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1.
水泥罐渗罐具有工艺简单,成本低,渗水速率易控制,取材易等优点.罐形以直径和高度相等时的圆柱体、罐壁厚度以2cm、水泥沙子比以1:6为最佳.水泥罐罐渗灌溉技术简单、节水节肥,效益显著,利于保护土壤,提高产量,不受地形条件限制,适合我国国情.  相似文献   

2.
Recent research has showed increasing interest at the vital role of irrigation ponds that plays at biodiversity conservation, and provides ecological functions at a wide range. However, many irrigation ponds were abolished due to the economic and societal transformation in the rural. In particular, small-scale ponds were abolished and rebuilt to other public uses based on the consensus building process among the community. At the same time, civil organizations also launched initiatives to conserve irrigation ponds for its ecological significance or landscape scenery. However, study pertinent to the small scale ponds in the rural setting is largely neglected. This research aims at revealing the current situation of the utilization and management of small irrigation ponds using a case study of Noto Island in Ishikawa Prefecture. It was found that irrigation ponds are still under the traditional co-management of rural community. The most important finding in this study is that the traditional management of pond water use largely contributes to mitigate the harvest loss from natural disasters such as drought in the face of extreme climate. However, irrigation ponds are facing the threat of degradation due to the sharp decrease of farm population and the existing large number of part time farmers. Therefore, the small scale irrigation ponds and pertinent management and water use allotment should be revalued for its functions at a wide range from the biological and ecological functions and human knowledge system to mitigate disaster threats.  相似文献   

3.
民勤绿洲水资源利用中的问题与节水途径   总被引:23,自引:12,他引:11  
石羊河进入民勤盆地的水资源逐年递减,导致绿洲内部地下水的过度超采,从而引起生态环境恶化及农田弃耕、沙化。缺水己严重地威胁着绿洲农业的发展。但是不合理的水资源管理制度、落后的灌溉方法和产业结构等使水资源的利用很不合理,灌溉水的利用率低下。改革目前的水资源管理办法,完善和配套渠系工程和田间工程,选用节水的优良作物品种,调整农业产业结构,推广应用先进的灌溉技术,逐步发展现代节水农业,建立节水型社会是民勤实施可持续发展战略的必由之路。  相似文献   

4.
西线调水工程对水量调出区的环境影响分析   总被引:7,自引:0,他引:7  
介绍了南水北调西线工程新的调水方案 ,工程所在位置及其影响所及的区域。在此基础上 ,从自然环境和社会环境两个方面 ,对南水北调西线工程水量调出区可能产生的主要环境影响问题进行了初步研究 ,包括调水对气候、动植物、水质、水库区及周边地质环境、人群健康等的影响 ,以及水库淹没对社会经济的影响等。其主要结论是 :1对库区、坝址临近地区的气温、降水影响均较小 ,由于库区水汽蒸发量增加对局地降水的贡献率约为 0 .0 0 4~ 0 .0 0 8;对干旱河谷区气候虽有影响 ,但很微弱。 2对生物会产生一定影响 ,主要表现在对渔类区系组成、种群结构等方面。对陆生生物造成一定数量的减少 ,但不会造成生物物种资源的减少。3坝址下游水质比现在有所下降 ,但由于河段所在位置人口密度低 ,污染较轻 ,对水质不会有大的影响。 4淹没损失小 ,移民少。本文可为西线调水工程对环境影响研究提供部分参考依据。  相似文献   

5.
砖罐罐渗技术的优点在于:材料易取,成本低廉,制作工艺简单,节水节肥效益显著。罐渗果园可不择地貌-土壤条件,利用零星水源,分散经营,管理方便,适合在我国中西部山区推广应用。  相似文献   

6.
As the consequence of climate change, water that is received in Australian Murray-Darling Basin wetlands is declining and agricultural water demands are increasing. In order to keep the water use balance between environment protection including wetland protection and irrigation water use, the Australian government adopted a series of reforms in Murray-Darling Basin to address the environmental water shortage problem and encourage irrigators to use water more efficiently and plant high economic value crop. The water trading and cap are two major reforms in this process.In order to match up the environmental water demand such as wetland water use, based on the seasonal rainfall, dam level and environmental water demand, the cap system seasonally allocate how much water the irrigators can access as per water licenses. As the cap dramatically reduced the water access for irrigators, the water trading is aiming to use limited agricultural water more efficiently. The water trading scheme separate the water use right from the land property right and allow Australian farmers to trade their water licenses in the market. Water trading encouraged farmers who plant low value crops such as wheat and canola transfer their water entitles to farmers who plant high value crops such as grape. In the drought seasons, The Australian government can purchase the water licenses from irrigators to increase the environmental flows.This Australian water management system represents the most complicated and effective environmental and agricultural water use management in this world. There are possible many lessons that will help China to better manage the water use for wetland protection and farming practices.  相似文献   

7.
受大量的外调水资源和人工灌溉的影响,干旱扬水灌区的水土环境变迁过程具有独特性,其对区域环境要素的响应是长期、潜在而缓慢的,该过程可通过科学的评估与分析描述其发展的趋势。评价过程是否合理,评价结果是否准确是灌区可持续发展的关键。通过应用改进的层次分析法,对干旱扬水灌区水土环境变迁响应进行了评价。结果表明:干旱扬水灌区水土环境变迁响应因子都属于"微敏感"因子;地表水对水土环境的变迁响应相对较为强烈,其次为地下水、区域气候,而土地利用最为迟缓; 18个响应因子中最为敏感的是灌区提水量及灌溉用水量,次之为地下水水位及回归水水质。该评价模型的评价结果与当前灌区水土环境变化现状相吻合,验证了改进层次分析法在干旱扬水灌区水土环境变迁响应评价中的有效性和可操作性,可为灌区的建设和管理提供科学合理的参考依据。  相似文献   

8.
We look at the beliefs of the population in North Cameroon concerning water, fish and water spirits in the context of the construction of a dam (1979) and of a flood embankment for a rice irrigation scheme financed by the World Bank. These operations caused a drought that had severe effects on the environment and the inhabitants' economic activities. Acknowledging the new approaches within development and ecological development thinking, we emphasize that local people are part of their environment, and that the environment and people's use of the ecosystem ought to be regarded as a functional unit. Our main argument is that the success of environmental strategies requires that the unequal power relations between the different actors and agencies and the perceptions of policymakers and NGOs be analysed and examined regularly in the course of a project to test their aims and integrity. In addition, the positions of beings and cosmological entities, which in the eyes of the population are 'actors of power to be reckoned with', like the water spirit, should also be included. The hidden agendas of all actors can be as difficult as the water spirit ( Maama Waata ) itself, by which we mean that hidden agendas are equally a part of reality as is the water spirit, even if they are not visible at first.  相似文献   

9.
中国沙漠和沙地的资源优势与农业发展   总被引:7,自引:3,他引:4  
人口、粮食、土地之间的矛盾已成为今后我国几十年的主要问题。我国后备土地资源的68%分布在干旱、半干旱地区,其中沙漠和沙地面积辽阔,类型繁多,涉及212个县(旗)、48×106人。我国的沙漠和沙地具备适度开发利用的水资源依托,具有灌溉、雨养和高寒农业等特殊环境,是栽培作物和养殖家畜的集中区,许多尚无饲养或尚无栽培种类可以取代的野生动植物具有独特经济价值和高度的抗性。我国的沙地持续利用技术体系已初步建立,形成了一整套具有中国特色的流沙固定技术,结合各地的具体条件创建了许多成功的区域开发治理模式。沙漠和沙地开发必须摆脱传统的农业利用模式,依靠科技进步,多采光、少用水,结合资源条件、市场需求、投资能力,有计划、有步骤地规模开发。  相似文献   

10.
李忆春  陈发虎 《山地学报》2001,19(5):465-469
水资源短缺和生态环境恶化已成为民勤绿洲面临的严重问题。本文在分析民勤盆地水资源特点及开发利用中存在的问题的基础上,本着水资源可持续利用的原则,从加强水资源保护与管理,发展节水农业生产体系,以及开源调水和减少人口等方面,提出了水资源可持续利用途径与措施。  相似文献   

11.
针对“定居兴牧”水源工程勘测设计、建设管理中的难点问题和关键环节,分析和阐述了立项审批、建设资金、建设管理及质量安全三项保障措施,以及建立的坝工建设、工程水文计算及工程地质勘察、工程设计与施工技术体系三项技术支撑,提出了工程规模“择小放大”、泄水建筑物规模“择大放小”、抗震设计“评Ⅶ设Ⅷ”、灌溉模式“择高有压”、地质条件复杂“避让放弃”等技术措施和应把握的原则,建立了“定居兴牧”水源工程技术支撑体系;并针对牧民定居水资源保障和安置模式、水源工程水价及管理、受水区开发规模等问题进行了分析讨论,指出新疆已不具备大规模开发水土资源的条件,采取“集中定居、插花定居、分流转产”三种定居模式,是切合新疆实际的;水源及其配套工程效益的发挥,需要加快饲草饲料基地开发建设,走集约化、现代化发展之路;水价应考虑牧民承受能力和工程良性运行的需要,可采取财政扶持、分阶段逐步到位,实施定居区水务一体化管理,发挥项目的规模效应;定居区规模要做到“水土平衡、供需平衡”,防止“小马拉大车”;工程建成后,要加强水文监测,为水库安全度汛和调度提供可靠的基础依据.定居兴牧水源工程的顺利实施,赋予了“新疆效率”深刻的科学内涵,对于加速现代草原生态畜牧业发展,具有一定的借鉴、指导作用.  相似文献   

12.
中国高度城市化区域水源地环境安全问题较突出,同时环境安全管理技术手段落后,无法满足管理需求。为了解决这一问题,文章以深圳某水库为例探讨了高度城市化区域水库水源地环境安全管理信息系统的功能需求和开发方案,并基于GIS技术开发了具有多种功能的城区水库水源地环境安全管理信息系统。经实际应用,识别出深圳某水库水源地主要风险源为库尾截污闸、沙湾路水库段、大望桥段、丹沙路桥段;水源地敏感带除在一级水源保护区内有分布外,主要是分布在二级水源保护区内,甚至在距水库较远的二级水源保护区内的一些区域也被识别为敏感地带,该系统可弥补饮用水水源保护区划分方法的不足,用于辅助水源保护区的监管决策;主要风险源发生污染事故时,污染物最快约20 h可到达坝前取水口处;利用实测小时降雨量实现了库尾截污闸处洪峰和开闸泄洪过程,以及泄洪污染物在水库中的迁移扩散过程预报;通过现场视频监控和水质在线监测实现了水源地环境的实时监控。应用结果表明,该系统实用性强,可为高度城市化区域水库水源地环境安全管理提供有效的决策支持。  相似文献   

13.
Water conservation, distribution and management are highly contested in the Hunter Valley of New South Wales. During the height of the Millennium drought calls from local politicians and community leaders alike suggested that there was a need to ‘drought-proof’ not only the Hunter region but also the Australian continent from recurring climatic events. In response to this, Hunter Water Corporation framed its long-term sustainable water policies around the proposed development of ‘Tillegra Dam’ as a means to ensure future water security for the region. Local residents, centred around the ‘No Tillegra Dam Group’, opposed the dam, pointing to its harmful effects and more sustainable demand-side options. Scientific studies also indicated that future droughts were unlikely to place stress on current water levels, thereby making the dam unnecessary. Hunter Water, however, co-opted the notion of ‘drought-proofing’ to argue for the continuation of large-scale infrastructure projects rather than pursue less costly, more sustainable options. As a result, arguments and discourses over the dam's construction became increasingly complex, involving environmental, economic and ethical issues that ultimately favoured local community perspectives. This paper examines how the different stakeholder arguments were framed and considers the important role that communities can play in altering decision making.  相似文献   

14.
小流域综合管理信息系统集成研究   总被引:14,自引:2,他引:14  
本文介绍的小流域管理与决策支持信息系统 ,是以小流域综合治理与科学决策为目标 ,以地块为基本操作单元的土壤侵蚀模型、生产潜力模型、成本效益模型与GIS的集成系统。该系统具有数据管理、查询、更新、处理、模型分析和输出等多种功能。分析模型与GIS集成的基本单元是地块 (landunit) ,在地块上实现模型参数的提取与传递、模型计算及显示与分析。在分析各种集成方式的基础上 ,选取了动态连接库及其扩展方式 ,实现了土壤侵蚀模型、生产潜力模型、成本效益模型、规划模块与GIS的紧密集成 ,以统一的图形用户界面 ,服务于水土保持的现代化管理和小流域综合治理  相似文献   

15.
我国北方地下水危机与可持续农业的发展   总被引:4,自引:2,他引:4  
章光新  邓伟  何岩 《干旱区地理》2004,27(3):437-441
我国北方地区大约70%的地下水资源开采量用来灌溉农业。超采地下水资源,带来了一系列生态环境地质问题,如区域地下水位下降、地面沉降、海水入侵、土地盐渍化和荒漠化等。针对上述问题,提出四大战略性对策与措施:(1)发展节水型农业,持续高效利用水资源;(2)南水北调和区域管理是解决北方地下水危机的重要途径;(3)保护水资源和水环境,增加水资源可利用量;(4)开展变化环境下的水循环与水量平衡研究,综合开发利用水资源。来解决北方地区地下水资源危机,保证可持续农业的发展,促进我国社会经济稳定健康发展。  相似文献   

16.
Rural communities worldwide are increasingly confronted with the simultaneous impacts of environmental change dynamics and processes of economic restructuring that diminish traditional sources of state support while shifting investments toward large-scale intensive production models. A key question in this context is how livelihoods are affected by these interacting forces of change and whether new production models can contribute to resilience at the household and community scales. Here we examine the impacts of oil palm production on marginal rural communities in Mexico that have experienced both the economic changes associated with neoliberal policy reforms and the dynamics of environmental change. We find that oil palm production can contribute to livelihood resilience when community members participate in its management and governance and when production is associated with state support, but that the kinds of neoliberal policies promoting oil palm expansion may exacerbate existing community vulnerabilities in the face of environmental change.  相似文献   

17.
Ba  Wulong  Du  Pengfei  Liu  Tie  Bao  Anming  Chen  Xi  Liu  Jiao  Qin  Chengxin 《地理学报(英文版)》2020,30(1):164-176

In the context of climate change and over-exploitation of water resources, water shortage and water pollution in arid regions have become major constraints to local sustainable development. In this study, we established a Soil and Water Assessment Tool (SWAT) model for simulating non-point source (NPS) pollution in the irrigation area of the lower reaches of the Kaidu River Basin, based on spatial and attribute data (2010–2014). Four climate change scenarios (2040–2044) and two agricultural management scenarios were input into the SWAT model to quantify the effects of climate change and agricultural management on solvents and solutes of pollutants in the study area. The simulation results show that compared to the reference period (2010–2014), with a decline in streamflow from the Kaidu River, the average annual irrigation water consumption is expected to decrease by 3.84x108 m3 or 8.87% during the period of 2040–2044. Meanwhile, the average annual total nitrogen (TN) and total phosphorus (TP) in agricultural drainage canals will also increase by 10.50% and 30.06%, respectively. Through the implementation of agricultural management measures, the TN and TP in farmland drainage can be reduced by 14.49% and 16.03%, respectively, reaching 661.56 t and 12.99 t, accordingly, and the increasing water efficiency can save irrigation water consumption by 4.41 x108 m3 or 4.77%. The results indicate that although the water environment in the irrigation area in the lower reaches of the Kaidu River Basin is deteriorating, the situation can be improved by implementing appropriate agricultural production methods. The quantitative analysis results of NPS pollutants in the irrigation area under different scenarios provide a scientific basis for water environmental management in the Kaidu River Basin.

  相似文献   

18.
区域水资源与经济社会耦合系统可持续发展的量化分析   总被引:4,自引:0,他引:4  
关伟 《地理研究》2007,26(4):685-692
通过对水资源-生态环境-经济社会耦合系统互动关系的分析和对该耦合系统可持续发展模式的探讨,利用模糊优选模型将多个评价指标转化为单一指标,采用模糊隶属度描述可持续度来衡量复杂水资源系统可持续发展水平的评价方法,并结合辽宁省水资源开发与利用的实际情况,研究区域水资源可持续利用与经济社会协调发展的关系。研究结果表明,目前辽宁水资源系统可持续发展水平相对较低(全省水资源系统的可持续度仅为0.2456),尚有较大的开发潜力和提升空间。研究成果可为辽宁省水资源可持续利用及其管理提供定量的决策依据。  相似文献   

19.
This paper outlines pressures on agricultural land in periurban Kumasi, Ghana. A survey of agricultural practices underlines the recent and rapid transition from agricultural to urban land use in the periurban interface, and shows how farmers are reacting by reducing fallow periods. Farmers are also intensifying agriculture near streams and rivers through increased use of irrigation, in response to growing urban markets for a wider range of vegetables. We identify specific problems of water resource pollution and waste management, with particular reference to farmland irrigation. We report results of composting interventions as a community‐based waste management strategy. We consider integrated organic waste recycling as a generic strategy to help protect periurban natural resources, to enhance food production through nutrient recycling, and to improve community sanitation.  相似文献   

20.
The optimal spatial allocation of irrigation water under uncertainty has become a serious concern because of irrigation water shortage and uncertain factors that affect irrigation water allocation. In this study, an optimal multi-objective model for irrigation water allocation under uncertainty is developed to maximise the economic benefit of crops and minimise the operation cost and water deficit of crop irrigation. The original and optimal plantation structure, irrigation mode and soil water content are acquired through geospatial technology. A bilayer nested optimisation (BLNO) algorithm is designed to produce multiple individuals of design vectors using an ant colony neural network algorithm for an outer optimisation. Meanwhile, a continuous adaptive ant colony (CAAC) algorithm is used for inner optimisation to calculate the interval values of the uncertain model. The crop distribution and irrigation mode are obtained to parameterise the planting area and the water demand of each crop and each block in the multi-objective model. This model is then solved and analysed. Compared to the optimal schemes obtained from an inexact two-stage fuzzy-stochastic programming and the CAAC, respectively, BLNO can effectively and efficiently solve the optimal spatial allocation of irrigation water under uncertainty. This method can spatially maximise the economic benefit of crops and minimise the operation cost and water deficit of crop irrigation using lower and upper bound maps whilst visually obtaining the exact crop type, reasonable irrigation method and precise water demand for each block and for the entire irrigated area.  相似文献   

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