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The effects of Thailand's Great Flood of 2011 on river sediment discharge in the upper Chao Phraya River basin,Thailand

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International Journal of Sediment Research 2015年第4期30卷 328-337页

作者： Butsawan Bidorn Seree Chanyotha Stephen A.Kish Joseph F.Donoghue Komkrit Bidorn Ruetaitip Mama department of Earth Ocean and Atmospheric ScienceFlorida State University department of Water Resources Engineering Chulalongkorn University department of Physics University of Central Florida Royal irrigation department

Severe flooding that occurred during the 2011 monsoon season in Thailand was the heaviest flooding in the past 50 *** rainfall over the northern part of Thailand,especially during July-August 2011,was150%higher than *** the flooding period,river flows of the four major Chao Phraya River tributaries（Ping,Wang,Yom,and Nan rivers）increased in the range of 1.4-5 times the average *** study examined the river sediment discharge of the four major rivers in the upper Chao Phraya River basin in *** four rivers are considered the main sources of sediment supply to the Chao Phraya *** surveys of the Ping,Wang,Yom,and Nan rivers were carried out in October 2011（during the Great Flood）and October 2012（one year after the flood）.Survey data included river cross sections,flow velocities,suspended sediment concentrations,and bed load transport in each *** of these data indicated that total sediment transport rates for the four main rivers during the flooding of2011 were 2.3-5.6 times higher than the average sediment discharge over 60 *** flood of 2011 significantly affected the sediment characteristics including the proportions of suspended and bed sediment loads in each river though in different *** rates of sediment transport per unit discharge for the Ping and Wang rivers dramatically increased during the 2011 flood,but the flooding had minimal effects on the sediment characteristics in the Yom and Nan *** amount of total sediment discharge in each river caused by the 2011 flooding varied between 0.3 and 1.6 ***,the bed load transport in these rivers varied between0%and 26%of the suspended sediment discharge.

关键词： Bedload Sediment discharge Sediment transport rates Upper Chao Phraya River basin Flooding

Distribution and tensile strength of Hornbeam （Carpinus betulus） roots growing on slopes of Caspian Forests, Iran

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Journal of Forestry Research 2009年第A2期20卷 105-110,I0001页

作者： Ehsan Abdi Baris Majnounian Hassan Rahimi Mahmud Zobeiri department of Forestry University ofTehran Karaj 31585-3314 Iran department of irrigation University ofTehran Karaj 31585-3314 lran

Biomechanical characteristics of the root system of hornbeam （Carpinus betulus） were assessed by measuring Root Area Ratio （RAR） values and tensile strength of root specimens of eight hornbeam trees growing on hilly terrain of Northern Iran. RAR values of the roots were obtained using profile trenching method at soil depth of the top 0.1 m. In total 123 root specimens were analyzed for tensile strength. Results indicate that in general, RAR decreases with depth, following a power function. The RAR values in up and down slopes have no significant statistical differences. In most cases, the maximum RAR values were located in soil depth of the top 0.1 m, with maximum rooting depth at about 0.75 m. The minimum and maximum RAR values along the profiles were 0.004% and 6.431% for down slope and 0.004% and 3.995% for up slope, respectively. The number of roots in the up and down slope trenches was not significantly different. In the same manner as for RAR, number of roots distributing with depth was satisfactorily approximated a power function. The penetration depths of above 90 percent of the roots were at soil depths of 50 cm and 60 cm for up and down slopes, respectively. Results of Spearman＇s bivariate correlation showed no significant correlation between the RAR value with tree diameter and gradient of slope and number of roots. The mean value of root tensile strength was 31.51 ± 1.05 MPa and root tensile strength decreased with the increase in root diameter, following a power law equation. Using ANCOVA, we found intraspecies variation of tensile strength.

关键词： biomechanical Hornbeam Carpinus betulus root area ratio (RAR) root system root tensile strength.

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Emergy evaluation of the contribution of irrigation water, and its utilization, in three agricultural systems in China

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Frontiers of Earth Science 2014年第3期8卷 325-337页

作者： Dan CHEN Zhaohui LUO Michael WEBBER Jing CHEN Weiguang WANG Key Laboratory of Efficient irrigation-drainage and Agricultural Soil-Water Environment in Southern China (Ministry of Education) College of Water Conservancy and Hvdrooower Engineering Hohai University Nanjing 210098 China department of Resource Management and Geography The University of Melbourne Victoria 3010 Australia College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China

Emergy theory and method are used to evaluate the contribution of irrigation water, and the process of its utilization, in three agricultural systems. The agricultural systems evaluated in this study were rice, wheat, and oilseed rape productions in an irrigation pumping district of China. A corresponding framework for emergy evaluation and sensitivity analysis methods was proposed. Two new indices, the fraction of irrigation water （FIW）, and the irrigation intensity of agriculture （IIA）, were developed to depict the contribution of irrigation water. The calculated FIW indicated that irrigation water used for the rice production system （34.7%） contributed more than irrigation water used for wheat （5.3%） and oilseed rape （11.2%） production systems in a typical dry year. The wheat production with an IIA of 19.0 had the highest net benefit from irrigation compared to the rice （2.9） and oilseed rape （8.9） productions. The transformities of the systems＇ products represented different energy efficiencies for rice （2.50E ＋ 05 sej .J^-1）, wheat （1.66E ＋ 05 sej .J^-1） and oilseed rape （2.14E ＋ 05 sej .J^-1） production systems. According to several emergy indices, of the three systems evaluated, the rice system had the greatest level of sustainability. However, all of them were less sustainable than the ecological agricultural systems. A sensitivity analysis showed that the emergy inputs of irrigation water and nitrogenous fertilizer were the highest sensitivity factors influencing the emergy ratios. Best Management Practices, and other agroecological strategies, could be implemented to make further improvements in the sustainability of the three systems.

关键词： emergy evaluation irrigation agriculture,sustainability

irrigation scheduling for corn in a coastal saline soil

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International Journal of Agricultural and Biological Engineering 2016年第6期9卷 91-99页

作者： Chang Tingting Shao Xiaohou Ye Huan Li Wei Zhang Jie Zhang Zhanyu Key Laboratory of Efficient irrigation-drainage and Agricultural Soil-Water Environment in Southern China of Ministry of Education Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Water Conservancy and Hydropower Investigation and Design Institute of Hebei Tianjin 300250China

Currently,water scarcity is serious and the irrigation scheduling with efficient water use becomes important in *** this study,irrigation systems were scheduled in the saline area along Laizhou *** study was conducted to determine the relation of irrigation regime and crop yield from 2010 to 2012,and the representative rainfall years(high-flow year,normal-flow year and low-flow year)were calculated by analyzing rainfall frequency over 30 *** irrigation regimes were set according to local farmers’*** amounts of T1,T2,T3,T4,T5 and T6 were 225.0 mm,270.0 mm,337.5 mm,300.0 mm,360.0 mm and 450.0 mm,respectively,with the same frequency of four *** results showed that soil salt content decreased with the increase of irrigation water *** corn yield varied from 6560 kg/hm2 to 8060 kg/*** highest yield was obtained from *** functions related to irrigated water(I,mm)for corn yield(Y,kg/hm2)was Y=−0.0397I2+1059.6(R2=0.8892).Aiming at high corn yield,total water supply(irrigation and rainfall)to corn crops was 859 *** amounts at low-flow year(p=80%),normal-flow year(p=50%)and high-flow year(p=20%)were obtained by the simulation of rainfall frequency curve,which were 348 mm,457 mm and 604 mm respectively in the whole growth period(from late June to mid-October).In order to obtain the highest theoretical corn yield,according to field results and rainfall,the optimum irrigation frequency at low-flow year,normal-flow year or high-flow year was four times for corn in the saline area along Laizhou Bay.

关键词： corn(Zea mays) irrigation regime desalination rainfall soil salinity

Effects of irrigation regimes on soil NO_(3)^(-)-N, electrical conductivity and crop yield in plastic greenhouse

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 109-115页

作者： Tingting Chang Yujie Zhang Zhanyu Zhang Xiaohou Shao Weina Wang Jie Zhang Xu Yang Huilian Xu Key Laboratory of Efficient irrigation-drainage and Agricultural Soil-Water Environment in Southern China of Ministry of Education Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China International Nature Farming Research Center Matsumoto390-1401Japan

Developing water-saving irrigation regimes has important practical significance not only in alleviating the crucial water shortage,but also in controlling soil salinization for the protected cultivation in eastern China.A field study with six treatments was conducted to evaluate the effects of different irrigation regimes with subdrainage systems on the soil nitrate nitrogen,salinity and moisture,also evaluate the effects on tomato growth,fruit yield and irrigation water use efficiency(IWUE).The treatments were distinguished by three different irrigation amounts of 310 mm,360 mm and 410 mm,and two irrigation frequencies of 7 and 11 *** showed that the irrigation amount had significant effects on the soil NO_(3)^(-)-N and electric conductivity(EC).A positive correlation was detected between soil NO_(3)^(-)-N(x)and EC(y)at 0-20 m depth after harvest,with a linear equation of y=*** volumetric moisture at 0.10 m and 0.20 m depth was increased as the irrigation amount ***,a higher amount of irrigation increased the fruit yield but reduced the IWUE of *** was also found that smaller irrigation amounts combined with frequent intervals could increase fruit yield and ***,the fruit quality of tomato had a significant(pirrigation ***,the parameters of irrigation regime including the irrigation amount and intervals should be considered comprehensively in order to find a compromise between salinity control and irrigation water use efficiency improvement.

关键词： irrigation regimes greenhouse tomato soil nitrate nitrogen soil electric conductivity soil salinity water use efficiency

Emergy evaluation of a pumping irrigation water production system in China

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Frontiers of Earth Science 2014年第1期8卷 131-141页

作者： Dan CHEN Zhaohui LUO Michael WEBBER Jing CHEN Weiguang WANG Key Laboratory &Efficient irrigation-drainage and Agricultural Soil-Water Environment in Southern China (Ministry of Education) College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China department of Resource Management and Geography The University of Melbourne Victoria 3010 Australia College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China

The emergy concept was used to evaluate a pumping irrigation water production system in China. A framework for emergy evaluation of the significance of irrigation water and its production process was developed. The results show that the irrigation water saved has the highest emergy value （8.73E ＋ 05 sej. J-1）, followed by the irrigation water supplied to farmlands （1.72E ＋ 05 sej.J-1）, the pumped water （4.81E＋04sej.-1）, with the lowest value shown from water taken from the local river （3.72E ＋04sej.j1）. The major contributions to the emergy needed for production are the inputs of soil and water. This production system could contribute to the irrigated agriculture and economy, according to several calculated emergy indices： emergy yield ratio （EYR）, emergy investment ratio （EIR）, environmental load ratio （ELR）, and environmental sustainability index （ESI）. The com- parative analysis shows that the emergy theory and method, different from the conventional monetary-based analysis, could be used to evaluate irrigation water and its production process in terms of the biophysical account. Additional emergy evaluations should be completed on different types of water production and irrigated agricul- tural systems to provide adequate guidelines for the sustainability of irrigation development.

关键词： emergy evaluation irrigation water

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Combining PlanetScope and Sentinel-2 images with environmental data for improved wheat yield estimation

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International Journal of Digital Earth 2023年第1期16卷 847-867页

作者： Nizom Farmonov Khilola Amankulova József Szatmári Jamol Urinov Zafar Narmanov Jakhongir Nosirov LászlóMucsi department of Geoinformatics Physical and Environmental GeographyUniversity of SzegedSzegedHungary Tashkent Institute of irrigation and Agricultural Mechanization Engineers National Research UniversityTashkentUzbekistan department of Land resources Cadastre and GeoinformaticsKarshi Institute of Irrigation and Agrotechnology“TIIAME”National Research UniversityKarshiUzbekistan Soil Science department of the Kashkadarya Region regional division of the Institute of Soil Science and Agrochemical Research KarshiUzbekistan

Satellite images are widely used for crop yield estimation,but their coarse spatial resolution means that they often fail to provide detailed information at thefield ***,a new generation of high-resolution satellites and CubeSat platforms has been *** this study,satellite data sources including PlanetScope and Sentinel-2 were combined with topographic and climatic variables,and the improvement in wheat yield estimation was *** yield data from a combine harvester were used to train and validate a yield estimation model based on random forest *** vegetation indices(NDVI,GNDVI,MSAVI2,MTVI2,MTCI,reNDVI,SAVI,EVI and WDVI)and spectral bands were *** the model training,the Sentinel-2 data realized a slightly higher estimation accuracy than the PlanetScope ***,combining environmental data with the PlanetScope data realized the highest estimation *** the validated models,adding the topographic and climatic datasets to the satellite data sources improved the estimation accuracy,and the results were slightly better with the Sentinel-2 data than with the PlanetScope *** data of the milk and dough stages provided the highest estimation accuracy of the wheat yield at 210–225 days after sowing.

关键词： Remote sensing BBCH-scale MSAVI2 PlanetScope random forest

Monitoring and analysing the Emirate of Dubai’s land use/land cover changes:an integrated,low-cost remote sensing approach

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International Journal of Digital Earth 2018年第11期11卷 1132-1150页

作者： Samy Ismail Elmahdy Mohamed Mostafa Mohameda Civil and Environmental Engineering department College of Engineering United Arab Emirates UniversityAl-AinUnited Arab Emirates irrigation and Hydraulics department Faculty of EngineeringCairo UniversityGizaEgypt

This study presents a modified low-cost approach,which integrates the spectral angle mapper and image difference algorithms in order to enhance classification maps for the purpose of monitoring and analysing land use/land cover change between 2000 and 2015 for the Emirate of *** approach was modified by collecting 320 training samples from QuickBird images with a spatial resolution of 0.6 m,as well as carrying out field observations,followed by the application of a 3×3 Soble filter,sieving classes,majority/minority analysis,and clump classes of the obtained classification *** accuracy assessment showed that the targeted 2000,2005,2010 and 2015 classification maps have 88.1252%,89.0699%,90.1225%and 96.0965%accuracy,*** results showed that the built-up area increased by 233.721 km^(2)(5.81%)between 2000 and 2005 and continues to increase even up and till the present *** assessment of changes in the periods 2000–2005 and 2010–2015 confirmed that net vegetation area losses were more pronounced from 2000 to 2005 than from 2010 to 2015,dropping from 47,618 to 40,820 km^(2),*** study is aimed to assist urban planners and decision-makers,as well as research institutes.

关键词： Dubai change detection image difference SAM algorithm

Evaluation of suspended load transport rate using transport formulas and arti- ficial neural network models (Case study: Chelchay Catchment)

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Journal of Hydrodynamics 2013年第3期25卷 459-470页

作者： HADDADCHI Arman MOVAHEDI Neshat VAHIDI Elham OMID Mohammad Hossein DEHGHANI Amir Ahmad Australian Rivers Institute Griffith University Nathan QLD 4111 Australia department of Water Engineering Gorgan University of Agricultural Sciences and Natural Resources GorganIran department of irrigation and Reclamation Engineering University of Tehran Karaj Iran

Accurate estimation of sediment load or transport rate is very important to a wide range of water resources projects. This study was undertaken to determine the most appropriate model to predict suspended load in the Chelehay Watershed, northeast of Iran. In total, 59 data series were collected from four gravel bed-rivers and a sand bed river and two depth integrating suspended load samplers to evaluate nine suspended load formulas and feed forward backpropagation Artificial Neural Network （ANN） structures. Although the Chang formula with higher correlation coefficient （r = 0.69） and lower Root Mean Square Error （RMSE = 0.013） is the best suspended load predictor among the nine studied formulas, the ANN models significantly outperform traditional suspended load formulas and show their superior performance for all statistical parameters. Among different ANN structures two models inclu- ding 4 inputs, 4 hidden and one output neurons, and 4 inputs, 4 and one hidden and one output neurons provide the best simulation with the RMSE values of 0.0009 and 0.001, respectively.

关键词： sediment transport suspended load formulas Artificial Neural Network (ANN) river engineering

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