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1.
Cost-effectiveness of groundwater conservation measures: A multi-level analysis with policy implications 总被引：1，自引：0，他引：1
Groundwater in Spain, as in other arid and semiarid countries worldwide, has been widely used in the expansion of irrigated agriculture. In the Spanish Mancha Occidental aquifer, the excessive, and sometimes illegal, water abstraction for irrigation has promoted outstanding socioeconomic development in the area, but it has also resulted in exploitation of the aquifer and degradation of valuable wetlands. Water policies implemented in the region have not yet managed to restore the aquifer and face strong social opposition. This paper uses a multi-scale modeling approach to explore the environmental and socio-economic impacts of alternative water conservation measures at the farm and basin levels. It also analyzes their comparative cost-effectiveness to help policy makers identify the least costly policy option for achieving the goal of the Mancha Occidental aquifer's sustainability. To conduct this analysis, a Mathematical Programming Model has been developed to simulate: the closing-up and taxed-legalization of unlicensed wells, uniform volumetric and block-rate water prices, water quotas, and water markets. Aggregate results show that net social costs are not substantially different across policy option, so none of the considered policy options will be clearly more cost-effective than the others. However, there are significant differences between private and public costs (at the farm and sub-basin levels), which will be critical for determining the application in practice of these policies. Results show that controlling illegal water mining (through the legalization of unlicensed wells) is necessary, but is not sufficient to recover the aquifer. Rather, effective water management in this area will require the implementation of other water management policies as well. Among them, uniform volumetric and block-rate water pricing policies will entail the lowest net social cost, but will produce important income losses in the smallest and most water-intensive farms, which might put at risk the viability of these farms and the social acceptance of the policies. Further investigations on social costs, policy enforcement capacity and public participation in water management are highly recommended. 相似文献
2.
Ariel Dinar 《Irrigation Science》1993,14(2):47-52
A consequence of water scarcity is that it has enhanced research and development aimed at increasing water use efficiency in irrigated agriculture. Although biological, genetic, and technological achievements may induce potential high levels of water use efficiency, actual observed values may be much smaller. This paper distinguishes between potential and actual water use efficiency measures, and discusses factors and opportunities that may affect actual water use efficiency in irrigated agriculture. These include economic forces, environmental effects, and institutional arrangements, each of which may affect water use decisions at field, farm, regional, and national levels. The paper develops a scheme to generally address differences between private and social considerations that determine water use efficiency decisions. Using this scheme, several examples from California and Israel are provided to support the arguments. The paper concludes that the concept of water use efficiency is much broader than its definition: yield per water applied or transpired. Moreover, determination of water use efficiency levels in irrigated agriculture is a complex issue that requires interdisciplinary considerations. 相似文献
3.
Sithara S. Atapattu 《Agricultural Water Management》2009,96(3):361-373
Agriculture, a century old practice, has rarely been questioned as it is a necessity for feeding the world's population. With the increase in food requirement, the sustainability of upland agriculture has posed threats to downstream and coastal areas of river basins. In South Asia, the coastal population depends on the lower part of the river basin for their livelihood such as agriculture and aquaculture. There have been numerous occasions where downstream areas have suffered as a consequence of ad hoc agricultural development activities upstream. Problems encountered in the downstream coastal areas include river desiccation, groundwater depletion, water pollution and sedimentation, salinization and salt water intrusion, soil erosion and nutrient depletion, and dynamic changes in the coastal wetland systems. The objective of this paper is to evaluate current agricultural practices, existing problems, and their implications downstream. This would facilitate the adoption of the river basin approach in managing water resources focusing on the South Asian region. 相似文献
4.
GIS tools applied to the sustainable management of water resources: Application to the aquifer system 08-29 总被引：2，自引：0，他引：2
A. Calera Belmonte J. Medrano Gonzlez A. Vela Mayorga S. Castao Fernndez 《Agricultural Water Management》1999,40(2-3):207-220
The sustainable exploitation of water resources requires planning and control methods that allow the incorporation of a great number of spatial and temporal variables. Because of its features, a Geographic Information System (GIS) seems the most suitable tool to aid in the management of available hydric resources. In this study, we have developed a specific GIS within the GESMO Project in order to better manage the 08-29 aquifer system (Mancha Oriental). This tool is intended for use by the JCRMO: Junta Central de Regantes de la Mancha Oriental (General Board of Irrigation Users of Eastern La Mancha), the organism responsible for aquifer management.This system is designed to integrate information from different sources, such as remote sensing, fieldwork data or administrative files with the cadastral subplot as a common reference. One of its functions is to expedite the control and monitoring, in real time, of the exploitation plans, which constitute the legal instrument to regulate water extractions. It will allow us to estimate the spatial and temporal distribution of water extractions needed for crops and their irrigation systems. These estimates will be highly valuable for aquifer modelling. The system also permits display of information on maps for easy handling. This visualisation allow users to more readily participate in decision-making processes. 相似文献
5.
An integrated hydro-economic modelling framework to evaluate water allocation strategies II: Scenario assessment 总被引：2，自引：0，他引：2
Biju George Hector MalanoBrian Davidson Petra HellegersLuna Bharati Sylvain Massuel 《Agricultural Water Management》2011,98(5):747-758
In this paper the results of an assessment of the hydrological and economic implications of reallocating water in the Musi sub-basin, a catchment within the Krishna Basin in India, are reported. Policy makers identified a number of different but plausible scenarios that could apply in the sub-basin, involving; supplying additional urban demand from agricultural allocations of water, implementing a number of demand management strategies, changing the timing of releases for hydropower generation, changing the crops grown under irrigation, reducing existing stream flows and allowing for more environmental flows. The framework chosen to undertake this assessment was a simulation model that measures and compares the economic values of water allocation scenarios determined from a water allocation model that accounts for supplies of groundwater and surface water across a number of regions and over a variety of uses. Policy makers are provided with the range of measures on the security of the supply of water and the social costs and benefits of reallocating water between sectors and across regions within the sub-basin. Taking water from agriculture to supply urban users has a greater impact on irrigation supplies during dry years. It was also found that changing the allocation of water between sectors, by taking it away from agriculture had a large positive economic impact on the urban sector. Yet the costs involved in undertaking such a strategy results in a significant loss in the net present value of the scheme. Stream flow reductions, if significantly large (at around 20%), were found to have a large physical and economic impact on the agricultural sector. Implementing water saving strategies in Hyderabad was found to be more cost effective than taking water from agriculture, if rainwater tanks are used to achieve this. Changing the timing of hydropower flows resulted in best meeting of irrigation demand in NSLC and NSRC. Under this scenario, the crops grown under irrigation were found to have a significant economic impact on the sub-basin, but not as large as farmers undertaking crop diversification strategies, ones which result in farmers growing less rice. The security of supplying water to different agricultural zones has significantly improved under this scenario. Finally, releasing water for environmental purposes was found to have only a minor impact on the agricultural sector. 相似文献
6.
严重的干旱和水资源短缺已成为阜新县农业和农村经济发展的瓶颈。通过对阜新县农业基本情况的调查研究,探讨制约其农业和农村经济可持续发展的因素。并提出适合阜新地区的旱作节水农业发展模式,即耕地资源1：4：3：2的利用模式。分析结果表明,该发展模式具有良好的经济效益、社会效益和生态效益。 相似文献
7.
《Agricultural Systems》2001,68(3):215-232
There is still no pan-European assessment of the typology of low-intensity farming systems and of the changes which they are undergoing under current European Union (EU) farm policy. This study examines the variability of farm structure and farming practices of a typical cereal-sheep farming system under continental Mediterranean conditions with the aim of providing regional data of policy relevance. The collection of quantitative and qualitative data was planned with collaborative effort from regional extension agencies and followed the Delphi technique. Arable land in Castile-La Mancha occupied more than 70% of total agricultural land in 1997, the rest being natural pasture, shrub-steppe, and Mediterranean forest. Dry low-intensity arable systems still included a sizeable proportion of fallow to cropped land (20%) or somewhat more than 1,000,000 ha, and the winter cereal stubble was often grazed by sheep. These systems were of low intensity in the sense that they used low inputs per ha, particularly of nutrients and agrochemicals. They involved the exploitation of land, particularly for grazing, on an open and large scale. In this sense, they can also be considered extensive systems. On average, only 20% of arable farmers kept sheep, while 80% of the sheep producers were landless pastoralists. Young farmers tend to be disinclined to became involved in the sheep sector, because of the harsh working conditions of sheep farming operations. Response to new economic circumstances involved the evolution of traditional practices with corresponding lower use of farm labour. Although still low-intensive, these systems can be considered as modified forms of traditional practices which have responded to new technologies and the need to cut labour costs. The new objectives for agriculture in Castile-La Mancha, must create or maintain a way of life that is socially and economically attractive to young farmers, without the acceptance of environmentally damaging practices. These new objectives will require a new regionally-targeted EU aid scheme. In turn, there is a need to understand regional agriculture systems before we can hope to achieve successful policy. 相似文献
8.
已建大型灌区向城市引水是供水对象扩展问题,也是一个关系到区域社会、经济及生态等方面的多目标复杂系统优化问题。运用系统科学原理和方法,根据灌区供水结构调整的需要,基于系统仿真技术建立了灌区供水系统的多目标模拟模型,采用改进层次分析法将多目标问题转化为单目标函数,并提出试验遗传算法对该系统的设计参数和引水运行参数进行优化设计。通过某实际灌区的优化设计表明,该模型可以在保证城市需水要求的同时减小城市引水对农业灌溉的影响,从而提高灌区水资源的利用率,进一步发挥灌区水资源应有的经济效益和社会效益。 相似文献
9.
山东省是农业大省,农业用水占总用水的70%,而省内各地区自然条件、水资源条件、农业结构及社会经济水平差异较大,对节水农业的发展要求各不相同.利用2000-2005年期间的农业种植结构数据资料和社会经济水平(农民年均人收入值)对山东省17地市发展节水农业的节水灌溉技术方式进行了探讨.数据显示山东各地小麦、玉米和蔬菜种植占据主导,而社会经济水平相对较低,对大田作物仍应以发展低压管道灌溉技术并辅以田间节水方式为主,蔬菜种植应力推高效节水技术方式,控制和减少腾发耗水量.各地市采用节水灌溉技术方式也应各有侧重. 相似文献
10.
少雨干旱、水资源短缺和传统的粗放型耕作模式成为制约昌图县农业可持续发展的突出问题。实现农业可持续发展必须大力推广保护性耕作技术。介绍昌图县水资源严重短缺和风蚀日益严重的现状,论述实施保护性耕作技术的重要作用,提出推广保护性耕作过程中需要解决的主要问题,并对实施保护性耕作的社会、生态和经济效益进行详细分析。 相似文献
11.
F. Martí n de Santa Olalla Ma as A. Brasa Ramos C. Fabeiro Cort s D. Fern ndez Gonz lez H. L pez C rcoles 《Agricultural Water Management》1999,40(2-3):195-205
The great expansion of irrigated lands using groundwater has often caused the exploitation of aquifer reserves beyond their recharge capacity. The development of management tools which can harmonize resource exploitation with reserve sustainability is the objective of an interesting experience being accomplished in the aquifer 08.29 in Mancha Oriental, Spain. This paper offers a summary of this ongoing project (GESMO), pointing out the specific role of the Irrigation Advisory Service. The general objective of the project is to create an integrated and integral management system of the aquifer as well as to prepare appropriate techniques for its adequate exploitation. Integral management means that both supply and demand management are considered, including the socio-economic and environmental perspectives. The concept of integrated management implies that the process must involve the majority of economic and social agents affected.
Management is founded on a Decision Support System (DSS) which takes into consideration different possible options. The DSS must contemplate the impacts on the environment, mainly the aquifer reserve losses and the increase of nitrates concentration in groundwater. The project directly affects more than 5000 agricultural users, irrigating about 100 000 ha with the aquifer water resources, as well as the whole population living in this region. Results of this project, including irrigation technologies developed may be useful for other areas in the Mediterranean Basin where similar cases occur. 相似文献
12.
在界定节水农业综合效益概念和内涵的基础上,从经济、环境、社会三方面提出节水农业综合效益价值评估指标体系,应用基于单位化约束条件的综合集成赋权法确定指标权重,建立以货币为衡量标准的节水农业综合效益评估模式。以皂河灌区为例,对节水农业经济、环境、社会及综合效益进行估算,即估算节水农业实施后年效益流量,分析节水农业效益价值动... 相似文献
13.
J.E. Ayars R.B. Hutmacher R.A. Schoneman R.W.O. Soppe S.S. Vail F. Dale 《Irrigation and Drainage Systems》1999,13(4):321-347
In situ use of ground water by plants is one optionbeing considered to reduce discharge of subsurfacedrainage water from irrigated agriculture. Laboratory, lysimeter, and field studies havedemonstrated that crops can use significant quantitiesof water from shallow ground water. However, moststudies lack the data needed to include the crop wateruse into an integrated irrigation and drainage watermanagement system. This paper describes previousstudies which demonstrated the potential use of groundwater to support plant growth and the associatedlimitations. Included are results from three fieldstudies which demonstrated some of the managementtechniques needed to develop an integrated system. The field studies demonstrated that approximately 40to 45% of the water requirement for cotton can bederived from shallow saline ground water. Thatregulation of the outflow will result in increasinguse. Implementation of integrated management ofirrigation and subsurface drainage systems is a viableand sustainable alternative in the management ofsubsurface drainage water from arid and semi-aridareas only if soil salinity can be managed and if thesystem is profitable. 相似文献
14.
Filiz Dadaser-Celik Patrick L. Brezonik Heinz G. Stefan 《Irrigation and Drainage Systems》2008,22(1):47-66
Develi Basin is a semi-arid basin in central Turkey where water sustains both irrigated agriculture and an internationally
important wetland, the Sultan Marshes. Agricultural and environmental changes in the Develi Basin have occurred since irrigation
management was transferred in 1994 from a state authority (DSI) to irrigation associations (Kovalı and Ağcaaşar IAs). In this
paper we evaluate the practices of the IAs using extensive data from interviews with farmers and IA officials, as well as
data from reports prepared by DSI and the IAs, using comparisons with case studies reported in the scientific literature.
Irrigated areas and surface water use in the Develi Basin showed significant fluctuations from 1995 to 2003. The area allocated
to high water-consuming plants increased. Maintenance activities became dependent on fee collection rates. Quality of the
irrigation water did not changed significantly. Ground-water levels, flow rates from springs, and water levels in the Sultan
Marshes all dropped. Overall analyses indicate that the water requirements of the Sultan Marshes have not been met, while
water use for irrigation has been effective but not efficient. To reconcile agricultural and wetland water requirements, a
basin-wide approach in water planning is recommended. Amounts of water to be allocated to the IAs and wetlands need to be
clearly defined. DSI has to monitor canal maintenance by the IAs more closely, and IAs need to be given more responsibilities
for future rehabilitation of the canals. Realistic water pricing, increased reliability of irrigation scheduling, higher on-farm
irrigation efficiency, and in the long-term, modernization of the irrigation system need to be considered. 相似文献
15.
Agricultural systems as well as other ecosystems generate ecosystem services, i.e., societal benefits from ecological processes. These services include, for example, nutrient reduction that leads to water quality improvements in some wetlands and climatic regulation through recycling of precipitation in rain forests. While agriculture has increased ‘provisioning’ ecosystem services, such as food, fiber and timber production, it has, through time, substantially impacted other ecosystem services. Here we review the trade-offs among ecosystem services that have been generated by agriculture-induced changes to water quality and quantity in downstream aquatic systems, wetlands and terrestrial systems. We highlight emerging issues that need urgent attention in research and policy making. We identify three main strategies by which agricultural water management can deal with these large trade-offs: (a) improving water management practices on agricultural lands, (b) better linkage with management of downstream aquatic ecosystems, and (c) paying more attention to how water can be managed to create multifunctional agro-ecosystems. This can only be done if ecological landscape processes are better understood, and the values of ecosystem services other than food production are also recognized. 相似文献
16.
Analysis on groundwater table drawdown by land use and the quest for sustainable water use in the Hebei Plain in China 总被引：1，自引：0，他引：1
《Agricultural Water Management》2005,75(1):38-53
Increased water use in the Hebei Plain during the last decades has caused serious groundwater level decline and many geological problems which have become the biggest threat to social–economic sustainability. Thus, to determine the factors resulting in the groundwater decline and to develop a practical plan for long-term groundwater use appear to be necessary in this region. In this paper, a water balance model is used in conjunction with regression techniques to estimate the groundwater recharge coefficient and the specific yield (defined as the ratio of the volume of water that a saturated rock or soil will release by gravity drainage to the volume of rock or soil) and the groundwater withdrawn by different water use sectors and the corresponding drop in the water-table are analyzed. The decline in water-table by different crops and water economic benefit of crops are discussed in detail in order to suggest sustainable use of groundwater resources in the Hebei Plain. Finally, sample policy scenarios are developed to show how groundwater in the Hebei Plain could be used in a sustainable manner. In our study, it is found that agriculture is the major consumer of groundwater, with about 85% of the total groundwater withdrawals, and groundwater depletion is mainly caused by agricultural water use. Production of winter wheat exerts a great negative influence on the groundwater system. Winter wheat is the most water consuming crop and result in significant decline of groundwater table. Water economic benefit of winter wheat is lower than that of other crops and withdrawing winter wheat sown area is rational option to make sustainable use of groundwater. With far-sighted and regional planning, the limited water resource can be used sustainably to generate maximum social benefits. This paper will provide information necessary for land-use planning in a severe water shortage region where farmland is mainly irrigated by groundwater. 相似文献
17.
华北地区节水农业标准初探 总被引：1，自引：0，他引：1
本文是总理基金课题“华北地区节水型农业技术体系研究与示范”的第四专题:“华北地区节水型农业分区与对策研究”中的一个研究内容,节水农业是在维持或提高农作物单产或总产的前提下,节约灌溉用水的农业。但是节水节到什么程度才算是节水衣业,国内外都没有一个可操作的标准,这就给华北地区发展节水型农业的宏观决策带来困难。本文通过研究,提出了一个包括效益指标、需水指标和工程指标三个层次的节水农业标准指标体系,并对由此出现的一些问题进行了讨论。 相似文献
18.
A. Domínguez J.M. TarjueloJ.A. de Juan E. López-MataJ. Breidy F. Karam 《Agricultural Water Management》2011,98(9):1451-1461
In both arid and semi-arid areas the use of saline water for irrigation is a common practice, even though it may cause a drop in crop yield and progressive soil salinization. In order to determine the most suitable irrigation strategy for higher yield, profitability, and soil salinity management of certain crops, the MOPECO-Salt Model has been developed. This model was first validated in the Eastern Mancha Agricultural System in Albacete (Spain) through a test carried out on onion crop in April-September 2009, where the simulated yield was 2% lower than the observed one. The model was then tested at Tal Amara Research Station in the Central Bekaa Valley Agricultural System (Lebanon) using data from a 5-year experiment on the effects of deficit irrigation on two cultivars of potato (Spunta: July-October 2001, and June-September 2002; and Agria: March-August 2004, 2005, and 2007). Furthermore, these results were compared with those obtained through AquaCrop, which does not currently assess crop response to salinity. Differences between observed and simulated yields were lower than 3% for MOPECO-Salt and up to 12% for AquaCrop. According to findings from simulations, the irrigation strategies without leaching fraction employed in both areas are remediable since the off-season rainfall is sufficient to wash out soluble salts supplied with irrigation water. Results showed that as much as 14.4% water could be saved when this strategy was adopted for onion crops. 相似文献
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20.
"民工"从语词上界定可以理解为:农民和工人双重身份,本文放在传统农业向现代农业转变的大背景下,着重考察了游离在城乡之间的农民工主题身份的认定,及其未来的阶级、阶层走向,按照断裂社会的运作逻辑,经过分化重组的当下社会必定会出现新的阶级、阶层.这些阶级、阶层与传统阶级、阶层有什么区别和联系,农民工如果被假定为工人阶级而客观存在.那么这些生活在城市里农民能否获得市民身份的认同?对这些问题的回答有利于我们走出"城乡二元格局"的困境,有利于构建更加稳定、和谐的社会主义新农村. 相似文献