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1.
陕北干旱半干旱地区雨水集蓄与高效利用技术的分析   总被引:2,自引:1,他引:1  
干旱的山坡地雨水资源潜力巨大,雨水的集蓄与高效利用为解决干旱缺水与水土保持找到一个结合点,分析了降雨特点,总结了雨水利用的发展过程,提出了雨水及径流资源利用的主要形式(1)蓄水保墒技术.蓄水技术主要有水土保持耕作法,以及改良土壤,增强土壤持水能力.保墒技术有覆盖(秸秆覆盖、地膜覆盖)保墒,耕作保墒技术.(2)雨水叠加利用技术.主要有鱼鳞坑以及径流林业等形式,集水技术在空间上对降水起到了有效的再分配作用.(3)雨水聚集利用技术.在山坡地径流汇集处兴修"旱井",把降水富集并存储起来,使自然降水变成时空可调的现实水资源.(4)雨水在聚集条件下高效利用技术.在雨水聚集利用技术的基础上,利用地形落差,实施自压滴灌或渗灌,使降水与植物需水错位可得到改善和缓解.最后,提出了雨水聚集和高效利用需要研究解决的关键技术.  相似文献   

2.
国内外雨水资源利用研究综述   总被引:65,自引:5,他引:60  
干旱是一个长期存在的世界性难题。我国是一个干旱半干旱面积很大的国家,干旱严重地制约着农业的可持续发展。而雨水资源的利用是解决或缓解干旱的重要途径。围绕雨水资源的利用,人们做了许多创造性的理论探索和技术研究,研究出许多雨水资源利用的方式,归纳起来主要有3个方面;就地拦蓄利用,覆盖抑制蒸发利用和雨水富集叠加利用。针对这3个方面,对国内外雨水资源利用现状进行了总结,提出了雨水资源利用存在的问题。  相似文献   

3.
基于GIS的区域雨水资源化潜力评价模型研究   总被引:6,自引:1,他引:5  
区域雨水资源化潜力的定量评价对于雨水资源开发利用的宏观决策、规划设计具有十分重要的意义。该文以黄土高原地区为例,系统分析了影响区域雨水资源化潜力的各个因子,确定定量评价区域雨水资源化潜力的各项指标,并运用GIS技术,集成多种来源、多种比例尺和多种类型的数据,建立区域雨水资源化潜力定量评价模型。评价模型对于黄土高原地区雨水资源可持续利用及生态与环境保护具有重要作用。  相似文献   

4.
利用土壤层净化雨水补给地下水的试验研究   总被引:8,自引:0,他引:8  
姜凌  秦耀民 《水土保持学报》2005,19(6):94-96,105
利用城市雨水资源补给地下水,不仅可以控制城市非点源污染,还能补充日益匮乏的地下水资源。但对雨水中污染物的控制,是利用雨水人工补给地下水技术中最棘手的问题。针对这一问题,提出利用人工土壤层处理雨水径流的方案,研究了雨水在土壤层中的净化规律,得出土砂比参数为5:1;渗透厚度为1m的人工土壤层能去除雨水径流中大部分污染物(COD),对雨水径流中的微量污染物N,P和重金属等也具有显著的去除效果。  相似文献   

5.
雨水资源集蓄利用研究进展   总被引:1,自引:0,他引:1  
水资源危机已成为全球性的问题,如何高效利用有限的水资源,特别是雨水资源,提高雨水资源的利用率,已被世界各国所关注。在详细阐述雨水集蓄利用的发展历史、概念和理论的基础上;对国内外雨水资源的集蓄技术和高效利用技术及其应用研究进行了系统分析和总结;同时,提出了目前雨水集蓄利用研究发展趋势。  相似文献   

6.
黄土高原水土保持与雨水资源化   总被引:3,自引:0,他引:3       下载免费PDF全文
在分析黄土高原水土保持工作难度的基础上,进一步研究区域水土保持的科学内涵,以及水土保持与雨水资源化的关系。认为:黄土高原水土保持的关键与核心在于如何实现雨水资源化;降雨径流调控与利用不仅可实现雨水资源化,而且可以同步解决制约该区发展的干旱缺水与水土流失并存2大难题。在此基础上,提出了黄土高原水土保持亟待研究的科学问题与技术问题,并初步构建了黄土高原水土保持与雨水资源化的技术体系框架。  相似文献   

7.
60年代,我国曾掀起过旱井集蓄利用雨水的热潮,时隔30余年的今天,这一热潮再度兴起,其原因何在?本文从利用雨水资源的必要性、现实可能性、实践效果等三个方面进行了分析论证,结果表明:我国现阶段开发利用雨水资源前景十分广阔。  相似文献   

8.
辽西北旱农区的气候特点与土壤墒情调控   总被引:1,自引:0,他引:1       下载免费PDF全文
辽宁省西北部地区多年降雨量与蒸发量频率分析结果表明,春季抗旱保苗是这一地区发展旱地农业的技术关键。该区湿润系数的经验频率以夏季最高,秋季为85.71%。由于这一地区水资源短缺,发展灌溉困难,这不仅使春季保墒成为必需,也使跨季节调控土壤墒情成为可能。采取的夏深松-蓄集雨水,秋整地-施肥与覆膜保墒,翌年春季适时播种措施,改革栽培与耕作方式,春季保苗效果十分明显,减少了土壤水分的无效蒸发,有效地利用雨水资源,为该区作物高产和农业高效奠定了基础。  相似文献   

9.
雨水利用与水土保持和农业持续发展   总被引:20,自引:1,他引:19       下载免费PDF全文
雨水资源是西北黄土高原旱作区农田生产的主要水源。该区域年均雨水总量2757亿m^3,是当前前年地表水和地下水用量的9.2倍。因降水时空分布不均,“易失多变”,水土流失和干旱问题严重,卫水利用率40%左右,作物水分利用效率仅3.0-4.5kg(hm^2.mm)。人工收集与调配利用雨水,是水土保持和农业生产的一个结合点,可使降寸桑加增效,人工收集利用雨水在西北历史悠久,有坝、塘、池、井、窖和卫坡梯田等  相似文献   

10.
小流域雨水资源化潜力及其可持续利用分析   总被引:9,自引:2,他引:7  
针对黄土高原地区水资源严重短缺的态势和生态环境建设的需要,基于可持续发展理念,以小流域作为研究单元,以雨水资源作为研究对象,提出小流域雨水资源化潜力的概念,分析不同层次的小流域雨水资源化潜力,探讨雨水资源可持续性与可持续利用的关系,建立了小流域雨水资源不同利用类型的判别模式,为黄土高原雨水资源的持续高效利用和流域生态环境健康发展提供理论依据。  相似文献   

11.
Soil water conservation is critical to long-term crop production in dryland cropping areas in Northeast Australia. Many field studies have shown the benefits of controlled traffic and zero tillage in terms of runoff and soil erosion reduction, soil moisture retention and crop yield improvement. However, there is lack of understanding of the long-term effect of the combination of controlled traffic and zero tillage practices, as compared with other tillage and traffic management practices.In this study, a modeling approach was used to estimate the long-term effect of tillage, traffic, crop rotation and type, and soil management practices in a heavy clay soil. The PERFECT soil–crop simulation model was calibrated with data from a 5-year field experiment in Northeast Australia in terms of runoff, available soil water and crop yield; the procedure and outcomes of this calibration were given in a previous contribution. Three cropping systems with different tillage and traffic treatments were simulated with the model over a 44-year-period using archived weather data.Results showed higher runoff, and lower soil moisture and crop production with conventional tillage and accompanying field traffic than with controlled traffic and zero tillage. The effect of traffic is greater than the effect of tillage over the long-term. The best traffic, tillage and crop management system was controlled traffic zero tillage in a high crop intensity rotation, and the worst was conventional traffic and stubble mulch with continuous wheat. Increased water infiltration and reduced runoff under controlled traffic resulted in more available soil water and higher crop yield under opportunity cropping systems.  相似文献   

12.
Intensive glyphosate use has contributed to the evolution and occurrence of glyphosate-resistant weeds that threaten production of many crops. Sustained use of this highly valued herbicide requires rotation and/or substitution of herbicides with different modes of action. Cotton growers have shown considerable interest in the protoporphyrinogen oxidase inhibitor, fomesafen. Following registration for cotton in 2008, use has increased rapidly. Environmental fate data in major use areas are needed to appropriately evaluate risks. Field-based rainfall simulation was used to evaluate fomesafen runoff potential with and without irrigation incorporation in a conventional tillage system (CT) and when conservation tillage (CsT) was practiced with and without cover crop residue rolling. Without irrigation incorporation, relatively high runoff, about 5% of applied, was measured from the CT system, indicating that this compound may present a runoff risk. Runoff was reduced by >50% when the herbicide was irrigation incorporated after application or when used with a CsT system. Data indicate that these practices should be implemented whenever possible to reduce fomesafen runoff risk. Results also raised concerns about leaching and potential groundwater contamination and crop injury due to rapid washoff from cover crop residues in CsT systems. Further work is needed to address these concerns.  相似文献   

13.
黄土高原生物利用型土壤干层的水文生态效应研究   总被引:25,自引:0,他引:25  
对黄土高原高产农、林、草、灌、果5种植被1000cm土层土壤剖面含水量多点测定结果表明,各植被类型均存在不同程度的生物利用型土壤干层,该土壤干层的水文作用表现为增强土壤-植被-大气间垂直水分交换,阻碍入渗降雨转化为地下径流,削弱植被对枯水季节低径流量的补偿能力,其生态效应是恶化植物生长的土壤水分环境,削弱土壤水库对年际干旱的调节能力。  相似文献   

14.
Agricultural production systems are complex involving variability in climate, soil, crop, tillage management and interactions between these components. The traditional experimental approach has played an important role in studying crop production systems, but isolation of these factors in experimental studies is difficult and time consuming. Computer simulation models are useful in exploring these interactions and provide a valuable tool to test and further our understanding of the behavior of soil–crop systems without repeating experimentation.Productivity erosion and runoff functions to evaluate conservation techniques (PERFECT) is one of the soil–crop models that integrate the dynamics of soil, tillage and crop processes at a daily resolution. This study had two major objectives. The first was to calibrate the use of the PERFECT soil–crop simulation model to simulate soil and crop responses to changes of traffic and tillage management. The second was to explore the interactions between traffic, tillage, soil and crop, and provide insight to the long-term effects of improved soil management and crop rotation options. This contribution covers only the first objective, and the second will be covered in a subsequent contribution.Data were obtained from field experiments on a vertisol in Southeast Queensland, Australia which had controlled traffic and tillage treatments for the previous 5 years. Input data for the simulation model included daily weather, runoff, plant available water capacity, and soil hydraulic properties, cropping systems, and traffic and tillage management. After model calibration, predicted and measured total runoffs for the 5-year period were similar. Values of root mean square error (RMSE) for daily runoff ranged from 5.7 to 9.2 mm, which were similar to those reported in literature. The model explained 75–95% of variations of daily, monthly and annual runoff, 70–84% of the variation in total available soil water, and 85% of the variation in yield. The results showed that the PERFECT daily soil–crop simulation model could be used to generate meaningful predictions of the interactions between crop, soil and water under different tillage and traffic systems.Ranking of management systems in order of decreasing merit for runoff, available soil water and crop yield was (1) controlled traffic zero tillage, (2) controlled traffic stubble mulch, (3) wheeled zero tillage, and (4) wheeled stubble mulch.  相似文献   

15.
斥水土壤中的水热运动规律与数值模型   总被引:7,自引:2,他引:5  
斥水土壤很难被雨水湿润,影响种子发芽出苗而造成农业减产。由于地表干燥而引起风蚀水蚀,造成土地退化。这一问题在澳大利亚、荷兰、新西兰与美国引起重视。斥水土壤中水分分布往往是无规律的“指状”,到目前为止,没有成功的数学模型。作者从研究斥水土壤地区的耕作工程实践出发,采用沟种之后,水分的分布就有了规律性。开沟播种时,耕作机械把表层斥水性特别强的土壤推到垄上而形成几乎不透水的垄,下雨时雨水只能从沟中渗入形  相似文献   

16.
滇中地区小流域治理前后水土流失变化规律的研究   总被引:9,自引:1,他引:8  
通过生物措施、工程措施和耕作措施对滇中地区典型小流域—王家箐进行综合治理,观测了治理前后气象、水文、土壤侵蚀资料,分析了治理前后试验区降雨与径流、侵蚀之间的关系及变化。结果表明,试验区的水土流失主要集中在5~10月,区内次降雨的径流量、侵蚀量与降雨量和最大30 min雨强乘积的相关性最好,其关系式为一元三次方函数,相关系数在0.956到0.993之间(极显著相关);月径流量、月侵蚀量与月降雨量之间的关系为一元幂函数,相关系数在0.819到0.985之间(极显著相关)。采取生物措施、工程措施和耕作措施相结合的综合治理方式,能有效抑制以坡耕地为主的小流域的水土流失,但不改变流域降雨径流侵蚀函数关系式,只改变其系数。  相似文献   

17.
Crops are the most important ground cover on slope farmland and have a significant impact on the soil erosion. But soil erosion on slope farmland is also affected by many other factors, such as topography and rainfall. In order to explore the effect of crop growth on soil erosion on different slope gradient of slope farmland, and analyze the interaction of crop growth and slope gradient on soil erosion, this study used artificial simulated rainfall to observe the runoff rates and soil loss amounts under different slope gradients for maize, soybeans, and winter wheat in different growth stages. Results showed that crops and slope gradient both significantly affected production and development of slope runoff. Compared with bare land, mean runoff rate on slopes was reduced by 24%, 32%, and 94% respectively, and sediment yield was decreased by 44%, 55%, and 99% respectively on maize, soybean, and winter wheat fields. Inhibitory effects of crops on slope runoff rate and sediment yield were enhanced with crop growth and decreased with increasing slope gradient. Crop growth and coverage could offset the impact of increasing slope gradient on runoff and sediment to some extent and reduced water and soil loss on slopes. Sediment yield was produced largely when the slope gradient was greater than 10 degrees on maize and soybean fields, but soil erosion was effectively inhibited when the slope gradient was less than 15 degrees on winter wheat fields. Crop planting can effectively reduce the impact of slope gradient on soil erosion, especially during the flourishing period of crop growth.  相似文献   

18.
Increase in alfalfa (Medicago sativa L.) production for energy (gasification of stems) and protein supplement (from leaves) has been proposed for the upper Midwestern United States, an area where corn (Zea mays L.) in rotation with soybean (Glycine max L.) is the predominant crop sequence. This study was undertaken to assess the impact on runoff and water quality, especially for the loss of oxygen demanding material with snowmelt. Four field size watersheds were instrumented at Morris, Minnesota, USA on a rolling prairie landscape. Snowmelt runoff from each watershed was measured with two flumes with overlapping ranges arranged in series. An automatic water sampler collected runoff samples for chemical analysis. Oxygen demand was used as a surrogate for reduced carbon. Water samples were analyzed for total solids, biochemical oxygen demand (BOD), and chemical oxygen demand (COD). Based on the results of snowmelt events of 1997, 1998, and 1999, the alfalfa fields yielded more runoff than corn-soybean fields. The loss of total solids was more consistent from alfalfa fields. Total solids losses interacted with crop and year. Compared to alfalfa fields losses were less following soybeans and greater following corn. On average losses were similar between alfalfa and corn-soybean fields. Runoff from alfalfa fields contained about four times more BOD than corn-soybean fields. Although not statistically significant due to only two replications, there was a similar trend for COD. This study shows that although losses of total solids in snowmelt from alfalfa fields was similar to corn-soybean fields, there can be increased losses of oxygen demanding materials.  相似文献   

19.
Conservation management decreases surface runoff and soil erosion   总被引:1,自引:1,他引:0  
Conservation management practices – including agroforestry, cover cropping, no-till, reduced tillage, and residue return – have been applied for decades to control surface runoff and soil erosion, yet results have not been integrated and evaluated across cropping systems. In this study we collected data comparing agricultural production with and without conservation management strategies. We used a bootstrap resampling analysis to explore interactions between practice type, soil texture, surface runoff, and soil erosion. We then used a correlation analysis to relate changes in surface runoff and soil erosion to 13 other soil health and agronomic indicators, including soil organic carbon, soil aggregation, infiltration, porosity, subsurface leaching, and cash crop yield. Across all conservation management practices, surface runoff and erosion had respective mean decreases of 67% and 80% compared with controls. Use of cover cropping provided the largest decreases in erosion and surface runoff, thus emphasizing the importance of maintaining continuous vegetative cover on soils. Coarse- and medium-textured soils had greater decreases in both erosion and runoff than fine-textured soils. Changes in surface runoff and soil erosion under conservation management were highly correlated with soil organic carbon, aggregation, porosity, infiltration, leaching, and yield, showing that conservation practices help drive important interactions between these different facets of soil health. This study offers the first large-scale comparison of how different conservation agriculture practices reduce surface runoff and soil erosion, and at the same time provides new insight into how these interactions influence the improvement or loss of soil health.  相似文献   

20.
In Tigray (Northern Ethiopia), soil moisture has been identified as the most limiting factor in agricultural production; on the other hand, loss of rain water through runoff as well as the induced soil loss has been determined as a critical problem in the region in the last two to three decades. To alleviate the above paradox, the government has mobilized communities and resources for the construction of physical soil and water conservation structures (stone bunds, terraces) in almost all land uses. However, yield improvement was mainly concentrated within the vicinity of the structures and runoff continued to overtop the structures, as no measures for in situ soil conservation were taken. The terwah system, consisting of traditional ploughing followed by making every 1.5–2 m contour furrows, and permanent raised beds with contour furrows at 60–70 cm interval treatments, were considered and evaluated as practices that could increase the efficiency of in situ water utilization and soil conservation. An experiment was started in Gum Selasa, which is one of the drought prone areas in Tigray, whereby runoff volume and sediment load were measured after every rain event. Permanent raised beds with contour furrows at 60–70 cm interval significantly (P < 0.05) reduced runoff volume, runoff coefficient and soil loss as compared to traditional ploughing: 255, 381 and 653 m3 ha−1 runoff was recorded from permanent bed, terwah and traditional ploughing, respectively during the whole cropping season. The above runoff induced 4.7 t ha−1 soil loss from permanent bed, 7.6 t ha−1 from terwah and 19.5 t ha−1 from traditional ploughing. Overall, contour furrows and permanent raised beds can be part of the ongoing intensification process which includes physical soil and water conservation, slope reforestation, irrigation development and agro forestry in crop lands. Moreover, the use of permanent raised beds if combined with crop mulching and crop diversification is an important component for the development of sustainable conservation agriculture practices in the region.  相似文献   

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