共查询到20条相似文献,搜索用时 15 毫秒
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Omar K.M. Ouda 《国际水资源开发杂志》2014,30(2):282-292
Saudi Arabia's groundwater resources have been heavily over-exploited to achieve food self-sufficiency. The country enacted a new agricultural policy that discourages the cultivation of wheat and encourages that of vegetables and fruits. This has produced significant reductions in irrigation water demand as well as food self-sufficiency. This paper reviews the performance of the Saudi agricultural sector and presents four scenarios forecasting the new policy's long-term impacts on the use of water for agriculture. The findings show that the new policy does not support sustainable utilization of groundwater resources. Additional policy modifications are needed to optimize the combination of import and domestic production of agricultural products based on a sustainable water utilization strategy. 相似文献
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Omar K. M. Ouda 《国际水资源开发杂志》2016,32(5):799-809
The Kingdom of Saudi Arabia considers treated wastewater a major water source and aims to achieve 100% use of treated wastewater by 2025. This article reviews Saudi Arabia’s treated wastewater utilization status to date. It also highlights the key challenges facing the authorities, such as the substantial growth in demand for wastewater services; low coverage of the existing wastewater collection, treatment, and treated wastewater use systems; and the capital investment needed for infrastructure development. Finally, the article highlights the initiatives taken thus far to tackle these challenges and recommends further initiatives towards successful achievement of Saudi Arabia’s treated wastewater utilization objective. 相似文献
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Omar K.M. Ouda 《国际水资源开发杂志》2014,30(2):335-344
Saudi Arabia is facing a chronic water-shortage problem. Demand far exceeds the sustainable yield of both conventional and non-conventional water resources. The resulting demand–supply gap is being bridged through groundwater depletion. In this paper, demand–supply gaps for the coming 20 years are projected under three scenarios: optimistic, moderate and pessimistic. Future sustainable water yields are calculated and allocated to projected water demand in the domestic, industrial and agricultural sectors. The study shows that Saudi Arabia will not be able to bridge the demand–supply gap in the near future. Intensive water demand management measures are needed in all sectors to minimize future demand–supply gaps, especially focused on the largest water consumer: the agricultural sector. 相似文献
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从运城市的基本情况出发,根据灌区内水资源状况,提出了引用客水置换地下水的发展战略;结合运城市灌区的实际和发展规划,认为灌区农业灌溉节水的潜力巨大,必须加大工程和管理节水力度,探索灌区农业节水新途径。 相似文献
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在直接引用水库底层水进行灌溉的地区,水温偏低已成为影响效益农业高质高产的关键制约因素。而新型的悬浮式适温水取用装置及高效的优灌系统技术模型基本解决了这一难题,并初现成效。 相似文献
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Arid lands are in the need of additional water supply but water transportation from outside of the natural hydrological cycle
causes the groundwater to rise within the urban areas. Additional water supply from surrounding areas or through the desalination
plants provides comfort in domestic activities but after the usage, its disposition is necessary in an efficient manner. Unfortunately,
arid region cities have neither sufficient nor efficient sewage system. Consequently, the water returned to surface cesspools
and leakages from insufficient sewage system makes internal groundwater recharge within the urban area. Additionally, water
supply system leakages further raise the groundwater level. Deterioration in water quality becomes a potential danger for
the infrastructure and foundations. Surface depressions in the city may be flooded due to groundwater level rise and at times
bed smells occur at various parts of the city.
In this paper, a quantitative method is followed to assess groundwater level rise risks in addition to the few chemical risks
associated with sulfate and chloride solids. It is observed that each one of these variables has different probability distribution
function and expose risk maps with different features. 相似文献
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针对天镇县水资源匮乏、农业灌溉水利用率低的现状,结合实地地质条件,较为系统地阐述了农业节水所存在的问题以及相应的解决措施。在此基础上,提出了合理建设蓄洪水库、引入先进灌溉技术以及积雪溶化灌溉等改进方案,能最大限度补偿农业缺水所带来的损失,提高水资源利用率。 相似文献
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渗灌条件下水稻的节水灌溉制度和氮肥运筹技术研究 总被引:2,自引:1,他引:2
针对江苏省淮北平原地区稻麦轮作生产实际,在田间埋设塑料波纹暗管,通过调节外沟水位对水稻实施渗灌,就渗灌条件下水稻的节水灌溉制度和氮肥运筹技术进行了研究。提出了渗灌条件下以稻田地下水位和土壤含水量作为控制指标的水稻节水灌溉模式,该技术和常规浅水勤灌相比,水稻节水达16.5%,增产14.3%。试验结果还表明,水稻采用节水灌溉制度后,氮肥用量和基蘖肥与穗粒肥的比例显著影响水稻地上部分干物质积累、矿质营养、籽粒产量和营养品质,渗灌条件下水稻高产优质、浅层地下水不受NO3-N污染的施N量为270~315kgN/hm2,基蘖肥/穗粒肥为5∶5。 相似文献
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本文对一块66m×100m的雨养麦田连续5个麦季的试验资料分析表明,其雨养麦田产量为3450-5625kg/hm2。根据本区雨养麦田历年水分条件的分布特征,可推定这个产量幅度的出现概率为74.8%。对5个试验麦季的耗水过程进行了分析,得出一条麦田理想的土壤湿度动态曲线,据此提出一个节水灌溉模型.它首先根据麦播期的土壤 有效储水量(Se)和降雨量(R)预报预计灌溉定额,并进行预分配,然后在应用过程 中对灌溉程序进行修正,使其湿度与理想的土壤湿度偏差不超过±50mm。这个模型可比现行的传统灌溉模式节省灌溉用水18%。 相似文献
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气候变暖不仅影响水资源量及其时空分布的变化,而且也会使农作物蒸发蒸腾量增加,从而加剧农业水资源供需矛盾。因此,研究气候变化对农业需水量的影响对保障农业用水安全具有重要的意义。本文利用陕西省宝鸡峡灌区11个气象站28 a的气象资料,分析了灌区气候变化特征;计算了主要作物需水量和农田灌溉需水量;利用单因素敏感性分析法研究了气候变化对农业需水量的影响。研究结果表明:灌区年平均气温显著上升,降水量持续下降,蒸发量明显增大,大部分地区相对湿度和风速显著下降,而日照时数有所增加;冬小麦、玉米、棉花和油菜生育期需水量明显增加;各气候因素对农田灌溉需水量影响顺序为:降水量>相对湿度>最高气温>日照时数>平均气温>风速,气温的上升、相对湿度的下降、降水量的减少以及日照时数的增大使作物需水量明显增大,而灌溉面积减小使农业需水量有减少的趋势。 相似文献
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宁夏引黄灌区是重要的粮食生产基地,其农业耗水占据了绝大部分引黄耗水量。本文在以引黄水量为主要灌溉水源、适量采用开采地下水作为补充的基础上,对整个灌区采用地表水与地下水联合灌溉的节水效益进行了定量研究。结果表明,采用井渠双灌现状年引黄灌区十县市可减少渠首引水量1.53×108m3,减少损失水量将达到0.68×108m3。对2010年的预测结果表明,可减少田间引黄灌溉用水量1.95×108m3,减少渠首引黄水量为3.48×108m3,减少输水过程中的损失水量为1.54×108m3,具有显著的节水效益。 相似文献
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Jadwiga R. Ziolkowska 《国际水资源开发杂志》2018,34(6):944-960
ABSTRACTThis article evaluates profitability of irrigated versus non-irrigated agricultural production of major crops (corn, cotton, wheat, soybeans, sorghum) in 2010 (a wet year) and 2011 (an exceptional drought year) in Oklahoma and Texas. It also estimates the economic value of water for agricultural production in both states to answer the question of added value generated with irrigation. Answering those questions is critical in the face of exceptional and severe droughts affecting Oklahoma and Texas in the past decade, in addition to steeply declining groundwater resources in the Ogalalla Aquifer. The results can help with designing mitigation and adaptation measures to water scarcity. 相似文献
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农业高效用水研究进展与成果回顾 总被引:3,自引:0,他引:3
在系统阐述农业高效用水研究进展与发展趋势基础上,对农业高效用水研究领域取得的主要成果及创新进行回顾和综述。在应用基础与前沿技术方面,开展农田水土管理、灌区节水决策、精量灌溉预报决策、精量控制地面灌溉、喷微灌水肥高效利用、农田氮素迁移转化与控制等方法和技术研究;在关键技术与产品方面,对喷滴灌、地面灌、管道输水灌溉、灌区用水管理、农田排水与涝渍灾害防治、劣质水资源化灌溉利用、农业水资源开发利用、节水灌溉设备质量监测与评价等技术和产品进行研发;在宏观战略与发展对策方面,开展农村水利发展战略、粮食安全与灌溉发展战略、节水灌溉发展战略和农村水利科技发展战略等研究。通过国家重大科技成果推广应用项目,对取得的科技成果进行转化和推广应用,为我国农业高效用水提供了新技术、新方法和新产品。 相似文献