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新安江模型(三水源)分水源参数区域规律研究 被引量:6
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作者 陈志明 《河海大学学报(自然科学版)》 CAS CSCD 1990年第6期133-138,共6页
1 前言新安江模型(三水源)概念清楚,结构简单,参数有明确的物理意义,是取决于气候及下垫面条件.直接根据流域下垫面条件确定一些模型参数一直是努力的目标之一,关于这方面已有一些研究,如 WM,UM,LM,B,C 地区上数值分布的大概范围等.但... 1 前言新安江模型(三水源)概念清楚,结构简单,参数有明确的物理意义,是取决于气候及下垫面条件.直接根据流域下垫面条件确定一些模型参数一直是努力的目标之一,关于这方面已有一些研究,如 WM,UM,LM,B,C 地区上数值分布的大概范围等.但对日模型而言很重要的分水源参数 SM,KI,KG 与流域下垫面条件的关系研究得还较少.文献[2]得出植被率越高,酸性花岗岩面积占的比重越大,分水源参数 SM 越大的结论,据笔者分析,在影响分水源参数 SM,KI,KG 的下垫面因素中,地质条件往往是主要方面.地质条件对参数的影响往往表现在岩性对参数的影响上,一个流域往往由多种岩性的岩石组成。 展开更多
关键词 分水源 模型参数 计算
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一种利用流量过程线估算新安江模型分水源参数的方法 被引量:3
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作者 童冰星 姚成 黄小祥 《中国农村水利水电》 北大核心 2017年第11期26-30,共5页
新安江模型分水源计算时较多的待定参数往往会导致"异参同效"现象的发生,这样不仅使得率定出的参数可能不准确,而且给模型的使用带来不便。将流域出口的流量过程线进行径流分割,计算得到壤中水径流深。同时将壤中水径流深与... 新安江模型分水源计算时较多的待定参数往往会导致"异参同效"现象的发生,这样不仅使得率定出的参数可能不准确,而且给模型的使用带来不便。将流域出口的流量过程线进行径流分割,计算得到壤中水径流深。同时将壤中水径流深与分水源参数建立函数关系,从而利用流量过程线估算新安江模型分水源参数。以陕西省陈河流域为例,将估算出的分水源参数应用于新安江模型进行洪水模拟,并取得了良好的模拟结果。与传统的参数率定方法相比,本方法能够快速且较为准确地估算出新安江模型的分水源参数,减少了待率定的参数的个数,在一定程度上降低了异参同效对模型应用的影响。 展开更多
关键词 分水源参数 异参同效 流量过程线 新安江模型
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我国水资源承载力分析及分区管控对策 被引量:9
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作者 马睿 李云玲 +1 位作者 何君 张小丽 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2023年第2期209-217,共9页
从地表水、地下水和用水总量3个方面对我国水资源承载状况(不超载、临界超载和超载)进行评价,以地表水、地下水和用水总量承载状况的最差评价结果作为综合评价结果。在此基础上分析城市群、经济区、能源基地和粮食主产区的水资源承载力... 从地表水、地下水和用水总量3个方面对我国水资源承载状况(不超载、临界超载和超载)进行评价,以地表水、地下水和用水总量承载状况的最差评价结果作为综合评价结果。在此基础上分析城市群、经济区、能源基地和粮食主产区的水资源承载力,最终提出分区管控对策。结果表明:水资源超载区和临界超载区涉及全国53%的国土面积、近60%的人口和GDP,水资源量仅占全国的28%;地表水超载与临界超载单元有151个,主要分布在海河、辽河、黄河中下游支流、淮河中游水系、西北内陆河局部河段;地下水超载与临界单元有107个,超采的地下水主要用于农业灌溉和城市发展。重要城市群、经济区、能源基地几乎全部分布在水资源超载或临界超载地区,17个粮食主产区中有14个在水资源超载和临界超载地区。基于水资源承载能力分析结果,提出超载区“补水”,临界区“控水”,不超载区“保水”的分区管控对策。 展开更多
关键词 水资源承载力 分水源 重点区域 区管控 对策
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基于水源水质分期的水处理工艺模糊优化组合(英文) 被引量:1
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作者 李玉仙 黄廷林 何文杰 《西安建筑科技大学学报(自然科学版)》 CSCD 北大核心 2007年第2期199-205,共7页
工艺选优的基本原则是在原水水质不断变化的情况下,选取满足出水水质约束的最经济最合理的工艺方案.本文将模糊优化理论应用到给水处理工艺的模糊选优上,对所选用的4个目标设定不同的权重,在T水源的不同水质期内对中试实际运行工艺模糊... 工艺选优的基本原则是在原水水质不断变化的情况下,选取满足出水水质约束的最经济最合理的工艺方案.本文将模糊优化理论应用到给水处理工艺的模糊选优上,对所选用的4个目标设定不同的权重,在T水源的不同水质期内对中试实际运行工艺模糊选优.结果表明在5月-9月期间内水源水质对水处理工艺要求较为严格,其对应的最不利水质条件下的最复杂工艺为“O3预氧化-混凝-气浮-过滤-O3-生物活性炭”.其他水质期内原水水质较好,可以对该工艺方案进行组合,超越部分处理单元. 展开更多
关键词 水源水质 工艺优化组合 模糊优化 Kmeans聚类 主成
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基于多水源分质供水技术的砣矶岛水资源优化配置
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作者 李东洋 田林 +2 位作者 刘玮 王锐浩 王晓丽 《海洋开发与管理》 2018年第4期101-105,共5页
水资源紧缺问题制约砣矶岛社会经济发展。文章对砣矶岛水资源现状进行实地调研,主要包括地表水、地下水和海水淡化水的水量和水质;根据相关资料和发展规划,对砣矶岛水资源供需情况进行预测,得出2020年需水总量为48.33万m3,水资源缺口最... 水资源紧缺问题制约砣矶岛社会经济发展。文章对砣矶岛水资源现状进行实地调研,主要包括地表水、地下水和海水淡化水的水量和水质;根据相关资料和发展规划,对砣矶岛水资源供需情况进行预测,得出2020年需水总量为48.33万m3,水资源缺口最高可达9.19万m3;通过总结目前岛上供水存在的问题,提出多水源分质供水的水资源优化配置方案,即增加9.19万m3/a的海水淡化工程以及污水处理和中水回用装置,生活用水采用地下水与淡化水的混合水,生产用水采用淡化水,生态用水采用地表水和回用水,同时建设水资源监视监测系统,提高水资源综合利用率。 展开更多
关键词 水源质供水 水资源 海岛管理 海水淡化 供需预测
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浙江省区域水资源承载力分析及强载措施研究 被引量:7
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作者 周芬 魏婧 +1 位作者 王贝 王丽婷 《水利规划与设计》 2020年第8期39-43,67,共6页
浙江省水资源量总体丰富,但水资源禀赋和人口产业集聚倒挂情况十分突出。水资源承载力研究表明,位于杭州湾南北两岸的杭嘉湖区和萧绍宁舟区水库城镇供水能力承载力不足。文章针对浙江省水资源承载力存在的空间分布不均问题,建议从"... 浙江省水资源量总体丰富,但水资源禀赋和人口产业集聚倒挂情况十分突出。水资源承载力研究表明,位于杭州湾南北两岸的杭嘉湖区和萧绍宁舟区水库城镇供水能力承载力不足。文章针对浙江省水资源承载力存在的空间分布不均问题,建议从"控需"和"优配"两个途径增强水资源承载力,促进水资源与区域经济要素之间的均衡。 展开更多
关键词 水资源承载力 基尼系数 以水定城 水源质供水 空间均衡
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四会市水迳水库灌区水量平衡计算 被引量:1
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作者 吴娱 吴亚敏 《广东水利水电》 2015年第7期26-28,共3页
按灌溉水源进行区分,分别进行各灌溉片区P=90%枯水年的水量平衡计算,论述各灌溉片区供水量与需水量的关系,为水迳水库灌区续建配套与节水改造工程的审批提供依据。
关键词 水迳水库灌区 分水源灌溉 水量平衡
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新安江模型在汤旺河流域洪水预报中的应用 被引量:2
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作者 肖兴涛 张鹏远 张淑霞 《黑龙江水利科技》 2012年第1期41-43,共3页
介绍了新安江模型发展历程,以及模型结构和原理,系统说明了模型参数类型和模型优化方法,通过实例运用三水源新安江模型采用分层分析的方法对模型的参数进行率定,对汤旺河流域日流量过程进行了模拟,模拟分析表明,新安江模型在东北地区洪... 介绍了新安江模型发展历程,以及模型结构和原理,系统说明了模型参数类型和模型优化方法,通过实例运用三水源新安江模型采用分层分析的方法对模型的参数进行率定,对汤旺河流域日流量过程进行了模拟,模拟分析表明,新安江模型在东北地区洪水预报中还是能很好地应用。 展开更多
关键词 新安江模型 参数 产流 蒸散发 分水源 汇流 洪水预报 汤旺河
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Resource allocation based on fairness and QoS provisioning for OFDMA-WLAN system 被引量:1
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作者 鲍楠 夏玮玮 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期1-6,共6页
To satisfy different service requirements of multiple users in the orthogo nal frequency division multiple access wireless local area network OFDMA-WLAN system downlink transmission a resource allocation algorithm bas... To satisfy different service requirements of multiple users in the orthogo nal frequency division multiple access wireless local area network OFDMA-WLAN system downlink transmission a resource allocation algorithm based on fairness and quality of service QoS provisioning is proposed. Different QoS requirements are converted into different rate requirements to calculate the QoSs atisfaction level.The optimization object is revised as a fairness-driven resource optimization function to provide fairness. The complex resource allocation problem is divided into channel allocation and power assignment sub-problems. The sub-problems are solved by the bipartite graph matching and water-filling based method.Compared with other algorithms the proposed algorithm sacrifices less data rate for higher fairnes and QoS satisfaction.The sim ulation results show that the proposed algorithm is capableo fp rovi ding QoS and fairness and performs better in a tradeoff among QoS fairness and data rate. 展开更多
关键词 QOS quality of service satisfaction level fairness driven function b ipartite graph matching water-f i lling resource allocation
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Stable Isotope Technique——An Advanced Technology in Ascertaining Plant-Water Relations 被引量:1
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作者 邢丹 杨万荣 +3 位作者 蓬桂华 苏丹 廖芳芳 韩世玉 《Agricultural Science & Technology》 CAS 2014年第3期338-343,351,共7页
Some key terms and relevant standard related with stable isotope tech- nique were introduced, and the determination of carbon, hydrogen and oxygen, the three stable isotopes in water, as well as their isotope effect w... Some key terms and relevant standard related with stable isotope tech- nique were introduced, and the determination of carbon, hydrogen and oxygen, the three stable isotopes in water, as well as their isotope effect was discussed. Appli- cations and advances of stable isotopes were stated mainly from plant water source, water use efficiency, the most active water adsorption region in root system and water resources utilization differences among different species in plant communi- ty. In addition, some existing problems in investigating the plant-water relations by using stable isotope technique were put forward. In this study, we aimed to promote the sustainable development of stable isotope technique in the research of plant water utilization and in the field of ecology in China. 展开更多
关键词 Stable isotope Plant water source Water use efficiency
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A multi-objective fuzzy optimization model for cropping structure and water resources and its method 被引量:3
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作者 马建琴 陈守煜 邱林 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期5-10,共6页
Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this... Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development. 展开更多
关键词 cropping structure multi objective fuzzy optimization fuzzy deciding weight agricultural water resources
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Pollution of Environmental Endocrine Disrupting Chemicals(EDCs) in Water and Its Adverse Reproductive Effect on Fish 被引量:3
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作者 孟顺龙 宋超 +3 位作者 范立民 裘丽萍 陈家长 徐跑 《Agricultural Science & Technology》 CAS 2014年第3期463-469,共7页
Environmental endocrine disrupting chemicals (EDCs), commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, ... Environmental endocrine disrupting chemicals (EDCs), commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them. 展开更多
关键词 Environmental endocrine disrupting chemical Water body Pollution situ-ation FISH Damage of reproduction
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Effects of Exogenous Abscisic Acid and Water Stress on the Growth Response of Subterranean Clover of Different Genotypes
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作者 许兴 郑国琦 +1 位作者 邓西平 Hipolito MEDRANO 《Acta Botanica Sinica》 CSCD 2002年第12期1425-1431,共7页
The response of subterranean clover ( Trifolium subterraneum L.) to different abscisic acid (ABA) concentrations (10 -6 , 10 -5 , 10 -4 mol/L) in nutrient solution and to water stress were studied in g... The response of subterranean clover ( Trifolium subterraneum L.) to different abscisic acid (ABA) concentrations (10 -6 , 10 -5 , 10 -4 mol/L) in nutrient solution and to water stress were studied in growth room. Six cultivars of contrasting yield capacity were compared. Plants remained growing in Hoagland solution or pots until at least four full_developed leaves appeared. The ABA was then applied and the fresh weight, leaf number and length of the largest root were measured at 1, 4, 7 and 11 d after ABA treatment. The above parameters were also measured at 15 d under water stress. In all the tested genotypes ABA caused similar reduction in these growth parameters, as well as a significant decrease of leaf water potential which was dependent on ABA concentration. The average growth reduction after 11 d under 10 -4 mol/L ABA coincided with the range of these crops under water stress in pot experiments. On average of the different genotypes, leaf number, area of full_developed leaf and the dry weight per plant decreased by about 50% whereas the root/shoot ratio increased by 80%.The genotype variation and ranking for this treatment were rather similar to the same genotypes in pot experiments. The genotypes, Clare, Nuba and Seaton Park, showed the best results under both control and ABA treated conditions and water stress conditions. The similarity between the response to ABA in nutrient solution and to water stress opens the possibility to use this approach as a way to quantify the drought resistance of subterranean clover genotypes. 展开更多
关键词 Trifolium subterraneum water stress abscisic acid nutrient solution GROWTH
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Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the South-to-North Water Diversion Project (Middle Route), China 被引量:12
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作者 殷大聪 郑凌凌 宋立荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期531-540,共10页
One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR ... One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01×10^6 ind./L, and the highest value was 14.72 ×10^6 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiseus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance ofStephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR. 展开更多
关键词 Danjiangkou Reservoir PHYTOPLANKTON South-to-North Water Diversion Project EUTROPHICATION
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Complex patterns of precipitation and extreme events during 1951-2011 in Sichuan Basin, Southwestern China 被引量:4
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作者 ZHOU Xiang-yang LEI Wen-juan 《Journal of Mountain Science》 SCIE CSCD 2018年第2期340-356,共17页
Sichuan Basin is located in southwestern China and affected by a complex water vapor (WV) sources. Here, the spatial and temporal patterns of precipitation and extreme events are investigated by six indices of World... Sichuan Basin is located in southwestern China and affected by a complex water vapor (WV) sources. Here, the spatial and temporal patterns of precipitation and extreme events are investigated by six indices of World Meteorology Organization Commission, including annual precipitation total (AP), maximum daily precipitation (Maxld), intensity of rainfall over 1 mm/d (IR1), maximum and mean consecutive dry days (Max CDD, Mean CDD) and coefficient of variance. Based on 24 daily precipitation time series from 1951 to 2o11, Mann-Kendall test is employed to quantify the significant level of these indices, from which the classification of precipitation change and its spatial patterns are obtained. Meanwhile, the probability distributions of these indices are identified by L-moment analysis and the Goodness-of-fit test, and the corresponding values are calculated by theoretical model at different return periods. The results reveal that the western basin displays normal drought: less AP and precipitation intensity while longer drought. The southern basin shows normal increase: larger AP and precipitation intensity but shorter CDD. However, in hilly region of the central basin and the transition zone between basin and mountains, precipitation changes abnormally: increasing both drought (one or both of Mean CDD and MaxCDD) and precipitation intensity (one or both of Maxld and trend of AP is. Probability IR1) no matter what the distribution models also demonstrate the complex patterns: a negative correlation between Maxld and Max CDD in the west (R2≥0.61) while a positive correlation in the east (R2≥0.41) at all return periods. These patterns are induced by the changes in WV sources and the layout of local terrain. The increase of WV in summer and decrease in spring leads to the heavier rainfall and longer drought respectively. The large heat island effect of the basin contributes to a lower temperature in transition zones and more precipitation in the downwind area. These results are helpful in reevaluating the risk regionally and making better decisions on water resources management and disaster prevention. 展开更多
关键词 Extreme precipitation events CLIMATECHANGE Sichuan Basin Trend analysis Probability distribution
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Stream water quality and its influencing factor in lower order streams in upriver sections of Ashihe River 被引量:3
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作者 GUO Bao-qin WANG Qing-cheng +1 位作者 YU Hong-li Paul E Mou 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期181-186,共6页
For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams (1 st-5th) of Ashihe Ri... For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams (1 st-5th) of Ashihe River continuum in Maoershan Experimental Forest of Northeast Forestry University, Sharlgzhi City, Heilongjiang Province, China. The indexes of stream water quality, i.e., the pH, dissolved oxygen(DO), turbidity, temperature, PO43-P, NO3-N and NH4^+-N concentrations, total dissolved inorganic nitrogen (TDIN-N, including concentrations of NO3^+-N and NH4^+-N), and total phosphorus (inorganic and organic phosphorous, TP) were measured and analyzed. The stream order, related environmental settings and land-use type were recorded for each sampling location. The indexes of stream water quality at different locations with different stream orders and land use types were compared by ANOVA analysis. The indexes of stream water quality at different sampling locations were analyzed by Hierarchical cluster analysis. Result showed that water quality had significant difference in different stream orders and land use types; some locations with different stream features (stream order and land use type) were grouped into same clusters, indicating that random disturbances produced the variations in water quality, which made the spatial variances of stream water quality inconsistent with the general rules. 展开更多
关键词 Stream water quality Land-use Stream order Hierarchical cluster analysis
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Study on the Multi-dimension Evaluation Index System of Agricultural Water Resources in Liaoning Province 被引量:2
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作者 陈金良 石丽忠 《Agricultural Science & Technology》 CAS 2013年第5期780-782,共3页
[Objective] This study aimed to establish the multi-dimensional evaluation index system of agricultural water resources in Liaoning Province. [Method] Delphi method in conjunction with AHP method was adopted to establ... [Objective] This study aimed to establish the multi-dimensional evaluation index system of agricultural water resources in Liaoning Province. [Method] Delphi method in conjunction with AHP method was adopted to establish the multi-dimensional evaluation index system of agricultural water resources in Liaoning Province, and all the indexes in each hierarchy were ranked overall according to their weights. [Result] There were three hierarchies in this index system, totally including 21 indexes, among which water resource exploitation and utilization rate, sewage treatment rate and utilization of available water resources were the three crucial factors influencing the sustainable development. [Conclusion] This evaluation index system can reflect the true sustainable situation of the agricultural water resources in Liaoning Province. 展开更多
关键词 Delphi method Analytic hierarchy process(AHP) method Agricultural water resources Index system
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Humble View on Soil Water Resources 被引量:3
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作者 CHENZHI-XIONG ZHOULIU-ZONG 《Pedosphere》 SCIE CAS CSCD 1993年第3期261-268,共8页
Soil water is one of renewable water resources.Some properties of soil water concerning with its availability to plant are briefly described.An equation for estimating the amount of soil water resource is presented.Ba... Soil water is one of renewable water resources.Some properties of soil water concerning with its availability to plant are briefly described.An equation for estimating the amount of soil water resource is presented.Based on the evaporation demand of atmosphere,the evaluation coefficient for soil water resource is suggested. 展开更多
关键词 RESOURCE soil water
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Some Problems of Irrigation Water Management in Lower Cheliff Plain (Algeria) 被引量:1
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作者 Abdelhamid BradaI Abdelkader Douaoui Tarik Hartani 《Journal of Environmental Science and Engineering(A)》 2012年第3期271-278,共8页
In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the... In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the balance between supply and demand. The two surface water resources, Gargar and Merdjet Sidi Abed dams, do not satisfy the requirements of agriculture water. According to the National Office of the Irrigation and Drainage data, the quantity of allocated water is never distributed; the difference between allocated water and drop water can also exceed 20%, and then, another problem of management is that the water losses in the distribution can reach 20% again. The shortage irrigation water resource allocated has constrained the farmers to use groundwater. The chemical analysis of 56 simples to this water showed a significant chemical diversity in the compositions. There is a high salinity risk (C3 class) or very high risk (C4 class) of soil salinisation. A space chart distribution to the EC water probability to exceed 2.25 dS/m interpolated by the indicator kriging method showed that 78% of the groundwater surface presents a significant probability to exceed this limit. The average value of the SAR (sodium adsorption ratio) is lower than 10 that indicates a moderate risk of sodisation. This observation is in contradiction with the high values of the SAR measured in the soil solution. The approach of residual alkalinity (RSC) shows that a good number of drillings analyzed presents a positive sign RSC (RSC 〉 0). This water presents a real danger of sodisation. They have a low salinity, which, for a farmer, does not present any danger. 展开更多
关键词 Management water irrigation GROUNDWATER water quality.
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Optimal allocation of watershed management cost among different water users 被引量:2
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作者 Wang Zanxin Margaret M. Calderon 《Ecological Economy》 2006年第3期245-250,共6页
The issue of water scarcity highlights the importance of watershed management. A sound watershed manage- ment should make all water users share the incurred cost. This study analyzes the optimal allocation of watershe... The issue of water scarcity highlights the importance of watershed management. A sound watershed manage- ment should make all water users share the incurred cost. This study analyzes the optimal allocation of watershed management cost among different water users. As a consumable, water should be allocated to different users the amounts in which their marginal utilities (MUs) or marginal products (MPs) of water are equal. The value of MUs or MPs equals the water price that the watershed manager charges. When water is simultaneously used as consumable and non- consumable, the watershed manager produces the quantity of water in which the sum of MUs and/or MPs for the two types of uses equals the marginal cost of water production. Each water user should share the portion of watershed management cost in the percentage that his MU or MP accounts for the sum of MUs and/or MPs. Thus, the price of consumable water does not equal the marginal cost of water production even if there is no public good. 展开更多
关键词 Consumable Non-consumable Optimal allocation Watershed management cost
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