic year) Year-round  - その他

  • Academic Paper Writing (2023academic year) Late  - その他

  • Rural and Environmental Meteorology (2023academic year) Prophase  - 火2~3

  • Seminar on Irrigation and Drainage (2023academic year) Prophase  - その他

  • Seminar in Irrigation and Drainage (2023academic year) Late  - その他

  • Seminar on Irrigation and Drainage (2023academic year) Late  - その他

  • Seminar in Irrigation and Drainage (2023academic year) Prophase  - その他

  • Seminar on water resources management B (2023academic year) Year-round  - その他

  • Seminar in Irrigation and Drainage (2023academic year) Prophase  - その他

  • Programming (2022academic year) 3rd and 4th semester  - 水1~2

  • Programming (2022academic year) 3rd and 4th semester  - 水1~2

  • Programming 1 (2022academic year) Third semester  - 水1~2

  • Programming 2 (2022academic year) Fourth semester  - 水1~2

  • Laboratory Work and Practice on Basic Engineering (2022academic year) 1st and 2nd semester  - 火5~8

  • Laboratory Water Management (2022academic year) 1st semester  - 月5~7,木5~7

  • Hydraulics and Exercise (2022academic year) 3rd and 4th semester  - [第3学期]木5~6, [第4学期]木5~8

  • Introduction of Fluid Dynamics (2022academic year) 3rd and 4th semester  - [第3学期]木5~6, [第4学期]木5~8

  • Special Research (2022academic year) Other  - その他

  • Special Research (2022academic year) Year-round  - その他

  • Environmental Meteorology (2022academic year) Second semester  - 水3~4,木3~4

  • Environmental Meteorology (2022academic year) Second semester  - 水3~4,木3~4

  • Irrigation and Environmental Biophysics (2022academic year) Late  - その他

  • Rural and Environmental Meteorology (2022academic year) Prophase  - 火2~3

  • Rural and Environmental Meteorology (2022academic year) Prophase  - その他

  • Seminar on Irrigation and Drainage (2022academic year) Prophase  - その他

  • Seminar in Irrigation and Drainage (2022academic year) Late  - その他

  • Seminar on Irrigation and Drainage (2022academic year) Late  - その他

  • Seminar in Irrigation and Drainage (2022academic year) Prophase  - その他

  • Laboratory in Water Management (2021academic year) 1st semester  - 月5,月6,月7,木5,木6,木7

  • Programming (2021academic year) 3rd and 4th semester  - 水1,水2

  • Programming (2021academic year) 3rd and 4th semester  - 水1,水2

  • Programming 1 (2021academic year) Third semester  - 水1,水2

  • Programming 2 (2021academic year) Fourth semester  - 水1,水2

  • Laboratory Work and Practice on Basic Engineering (2021academic year) 1st and 2nd semester  - 火5,火6,火7,火8

  • Laboratory Water Management (2021academic year) 1st semester  - 月5~7,木5~7

  • Introduction of Fluid Dynamics (2021academic year) Fourth semester  - 火5~6,金5~6

  • Special Research (2021academic year) Year-round  - その他

  • Biosphere and Ecosystem (2021academic year) Second semester  - 火1~2,金3

  • Biosphere and Ecosystem (2021academic year) Second semester  - 火1~2,金3

  • Environmental Meteorology (2021academic year) Second semester  - 木1~3

  • Irrigation and Environmental Biophysics (2021academic year) Late  - その他

  • Rural and Environmental Meteorology (2021academic year) Prophase  - 火2~3

  • Seminar on Irrigation and Drainage (2021academic year) Prophase  - その他

  • Seminar in Irrigation and Drainage (2021academic year) Late  - その他

  • Seminar on Irrigation and Drainage (2021academic year) Late  - その他

  • Seminar in Irrigation and Drainage (2021academic year) Prophase  - その他

  • Laboratory in Water Management (2020academic year) 1st semester  - 月5,月6,月7,木5,木6,木7

  • Introduction to Innovation (2020academic year) Late  - 月7,月8,金7,金8

  • Introduction to Innovation (2020academic year) Late  - 月7~8,金7~8

  • Laboratory Water Management (2020academic year) 1st semester  - 月5,月6,月7,木5,木6,木7

  • Laboratory Water Management (2020academic year) 1st semester  - 月5,月6,月7,木5,木6,木7

  • Introduction of Fluid Dynamics (2020academic year) Fourth semester  - 火4,火5,金4,金5

  • Introduction of Fluid Dynamics (2020academic year) Fourth semester  - 火4,火5,金4,金5

  • Special Research (2020academic year) Year-round  - その他

  • Biosphere and Ecosystem (2020academic year) Second semester  - 火1,火2,金3

  • Biosphere and Ecosystem (2020academic year) Second semester  - 火1,火2,金3

  • Environmental Meteorology (2020academic year) Second semester  - 火6,火7,火8

  • Environmental Meteorology (2020academic year) Second semester  - 火6,火7,火8

  • Irrigation and Environmental Biophysics (2020academic year) Late  - その他

  • Rural and Environmental Meteorology (2020academic year) Prophase  - 火2,火3

  • Seminar on Irrigation and Drainage (2020academic year) Prophase  - その他

  • Seminar in Irrigation and Drainage (2020academic year) Late  - その他

  • Seminar on Irrigation and Drainage (2020academic year) Late  - その他

  • Seminar in Irrigation and Drainage (2020academic year) Prophase  - その他

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Social Activities

  • テーマ探究:キックオフセミナー(理系)

    Role(s):Lecturer

    笠岡高校  探究活動キックオフセミナー  オンライン  2021.4.14

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    Audience: High school students

    Type:Visiting lecture

  • 学生・職員・教員が共に考え活動する岡山大学 SDGs の取り組み

    Role(s):Lecturer

    山口大学,公益社団法人日本水環境学会中国・四国支部地域分科会  第 58 回水環境フォーラム山口  2021.9.25

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    Type:Lecture

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  • 「テーマ探究」キックオフセミナー(理系)

    Role(s):Lecturer

    笠岡高校(オンライン接続)  2021.4.14

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    Type:Visiting lecture

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