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A STUDY ON THE BALANCE OF WATER AND SOIL RESOURCES IN THE HEXI CORRIDOR,GANSU PROVINCE
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作者 Chen Changyu Applied Climatical Institute, Gansu Meteorological Bureau 《干旱区资源与环境》 CSCD 1993年第Z1期148-150,共3页
1. Actual water resources In the Hexi Corridor, annual precipitation is only 35-200mm, showing semi-desertand desert landscape. But in the Qilian Mountains which are in the south of the Hexi Corri-dor, there is more p... 1. Actual water resources In the Hexi Corridor, annual precipitation is only 35-200mm, showing semi-desertand desert landscape. But in the Qilian Mountains which are in the south of the Hexi Corri-dor, there is more precipitation. In the Shiyanghe, Heihe, Shulehe River basins average an-nual precipitation is respectively 2.3, 2.7, 3.6 times larger than that of the Hexi 展开更多
关键词 Hexi CORRIDOR water and soil resources OASIS
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The Impact of Soil Freezing/Thawing Processes on Water and Energy Balances 被引量:5
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作者 张霞 孙菽芬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第1期169-177,共9页
A frozen soil parameterization coupling of thermal and hydrological processes is used to investigate how frozen soil processes affect water and energy balances in seasonal frozen soil. Simulation results of soil liqui... A frozen soil parameterization coupling of thermal and hydrological processes is used to investigate how frozen soil processes affect water and energy balances in seasonal frozen soil. Simulation results of soil liquid water content and temperature using soil model with and without the inclusion of freezing and thawing processes are evaluated against observations at the Rosemount field station. By comparing the simulated water and heat fluxes of the two cases, the role of phase change processes in the water and energy balances is analyzed. Soil freezing induces upward water flow towards the freezing front and increases soil water content in the upper soil layer. In particular, soil ice obviously prevents and delays the infiltration during rain at Rosemount. In addition, soil freezingthawing processes alter the partitioning of surface energy fluxes and lead the soil to release more sensible heat into the atmosphere during freezing periods. 展开更多
关键词 frozen soil water and energy balances freezing/thawing processes surface flux
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THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR 被引量:9
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作者 GAOQian-zhao DUHu-lin 《Chinese Geographical Science》 SCIE CSCD 2002年第1期23-29,共7页
The Hexi Corridor is an important base of agriculture development inNorthwest China. According to recent statistics, there are 65. 94 x 10~8m^3 of water resourcesavailable in the Hexi Corridor. At present, net consump... The Hexi Corridor is an important base of agriculture development inNorthwest China. According to recent statistics, there are 65. 94 x 10~8m^3 of water resourcesavailable in the Hexi Corridor. At present, net consumption in development and utilization is 43. 33x 10~8m^3. Water supply and demand reach a balance on the recent level of production, but loss ofevaporation and evapotranspiration is as much as 25. 69 x 1010~8m^3. So net use efficiency of waterresources is 59% Based on analyzing balance between water and land considering ecologicalenvironment at present, there exists the serious water shortage in the Shiyang River system whereirrigation lands have overloaded. There is a comparative balance between supply and demand of waterresource in the Heihe River system; and the Sule River system has some surplus water to extendirrigation land. Use of agriculture water accounts for 83. 3% and ecological forest and grass for 6.9% . The Hexi Corridor still has a great potential for water saving in agriculture production.Water-saving efficiency of irrigation is about 10% by using such traditional technologies as furrowand border-dike irrigation and small check irrigation, and water-saving with plastic film cover andtechniques of advanced sprinkler and drip/micro irrigation etc. can save more than 60% of irrigatedwater. Incremental irrigation area for water-saving potential in the Hexi Corridor has beenestimated as 56% - 197% to original irrigation area. So the second water sources can be developedfrom water saving agriculture in the Hexi Corridor under Development of the Western Part of China inlarge scale. This potential can be realized step by step through developing the water-savingmeasures, improving the ecological condition of oasis agriculture, and optimizing allocation ofwater resources in three river systems. 展开更多
关键词 water resources balance between supply and demand water-saving potential ofagriculture hexi corridor
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Assessment and utilization of soil water resources 被引量:1
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作者 WANG Hui-xiao, LIU Chang-ming, YANG Zhi-feng (State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第1期87-91,共5页
Based on the analyses of water interactions and water balance, this paper discusses the issues on the assessment and regulation of soil water resources, which lays the scientific basis for limited irrigation and water... Based on the analyses of water interactions and water balance, this paper discusses the issues on the assessment and regulation of soil water resources, which lays the scientific basis for limited irrigation and water-saving agriculture. 展开更多
关键词 soil water resources ASSESSMENT water interactions water balance
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Analysis of Soil and Water Balance on the Land Arrangement Function
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作者 Tashpolat Tiyip 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第2期88-92,共5页
The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supp... The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to im- prove land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project. 展开更多
关键词 soil and water balance Land arrangement Fuhai COUNTY
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The evolution and enlightenment of water resourcesaccounting from accounts to balance sheet
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作者 FuHui Jian XiaoYu Song +1 位作者 LiLi Li WenQi Gao 《Research in Cold and Arid Regions》 CSCD 2016年第2期156-162,共7页
The Third Plenary Session of the 18 th Central Committee of the Communist Party of China has proposed an important national strategic decision: to explore and establish the balance sheet of natural resources, to imple... The Third Plenary Session of the 18 th Central Committee of the Communist Party of China has proposed an important national strategic decision: to explore and establish the balance sheet of natural resources, to implement leaders’ of-office auditing system about natural resources assets. Water is one of the most essential nature resources of human beings; water resources accounting, as an important water resources management tool, is an essential part of compiling the natural resources balance sheet. In this paper, we provide a summary of the historic evolution of water resources accounting and analyze its application in some typical countries. Although water resources accounting and water resources balance sheet reflect different implications and focus, both require water resources accounts as the basis in system establishment. 展开更多
关键词 water resources water accounts water accounting water balance sheet
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Antecedent Precipitation Index to Estimate Soil Moisture and Correlate as a Triggering Process in the Occurrence of Landslides
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作者 Marcio Augusto Ernesto De Moraes Walter Manoel Mendes Filho +6 位作者 Rodolfo Moreda Mendes Cassiano Antonio Bortolozo Daniel Metodiev Marcio Roberto Magalhães De Andrade Harideva Marturano Egas Tatiana Sussel Gonçalves Mendes Luana Albertani Pampuch 《International Journal of Geosciences》 CAS 2024年第1期70-86,共17页
Landslides are highly dangerous phenomena that occur in different parts of the world and pose significant threats to human populations. Intense rainfall events are the main triggering process for landslides in urbaniz... Landslides are highly dangerous phenomena that occur in different parts of the world and pose significant threats to human populations. Intense rainfall events are the main triggering process for landslides in urbanized slope regions, especially those considered high-risk areas. Various other factors contribute to the process;thus, it is essential to analyze the causes of such incidents in all possible ways. Soil moisture plays a critical role in the Earth’s surface-atmosphere interaction systems;hence, measurements and their estimations are crucial for understanding all processes involved in the water balance, especially those related to landslides. Soil moisture can be estimated from in-situ measurements using different sensors and techniques, satellite remote sensing, hydrological modeling, and indicators to index moisture conditions. Antecedent soil moisture can significantly impact runoff for the same rainfall event in a watershed. The Antecedent Precipitation Index (API) or “retained rainfall,” along with the antecedent moisture condition from the Natural Resources Conservation Service, is generally applied to estimate runoff in watersheds where data is limited or unavailable. This work aims to explore API in estimating soil moisture and establish thresholds based on landslide occurrences. The estimated soil moisture will be compared and calibrated using measurements obtained through multisensor capacitance probes installed in a high-risk area located in the mountainous region of Campos do Jordão municipality, São Paulo, Brazil. The API used in the calculation has been modified, where the recession coefficient depends on air temperature variability as well as the climatological mean temperature, which can be considered as losses in the water balance due to evapotranspiration. Once the API is calibrated, it will be used to extrapolate to the entire watershed and consequently estimate soil moisture. By utilizing recorded mass movements and comparing them with API and soil moisture, it will be possible to determine thresholds, thus enabling anticipation of landslide occurrences. 展开更多
关键词 LandSLIDES Antecedent Precipitation Index soil Moisture Threshold water balance
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Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China 被引量:11
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作者 JI Xi-bin KANG Er-si +3 位作者 CHEN Ren-sheng ZHAO Wen-zhi XlAO Sheng-chun JIN Bo-wen 《Agricultural Sciences in China》 CAS CSCD 2006年第2期130-140,共11页
Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance o... Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year (2003), the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system. 展开更多
关键词 middle reaches of Heihe River irrigation region water resources supply and demand balance evaluation of the security of water resources
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Soil water resources use limit in the loess plateau of China 被引量:4
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作者 Ting Ning Zhongsheng Guo +1 位作者 Mancai Guo Bing Han 《Agricultural Sciences》 2013年第5期100-105,共6页
Soil water is a key factor limiting plant growth in water-limited regions. Without limit of soil water used by plants, soil degradation in the form of soil desiccation is easy to take place in the perennial forestland... Soil water is a key factor limiting plant growth in water-limited regions. Without limit of soil water used by plants, soil degradation in the form of soil desiccation is easy to take place in the perennial forestland and grassland with too higher density or productivity. Soil water resources use limit (SWRUL) is the lowest control limit of soil water resources which is used by plants in those regions. It can be defined as soil water storage within the maximum infiltration depth in which all of soil layers belong to dried soil layers. In this paper, after detailed discussion of characteristics of water resources and the relationship between soil water and plant growth in the Loess Plateau, the definition, quantitative method, and practical applications of SWRUL are introduced. Henceforth, we should strengthen the study of SWRUL and have a better understanding of soil water resources. All those are of great importance for designing effective restoration project and sustainable management of soil water resources in water- limited regions in the future. 展开更多
关键词 Infiltration Depth Dried soil Layer WILTING Coefficient soil water resources USE LIMIT Initial Stage to Regulate the Relationship between soil water and Plant Growth
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Soil and Water Resources and Land Sustainable Productivity in the Catchment Area with Intensive Management in Hilly Red Soil Regions,China
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作者 HUANGDao-you WANGKe-lin +2 位作者 CHENGui-qiu HUANGMin PENGTing-bo 《Agricultural Sciences in China》 CAS CSCD 2004年第5期356-363,共8页
Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studie... Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly. 展开更多
关键词 Catchment area with intensive management soil and water resources soil fertility Land sustainable productivity Hilly red soil region
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Application Research of Water Resources Balance Sheet in Public Project Governance 被引量:1
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作者 LIU Fang MIAO Wang 《通讯和计算机(中英文版)》 2017年第3期115-121,共7页
关键词 水资源短缺 工程治理 公共项 平衡表 应用 生态文明建设 水生态环境保护 水资源承载能力
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Biocrust-induced partitioning of soil water between grass and shrub in a desert steppe of Northwest China
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作者 YANG Xinguo WANG Entian +1 位作者 QU Wenjie WANG Lei 《Journal of Arid Land》 SCIE CSCD 2023年第1期63-76,共14页
Maintaining the stability of exotic sand-binding shrub has become a large challenge in arid and semi-arid grassland ecosystems in northern China.We investigated two kinds of shrublands with different BSCs(biological s... Maintaining the stability of exotic sand-binding shrub has become a large challenge in arid and semi-arid grassland ecosystems in northern China.We investigated two kinds of shrublands with different BSCs(biological soil crusts)cover in desert steppe in Northwest China to characterize the water sources of shrub(Caragana intermedia Kuang et H.C.Fu)and grass(Artemisia scoparia Waldst.et Kit.)by stable 18O isotopic.Our results showed that both shrublands were subject to persistent soil water deficiency from 2012 to 2017,the minimum soil depth with CV(coefficient of variation)<15% and SWC(soil water content)<6% was 1.4 m in shrubland with open areas lacking obvious BSC cover,and 0.8 m in shrubland covered by mature BSCs.For C.intermedia,a considerable proportion of water sources pointed to the surface soil.Water from BSCs contributed to averages 22.9%and 17.6%of the total for C.intermedia and A.scoparia,respectively.C.intermedia might use more water from BSCs in rainy season than dry season,in contrast to A.scoparia.The relationship between shrub(or grass)and soil water by δ^(18)O shown significant differences in months,which partly verified the potential trends and relations covered by the high variability of the water source at seasonal scale.More fine roots at 0-5 cm soil layer could be found in the surface soil layer covered by BSCs(8000 cm/m^(3))than without BSCs(3200 cm/m^(3)),which ensured the possibility of using the surface soil water by C.intermedia.The result implies that even under serious soil water deficiency,C.intermedia can use the surface soil water,leading to the coexistence between C.intermedia and A.scoparia.Different with the result from BSCs in desert areas,the natural withdrawal of artificial C.intermedia from desert steppe will be a long-term process,and the highly competitive relationship between shrubs and grasses also determines that its habitat will be maintained in serious drought state for a long time. 展开更多
关键词 desert steppe biological soil crusts water resource Caragana intermedia Artemisia scoparia
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SimET: An open-source tool for estimating crop evapotranspiration and soil water balance for plants with multiple growth cycles
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作者 Minguo Liu Mei Yang Huimin Yang 《The Crop Journal》 SCIE CSCD 2023年第5期1579-1585,共7页
Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many de... Accurate estimation of crop evapotranspiration(ETc) and soil water balance, which is vital for optimizing water management strategy in crop production, can be performed by simulation. But existing software has many deficiencies, including complex operation, limited scalability, lack of batch processing, and a single ETc model. Here we present simET, an open-source software package written in the R programming language. Many concepts involved in crop ETc simulation are condensed into functions in the package. It includes three widely used crop ETc models built on these functions: the single-crop coefficient,double-crop coefficient, and Shuttleworth–Wallace models, along with tools for preparing model data and comparing estimates. SimET supports ETc simulation in crops with repeated growth cycles such as alfalfa, a perennial forage crop that is cut multiple times annually. 展开更多
关键词 Crop evapotranspiration soil water balance Evapotranspiration model R package
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Field Assessment of Soil Water Storage and Actual Evapotranspiration of Rainfed Maize (<i>Zea mays</i>L.) Genotypes in a Coastal Savannah Environment
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作者 Justice Okona Frimpong Marcus Quaynor Addy +5 位作者 Emmanuel Ofori Ayeh Harry Mensah Amoatey Jacob Teye Kutufam Bertrand Quaye Joshua Osei Sintim Daniel Kwasi Asare 《Open Journal of Soil Science》 2012年第3期213-222,共10页
A field experiment was carried out in a coastal savannah agro-ecological zone of Ghana to assess the dynamics of stored soil water and actual evapotranspiration (AET) of three maize genotypes (Obatanpa, Mamaba, and Go... A field experiment was carried out in a coastal savannah agro-ecological zone of Ghana to assess the dynamics of stored soil water and actual evapotranspiration (AET) of three maize genotypes (Obatanpa, Mamaba, and Golden Crystal) grown under rainfed conditions. Access tubes were installed to a depth of 120 cm for soil water content monitoring using a neutron probe meter. The soil water balance model of plant root zone was used to estimate AET at different crop growth stages. On average, the rate of AET for Obatanpa, Mamaba, and Golden Crystal maize genotypes were estimated as 4.32, 4.46, and 3.72 mm·day–1, respectively, for the major cropping season as against corresponding values of 3.88, 4.00 and 3.72 mm day–1 for the minor cropping season. Mamaba had higher values of AET from 42 DAE (days after emergence) to 84 DAE during the minor cropping season while it had low AET values during the major cropping season. The positive balance in stored soil water in the root zone of Obatanpa was the highest from 42 DAE to 84 DAE followed by Mamaba and Golden Crystal during the major cropping season. Mamaba, on the other hand, had the highest AET from 70 DAE to 84 DAE. Obatanpa used 55.6% of stored soil water for AET, which was the highest among the maize genotypes during the major cropping season. Golden Crystal and Mamaba followed with 53.3% and 51.5%. For the minor cropping season, 48.5% of stored soil water was used by Mamaba for AET, followed by Obatanpa, (46.4%) and Golden Crystal (43.2%). A strong positive significant (p ≤ 0.05) linear correlation existed between AET and precipitation with the coefficient of determination (R2) being 69.2 for Obatanpa, 88.5 for Mamaba and 82.8 for Golden Crystal for the major cropping season. Higher R2 values (98.0, for Obatanpa, 94.1 for Mamaba and 98.9 for Golden Crystal) were, however, obtained for the minor cropping season. Additionally, a strong linear relationship was found between AET and precipitation, suggesting the need to formulate strategies for enhancing effective use of precipitation in sustained rainfed maize production. 展开更多
关键词 soil water balance Actual Evapotranspiration Stored soil water RAINFED MAIZE Production
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Roles of Science and Technology in Soil and Water Conservation in the New Era
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作者 Feng Xingping Jiang Tao 《Meteorological and Environmental Research》 CAS 2018年第6期5-14,20,共11页
Firstly,current situation and main problems of science and technology development of soil and water conservation were analyzed,and then roles of science and technology in soil and water conservation were studied. At l... Firstly,current situation and main problems of science and technology development of soil and water conservation were analyzed,and then roles of science and technology in soil and water conservation were studied. At last,exploration ways of roles of science and technology in soil and water conservation were proposed. 展开更多
关键词 soil and water conservation Science and technology development water and land resources Ecological environment
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Spatial Availability of Nitrogen and Pesticides in the Surface Layers of Agricultural Soils of Tropical Hydrosystems in the Wet Season: Case of the BéréWatershed in Côte d’Ivoire (West Africa)
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作者 Mian Germain Eba Kouakou Sylvain Akpo +2 位作者 Pétémanangnan Jean-Marie Ouattara Tiangoua Koné Lacina Coulibaly 《Journal of Agricultural Chemistry and Environment》 2021年第2期143-168,共26页
The objective of this study was to assess the contribution of the spatial organization of cropping systems and the physicochemical properties of surface layers of the agricultural zones soils in tropical hydrosystems ... The objective of this study was to assess the contribution of the spatial organization of cropping systems and the physicochemical properties of surface layers of the agricultural zones soils in tropical hydrosystems to the spatial availability of nitrogen and pesticides during the wet season, such as the Béré watershed (BW) in C<span style="white-space:nowrap;">?</span>te d’Ivoire. For this purpose, after mapping the spatial distribution of the BW cropping systems based on the likelihood classification methodology of satellite images of the study area, 27 samples from the 0 - 20 cm horizon of the soil surface layers of the agricultural areas were taken during the wet and agricultural season of the year 2016. The Kjeldahl method has been used to evaluate the total nitrogen concentration and high-performance liquid chromatography (HPLC) chain made it possible for the analysis of pesticide residues in the soil solutions. Geostatistical analysis and processing of spatial data and physicochemical and agrochemical soil parameters revealed that two major agricultural areas stand out in the BW, namely the Béré upstream watershed (BUW) dominated at 32.65% by annual croppings (maize, cotton, rainfed or lowland rice, market gardening, etc.) and the Béré downstream watershed (BDW) by large areas of perennial croppings (cashew nuts, cocoa, etc.), <em>i.e.</em> 21.47%. Agricultural soils in BW are usually of the moderately desaturated ferralitic type with a low acid pH and a quite strong temperature, such as those of tropical soils’ characteristics. However, agricultural soils in the BUW are characterized by higher proportions of sand and coarse sand. The parameters such as total porosity, cation exchange capacity, clay, organic matter, silt, fine silt, coarse silt, and potassium ions, are higher in the soils of the agricultural area of the BDW. Moreover, soils in the agricultural areas of the BUW are less rich in total nitrogen (0.84 g<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>) in contrast to those of the BDW (1.2 g<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>). On the other hand, the median concentrations of total pesticides remain very high in the BUW (193.80 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>) in front of those of the BDW (94.81 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>). In addition, the biological family of herbicides was the most notable in BW. The chemical families of triazines (100% detection;79.37 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>) are the most important in the agricultural area of the BUW with the very significant presence of active molecules of pesticides such as simazine (92.86% detection;13.17 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>). However, in the BDW, urea substitute (100% detection;44.02 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>) dominate, including the active substance chlortoluron (84.62% detection;10.12 μg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>). The presence and abundance of nitrogen and pesticides in the soils of the agricultural areas of BW are strongly linked to the intensive use of these agrochemicals in cropping systems in recent decades in West African countries, even though most of the active molecules found are forbidden in several countries, especially in European countries. These are applied to tropical agricultural soils with physicochemical characteristics favorable to their retention in wet weather, as confirmed by the case of BW’s agricultural soils. Therefore, the BW’s water resources present worrying risks of contamination during rainy events that deserve to be assessed and monitored. Hence the need to take mitigating measures to this effect in order to preserve the quality of the environment. 展开更多
关键词 Agrochimical Products soils Contamination water resources Pollution West Africa Tropical Hydrosystems Béré watershed Côte d’Ivoire
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Effects of saline irrigation on soil salt accumulation and grain yield in the winter wheat-summer maize double cropping system in the low plain of North China 被引量:14
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作者 LIU Xiu-wei Til Feike +3 位作者 CHEN Su-ying SHAO Li-wei SUN Hong-yong ZHANG Xi-ying 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第12期2886-2898,共13页
In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to ... In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to realize high crop productivity. Using the vast water resources of the saline upper aquifer for irrigation during WW jointing stage, may help to bridge the peak of dry season and relieve the tight water situation in the region. A field experiment was conducted during 2009-2012 to investigate the effects of saline irrigation during WW jointing stage on soil salt accumulation and productivity of WW and SM. The experiment treatments comprised no irrigation (T1), fresh water irrigation (T2), slightly saline water irrigation (T3:2.8 dS m-l), and strongly saline water irrigation (T4:8.2 dS m-1) at WW jointing stage. With regard to WW yields and aggregated annual WW-SM yields, clear benefits of saline water irrigation (T3 & T4) compared to no irrigation (T1), as well as insignificant yield losses compared to fresh water irrigation (T2) occurred in all three experiment years. However, the increased soil salinity in eady SM season in consequence of saline irrigation exerted a negative effect on SM photosynthesis and final yield in two of three experiment years. To avoid the negative aftereffects of saline irrigation, sufficient fresh water irrigation during SM sowing phase (i.e., increase from 60 to 90 mm) is recommended to guarantee good growth conditions during the sensitive early growing period of SM. The risk of long-term accumulation of salts as a result of saline irrigation during the peak of dry season is considered low, due to deep leaching of salts during regularly occurring wet years, as demonstrated in the 2012 experiment year. Thus, applying saline water irrigation at jointing stage of WW and fresh water at sowing of SM is most promising to realize high yield and fresh irrigation water saving. 展开更多
关键词 winter wheat summer maize soil salinity saline water irrigation salt balance
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Calculation and Simulation of Evapotranspiration of Applied Water 被引量:8
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作者 Richard L Snyder Shu Geng +1 位作者 Morteza Orang Sara Sarreshteh 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第3期489-501,共13页
The University of California, Davis and the California Department of Water Resources have developed a weather generator application program “SIMETAW” to simulate weather data from climatic records and to estimate re... The University of California, Davis and the California Department of Water Resources have developed a weather generator application program “SIMETAW” to simulate weather data from climatic records and to estimate reference evapotranspiration (ETo) and crop evapotranspiration (ETc) with the generated simulation data or with observed data. A database of default soil depth and water holding characteristics, effective crop rooting depths, and crop coefficient (Kc) values to convert ETo to ETc are input into the program. After calculating daily ETc, the input and derived data are used to determine effective rainfall and to generate hypothetical irrigation schedules to estimate the seasonal and annual evapotranspiration of applied water (ETaw), where ETaw is the net amount of irrigation water needed to produce a crop. in this paper, we will discuss the simulation model and how it determines ETaw for use in water resources planning. 展开更多
关键词 weather generator water balance crop water requirements water resource planning crop coefficient
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California Simulation of Evapotranspiration of Applied Water and Agricultural Energy Use in California 被引量:4
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作者 Morteza N Orang Richard L Snyder +6 位作者 Shu Geng Quinn J Hart Sara Sarreshteh Matthias Falk Dylan Beaudette Scott Hayes Simon Eching 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1371-1388,共18页
The California Simulation of Evapotranspiration of Applied Water (CaI-SIMETAW) model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily s... The California Simulation of Evapotranspiration of Applied Water (CaI-SIMETAW) model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily soil water balance and determine crop evapotranspiration (ETo), evapotranspiration of applied water (ETaw), and applied water (AW) for use in California water resources planning. ETaw is a seasonal estimate of the water needed to irrigate a crop assuming 100% irrigation efficiency. The model accounts for soils, crop coefficients, rooting depths, seepage, etc. that influence crop water balance. It provides spatial soil and climate information and it uses historical crop and land-use category information to provide seasonal water balance estimates by combinations of detailed analysis unit and county (DAU/County) over Califomia. The result is a large data base of ETc and ETaw that will be used to update information in the new California Water Plan (CWP). The application uses the daily climate data, i.e., maximum (Tx) and minimum (Tn) temperature and precipitation (Pcp), which were derived from monthly USDA-NRCS PRISM data (PRISM Group 2011) and daily US National Climate Data Center (NCDC) climate station data to cover California on a 4 kmx4 km change grid spacing. The application uses daily weather data to determine reference evapotranspiration (ETo), using the Hargreaves-Samani (HS) equation (Hargreaves and Samani 1982, 1985). Because the HS equation is based on temperature only, ETo from the HS equation were compared with CIMIS ETo at the same locations using available CIMIS data to determine correction factors to estimate CIMIS ETo from the HS ETo to account for spatial climate differences. CaI-SIMETAW also employs near real-time reference evapotranspiration (ETo) information from Spatial CIMIS, which is a model that combines weather station data and remote sensing to provide a grid of ETo information. A second database containing the available soil water holding capacity and soil depth information for all of California was also developed from the USDA-NRCS SSURGO database. The Cal-SIMETAW program also has the ability to generate daily weather data from monthly mean values for use in studying climate change scenarios and their possible impacts on water demand in the state. The key objective of this project is to improve the accuracy of water use estimates for the California Water Plan (CWP), which provides a comprehensive report on water supply, demand, and management in California. In this paper, we will discuss the model and how it determines ETaw for use in water resources planning. 展开更多
关键词 soil water balance crop water requirements weather generator water resource planning crop coefficient energy use
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Impact of Land Use Change on Groundwater Recharge in Guishui River Basin,China 被引量:5
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作者 PAN Yun GONG Huili +2 位作者 ZHOU Demin LI Xiaojuan NAKAGOSHI Nobukazu 《Chinese Geographical Science》 SCIE CSCD 2011年第6期734-743,共10页
It is important to understand how land use change impacts groundwater recharge, especially for regions that are undergoing rapid urbanization and there is limited surface water. In this study, the hydrological process... It is important to understand how land use change impacts groundwater recharge, especially for regions that are undergoing rapid urbanization and there is limited surface water. In this study, the hydrological processes and re- charge ability of various land use types in Guishui River Basin, China (in Beijing Municipality) were analyzed. The impact of land use change was investigated based on water balance modeling, WetSpass and GIS. The results indicate that groundwater recharge accounts for only 21.16% of the precipitation, while 72.54% is lost in the form of evapotranspiration. The annual-lumped groundwater recharge rate decreases in the order of cropland, grassland, urban land, and forest. Land use change has resulted in a decrease of 4 x 106 m3 of yearly groundwater recharge in the study area, with a spatially averaged rate of 100.48 mm/yr and 98.41 mm/yr in 1980 and 2005, respectively. This variation has primarily come from an increase of urban area and rural settlements, as well as a decrease of cropland. 展开更多
关键词 groundwater recharge land use change soil water balance hydrological processes
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