Faculty Profiles - SUDO Miki

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水環境中に残留する水田施用農薬のPolar Organic Chemical Integrative Sampler（ POCIS）とグラブサンプリングによる時間加重平均濃度の比較 Reviewed

須戸幹、梶原暢人、岩間憲治

水環境学会誌 45 ( 2 ) 41 - 50 2022

水環境中に残留する水田施用農薬のPolar Organic Chemical Integrative Sampler（ POCIS）とグラブサンプリングによる時間加重平均濃度の比較 Reviewed

須戸幹, 梶原暢人, 岩間憲治

水環境学会誌 45 ( 2 ) 41 - 50 2022

Hexabromocyclododecane in riverine and estuarine sediments from Osaka, Japan: spatial distribution and concentration variability within identical samples Reviewed

Ichihara M., Yamamoto A., Kakutani N., Funasaka K., Sudo M.

Environmental Science and Pollution Research 27 ( 28 ) 35782 - 35791 2020.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Environmental Science and Pollution Research

In this study, hexabromocyclododecane (HBCD) in riverine and estuarine sediments was investigated in Osaka, Japan. The mean total HBCD concentration detected in sediments ranged from < 0.50 to 130 ng g dry weight. This exceeded the ubiquitous HBCD contamination level found globally but was lower than that in areas affected by point sources, such as textile industries and expanded polystyrene plants. Sewage effluent was one of the suspected point sources of HBCD in the study area. The HBCD concentrations in sediments were highly dependent on certain factors, such as the location of the sampling site (proximity to possible emission sources), sediment properties (silt or sand), and organic substance content. The range of the diastereomer composition of α- and γ-HBCD was wider than that in other studies. Repeatability tests (n = 3) were conducted for all samples to assess the variability in the HBCD concentrations within identical sediment samples. Some variations were observed in the HBCD concentrations and diastereomer compositions within the repeatability test results at some sampling sites; nevertheless, the same samples were extracted and analyzed in triplicate. The bromine contents of the extracts of these samples were analyzed by X-ray fluorescence, and the results agreed well with those estimated from the LC-MS/MS results. From these results, it was confirmed that several sediment samples contained heterogeneously distributed HBCD. The risk characterization ratios (predicted environmental concentration/predicted no-effect concentration) of sites with high HBCD concentrations ranged from 0.1 to 1; thus, further information is required, and the sediment HBCD levels in this region should be continuously studied. −1

DOI： 10.1007/s11356-020-09856-0

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Inhomogeneity of sediment samples in analysis of hexabromocyclododecane Reviewed

Ichihara M., Yamamoto A., Kakutani N., Takakura K., Sudo M.

Environmental Monitoring and Assessment 191 ( 7 ) 2019.7

Language：English Publishing type：Research paper (scientific journal) Publisher：Environmental Monitoring and Assessment

© 2019, Springer Nature Switzerland AG. The repeatability test of the analytical method for hexabromocyclododecane (HBCD) was conducted with sediment sample. The maximum HBCD concentration exceeded the minimum by a factor of 90 even though the identical sediment samples were used. Therefore, we examined which step of the analytical method was the factor causing variability. We examined the blank test, and confirmation test of the extraction and purified procedure. From these results, we confirmed that there was nothing wrong with the accuracy of our analytical method. These results indicate that the variability of HBCD concentration in the repeatability test was attributed not to the analytical method, but to the inhomogeneity of the sediment sample. Aluminum, silicon, and organic carbon in sediments were measured to compare the variability of these concentrations with that of HBCD concentration. These concentrations were similar values within identical samples which showed variability in HBCD concentration. HBCD concentration in several samples did not correlate with organic carbon content. These results suggests that sediment samples were homogeneous by itself, and HBCD was heterogeneously distributed in spite of homogeneity of organic carbon in sediment. The sediment sample with variability in HBCD concentration showed different HBCD diastereomer compositions in identical sediment. It implies that the sample contained HBCD derived from different histories or point sources. Even though we increased sample amounts to analyze the homogeneity of the sample, HBCD concentration varied within identical samples if the sample had a hot spot. Past monitoring data may contain overestimation or underestimation of HBCD concentration in sediment.

DOI： 10.1007/s10661-019-7553-6

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Inhomogeneity of sediment samples in analysis of hexabromocyclododecane Reviewed

Ichihara M, Yamamoto A, Kakutani N, Takakura K, Sudo M

Environmental Monitoring and Assessment 191 ( 7 ) 2019.7

Language：English Publishing type：Research paper (scientific journal) Publisher：Environmental Monitoring and Assessment

DOI： 10.1007/s10661-019-7553-6

農薬の農耕地から河川への流出に関する研究 Invited

須戸幹

水環境学会誌 42A ( 11 ) 381 - 385 2019

農薬の農耕地から河川への流出に関する研究 Invited

須戸幹

水環境学会誌 42A ( 11 ) 381 - 385 2019

Uptake and elimination kinetics of trifluralin and pendimethalin in Pheretima spp. and Eisenia spp. Reviewed

Goto Y., Sudo M.

Environmental Science and Pollution Research 25 ( 13 ) 12352 - 12360 2018.5

Language：English Publishing type：Research paper (scientific journal) Publisher：Environmental Science and Pollution Research

© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. The purpose of this study was to clarify the kinetic bioaccumulation potential of herbicides in the earthworm, Pheretima spp., the most common earthworms throughout Asia, and Eisenia spp., litter-feeding earthworms included in the test species recommended by the Organization for Economic Co-operation and Development. The kinetic bioaccumulation factors of trifluralin and pendimethalin were estimated from an uptake test for 10 or 12 days and from an elimination test for 10 days. The time required to reach a steady state following herbicide exposure was 7 days for both herbicides in Eisenia spp. and 1 day in Pheretima spp. The uptake rate constant (g-soil/g-worm/day) and elimination rate constant (per day) for trifluralin were 2.1 and 0.23 in Eisenia spp. and 0.42 and 0.45 in Pheretima spp., respectively, and those for pendimethalin were 1.5 and 0.26 in Eisenia spp. and 0.27 and 1.0 in Pheretima spp., respectively. Kinetic bioaccumulation factors of both herbicides were relatively close to bioaccumulation factors in steady state and were higher in Eisenia spp. (8.9 for trifluralin and 5.7 for pendimethalin) than in Pheretima spp. (0.95 and 0.26). These results demonstrated that the herbicide bioaccumulation risk is lower for Pheretima spp. than for Eisenia spp. because of the lower uptake rate and higher elimination rate in Pheretima spp.

DOI： 10.1007/s11356-018-1483-7

Uptake and elimination kinetics of trifluralin and pendimethalin in Pheretima spp. and Eisenia spp. Reviewed

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Yuko Goto, Miki Sudo

Environmental Science and Pollution Research 25 ( 13 ) 12352 - 12360 2018.5

Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Verlag

The purpose of this study was to clarify the kinetic bioaccumulation potential of herbicides in the earthworm, Pheretima spp., the most common earthworms throughout Asia, and Eisenia spp., litter-feeding earthworms included in the test species recommended by the Organization for Economic Co-operation and Development. The kinetic bioaccumulation factors of trifluralin and pendimethalin were estimated from an uptake test for 10 or 12 days and from an elimination test for 10 days. The time required to reach a steady state following herbicide exposure was 7 days for both herbicides in Eisenia spp. and 1 day in Pheretima spp. The uptake rate constant (g-soil/g-worm/day) and elimination rate constant (per day) for trifluralin were 2.1 and 0.23 in Eisenia spp. and 0.42 and 0.45 in Pheretima spp., respectively, and those for pendimethalin were 1.5 and 0.26 in Eisenia spp. and 0.27 and 1.0 in Pheretima spp., respectively. Kinetic bioaccumulation factors of both herbicides were relatively close to bioaccumulation factors in steady state and were higher in Eisenia spp. (8.9 for trifluralin and 5.7 for pendimethalin) than in Pheretima spp. (0.95 and 0.26). These results demonstrated that the herbicide bioaccumulation risk is lower for Pheretima spp. than for Eisenia spp. because of the lower uptake rate and higher elimination rate in Pheretima spp.

DOI： 10.1007/s11356-018-1483-7

Herbicide discharge from rice paddy fields by surface runoffand percolation flow: A case study in paddy fields in the Lake Biwa basin, Japan Reviewed

Sudo M., Goto Y., Iwama K., Hida Y.

Journal of Pesticide Science 43 ( 1 ) 24 - 32 2018.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Pesticide Science

© Pesticide Science Society of Japan. The transport of three herbicides, pyriminobac-methyl, imazosulfuron and pyraclonil from a watershed that includes 40 ha of paddy fields to a drainage canal was monitored in the Lake Biwa basin, Japan. Based on the intensive monitoring of all paddy plots and in the drainage canal conducted on 3 days during and after the application period, the passage of herbicide discharge from the paddy fields to the drainage canal was separated into surface runoffobtained from field observations and percolation flow calculated from the herbicide mass balance. Surface runofffrom paddy plots immediately after herbicide application, discharging a large volume of paddy water, or both processes in conjunction had a significant effect on herbicide discharge. Without surface runoff, paddy fields discharged a consistently high amount of herbicide gradually by percolation flow. These results suggest that considerable amounts of herbicides were discharged into the drainage canal through percolation even if appropriate water management to prevent herbicide surface runoffwas practiced.

DOI： 10.1584/JPESTICS.D17-061

Herbicide discharge from rice paddy fields by surface runoffand percolation flow: A case study in paddy fields in the Lake Biwa basin, Japan Reviewed

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Sudo M, Goto Y, Iwama K, Hida Y

Journal of Pesticide Science 43 ( 1 ) 24 - 32 2018.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Pesticide Science

DOI： 10.1584/jpestics.D17-061

A Bayesian approach for estimating hexabromocyclododecane (HBCD) diastereomer compositions in water using data below limit of quantification Reviewed

Ichihara M., Yamamoto A., Kakutani N., Sudo M., Takakura K.

Environmental Science and Pollution Research 24 ( 3 ) 2667 - 2674 2017.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Environmental Science and Pollution Research

© 2016, Springer-Verlag Berlin Heidelberg. We developed a statistical model that quantitatively incorporated the stochastic fluctuations of values, which were estimated as Bayesian credible intervals (BCIs), to analyze environmental monitoring data. We used α-hexabromocyclododecane (α-HBCD) diastereomer compositions of water samples that included data points below limit of quantification. To avoid replacing “not detected (ND)” values with irrelevant values in data analysis, we substituted ND with observed values from the measurement system upon examination of the model. In our study, it was assumed that the magnitude of stochastic fluctuations of observed values in environmental samples was identical to that in iterative measurements of a standard solution at the lowest concentration. Using this model, α-HBCD diastereomer compositions could be estimated along with BCIs even for samples collected from sites where concentrations of α-HBCD were ND or near limit of quantification. The brackish areas in our study showed relatively wide ranges in composition for the 95% BCIs compared with samples from fresh water areas. In the brackish areas, concentrations of HBCD were frequently ND or near limit of quantification. Using this model, it was unnecessary to replace ND with zero or limit of quantification in data analysis, and an environmental assessment could be achieved using all of the data. Therefore, this model is considered to be a widely applicable approach in the analysis of environmental monitoring data including ND.

DOI： 10.1007/s11356-016-7990-5

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A Bayesian approach for estimating hexabromocyclododecane (HBCD) diastereomer compositions in water using data below limit of quantification Reviewed

Makiko Ichihara, Atsushi Yamamoto, Naoya Kakutani, Miki Sudo, Koh-ichi Takakura

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 24 ( 3 ) 2667 - 2674 2017.1

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER HEIDELBERG

We developed a statistical model that quantitatively incorporated the stochastic fluctuations of values, which were estimated as Bayesian credible intervals (BCIs), to analyze environmental monitoring data. We used alpha-hexabromocyclododecane (alpha-HBCD) diastereomer compositions of water samples that included data points below limit of quantification. To avoid replacing "not detected (ND)" values with irrelevant values in data analysis, we substituted ND with observed values from the measurement system upon examination of the model. In our study, it was assumed that the magnitude of stochastic fluctuations of observed values in environmental samples was identical to that in iterative measurements of a standard solution at the lowest concentration. Using this model, alpha-HBCD diastereomer compositions could be estimated along with BCIs even for samples collected from sites where concentrations of alpha-HBCD were ND or near limit of quantification. The brackish areas in our study showed relatively wide ranges in composition for the 95% BCIs compared with samples from fresh water areas. In the brackish areas, concentrations of HBCD were frequently ND or near limit of quantification. Using this model, it was unnecessary to replace ND with zero or limit of quantification in data analysis, and an environmental assessment could be achieved using all of the data. Therefore, this model is considered to be a widely applicable approach in the analysis of environmental monitoring data including ND.

DOI： 10.1007/s11356-016-7990-5

A Bayesian approach for estimating hexabromocyclododecane (HBCD) diastereomer compositions in water using data below limit of quantification Reviewed

Makiko Ichihara, Atsushi Yamamoto, Naoya Kakutani, Miki Sudo, Koh-ichi Takakura

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 24 ( 3 ) 2667 - 2674 2017.1

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER HEIDELBERG

DOI： 10.1007/s11356-016-7990-5

水田からの窒素、リン、COD流出負荷量能実態と課題 Reviewed

治多伸介、須戸幹　他

水環境学会誌 38 ( 4 ) 81 - 91 2015

Effluent N, P and COD Loads from Paddy Fields in Japan: A Critical Review Reviewed

HARUTA Shinsuke, SUDO Miki, EGUCHI Sadao, OKUBO Takuya, KURODA Hisao, TAKEDA Ikuo, FUJIWARA Taku, YAMAMOTO Tadao, HITOMI Tadayoshi, SHIRATANI Eisaku, YOKOTA Kuriko, INOUE Takanobu

Japan journal of water pollution research 38 ( 4 ) 81 - 91 2015

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society on Water Environment

While the effluent pollutant loads of nitrogen, phosphorus, and COD from paddy fields are very important basic figures in a wide variety of environmental planning and research tasks, more reliable figures have been required. In this paper, the database of the pollutant load from paddy fields in Japan, established by the authors, is explained and the analytical results and future issues are presented. The database is based on the 72 references published since 1980s and it includes 467 data sets of the pollutant loads and information on the references, and investigation and farming conditions. The investigation of the irrigation season and the verification of the effects of the wide variety of improved farming methods during the irrigation season have been conducted in Japan. However, data for nonirrigation season and specific data obtained in paddy fields cultivated using variety of farming methods will be needed. The verification of the effects of the improved farming methods in the nonirrigation season and the development of the best management practices for the reduction of the pollutant load in the nonirrigation season are also required. The figures for phosphorus and COD adopted for the Seventh Total Water Pollutants Reduction Plan and the water conservation plan for selected lakes are much lower than the average values for by conventional farming methods available in the database. Therefore, the values for the Seventh Total Water Pollutants Reduction Plan will be revised referring to our database. The pollutant load from a paddy field cultivated by custom farming decreased with the decrease in the amount of fertilizer used. Thus, the recent data will be of great value. Other countries are facing a shortage of the data on pollutant loads in paddy fields. In the countries, there is a lack of experience in improving methods of farming to reduce the pollutant loads in paddy fields. Therefore, our database will be useful for other countries. The database is available on the web, and it is expected to contribute to future governmental and research activities.

DOI： 10.2965/jswe.38.81

Other Link： https://jlc.jst.go.jp/DN/JLC/20012936012?from=CiNii

Distribution and pollutant load of hexabromocyclododecane (HBCD) in sewage treatment plants and water from Japanese Rivers Reviewed

Makiko Ichihara, Atsushi Yamamoto, Koh-ichi Takakura, Naoya Kakutani, Miki Sudo

CHEMOSPHERE 110 78 - 84 2014.9

Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD

Hexabromocyclododecane diastereoisomers (alpha-, beta-, gamma-, delta-, and epsilon-HBCD) were investigated in river water, sewage influent, and sewage effluent from the Yodo River basin, Japan. The mean annual values of HBCDs ranged from 0.19 to 14 ng L-1 in river water. We observed that the concentrations of HBCDs in the brackish water area were low compared with that in the fresh water area. It was implied that, when the flow of the river stagnated in the estuarine area, HBCDs settled with suspended matter because of their hydrophobic character. In the sewage treatment plants, HBCDs ranged from 16 to 400 ng L-1 in sewage influent, whereas they ranged from 0.39 to 12 ng L-1 in sewage effluent. Over 90% of HBCDs were removed from the wastewater in the sewage treatment plants. By using these results, we estimated the pollutant load of HBCDs that flows into Osaka Bay from the study area. It was estimated that approximately 15 kg of HBCDs flow into Osaka Bay from the study area in a year. This value is five orders of magnitude lower than the 2010 market demand for HBCDs (3019 metric tons) in Japan. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.chemosphere.2014.03.074

An Attempt to Create Depths for Fish Wintering in an Agricultural Canal during a Non-irrigation Period Reviewed

Distribution and pollutant load of hexabromocyclododecane (HBCD) in sewage treatment plants and water from Japanese Rivers Reviewed

Makiko Ichihara a, Atsushi Yamamoto, Koh-ichi Takakura, Naoya Kakutani, Miki Sudo

Chemosphere 110 78 - 84 2014

A. Minagawa, K. Takaki, M. Sudo, OH. Odani, K. Iwama, R. Kaneki

Irrigation, Drainage and Rural Engineering Journal 80 ( 5 ) 445 - 454 2012

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

The following 3 types of depths were created to investigate the effects on wintering fish in an agricultural canal: (1) a 30-cm-deep dammed section of the canal; (2) a 60-cm -deep hand-dug section of the canal that was covered; and (3) a 60-cm-deep hand-dug section of the canal that was left uncovered. The number of fish species, fish density and the diversity index were compared at each sampling station during the same months the previous year.<br>The 3 above-mentioned parameters showed increased values after the depths were created. Fish density in the covered 60-cm-deep section was higher than that in the 60-cm-deep section with no cover. Moreover, the fish marked previously in the mark and recapture method either remained at the same depth or moved from a depth with no cover to a covered depth. Therefore, the depth with a cover could be especially effective for fish wintering. Consequently, bank trees, overhead banks, and submerged plants should be conserved as a cover for wintering fish.

DOI： 10.11408/jsidre.80.445

Other Link： https://jlc.jst.go.jp/DN/JALC/10024829990?from=CiNii

A difference of the herbicide bioaccumulation between two species of earthwarm, Eisenia cf. fetida and Pheretima spp.. Reviewed

Y. Goto and M. Sudo

The Japanese Society of Environmental Entomology and Zoology 23 ( 1 ) 19 - 25 2012

An Attempt to Create Depths for Fish Wintering in an Agricultural Canal during a Non-irrigation Period Reviewed

A. Minagawa, K. Takaki, M. Sudo, OH. Odani, K. Iwama and R. Kaneki

Irrigation, Drainage and Rural Engineering Journal 80 ( 5 ) 445 - 454 2012

Effect of percolation flow on herbicide loss from rice paddies Reviewed

Miki Sudo, Yuko Goto, Takahiro Okajima, Rieko Horiuchi and Hiromichi Odani

Journal of Pesticide Science 37 ( 2 ) 140 - 147 2012

Effect of percolation flow on herbicide loss from rice paddies Reviewed

Miki Sudo, Yuko Goto, Takahiro Okajima, Rieko Horiuchi, Hiromichi Odani

JOURNAL OF PESTICIDE SCIENCE 37 ( 2 ) 140 - 147 2012

Language：English Publishing type：Research paper (scientific journal) Publisher：PESTICIDE SCI SOC JAPAN

The fate and transport of pretilachlor, one of the most widely used rice-paddy herbicides in Japan, were monitored in a rice paddy plot for 28 days after its application in the five study years. The effect of the percolation rate on herbicide loss was investigated. The concentration of pretilachlor in the paddy water was at its highest level within 2 days of application. The maximum concentration in percolated water was lower, and it was reached 1 or 2 days later than that in the paddy water. Almost all the pretilachlor loss was caused by percolation. The pretilachlor loss, as estimated from the amount that was applied and the cumulative percolation loss, ranged from 7.4 to 16.3%. In the five study years, the average percolation rate for the 7 days following application ranged from 11.5 to 29.3 mm/day. The pretilachlor loss increased proportionally with the percolation rate for 7 days following application. (c) Pesticide Science Society of Japan

DOI： 10.1584/jpestics.D11-032

A difference of the herbicide bioaccumulation between two species of earthwarm, Eisenia cf. fetida and Pheretima spp.. Reviewed

Y. Goto, M. Sudo

The Japanese Society of Environmental Entomology and Zoology 23 ( 1 ) 19 - 25 2012

The Effect of Subsurface Water Flow on Herbicide Concentrations and Loads in the Stream Water Reviewed

Y. Goto, M. Sudo, Y. Hida and H. Odani

Irrigation, Drainage and Rural Engineering Journal 275 59 - 68 2011

The Effect of Subsurface Water Flow on Herbicide Concentrations and Loads in the Stream Water Reviewed

Y. Goto, M. Sudo, Y. Hida, H. Odani

Irrigation, Drainage and Rural Engineering Journal 275 ( 5 ) 59 - 68 2011

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

The purpose of this study is to evaluate the effect of subsurface water flow on herbicide residues in stream water. Pesticide concentrations and loads were monitored three times in Yasu River and twice in Hino River from May to June 2005. Surface water always flowed and reached to river mouth in Hino River, although infiltration of all of the surface water was observed in some part of the Yasu River channel. Pesticide concentrations returned to the surface streams were < 1/100 lower than that of surface water before infiltration. Possible reason may be the dilution and diffusion with shallow ground water and/or lake water. Runoff coefficient at the end of receiving stream was calculated to 1.0 for Hino River and 0.01 - 0.1 for Yasu River.

DOI： 10.11408/jsidre.79.375

Effects for Effluent Loads and Mass Balance of Paddy Fields with Reduction of Fertilizxer and Non-puddled Cultibation Reviewed

Other Link： https://jlc.jst.go.jp/DN/JALC/10010471134?from=CiNii

Effects for Effluent Loads and Mass Balance of Paddy Fields with Reduction of Fertilizxer and Non-puddled Cultibation Reviewed

R. Kaneki, N. Furukawa, J Yamaguchi, K. Iwama, H. Odani and M. Sudo

Japan Society of Hydrology and Water Resources 23 ( 3 ) 216 - 230 2010

R. Kaneki, N. Furukawa, J Yamaguchi, K. Iwama, H. Odani, M. Sudo

Japan Society of Hydrology and Water Resources 23 ( 3 ) 216 - 230 2010

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

The effects of reducing fertilizer and non-puddled cultivation on outflow loads from paddy fields, water purification and mass balance were examined for four years. Four experimental plots were set up for comparison. <BR>As a result, the levels of surface effluent loads of the plots with single application of fertilizer in nursery box were reduced 64 % for T-N and 51 % for T-P as compared with the plots that used conventional fertilizer. The reduced level of subsurface effluent loads of the plots were 26 % for D-N and 23 % for D-P. SS, COD, T-N and T-P surface runoff loads from the non-puddled divisions were reduced 71 %, 59 %, 41 %, and 48 % respectively as compared with those of the puddled divisions. For water purification, non-puddled cultivation appeared to be effective in reducing the effluent loads, because there were significant differences in SS, COD, and P. Additionally, interaction between the puddling methods and fertilizing methods showed significant differences in N. Both nitrogen and phosphorous collected from incoming factors such as irrigation, rain and fertilizer were greater than those of outgoing factors such as surface effluent load, subsurface effluent load and hulled rice because of the use of too much fertilizer.

DOI： 10.3178/jjshwr.23.216

Herbicide Discharge from Paddy Fields Located Around Lake Biwa Basin and Development of Simple Model for Estimation of Herbicide Loss Reviewed

Other Link： https://jlc.jst.go.jp/DN/JALC/00351090118?from=CiNii

代かき・移植時における水田からの農業濁水発生機構 Reviewed

須戸幹，三木俊和，伊庭一磨，増田佳昭

農業土木学会論文集 260 ( － ) 7 - 13 2009.4

代かき・移植時における水田からの農業濁水発生機構 Reviewed

須戸幹, 三木俊和, 伊庭一磨, 増田佳昭

農業土木学会論文集 260 ( - ) 7 - 13 2009.4

琵琶湖集水域水田群における除草剤の流出と流出率予測簡易モデルの開発 Reviewed

川嵜悦子，大久保卓也，須戸幹

水環境学会誌 31 ( － ) － - － 2008.4

「環境こだわり農業」が水稲栽培の農薬流出負荷に与える効果 Reviewed

須戸　幹，蓮川博之，柴原藤善

用水と廃水 50 ( 3 ) 54 - 62 2008.4

「環境こだわり農業」が水稲栽培の農薬流出負荷に与える効果 Reviewed

須戸幹, 蓮川博之, 柴原藤善

用水と廃水 50 ( 3 ) 54 - 62 2008.4

KAWASAKI Etsuko, OKUBO Takuya, SUDO Miki

Japan journal of water pollution research 31 ( - ) - - - 2008.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society on Water Environment

The concentrations and loadings of herbicides were investigated in paddy fields (40.5ha) located around Lake Biwa from May to October in 2005 and 2006. The herbicide losses from the basin determined from the cumulative load from May to July and the application amount determined by the questionnaire method by Japan Agricultural Cooperatives (JA) were estimated in 2005 and 2006, respectively, to be 26.3% and 36.5% for Daimuron, 24.5% and 30.8% for Bomobutide, 21.5% and 18.6% for Simetryn, 15.7% and 9.30% for Benfresate, 9.14% and 11.3% for Pretilachlor, 5.49% and 5.33% for Mefenacet, and 0.32% and 0.84% for Esprocarb, and in 2005 to be 5.52% for Thenylchlor and 4.74% for Cafenstrol. A Simple model was developed to estimate herbicide losses by multiple regression analysis. The specific loss, which is calculated from the total loss and the average discharge on nonrainy days, was used as the criterion variable. The water solubility, Henry's law constant and soil adsorption constant were used as explanatory variables. The most important contributor to herbicide losses is the adsorption constant of soil. The specific losses calculated from the result of multiple regression analysis were consistent with the observed values. The errors between the observed and calculated values were within ± 0.5% for four herbicides and almost ± 1.0% for five herbicides.

DOI： 10.2965/jswe.31.375

Other Link： https://jlc.jst.go.jp/DN/JALC/00316469560?from=CiNii

琵琶湖の植物プランクトン成長に及ぼす農業排水の影響評価の試み Reviewed

木村成子，伴修平，吉川徹，須戸幹

陸水学会誌 68 ( 3 ) 403 - 413 2007.4

琵琶湖の植物プランクトン成長に及ぼす農業排水の影響評価の試み Reviewed

木村成子, 伴修平, 吉川徹, 須戸幹

陸水学会誌 68 ( 3 ) 403 - 413 2007.4

Comparison of the effects of di(2-ethylhexyl)phthalate, a peroxisome proliferator, on the vitamin metabolism involved in the energy formation in rats fed with a casein or gluten diet Reviewed

Katsumi Shibata, Tsutomu Fukuwatari, Yoriko Iguchi, Yuko Kurata, Miki Sudo, Ryuzo Sasaki

BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 70 ( 6 ) 1331 - 1337 2006.6

Language：English Publishing type：Research paper (scientific journal) Publisher：TAYLOR & FRANCIS LTD

In order to find an alleviation method for the adverse effect of environmental endocrine disrupters, we studied the effects of the putative endocrine disrupter and peroxisome proliferator, di(2-ethylhexyl)phthalate (DEHP), on animal growth and vitamin metabolism. It is known that the effects of chemical compounds such as xenobiotics differ according to the dietary protein source. We compared the effects of dietary DEHP administration on rats fed with a diet containing milk casein or wheat gluten. The increased conversion ratio of tryptophan to nicotinamide by DEHP administration was significantly higher in the casein group than in the gluten group. We also investigated the effects of DEHP on the urinary excretion of other vitamins. DEHP administration resulted in decreased urinary excretion of vitamin B-1, vitamin B-2, and pantothenic acid.

DOI： 10.1271/bbb.50618

Herbicide Discharge from Paddy Fields Located Around Lake Biwa Basin and Factors Affecting Herbicide Losses Reviewed

琵琶湖流域の水田群における除草剤の流出とその要因 Reviewed

須戸幹，川地武

水環境学会誌 29 ( 11 ) 715 - 721 2006.4

Decrease in pesticide concentrations and affected factors in lagoons located around Lake Biwa. Reviewed

Sudo M, Nishino M and Okubo T

Water Science and Technology 53 ( 2 ) 131 - 138 2006.4

Long-term fluctuation and regional variation of nutrient loads from the atmosphere to lakes Reviewed

T. Kunimatsu and M. Sudo

Water Science & Technology 53 ( 2 ) 53 - 61 2006.4

Comparison of the Effects of Di(2-ethylhexyl)phthalate, a Peroxisome Proliferator, on the Vitamin Metabolism Involved in the Energy Formation in Rats Fed with a Casein or Gluten Diet Reviewed

Katsumi Shibata, Tsutomu Fukuwatari, Yoriko Iguchi, Yuko Kurata, Miki Sudo, and Ryuzo Sasaki

Biosci. Biothechnol. Biochem 70 ( 6 ) 1331 - 1337 2006.4

水田からの窒素・リン流出負荷の削減 Reviewed

金木亮一，須戸幹，芝原勉

水文・水資源学会誌 19 ( 5 ) 360 - 371 2006.4

SUDO Miki, KAWACHI Takeshi

Japan journal of water pollution research 29 ( 11 ) 715 - 721 2006.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society on Water Environment

The concentrations and loadings of herbicides were investigated in three paddy field basins (4.7, 4.7 and 9.3 ha) from May to August 2002. The herbicide losses from the basins determined from cumulative load and application amount gathered by the questionnaire method were estimated to be 1.6% and 26% for Bromobutide, 8.9∼27% for Cafenstrol, 0.1% for Dimepiperate, 1.1∼2.0% for Mefenacet, 10.2∼25% for Simetryn, 0.9% and 14% for Thenylchlor, and 0.1∼1.6% for Thiobencarb. One of the important factors attributed to the differences in herbicide loss among the basins was water discharge from the basins. To generalize them, specific herbicide losses were calculated from herbicide losses and the height of daily dry weather flow. The specific herbicide losses suggested that transport with percolated water is the main factor for Cafenstrol and Simetryn losses, although other factors such as interaction with soil and degradation in soil may have also contribute to Bromotutide, Mefenacet, Thenylchlor and Thiobencarb losses from the paddy field basins.

DOI： 10.2965/jswe.29.715

Other Link： https://jlc.jst.go.jp/DN/JALC/00288086338?from=CiNii

Reduction of Effluent Loads of Nitrogen and Phosphorus from Paddy Fields Reviewed

KANEKI Ryoichi, SUDO Miki, SHIBAHARA Tsutomu

JOURNAL OF JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES 19 ( 5 ) 360 - 371 2006.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

Effects of no-puddling culture and reducing fertilizer culture are examined for two years on outflow loads of nitrogen and phosphorus. Four paddy fields are used, these are called "no-puddling and reducing fertilizer division," "puddling and reducing fertilizer division," "no-puddling and conventional fertilizer division" and "puddling and conventional fertilizer division." In the reducing fertilizer divisions, nitrogen is treated into a nursery box, and phosphorus is treated by using a side fertilizer transplanter. In the conventional fertilizer divisions, fertilizer is broadcasted as usual.

DOI： 10.3178/jjshwr.19.360

Other Link： https://jlc.jst.go.jp/DN/JALC/00284176866?from=CiNii

Long-term fluctuation and regional variation of nutrient loads from the atmosphere to lakes Reviewed

T Kunimatsu, M Sudo

WATER SCIENCE AND TECHNOLOGY 53 ( 2 ) 53 - 61 2006

Language：English Publishing type：Research paper (scientific journal) Publisher：I W A PUBLISHING

The atmospheric depositions were collected by ordinary bulk-samplers mounted with a glass or polyethylene funnel of 30cm orifice. A long-term observation was carried out at a site (35 degrees 01'30"N, 135 degrees 58'07"E) in the urbanized area for 21 years since 1974. The annual volume-weighted average concentrations of total nitrogen (TN) and phosphorus (TP) were 1.02 +/- 0.30 and 0.031 +/- 0.015 mg1(-1), respectively, and the loading rates were 14.5 +/- 2.8 and 0.43 +/- 0.16 kg ha(-1) yr(-1). The rates neither had a relationship with the precipitation (1,492 343 mm yr(-1)) nor showed any diachronic tendencies. In order to obtain the loading rate of TN and TP within 10% uncertainty under the significant level of 0.01, there is no way but to continue the observation for seven and eleven years or more, respectively. In order to clarify the regional variation of the loading amounts of the depositions, the samplers were set at 12 sites distributing throughout the Kinki District for two years. The distance from northernmost (2322 mm yr(-1)) to southernmost (11242 mm yr(-1)) is about 150 km. The average loading rates of the 12 sites were 16.2 +/- 2.5 kg ha(-1) yr(-1) of TN and 0.730 +/- 0.247 kg ha(-1)yr(-1) of TP. The depositions of NO3-N, NH4-N, and TN as well as TP showed tendencies with distances neither from a big city nor from Japan Sea.

DOI： 10.2166/wst.2006.038

Decrease in herbicide concentrations and affected factors in lagoons located around Lake Biwa Reviewed

M Sudo, M Nishino, T Okubo

WATER SCIENCE AND TECHNOLOGY 53 ( 2 ) 131 - 138 2006

Language：English Publishing type：Research paper (scientific journal) Publisher：I W A PUBLISHING

The contamination levels and changes in the concentrations in four lagoons around Lake Biwa of paddy-use herbicide were studied. Four lagoons, Sone-numa (52 days of HIRT (hydraulic residence time) estimated from the lagoon volume and the average discharge at the outlet, 21 ha area), Yanagihira-ko (40 days, 5.0 ha), Noda-numa (11 days, 6.0 ha), and lba-naiko (2 days, 55.5 ha), were selected as monitoring sites. Intensive water sampling was carried out once a week from May to June at the outlet of each lagoon. Although twelve of the monitored herbicides were detected, the maximum concentrations did not exceed the guidelines for water-supply law in Japan. The relation between half-lives in herbicide concentrations and characteristics of a lagoon such as HRT and chlorophyll-a concentrations were examined. The shorter half-lives of herbicide concentrations in lagoons with shorter HRT means that replacement by influent water effectively decreased the pesticide concentrations. Shorter half-lives in lagoons with high chlorophyll-a concentrations between the lagoons with similar HIRT suggest that biological degradation during the residence time worked more efficiently in the lagoon with high chlorophyll-a concentrations.

DOI： 10.2166/wst.2006.046

Paddy herbicide inputs in the entire river inflow reaching Lake Biwa, Japan Reviewed

Miki Sudo, Takuya Okubo, Ryoichi Kaneki

Limnology 6 ( 2 ) 91 - 99 2005.8

Language：English Publishing type：Research paper (scientific journal) Publisher：The Japanese Society of Limnology

This study estimated the inputs of four paddy herbicides in the entire river inflow reaching Lake Biwa, the largest lake in Japan, which serves as a water resource for 14 million people. The Uso River and the Hino River, the main contaminated rivers among the inflow rivers, were selected as daily and hourly monitoring sites to provide data on the seasonal trends in the concentration and load of herbicides and to determine the effect of rainfall events on load. The monitoring was also performed four times in 15 inflow rivers. The total input to the lake was calculated from the loads during fine weather conditions and additional loads during rainfall events. The former based on the lumped load from the two rivers and by prorating for the 15 rivers, and the latter was estimated from the relation between precipitation and increased load rate. The annual losses of herbicide from the basin to Lake Biwa were estimated to be 14.5% for bromobutide, 3.0% for pretilachlor, 5.2% for molinate, and 8.8% for simetryn. The loads caused by rainfall events accounted for 9%-18% of the total annual loads. © The Japanese Society of Limnology 2005.

DOI： 10.1007/s10201-005-0145-x