共查询到20条相似文献，搜索用时 15 毫秒
1.
Water resources are essential to human development processes and to achieve the Millennium Development Goals that seek, inter alia, to eradicate extreme poverty and hunger, achieve universal literacy, and ensure environmental sustainability. Expanding irrigation is essential to increase agricultural production, which is needed to achieve economic development and attain food security in much of sub-Saharan Africa. Water resources and irrigated agriculture are not developed to their full potential. Currently less than 4% of renewable water resources in Africa are withdrawn for agriculture. Barriers include the lack of financial and human resources to build irrigation and related rural infrastructure and acquire agricultural technology, and inadequate access to markets. This constrains progress towards poverty reduction. We examine the linkages between agricultural water, education, markets and rural poverty through a review of published studies. We argue that, linking agricultural water, education, and market interventions, which are so often implemented separately, would generate more effective poverty reduction and hunger eradication programs. Investments in agricultural water management and complementary rural infrastructure and related policies are the pathways to break the poverty trap in smallholder African agriculture. 相似文献
2.
Pathways to breaking the poverty trap in Ethiopia: Investments in agricultural water, education, and markets 总被引：1，自引：0，他引：1
Munir A. Hanjra Tadele Ferede Debel Gemechu Gutta 《Agricultural Water Management》2009,96(11):1596-1604
Investments in agricultural water management should complement or strengthen the livelihood and coping systems of the rural poor, and should thus be instrumental for breaking the poverty trap in Ethiopia. Underdeveloped water resources constrain progress towards poverty reduction. We examine linkages and complementarities between agricultural water, education, markets and rural poverty through an empirical study using household level data from selected villages in southern Ethiopia. We show that investments in irrigation can contribute to poverty reduction, but the poverty reducing impacts of irrigation water are greater when human capital and rural markets are well developed. The size of landholding, access to irrigation water, on-farm land and water conservation practices, literacy of the household head, and years of education of adults are all significant determinants of household welfare, and thus potential pathways for reducing poverty. Expansion of cultivated land, particularly irrigated land, universal literacy, and an extra school year for adults all reduce poverty, but reductions in poverty are greater when irrigation is combined with universal literacy. These findings call for simultaneous investments in agricultural water, education, markets and related policy support measures for reducing poverty in smallholder agriculture in Ethiopia. 相似文献
3.
《Agricultural Water Management》2005,76(1):24-35
Due to the increasing demand for food and fiber by its ever-increasing population, the pressure on fresh water resources of Pakistan is increasing. Optimum utilization of surface and groundwater resources has become extremely important to fill the gap between water demand and supply. At Lahore, Pakistan 18 lysimeters, each 3.05 m × 3.05 m × 6.1 m deep were constructed to investigate the effect of shallow water tables on crop water requirements. The lysimeters were connected to bottles with Marriotte siphons to maintain the water tables at the desired levels and tensiometers were installed to measure soil water potential. The crops studied included wheat, sugarcane, maize, sorghum, berseem and sunflower. The results of these studies showed that the contribution of groundwater in meeting the crop water requirements varied with the water-table depth. With the water table at 0.5 m depth, wheat met its entire water requirement from the groundwater and sunflower absorbed more than 80% of its required water from groundwater. Maize and sorghum were found to be waterlogging sensitive crops whose yields were reduced with higher water table. However, maximum sugarcane yield was obtained with the water table at or below 2.0 m depth. Generally, the water-table depth of 1.5–2.0 m was found to be optimum for all the crops studied. In areas where the water table is shallow, the present system of irrigation supplies and water allowance needs adjustments to avoid over irrigation and in-efficient use of water. 相似文献
4.
为实现纵向岭谷区农业水管理调控,宏观上以流域水资源综合规划为基础,从需求入手,采取强化节水措施,提高水的利用效率,抑制需水的不合理增长,到2030年农田有效灌溉程度达到32%,灌溉水利用系数提高到0.581,农业灌溉需水总量控制在89.8亿m3,需水年均增长率仅0.52%,以MKIE BASIN模型的配置结果显示,各规划水平年能达到水资源供需平衡;微观上应建立数字流域工程,提高对流域雨水工情的实时监测.推行农业高效节水灌溉制度,建立和完善包括实时灌溉预报、渠系动态配水、实时信息采集和预报修正、灌区空间信息管理等内容的流域单元农业灌溉用水及水资源的实时调度系统,利用水资源配置成果与短期实时调度相结合,实现流域单元的农业高效用水调控. 相似文献
5.
吴丽霜 《国际沙棘研究与开发》2017,(1)
本文以辽宁海滨灌区为例,以现状灌溉制度为基础,将《辽宁省行业用水定额》与《辽宁省各种作物灌溉制度分析》有机结合,确定灌溉定额.水量平衡分析过程中,将灌溉面积和可供水量分别分区,充分利用区间径流来减少水库供水,实现优化水资源配置,为灌区水资源科学合理利用提供决策性依据,也可供类似工程设计参考. 相似文献
6.
为了精准指导农田灌溉,合理优化渠系输配水,提高水资源的利用率、灌区的管理水平和总效益,对灌区用水计划的编制方法展开了理论研究.将用水计划的编制过程概括为实时灌溉预报和渠系配水两部分,分别进行归纳整理和分析.在对国内灌区用水计划的编制方式进行了解的基础上,着重介绍了利用土壤水分平衡方程进行实时灌溉预报的方法,总结各参数预... 相似文献
7.
Non-conventional water resources and opportunities for water augmentation to achieve food security in water scarce countries 总被引：1，自引：0，他引：1
Given current demographic trends and future growth projections, as much as 60% of the global population may suffer water scarcity by the year 2025. The water-use efficiency techniques used with conventional resources have been improved. However, water-scarce countries will have to rely more on the use of non-conventional water resources to partly alleviate water scarcity. Non-conventional water resources are either generated as a product of specialized processes such as desalination or need suitable pre-use treatment and/or appropriate soil–water–crop management strategies when used for irrigation. In water-scarce environments, such water resources are accessed through the desalination of seawater and highly brackish groundwater, the harvesting of rainwater, and the use of marginal-quality water resources for irrigation. The marginal-quality waters used for irrigation consist of wastewater, agricultural drainage water, and groundwater containing different types of salts. In many developing countries, a major part of the wastewater generated by domestic, commercial, and industrial sectors is used for crop production in an untreated or partly treated form. The protection of public health and the environment are the main concerns associated with uncontrolled wastewater irrigation. The use of saline and/or sodic drainage water and groundwater for agriculture is expected to increase. This warrants modifications in the existing soil, irrigation, and crop management practices used, in order to cope with the increases in salinity and sodicity that will occur. 相似文献
8.
针对农业水资源优化配置中多目标赋权的不确定性问题,以黑龙江省绰尔屯灌区为研究区域,构建了基于模糊几何加权法的灌区水资源优化配置模型,把多目标规划问题转化为单目标非线性问题,得到了不同权重下不同生育期的灌区水资源最佳配置方案,并通过灌区综合能力评价体系进行比选.结果表明:通过与线性多目标模糊规划模型的对比,模糊几何加权模型可以根据实际情况对不同目标的权重进行调整,得出该条件下的灌区水资源最佳配置方案;当灌水量权重为0.3和经济权重为0.7时为最优方案,水稻产值为8 245万元,分蘖期、拔节期、抽穗期、乳熟期的灌水量分别为1 154.56万、779.12万、539.45万、336.57万m3.验证了模糊几何加权法在灌区水资源优化配置的可行性应用,为灌区农业水资源高效利用提供参考方案和决策支持. 相似文献
9.
Comparing water management in rice-wheat production systems in Haryana, India and Punjab, Pakistan 总被引：1，自引：0，他引：1
Olaf Erenstein 《Agricultural Water Management》2009,96(12):1799-1806
The intensive irrigated rice-wheat systems in the northwest Indo-Gangetic Plains of South Asia are built on a long tradition of canal irrigation and the more recent advent of tubewells. Findings from farm surveys are used to examine water management and water productivity in the rice-wheat belt of India's Haryana State and Pakistan's Punjab province. Attributes of the irrigation sources help explain the widespread interest in groundwater use and the relative demise of canal water use. In each area groundwater now is the main irrigation source, used either solely or in conjunction with surface water. The ownership of tubewells is near universal among the surveyed farms, whereas conjunctive water use is more widespread during the monsoon season, among better endowed farmers and in the Pakistan Punjab. In Pakistan Punjab farmers primarily rely on diesel powered tubewells whereas Haryana farmers mainly use relatively cheaper electric power. Water productivity indicators for rice are markedly lower than those for wheat—largely reflecting significantly higher water inputs in paddy cultivation—but also vary between the study areas and by the prevailing water use, reflecting the limited incentives for farmers to use water wisely. A combination of technological, land use and market based approaches is likely to be most effective in achieving sustainable water management in these intensive cereal systems. 相似文献
10.
Globally, about 10 Mha of agricultural land is lost annually due to salinisation, of which about 1.5 Mha is in irrigated areas. While some climate and management aspects are common to semi-arid regions, the detailed mechanisms and options to secure ecological sustainability and economic viability may vary considerably from case to case. This paper applies a whole of system-water balance to compare irrigation in three semi-arid regions suffering from similar sustainability issues: Rechna Doab (RD), Pakistan; the Liuyuankou irrigation system (LIS), China; and Murrumbidgee irrigation area (MIA), Australia. Soil salinity, lack of adequate water resources and groundwater management are major issues in these areas. The MIA and LIS irrigation systems also suffer from soil salinity and low water-use efficiency issues. These similarities occur in spite of very different climatic and underlying hydrogeological conditions. The key data used to compare these different regions are climate and soils, available water resources and their use, as well as components of the water balance. In addition, the history of water resource development in these areas is examined to understand how salinity problems emerge in semi-arid regions and the consequences for production. Based on the efficiency parameters and the definitions of sustainability, approaches are explored to solve common environmental problems while maintaining economic viability and environmental sustainability for irrigation systems. 相似文献
11.
转变下游引黄灌溉模式合理利用黄 总被引：1，自引：0，他引：1
为了促进黄河水资源的合理、高效开发利用，通过分析黄河下游引黄灌区现状灌溉模式存在的主要问题及日益短缺的黄河水资源供需供形势，提出了引黄灌溉的发展方向和应采取的主要措施，如：建立和完善科学合理的水价形成机制；建立“准水权”促进水权有偿转让和流动等。 相似文献
12.
Frank van Steenbergen 《Irrigation and Drainage Systems》1992,6(2):149-159
In an earlier article in this journal Robert Hecht argued that in the design of small scale irrigation systems a study of the existing land and water rights is essential. This paper suggest that a study of existing land and water rights alone does not suffice, but that the intended changes in water availability have to be taken into account as well. Using examples from a small-scale irrigation project in Balochistan (Pakistan), the paper discusses four categories of changes in water availability, i.e. new development: major increase in available water; marginal increase in available water and integration of independent systems. Each one of these categories has a different impact in terms of changes in land and water rights, changes in the water distribution system and selection of command area. To accomodate these changes close consultation with the water users is required during the development of the scheme, and designs will often evolve incrementally. 相似文献
13.
《Agricultural Water Management》2005,71(3):181-209
Australia is the driest inhabited continent on earth, and pressure on its water resources is already high and increasing. Environmental, social, and economic drivers are forcing horticultural industries in Australia to reassess their use of freshwater resources. Reclaimed water is potentially a major resource for the horticultural industry. In general, however, there has been some apprehension towards using reclaimed water for irrigation, owing primarily to uncertainties related to agricultural sustainability and human health. Here, we consider the current standing of the Australian horticultural industry in terms of its preparedness to use reclaimed water for irrigation. We address issues related to policy, economics, market access, pragmatic directives (such as state and federal guidelines), environmental impact, agronomic sustainability, and public health. From these appraisals, we have attempted to summarise the major impediments to the use of reclaimed water by the Australian horticultural industry. These are: insufficient knowledge of impacts on market access; commitment to provide continuity of quality and supply to markets; implications of substitution of alternative water sources on security of supply; insufficient knowledge of food safety issues; inadequate understanding of consumer perceptions; and uncertainty about pricing of reclaimed water. 相似文献
14.
The feasibility of closing distributary canals at night was investigated in a recently modernized surface irrigation system in Pakistan, the Upper Swat-Pehur High Level Canal system. Increased water supply, greater delivery capacity and the introduction of downstream control potentially allow more flexible service. In the command area of Maira branch of this system, farmers are anyway abandoning night-time irrigation, as they can meet their needs from improved supply during the day. They practice night irrigation only during the times of peak crop water demand. The rotational delivery system, known as warabandi in the sub-continent and Dauran in Arabian countries, has even broken down in the day in some parts of the command area. This is believed to be typical of systems with more than adequate water supply.A simulation study was undertaken using the CanalMan software developed by Biological & Irrigation Department, Utah State University, Utah Logan, USA. Primary data collected in one distributary canal and the two minors connected to it was utilized for simulations. The feasibility of night-time closure depends on the speed of filling and emptying the canal each day, and the time required to meet full irrigation demand during the day. The results show that where canal lengths are less than 5 km, in this system, there is good potential to make savings, which can be realized at system level through reduced demand on supplemental supplies from Tarbela Dam. 相似文献
15.
A measure to evaluate performance in irrigation systems is analyzed using the mean square prediction error concept. In the context of irrigation system management, the term error means the deviation of actual performance from a reference performance. The measure assesses performance in terms of the management objectives of adequacy and dependability of water delivery and an equitable distribution among various water users. It provides an understanding of the management capacity to schedule and distribute water in an irrigation system. Application of the performance measure is demonstrated by evaluating performance of an irrigation system in the Northwest Frontier Province of Pakistan. 相似文献
16.
《Agricultural Water Management》1996,31(3):269-283
Rapid industrial development in the rice-growing regions has increased competition for the scarce water resources. Water reuse (surface and subsurface agriculture drainage water, storm runoff, sewerage effluent and industrial wastewater recycling) is in widespread use as a method of supplementing the paddy water supply, therefore, there is a need to clarify its effects on the paddy system water balance and riceland ecosystem. Field data and simulation results from a complex runoff model (created on a daily basis), were used to estimate the water balance and assess the effects on the irrigation system of a water shortage area in Niigata Prefecture, Japan. For three years (1991–1993), the average water reuse component was within the range 14∼ 15% of the total irrigation water supply. Apart from meeting the water needs at peak demand periods, water reuse is a quick-response water supply solution during dry spells, increasing both the water reliability and crop security. To understand the impact of water reuse on the riceland ecosystem, its effect on total phosphorus (T-P), total nitrogen (T-N), suspended solids (SS), and chemical oxygen demand (COD) was assessed. Blending of the drainage water was done to reduce the irrigation water concentrations, to approximate the traditional dual canal system and to increase farmer satisfaction with the water reuse system. Apart from the fact that the amount of return flow drained out of the irrigation system was reduced when drainage water was reused for irrigation, the effluent load reductions for SS and T-P owing to water reuse were consistently high. Hence, water reuse not only helps meet irrigation water needs, but also aids purification of the agricultural drainage water and preservation of the riceland ecosystem. 相似文献
17.
灌溉回归水的利用与效益分析 总被引：3，自引：0，他引：3
在引黄灌区下游的骨干排水河道上建设提水设施和拦蓄工程,利用灌溉回归水灌溉农田,是合理利用水资源,弥补黄河水源不足,缓解灌区上、下游争水矛盾的一条行之有效的措施,具有十分显著的经济效益和社会效益。 相似文献
18.
Irrigation with saline water: benefits and environmental impact 总被引：24，自引：0，他引：24
Julin Martínez Beltrn 《Agricultural Water Management》1999,40(2-3):183-194
The shortage of water resources of good quality is becoming an important issue in the arid and semi-arid zones. For this reason the availability of water resources of marginal quality such as drainage water, saline groundwater and treated wastewater has become an important consideration. Nevertheless, the use of these waters in irrigated lands requires the control of soil salinity by means of leaching and drainage of excess water and salt. However, the leaching of salts, soil microelements and agro-chemicals can lower the quality of the drainage water in the irrigation scheme. The irrigation return flows with water or poor quality are a source of pollution of the surface water bodies situated downstream of the drainage outlet. Deep percolation could also contaminate the groundwater. Therefore, irrigation with saline water requires a comprehensive analysis even beyond the area where water is applied. The problem should be treated beyond the scope of the irrigation scheme, taking into consideration the groundwater and downstream surface water resources of the river basin. Consequently, the sustainable use of saline water in irrigated agriculture requires the control of soil salinity at the field level, a decrease in the amount of drainage water, and the disposal of the irrigation return flows in such a way that minimizes the side effects on the quality of downstream water resources. This paper describes the guidelines for a preliminary evaluation of the suitability of water for irrigation and the key factors for salinity control in lands irrigated with saline water. Options to improve the quality of the drainage water, strategies for the reuse of this water and alternatives for disposal of the outflow are also analysed. The final goal is to obtain sustainable agriculture and maintain the quality of the water resources in the river basin. 相似文献
19.
国内外灌溉水利用系数研究进展 总被引：4，自引：0，他引：4
灌溉水利用系数是定量评价灌溉水利用程度的一项指标。正确确定灌溉水利用系数,并利用灌溉水利用系数对灌区用水进行管理,对于农业节水及水资源的可持续利用都至关重要。对国内外灌溉水利用系数方面的研究进行了综述和评价,对本领域的研究前沿进行了展望。 相似文献
20.
Tradable water rights systems are becoming an important way to achieve distributive efficiency for water resources. However, it is not easy for countries or regions to establish water markets due to the existence of various barriers. In early 2002, the Ministry of Water Resources (MWR) of China initiated an experimental project—Building Water-saving Society in Zhangye City. This project was the first of its kind in China. The aim of the project was to establish a new water use rights (WUR) system with tradable water quotas and to reallocate water resources reasonably and efficiently through market-based instruments. This paper presents the research done on the system and water markets. It has been found that that the system is hard to implement well and that WUR trading is not popular. The barriers to implementing a WUR system are social and administrative in nature. WUR trading faces management, legal, administrative, and fiscal barriers. We discuss why these barriers exist and we provide policy recommendations to overcome them. 相似文献