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1.
The continuous high demand of water resources for agricultural uses in Jordan is leading to a water crisis. A possible partial solution may be to import food which requires large amounts of water to grow instead of cultivating high water consuming crops. Crops such as banana and citrus cause a huge virtual water loss, which can be reduced by cultivating other less water-demanding crops. This paper focuses on analyzing the economic value of cultivating tree fruit from a virtual water perspective. The virtual water calculations in this study depend on the average rainfall, water quota, and the crops’ water requirements (CWR). The gross profit to the water use ratio showed that banana has the lowest value 0.085 JD/m3, while lemon has the highest value 1.65 JD/m3. The calculations show that the average embedded water in fruits varies from about 470 m3/ton for grapes to about 2,500 m3/ton for dates. Banana and citrus plantations consume about 21 and 71 million cubic meters (MCM) annually, respectively, which represent about 85% of the total water consumption in fruit tree plantation. The virtual water flow estimation embedded in fruits shows that Jordan imports about 77 MCM per year. However it exports about 29 MCM per year. The results were analyzed from an integrated water resources management (IWRM) perspective. The analysis shows that a way to recover some of the water costs involved in, e.g., banana production would be to increase the fertilizer cost by about 10%. This would double the water cost and increase the banana production cost by about 6.8%. Using this alternative could be a way to better manage the huge losses in virtual water involved in banana production in the Jordan Valley.  相似文献   

2.
This study quantifies and maps the water footprint of Kenya from both production and consumption perspectives and estimates the country’s virtual water export and import. Kenya’s virtual water export related to trade in agricultural products was 4.1 km3/y; its virtual water import was 4.0 km3/y. The average export earning per unit of water consumed or polluted in producing agricultural export products was USD 0.25/m3, while the average expenditure on imported commodities per unit of virtual water imported was USD 0.10/m3. In addition to increasing water productivity in crop production, Kenya can mitigate its water scarcity by increasing imports of water-intensive products such as cereals and exports of high-value products such as cut flowers, vegetables, spices and tea.  相似文献   

3.
水会计恒等式是在水会计核算中反映各要素之间内在联系的恒等式,是水会计科目与账户设置和水资产负债表编制的重要理论依据。在权责发生制的基础上,对水会计恒等式各要素进行探讨,阐述了各要素的基本概念、确认条件、组成部分及计算方法。在此基础上,以滨海新区为例建立了滨海新区水会计核算体系。通过对近年水资产结构、水负债结构和水主体权益结构进行分析与评价,结果表明:2018年滨海新区水资产总量为68106×104m~3,较2017年增加了1. 29%,较2016年减少了2. 05%;水负债总量为7. 60×104m~3,较2017年减少了51. 90%,较2016年减少了75. 08%;水主体权益总量为68098. 40×10~4m~3,较2017年增加了1. 30%,较2016年减少了2. 01%;水资产负债率为0. 01%,较2017年减少0. 01%,较2016年减少0. 03%。体现2018年滨海新区水资源优化配置程度较高、涉水生产活动稳健、负债量小、水主体权益程度化较高等水资源管理特点。  相似文献   

4.
Most studies in the field of virtual water trade concentrate either on the global, national or sub-national level, or on the water footprint of individual products. This article assesses the virtual water trade in agricultural products between Germany and China during the period 2008–2010. Germany exported 192 million m3 of virtual water to China and imported 801 million m3 from China. Through the bilateral trade, Germany saved 69.8 million m3 water, while China had a net water loss of 469.4 million m3. Thus, the global water loss amounts to 399.6 million m3.  相似文献   

5.
若尔盖高原的降水量微弱减少与蒸发量持续上升,使若尔盖高原径流量与储水量逐年降低,直接减少了若尔盖高原的湿地面积和对黄河上游径流量的补给。基于红原、若尔盖和玛曲站的气象数据和7个水文站的径流量数据(1981-2011年),并对数据序列进行插补与计算,获得若尔盖高原的径流量变化与气候因子的响应关系,进而计算储水量变化。计算结果表明:若尔盖高原向黄河年均补水(67. 08±14. 90)×108m3,并以0. 48×108m3/a速率持续减少。降水量每减少1 mm将导致黑河与白河的年径流量分别减少0. 02×108和0. 05×108m3。蒸发量每增加1 mm将导致黑河与白河的年径流量分别减少0. 12×108和0. 27×108m3。1981-2011年若尔盖高原的年均储水量为(59. 30±18. 69)×108m3,其年均递减速率为0. 49×108m3/a。本研究有助于认识若尔盖高原对于黄河上游水资源保障的重要性。  相似文献   

6.
生态补水对于恢复受污染水体的自然属性以及重建河道的景观功能具有重要作用。为配合滇池水体整治,本文以典型入滇河流昆明老运粮河为研究对象,基于其蓄洪、生态调节与保育及景观水体的功能界定并计算其生态需水量,同时考虑补水成本经济性进行基于满意度的需水量修正。修正后,支流小路沟、七亩沟生态需水量分别为3 100和19 000 m3/d,下游入湖段生态需水量为34 000 m3/d,其生态-经济满意度依次为80%、80%、100%。本研究对城市人工河道生态需水量的计算及基于实际的成本-效益权衡问题进行了有意义的实践,为城市人工河道补水工程的方案设计提供了一定参考价值。  相似文献   

7.
为实现用水总量的控制目标,从控制用水强度、提高水资源利用效率两方面出发,利用比拟借鉴方法构建了雄安新区不同时期分行业、分区域的用水强度指标体系。针对用水强度指标的不确定性,利用随机模拟方法预测了雄安新区不同时期需水总量,并进行统计分析。结果表明:雄安新区建设期、建成期、腾飞期最小需水量在7.5亿m3以内,平均需水量为8亿m3左右,最大需水量达到9亿m3;建议在建立先进用水强度指标体系的基础上,严格用水强度指标的执行监管,确保用水强度指标落地见效,全面推广生活、工业、农业先进节水技术,加强非常规水资源利用,促进水资源高效循环利用。  相似文献   

8.
为降低农业生产活动中农作物对水资源的高消耗,提高用水效率,借助辽宁省1987—2018年19个气象站点逐日气象数据及春玉米产量数据,全面计算绿水足迹、蓝水足迹及灰水足迹的真实消耗。结果表明:(1)辽宁省春玉米生产水足迹自2002年起变化幅度不明显,多年平均值是1424.21 m3/t,其中绿水足迹占54%,灰水足迹占27%,蓝水足迹占19%。(2)从绿水足迹看,辽宁省春玉米绿水足迹每年以6.28 m3/t速率减少,空间分布上2002年绿水足迹高值区主要集中在东部地区;2010年辽宁省整体绿水足迹较高。(3)从蓝水足迹看,每年以1.06 m3/t的速率增长;2002年辽宁春玉米蓝水足迹高值区主要分布在环渤海、宽甸及其周围地区;2010年,辽宁省大部分地区蓝水足迹较低。(4)灰水足迹整体以每年14.03 m3/t的速率降低,主要与农作物产量及氮肥施用量相关。  相似文献   

9.
Water Footprint of Grain Product in Irrigated Farmland of China   总被引:1,自引:0,他引:1  
China faces the dual challenge of grain production pressure and water scarcity. It is significant to reduce water footprint of grain product (WFGP, m3/t) in irrigated farmland. The focus of grain production and agricultural water use, and the precondition is to determine the WFGP and its composition. This paper estimates the WFGP in irrigated farmland of 31 provinces (including municipalities, autonomous regions) a by collecting actual data of 443 typical irrigation districts in 1998, 2005 and 2010, and analyses its temporal and spatial variation in irrigated farmland of China. The result shows that the WFGP in each province decreases with time except in Jiangxi and Hunan, and the average value of all provinces reduced from 1494 m3/t in 1998 to 1243 m3/t in 2010. The WFGP decreases faster in more developed municipal cities and major grain production provinces. The annual average WFGP in irrigated farmland is 1339 m3/t and the blue and green water account for 63.5 % and 36.5 % of the total, respectively. The WFGP and its composition are significantly different between provinces. Generally, provinces distributed inside and beyond Huang-Huai-Hai Plain, have a higher water productivity, lower WFGP and blue water footprint of grain product, while most provinces located in northwest, northeast, southeast and south China have a higher WFGP and lower proportion of green water in the WFGP as a whole. Portion of the blue water footprint (BWFGP) is not consumed for crop evapotranspiration (BWFGP ET ) but conveyance loss (BWFGP cl ). The national averaged BWFGP cl decreases with time and but still remains up to 466 m3/t in 2010, making up 34.8 % of the WFGP. In order to safeguard grain security and ease the water resource pressure, the Chinese government should increase investment and apply advanced technology for developing water-saving agriculture, improve the efficiency of water use and further reduce the WFGP. Considering also the contribution of grain output and the relatively high WFGP, the government should give priority to developing water-saving agriculture in the Northeast of China.  相似文献   

10.
Given the high level of capital investment and the history of government subsidized services, full cost pricing of water services has yet to take hold in India. As a result, it remains broadly underpriced leading to public perception that water is "free" The current tariff levels in India are too low to cover even operating costs. This paper examines the existing Indian urban water tariff models (fixed tariff, volumetric tariff, increasing block tariff etc.), their relevance and problems. It was found that none of the tariff structures could satisfy all the design objectives (cost recovery, economic efficiency, equity, affordability etc.). Also subsidies are not explicit and well targeted for poor population. There are several studies and issues that do demonstrate the opportunities for tariff increase and improved cost recovery. This paper highlights the results of such studies and brings out issues needing consideration. Improved cost recovery would lead to improved financial status of the water utilities. Also, subsidies, if designed suitably and well targeted, would serve the concerns of the economically weaker sections. Such reform process would eventually lead to socio-economic sustainability.  相似文献   

11.
Wenying Lake in Datong, China, has been drying for the last several years. Analysis of standard penetration test data revealed that a missing waterproof layer of silt soil and silty clay in the south part of the lake, resulting from frequent flood flushing, was responsible for the water loss from the lake. Accordingly, 6.7 × 105 m2 of geosynthetic clay liner (GCL) was used in May 2010 to repair the area of sediment exhibiting the water leakage, equivalent to 15.6% of the total lake bottom area. Approximately 4.1 × 106 m3 of floodwater was then diverted from upstream rivers to the lake. Eight months later, about 0.9 × 106 m3 of the water was retained, with the water loss being reduced from 4.0 to 1.1 m3 m?2 year?1. Ecologically safe and cost‐effective clay materials also can be used to furthermore improve the water retention characteristics. Modelling results indicated that capping the whole lake with a 2 cm layer of bentonite with a permeability coefficient of 5.0 × 10?9 cm s?1 could reduce the sediment water leakage to 0.04 m3 m?2 year?1. The quality of the retained water after GCL treatment project was poor, with a total nitrogen concentration of 11.0 mg L?1 and sulphate 307.0 mg L?1, which were 5 and 300 times higher, respectively, than the Chinese class V surface water standard. Restoration of aquatic vegetation in the lake and constructed wetlands near the lake inlets could be helpful to improve the lake’s water quality over the long term.  相似文献   

12.
京津冀协同发展战略及河北省沿海地区发展规划的提出,促进了环渤海经济圈的发展,沧州渤海新区地处环渤海经济圈的核心地带,城市化进程不断加快,使得水资源需求变大,加重了水资源短缺的形势。本文通过分析、统计新区的气象、水量及规划数据,计算了沧州渤海新区的供需水量。结果表明:到2020年需水量约为4.03×10~8m~3/a,预期可供水约3.27×10~8m~3/a,水资源缺口近7600×10~8m~3/a。运用ENVI软件解译黄骅海域的遥感影像,预期新区可开采海冰量约为1.76×10~8m~3,供水约为8 800×10~8m~3/a。因此,沧州渤海新区的海冰储量可观、淡化成本低、水质好,淡化水可替代生态及部分工业用水,海冰资源的开发利用的前景广阔,可行性高。在新区内尝试开发利用海冰资源不仅可以减轻灾害损失,缓解水资源短缺问题,还为我国其他饱受海冰灾害影响的沿海地区提供参考和指导。  相似文献   

13.
Ecological water use (EWU) is urgent in need in the lower reaches of Tarim River in China. Estimation of water amount for EWU is depending on some parameters and modeling. EWU is mainly consists of two parts in no runoff area in the basin, i.e. total water amount for restoration groundwater table and total stand water amount of the all river courses. The former is including water amount for restoration of groundwater table, lateral discharge and evaporation of water surface. The estimated values are 8.18 × 108 m3, 0.68 × 108 m3/a and 0.132 × 108 m3/a respectively. Based on the groundwater depth rising 4.0 meters requiring 5 years, the total water amount for restoration groundwater table is 2.448 × 108 m3/a. The latter, i.e., total stand water amount is 1.992 × 108 m3/a. However, the development of water management measures could alleviate the issue and lead to sustainable EWU in the lower reaches of Tarim River.  相似文献   

14.
为分析黄河流域粮食生产用水的可持续性,引入水足迹和虚拟水相关理论方法,对研究区主要粮食生产水足迹及粮食贸易伴生的虚拟水流动格局进行了量化解析,并对未来粮食生产水足迹进行了预估。结果表明:2011—2016年,全流域粮食生产总水足迹和单位水足迹分别由460亿m^(3)和1.20 m^(3)/kg降为402 m^(3)和0.93 m^(3)/kg,均呈下降趋势;从粮食贸易伴生的虚拟水流动特点来看,流域全口径粮食虚拟水从2011年的110.7亿m^(3)减小到2016年的50.3亿m^(3),呈输入态势;除稻谷之外的粮食虚拟水由82.6亿m^(3)增加到193.4亿m^(3),呈输出态势;在流域不同气候情景下,2035年粮食生产总水足迹为481.9亿~518.7亿m^(3),其中绿水足迹增幅达20%,而蓝水足迹增长不显著;未来流域内粮食输出量的增加会进一步加剧本地农业生产的用水矛盾,但粮食灌溉总用水量的增速可能放缓。  相似文献   

15.
Effects of multiple types of water use efficiency appliances on long term water savings and water use trend shifts were analyzed. The study group included senior and low income families in the urban areas of Miami-Dade County, Florida, USA. The participants in the study group experienced continuous and significant water savings within 3 years of the implementation of the water conservation incentives. Water savings were observed at approximately 200 l per household per day, which is about 31 % reduction in household water demand in comparison to the average residential water demand within the County. The water use profile of participants showed noticeable shifts over time in water demand frequency curves toward lower water consumption rates. The cost-saving analysis showed that adoption of multiple water efficiency appliances contributed to the highest annual monetary savings (i.e., high water savings and moderate product costs). Future conservation program planning efforts should take both water savings and product cost into account in order to achieve the greatest benefits.  相似文献   

16.
Located in the centre of the Eurasian Continent, the Turpan Basin, as the second deepest lowland in the world, is extremely short of water resources. Aimed at this key scientific issue, this paper based on years of meteorological and hydrological observation data, carried out a scientific calculation and evaluation of surface and groundwater resources in the Turpan Basin, and then, with the help of modified Penman formula, calculated the virtual water potential in the basin in 2004. The results show that the average total usable surface water resources per year in the last decade were about 6.673×108 m3, while adduction volume of surface water in 2003 was about 4.94×108 m3, which means that most of the region has reached or approached the limit of water resources and, as a result serious crises and constraints on the development of the basin were thus caused. The exploitation content of groundwater in the Turpan Basin in 2003 was about 6.12×108 m3, which has basically reached its upper limit, and the ground water level has fallen about 10~40 m in the Turpan Basin in recent years. The daily reference crop water requirement in the Turpan Basin in 2004 was about 1,053.39 mm, and the total virtual water potential contained in six main crops was about 5.25 ×108 m3 in 2004. All these showed that research works on scientific assessment of water resources and regional virtual water strategy have great significance for the best social, ecological, economic benefits and regional sustainable development of the Turpan Basin.  相似文献   

17.
构建南水北调东线工程江苏段水资源优化调度模型,采用改进的多目标量子遗传算法(multiobjective quantum genetic algorithm,MOQGA),运用组合赋权方法对非劣解集进行多属性决策,提出南水北调东线工程江苏段水资源优化调度方案。在平水年、枯水年和特枯水年3种典型年来水条件下,相对于常规调度,优化调度的受水区总缺水量分别减少了0.89亿m3、0.87亿m3和0.08亿m3,系统总抽水量分别减少21.04亿m3、39.14亿m3和50.76亿m3。该优化调度方案能够充分利用湖泊的调蓄能力,提高各用水户的需水满足度,降低抽水成本。  相似文献   

18.
Role of Virtual Water in Optimizing Water Resources Management in Jordan   总被引:2,自引:2,他引:0  
Role of virtual water (VW) in optimizing water resources management in Jordan, a far water-short country, was explored by calculating VW content of imported commodities and their costs. Feasibility of farming and water required to produce all crops growing in Jordan were evaluated using net return per unit volume of water and VW embedded in unit mass of production. The results of these analyses showed that there were regional differences in crop profitability and thus net return from unit volume of irrigation water. This was attributed to variations in agro-climatic zones punctuated by production and irrigation technologies and access to water resources. In this regard, opportunity cost of water should be considered when allocating water to different consumption sectors. Agricultural systems generating net profits less than an arbitrary limit of $1.0?m?3 of irrigation water and producing yield at water use efficiency of 50?C60?m3?ton?1 or more were viewed not feasible. The key challenge facing decision makers would be to ensure that the opportunity cost of water was incorporated into the analysis process when determining future cropping pattern. Such a cost of water should be combined with crop-embedded VW analysis and expected net return from unit volume of irrigation water. Therefore, water allocation mechanism (e.g. water market) need to be developed for more efficient water use than the commonly practiced farm quota. Optimization of the usage of the limited water resources can be envisaged by continuous imports of VW, especially that embedded in cereal, oil, meat, live animals and sugar. Appropriate amendment of water legislations and concerned institutions are encouraged to provide better guidelines to policy makers, water managers, extension and advisory services, water use associations and farmers. Optimization of water resources management could be based on contract farming to ensure that water allocation and cropping pattern respond to water scarcity. Furthermore, Jordan should concentrate on production and export of crops having low VW contents and high return per m3.  相似文献   

19.
The water footprint (WF) of crop production is a comprehensive indicator that can reflect water consumption types, quantities and environmental impacts during the crop growth period. This study assesses interannual variability of green, blue and grey WFs of maize production in Beijing from 1978 to 2008. Results indicate that: (1) The multi-year average WF of maize was 1,031 m3 ton?1 which was 56 % green, 25 % blue, and 19 % grey; (2) the climate experienced a warm-dry period in Beijing during the period from 1978 to 2008, and this lead to the increase of crop water requirement and irrigation water requirement for maize with trends of 0.52 mm a?1 and 2.86 mm a?1, respectively; (3) under the combined effects of climate change and agricultural inputs, the total WF and green WF presented decreasing trends. The blue and grey WFs had clear increasing trends; (4) statistical analysis revealed that interannual variability of green and blue WFs were caused by both climatic factors (effective precipitation) and non-climatic (agricultural inputs) factors. The grey WF was mainly associated with non-climatic factors, such as chemical fertilizers consumption.  相似文献   

20.
Water is vital for economic development and environmental sustainability in arid and semi-arid basins. Management of water resource requires good understanding of available water for human consumption. Evapotranspiration (ET) is an important component of the hydrological cycle and represents the amount of water lost to the atmosphere in a basin. This study proposes a new approach to estimate available consumable water for human activities (ACW) in a basin based on precipitation, natural ET, and uncontrollable outflow, thus capping water use for human consumption in a basin. The ACW is illustrated for the Hai Basin in North China, where the average ACW from 2001 to 2012 for the entire basin is estimated at 31.97?×?109m3 yr.?1, varying between 18.61?×?109m3yr?1 in 2002 and 42.60?×?109m3yr?1 in 2003. A water balance analysis for the basin indicates that the aquifer water depletion in Hai Basin for 2001–2012 is 5.23?×?109m3yr?1. Compared to existing water resources assessment, ACW provides an easier approach to water management planning as no hydrological data are required, only data on precipitation and ET, supported by landcover data.  相似文献   

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