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1.
运用系统分析的理论和方法,建立湖南省水资源供需系统模型,仿真模拟传统发展型、发展经济型、节水型、协调型等4种不同方案条件下,2010~2030年湖南省水资源供需变化趋势。结果表明:(1)随着经济发展和人口增长,水资源供需矛盾将日趋紧张;(2)在协调型模式下,水资源供应基本能够满足社会经济发展的需要,且用水效率最高,是湖南省水资源开发利用的最优方案;(3)为了实现节水型社会建设目标,还需完善用水管理、优化经济结构、加快水利建设、加大循环利用和环境整治,提高节水技术水平和水资源保障水平  相似文献   

2.
Linear programming (LP), a well-established technique for modelling agricultural and other systems, has been extensively used to model irrigation systems in Australia. The models constructed have been used to assess the effects of changing water charges on farm incomes, water use, and the effects of trade in water allocations. An LP model that reflects actual farm behaviour requires a large amount of data. Moreover, demand and supply functions estimated with LP models are necessarily stepped rather than smooth. Howitt has suggested a way of escaping from these problems of LP models. His positive programming approach replaces an LP model with a simpler quadratic programming model. In this paper, Howitt's approach is used to develop a quadratic programming model from an existing LP model of irrigated agriculture in the southern Murray-Darling basin of Australia. A comparison of the quadratic and linear models indicates that the quadratic programming model is smaller and simpler to specify and that it produces similar results to the linear model, in terms of cropping, trade, and demand for irrigation water. The choice of modelling technique depends on the problem and the available resources. Positive programming can be a valuable addition to the farm modellers' arsenal.  相似文献   

3.
根据最新的水资源调查评价结果,分析了中国水资源的现状和特点:总量丰富,但人均占有量低;年内年际分配不匀,旱涝灾害频繁,水资源供需矛盾突出;地区分布不均,水土资源不相匹配;水资源利用率低,污染严重。在此基础上,分析了我国水资源安全目前存在的主要问题:水资源时空分布不均严重阻碍社会经济发展;水资源供需矛盾严重,水资源利用效率低下;水质危机导致水资源危机,生态环境恶化严重;水资源管理缺乏科学体制。认为21世纪中国的水资源矛盾将进一步加剧,我国必须进行大规模的改革和强有力的措施,包括节约用水,建立节水型工业,提高用水效率,加强水污染防治,引入市场机制,加强科技创新,树立可持续发展的思想,实行水资源的统一科学管理,维护我国的水资源安全,以缓解我国水资源的供需矛盾,实现经济和社会的可持续发展。  相似文献   

4.
上海地处长江三角洲平原河网地区,水资源总量较为丰富,但伴随着区域社会经济快速发展,水体水质污染普遍,水资源的可利用性不高,水质型缺水现象日益严重。分析了上海地区水资源的组成和总量状况,进一步论述了目前上海水资源利用面临水质污染严重、供需矛盾突出和利用效率低下等问题,在此基础上提出了通过强化地表水环境综合整治,提高城市水资源利用效率,构建两江并举的水源格局,完善水资源经济调控手段,加强全民水资源保护意识等对策措施实现上海水资源可持续利用与管理。  相似文献   

5.
城市绿地生态系统合理供水辨识分析   总被引:1,自引:0,他引:1  
城市绿地因具有美化环境、降低空气污染、控制城市热岛等作用而日益得到重视。合理的城市生态供水不仅有益于植被的正常生长,对城市水资源合理配置同样具有积极意义。为统筹城市生态与国民经济发展,保证绿地健康,需要合理的绿地供水管理。本文以土壤含水量为标准,根据田间持水量、临界土壤含水量和凋萎系数三个土壤含水量值划分不同等级的绿地需水量,将供水量分为四个等级,建立了城市绿地供水合理性评价模型,为有效辨识供水合理性提供了参照依据。以2009年北京市城市绿地供水为例,进行了供水合理性分析,结果表明,从全年来看,供水基本合理,虽然绿地蒸散发受到一定抑制,但不影响植被生长;从逐月供水来看,个别月份存在供水过少或过多现象,影响植被生长,且不利于水资源合理利用。  相似文献   

6.
在当前保障性住房供给与需求矛盾不断加深的背景下,研究保障对象对保障性住房的租赁或购买的需求特征及其关键影响因素,具有较强的必要性与现实意义。本文通过问卷调查方式获取城市中心城区受保障对象的需求特征数据,从保障对象住房需求的视角,分析影响保障性住房租赁或购买选择的相关因素。文中构建了Logit模型,并检验各因素对保障性住房租购选择的影响关系及强度。结果显示:(1)住区环境、个体特征、家庭特征、住房特征等四大类因素对保障性住房租购选择产生显著的影响;(2)住区环境中,教育资源、交通配套设施等是影响保障性住房租购选择的关键指标,这些关键指标的改善,将会使保障对象更倾向于购买保障房而不是租赁;(3)个体特征中,性别与年龄对保障性住房租购选择影响最大,相比男性、年轻人,女性、年长者更倾向于购买保障性住房而不是租赁;(4)家庭特征方面,人口数量多、经济收入高等特征的家庭更愿意选择购买保障房,但家庭人口数量的影响大于家庭经济收入;(5)住房特征中,居住稳定性对保障性住房租购选择影响最大,其次是保障性住房准入政策合理性、住房面积及户型,这些因素的改善,都将提高保障对象对保障性住房做出购买的决策。因此,提供多形式、多条件的保障性住房,才能满足不同保障对象的租赁或购买的需求。设置合理的保障性住房准入条件,构建科学合理规范的保障性住房供给标准和住房保障运行机制,才能使迫切需要租购保障房的家庭从中受益。  相似文献   

7.
The ECOSYS model is the ingestion dose model integrated in the ARGOS and RODOS decision support systems for nuclear emergency management. The parameters used in this model have however not been updated in recent years, where the level of knowledge on various environmental processes has increased considerably. A Nordic work group has carried out a series of evaluations of the general validity of current ECOSYS default parameters. This paper specifically discusses the parameter revisions required with respect to the modelling of deposition and natural weathering of contaminants on agricultural crops, to enable the trustworthy prognostic modelling that is essential to ensure justification and optimisation of countermeasure strategies. New modelling approaches are outlined, since it was found that current ECOSYS approaches for deposition and natural weathering could lead to large prognostic errors.  相似文献   

8.
《Environment international》1999,25(6-7):701-712
Meeting the challenge of sustainable development requires substantial advances in understanding of the interaction of natural and human systems. The emerging ecosystem management paradigm of multiple stable states, non-linear systems behaviour, discontinuous change, self-organisation and multiple development pathways has major implications for when and how change in complex systems occurs and how it can be managed. It also poses considerable challenges for modelling the structure and function of natural and human management systems, including fundamental constraints relating to: scaling mismatches, synthesis of non-homogeneous information, multiscaled system interactions, complex management systems, uncertainty in causal relationships, assessment of trade-offs, and validation. This paper examines how a decision support system (DSS) for sustainable grazing management, called Landassess DSS, attempts to deal with some of these issues through an integrated systems approach to DSS development. This approach utilises object-oriented techniques, knowledge-based systems, geographical information systems (GIS), and a state-and-transition model framework to model the critical change processes. It provides for the identification of the major driving factors and constraints to change in complex resource management systems, as well as the assessment of the likely trade-offs between resource sustainability and economic production at a scale relevant to management decision-making (i.e., paddock or property).  相似文献   

9.
我国水资源需求量动力学预测及对策建议   总被引:6,自引:0,他引:6  
水资源是社会经济发展的重要物质基础和不可替代的自然资源。要实现党的十六大提出的全面建设小康社会的宏伟目标,水资源是必不可少的支撑条件。通过动力学模型,对未来20年我国工业、农业和生活需水量及总需水量进行预测,预测结果表明:按方案1,到2022年我国需水量约为5 500亿m3,按方案2,需水量约为7 400亿m3。而到2022年全国供水能力可能达到6 500亿m3 左右,可供水量为6 100~6 500亿m3 。方案1的预测结果小于可供水量,但这种方案很难实现。方案2的预测结果大于可供水量,出现较大缺口,在GDP增加1%的情况下,需水量增加1 800亿m3 左右,这也是我们面对的现实问题。  相似文献   

10.
随着滇池治理的进展,在今后一个时期内,恢复滇池饮用水环境功能,成为滇池治理的首要目标和任务。围绕滇池流域水资源供求平衡,采用水资源全要素配置框架下的三次平衡分析理论,从整体上分析了滇池流域水资源供求平衡关系及存在的主要问题,提出了以需求为导向,建立滇池流域水资源综合平衡管理目标和措施。分析表明:在滇池治理的基础上,通过建立滇池流域水资源综合平衡管理体系,落实管理措施,从总量平衡的理论上能够充分发挥引水工程的作用,恢复滇池饮用水环境功能,实现水量、水质供求的综合平衡。建议进一步开展量化分析和模拟实验研究,为在滇池流域实施综合平衡管理提供可靠依据和建议  相似文献   

11.
变革中的中国水资源管理   总被引:2,自引:0,他引:2  
水资源短缺是世界面临的共同危机,是制约国民经济健康稳定发展的重要“瓶颈”,水资源的可持续利用已经成为经济社会可持续发展的基础性、战略性问题.缓解水资源供需矛盾的关键是加强水资源的管理.文章回顾了中国水资源管理制度的发展演变历程:只管工程的非正式水资源管理、行政命令为主的正式制度萌芽、取水许可管理和基于水权的正规制度管理等四个阶段.尽管在确立以流域管理和区域管理相结合的综合管理体制,建立以水量分配、取水许可、水资源论证为主要内容的水权管理制度和以全成本核算为原则的水价管理制度等方面成绩显著,水资源管理中仍存在水资源权属不清、水环境权得不到保障等问题.今后中国水资源改革,首先应继续深化水权改革,推动水权明晰化,建立水权交易制度;其次,健全水环境权的法律法制规范,提供相关的法律保障;最后,完善部门间的合作协调机制,真正实现对水的协同管理.  相似文献   

12.

The management of large-scale water resources systems requires including of different stakeholders and users from municipal, agricultural, industrial and environmental sectors. This has baffled the process of decision making for integrated water resource systems. In such systems, the interactions between various stakeholders must be carefully taken into account with the goal of aggregating interests around the sustainability concept. In this study, first, the integrated water resources systems of Big Karun Watershed, Iran, have been modeled using the system dynamics approach. The system dynamics model represents the interactions between different components of the system, including water transfer projects, dams, urban, industry, agriculture and fish farming, and environmental demands. Vensim software has been used for the system dynamics modeling. Vensim simulates the dynamics behavior of the sub-systems and overall performance of the system by comparing the current operation policies with the future management scenarios. A wide range of performance indices, such as quantitative and qualitative water stress, income, cost, and productivity, have been used here to represent different aspects of sustainability goals. Finally, the performance of the systems has been evaluated by developing a sustainability index using distributed zoning model in order to identify proper management policies for this watershed. The results indicate that downstream users demand cannot be fully met by solely considering inter-basin water transfer and agricultural development projects. The sustainable and integrated management of the whole system ties into enhancement in both infrastructure systems and the operation of the whole system. It is expected that the sustainability of the basin improves if a water market schema exists and the gained money would be used to enhance the efficiency of existing irrigation networks.

  相似文献   

13.
太湖流域水供给服务供需时空演变分析   总被引:5,自引:0,他引:5  
太湖流域是我国经济发展最快、人口最密集的地区之一。受土地利用和降水条件变化的影响,太湖流域水供给服务供需关系也发生着变化。通过分别设置1995~2015年太湖流域不同降水条件和土地利用变化情景,利用Invest模型定量评估水资源供给量,同时利用空间离散法定量评估水资源需求量,并进一步分析供需赤字和盈余区域的时空变化。结果表明:1995~2015年随着土地利用变化,尤其是建设用地的扩张(20年来涨幅达106%),水资源需求占供给量的比重由73%升至90%,需要依赖外来客水的县域面积占整个流域的比重由19%升至33%;2015年在不同降水条件下供需关系变化更为明显,降水量越少,供需赤字的县域越多,在干旱年份整个流域需求量占供给量的117%,供给量已不能满足需求量,且赤字县域的面积占整个流域的47%。两种情境下,太湖流域东北部水供给服务供需关系均比西南部紧张。作为影响太湖流域水资源供需变化的主要因素,土地利用和降水条件变化分别通过影响需求量和供给量改变供需关系。  相似文献   

14.
基于水足迹的流域生态补偿标准模型研究   总被引:6,自引:2,他引:4  
流域水资源是一种公共物品,其系统的整体性以及资源外部性等特征要求各相关区域应共同承担环境保护.如何衡量各区域水资源开发利用与环保投入的关系,建立合理的生态补偿标准模型,已成为流域管理研究领域普遍关注的问题.本文运用水足迹理论和方法,界定流域水足迹内涵,通过反映流域沿岸各区域水生态服务耗费情况判断分析水生态系统安全状态,提出流域生态补偿标准计量流程及不同情况下的流域生态补偿标准测算模型,从而客观、准确地量化流域生态补偿额度,为管理者正确分析和解决流域各区域间利益冲突提供科学的决策依据与支持.同时本文以碧流河为案例,收集并分析了2002-2006年间碧流河沿岸各行政区水足迹和环保投入情况,理清各区域生态系统状态及相互关系,计算补偿标准,进而验证模型的可行性.  相似文献   

15.
Defect and Innovation of Water Rights System   总被引:1,自引:0,他引:1  
The rare deposition of water resources conflicts with its limitless demand. This determined the existence of the water rights transaction system. The implementation of the water rights transaction system requires clarifying the definition of water resource right above all distinctly. At present, it is a kind of common right system arrangement which needs the Chinese government to dispose of water resources. Though a series of management systems guaranteed the government's supply of water resource, it hindered the development of the water market seriously and caused the utilization of water resources to stay in the inefficient or low efficient state for a long time. Thus, we should change the government's leading role in the resource distribution and really rely on the market to carry on the water rights trade and transaction. In this way, the water rights could become a kind of private property right relatively, and circulate freely in the market. As a result of this, we should overcome the defects of common right, make its external performance internalized maximally and achieve the optimized water resource disposition and use it more effectively.  相似文献   

16.
Abstract

The rare deposition of water resources conflicts with its limitless demand. This determined the existence of the water rights transaction system. The implementation of the water rights transaction system requires clarifying the definition of water resource right above all distinctly. At present, it is a kind of common right system arrangement which needs the Chinese government to dispose of water resources. Though a series of management systems guaranteed the government’s supply of water resource, it hindered the development of the water market seriously and caused the utilization of water resources to stay in the inefficient or low efficient state for a long time. Thus, we should change the government’s leading role in the resource distribution and really rely on the market to carry on the water rights trade and transaction. In this way, the water rights could become a kind of private property right relatively, and circulate freely in the market. As a result of this, we should overcome the defects of common right, make its external performance internalized maximally and achieve the optimized water resource disposition and use it more effectively.  相似文献   

17.
农地非农化中不同利益主体博弈行为分析   总被引:2,自引:0,他引:2  
随着我国社会经济的发展,城市的加剧扩张和建设用地需求的不断增长而带来的农地非农化在近年来表现得尤为突出,已经严重影响着我国的粮食安全和生态安全.因此,从决策主体行为出发,研究农地非农化问题,对于我国城市化的正常推进以及农地的有效保护具有重要的现实意义.本文从博弈论的角度探讨农地非农化过程中相关利益主体的行为倾向和博弈关系.研究结果表明:(1)中央政府应该加大给予地方政府和农民进行耕地保护的奖励以及提高违规的惩罚力度,抑制农地非农化的速度,遏制违法占用,提高土地的利用率,减少耕地资源的闲置和浪费;(2)中央政府和地方政府应完善相关政策,缩小城乡土地价格差异,提高征地补偿标准,逐步建立公正的补偿机制和科学合理的补偿标准;(3)地方政府应进行土地利用制度和模式的创新,注重力拓土地后备资源,盘活存量资源,减少建设占用农地,不仅能有效地解决经济建设和耕地保护的两难困境,而且能有效地保护生态环境,实现土地资源的可持续合理利用.  相似文献   

18.
根据区域建设用地的极限供需状况制定区域差别化的建设用地管控政策,有利于建设用地总量控制目标实现和建设用地的精细化管理。以扬州市为实证区域,构建基于资源环境容量约束的建设用地极限供给与经济发展驱动的建设用地极限需求的测度模型,以期为区域差别化的建设用地管控提供参考。研究表明:(1)扬州市建设用地极限供给总规模为 162 686.44 hm,未来建设用地可拓展空间总体上呈现南多北少的特征;(2)扬州市建设用地极限需求规模为 158 164.63 hm,南部地区高于北方;(3)扬州市建设用地极限需求不会突破资源环境容量约束的极限供给上限,其中仪征市和高邮市的极限需求规模超出极限供给规模,市区、江都区和宝应县极限需求规模小于极限供给规模;(4)仪征市与高邮市应根据极限供给规模严格控制建设用地总量,提高建设用地利用效率,降低经济发展对土地要素的过度依赖;市区和江都区可构建区域的协同一体化发展战略,适当扩张建设用地规模,优化区域建设用地空间布局;宝应县应注重耕地保护,予以适度的建设用地指标倾斜,促进经济增长与耕地保护协调发展。 关键词: 建设用地;供需分析;区域分异;扬州市  相似文献   

19.
中国区域能源安全供给脆弱性分析   总被引:4,自引:0,他引:4  
随着经济持续快速发展,我国能源需求不断增加,能源安全,尤其是石油安全问题日益突出,而能源安全供给脆弱性是能源安全的核心问题.在对能源安全供给脆弱性概念进行界定的基础上,构建了脆弱性评估模型以及由对外依存度、能源消耗弹性指数、能源储量比、能源生产弹性指数、运输线路长度和人均GDP构成的评价指标体系.采用因子分析法确定评价指标的权重系数,并对全国30个省(市、区)"十五"时期的常规能源(煤炭、石油和天然气)安全供给脆弱性进行定量评估.结果表明:①我国区域能源安全供给脆弱性程度整体上处于中等偏下水平,且呈现出"东高西低"的特征;②能源安全供给风险的应对能力差异是区域脆弱性分异的主导因素.  相似文献   

20.
The article used general equilibrium model to analyze the change of gross domestic product and industry output affected by water resources policies in Beijing City by using GEMPACK soft tool.The article researches on rules of water supply and demand,evaluating water resources,building water resources input and output table,establishing water computable general equilibrium model and stimulating water policy.The stimulation gives a scenario that increases water price by 10%.The result shows the following aspects.First,water resources policy infects gross domestic product and industry output in different ways.There are different behaviors in different industries as to the water policy.Agriculture industry has the same tendency as water price change and it has more sensitive to water quantity than to water price.For basic energy industries such as oil and chemistry and gas,they show diversity tendency.As to some high water consumer industry such as paper and textile etc.,water resource economic policy can infect them greatly and can promote them to accomplish more water-saving technology.Waste water and construction and service industries show the same tendency as to water policy.Second,government should pay more attention to water resource policy by macro economic administration.The simulation also shows that the output and supply and consumer price change more than expect as to water policy in a free market economic in water industry.So as to a government policy maker,one should be more carefully and prepare suitable forecast and plan to water policy and its negative impact.  相似文献   

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