首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 312 毫秒
1.
The aim of this paper was to analyse Business-As-Usual (BAU) scenarios for addressing the eutrophication issue of the Po Basin-North Adriatic coastal zone continuum. A multidisciplinary approach was developed combining Ecologic and Economic disciplines being a relevant step for shaping cost-effective strategies aiming to achieve the water quality targets as required by the Water Framework Directive (WFD) 2000/60/EC and by the Italian D.lgs. 152 of the 2006. The BAU scenarios analysed suggest an increase of nutrient load (2.1–4.6% for nitrogen and 0.4–5% for phosphorus) if the current programme of measures will not be modified implying that Water Qualitative Objectives (WQOs) will not be achieved by the year 2015 (Art. 4 of WFD). The methodological approach described in this paper should be used as Decision Support System (DSS) aiming to support environmental planning process under both the WFD and the Italian D.lgs. 152 of the 2006.  相似文献   

2.
A great challenge of the current European water policy is the implementation of volumetric water pricing in the agricultural sector, especially of Mediterranean countries, where irrigation is a necessary precondition of agricultural production and farmers’ income, but also the major consumer of water. The overall aim of the present work is to develop a methodology that will be suitable for the estimation of the potential environmental, economic and social impacts of irrigation water pricing. For this purpose, Multi-Attribute Utility Theory is implemented in order to simulate agricultural decision making at various water pricing scenarios. Water demand functions are then elicited, by means of the best crop and water allocation (farmers’ decisions) in each scenario. The European Water Framework Directive recommends that any issue concerning water resources management (including water pricing policies) should be developed at the river basin level. In this framework, a cluster analysis is performed to partition the river basin area (namely, Loudias River Basin, located in Northern Greece) into a small number of homogeneous sub-regions. The differential impact of water pricing in each region is then analyzed, and finally, an average water demand function is formulated for the whole river basin.  相似文献   

3.
This paper presents an application of residual value techniques to the economic analysis of irrigation water at the basin level for the Guadalquivir River (Southern Spain). The methodology is simple; the results are robust and consistent with alternative method findings. The average residual value in the basin is 0.31 €/m3 and according to the to Residual Value Method, the distribution of total Gross Value Added (GVA) of irrigated land is distributed between the different factors of production as follows: (i) water, 62% of GVA; (ii) land, 20% GVA (from rain-fed productivity), (iii) return to man-made capital, 5% GVA; and finally (iv) the pair ‘management + family-labour’ gets 13% of total irrigation GVA. The paper illustrates the use of this method for the whole basin and it shows that it may offer promise for supporting sustainable water management at the basin (or the local) scale. It may be used for the implementation of the Water Framework Directive.  相似文献   

4.
Water scarcity is a common problem in many countries, especially those located in arid zones. The vulnerability of water resources due to climate change is an imperative research focus in the field of water resources management. In this study, a System Dynamics (SD) model was developed to simulate the water supply-and-demand process in Bayingolin, a prefecture in China, and to evaluate water resources vulnerability currently as well as in the future. The model was calibrated and validated using historical data. Three alternative scenarios were designed by changing parameters to test the vulnerability of water resources: i) increase the Wastewater Treatment Rate by 50 %; ii) decrease the Irrigation Water Demand per Hectare by 20 %; iii) increase Total Water Supply by 5 %. Results show that the baseline vulnerability of study region is high. The agricultural irrigation is the largest water use, and the water demand structure will change in future. Decreasing the irrigation water demand is the most suitable intervention to relatively reduce the vulnerability. Results also demonstrated that SD is a suitable method to explore management options for a complex water supply and demand system.  相似文献   

5.
Countries' social and economic policies as well as their priorities and preferences determine irrigation water pricing; it is a very complex, multi-dimensional and unknown problem in all countries. There is no guiding principle; therefore many different factors affect water pricing in agriculture. The water fee is the main revenue of Water User Associations (WUAs) in Turkey. Irrigation water fees have been determined by WUAs, taking into consideration crop area for gravity irrigation and volume for pump irrigation. Legal changes should be made in order to achieve sustainable WUAs immediately. Irrigation water pricing should be required to balance multiple objectives, such as economic efficiency, equity, water saving, management effectiveness and financial sustainability.  相似文献   

6.
Inadequate water resources management and a general decline in rainfall have aggravated water scarcity problems in the Upper Ewaso Ng’iro North Basin in Kenya. Furthermore, water use conflicts in the basin have escalated in recent decades due to increased competition for available water resources. Excessive abstraction of the declining river water mainly for irrigation in the Mount Kenya and Nyandarua foot zones often leads to reduced water flow during the dry seasons, greatly affecting downstream water users. Increased water use in the basin coupled with deterioration of the vegetative cover has resulted in reduced water flows in the Ewaso Ng’iro river and its major tributaries. In addition, lack of sufficient knowledge about available water resources and current lack of coordination in water resources management in the basin often result in water deficits which have hampered development in the downstream catchment. The goal of this study was to match the water requirements of various competing sectors in the basin with the available water resources in order to attain both economic and ecological sustainability. To achieve this, GIS techniques were used to quantify the spatial and temporal stream flow. The Water Evaluation and Planning (WEAP) model was applied to evaluate water resources development based on an equilibrium scenario of the current water demand. Water use was simulated for five different sectors (domestic, livestock, wildlife, irrigation and reserve). The analyses revealed that high water demand for irrigation was the main cause of excessive water abstraction particularly in the upstream catchments, giving rise to water shortages and consequently, water use conflicts downstream. The study, therefore, recommends that rainwater harvesting be promoted in the basin in order to improve water availability for productive use.  相似文献   

7.
Water managers and researchers strive towards the same objective: the improvement of the quality status of water bodies. However, there is still a gap between the results of academic studies on water systems and the information currently used in water management. The Water Framework Directive (WFD)‐Explorer, a modular toolbox which supports integrated water management in a river basin, attempts to bridge this gap. The toolbox analyses the impact of different restoration measures on river ecology based on expert rules embedded in this simulation environment. The strengths and weaknesses of the toolbox have been tested on the Zwalm River basin in Flanders, Belgium. The ecological status of streams in the basin spans the whole range of nearly pristine headwaters to severely impacted river stretches further downstream. Considering the key bottlenecks in the Zwalm basin and the user‐driven ecological status objectives, several water quality and physical habitat restoration options have been proposed to meet the European Water Framework Directive goals. The positive impact of restoration measures on the ecological quality ratio (EQR) for macroinvertebrates appeared to be the highest for measures affecting the nutrient inflows and thus chemical water body characteristics. However, the spatial scale on which the WFD‐Explorer modelled the impact of physical habitat restoration may have been too coarse to generate reliable results concerning such restoration measures. Hence, the combination of the WFD‐Explorer results with those of more detailed studies on physical habitat restoration impacts might be a promising approach to reliably support decision‐making implementation of the WFD. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

8.
Water suppliers in parts of Europe currently face occasional Drinking Water Directive compliance challenges for a number of pesticide active substances including metaldehyde, clopyralid and propyzamide. Water Framework Directive (WFD) Article 7 promotes a prevention-led (catchment management) approach to such issues. At the same time, European pesticide legislation is driving reduced active substance availability. In this context, embedding agronomic drivers of pesticide use into catchment management and regulatory decision making processes can help to ensure that water quality problems are addressed at source without imposition of disproportionate cost on either agriculture or potable water suppliers. In this study agronomist knowledge, perception and expectations of current and possible future pesticide use was assessed and the significance of this knowledge to other stakeholders involved with pesticide catchment management was evaluated. This was then used to provide insight into the possible impacts of active substance restrictions and associated adaptation options. For many arable crops, further restrictions on the range of pesticides available may cause increased use of alternatives (with potential for “pollution swapping”). However, in many cases alternatives are not available, too costly or lack a proven track record and other adaptation options may be selected which catchment managers need to be able to anticipate.  相似文献   

9.
An estimation of the crop water requirements for the Pontina Plain, Central Italy, was carried out through the use of remote sensing land classification and application of a simple water balance scheme in a GIS environment. The overall crop water demand for the 700 km2 area was estimated at about 70 Mm3 year − 1, i.e. 100 Mm3 year − 1 irrigation requirements when considering an average irrigation application efficiency of 70%. The simplest and least demanding available methodology, in terms of data and resources, was chosen. The methodology, based on remote sensing and GIS, employed only 4 Landsat ETM+ images and a few meteorological and geographical vectorial layers. The procedure allowed the elaboration of monthly maps of crop evapotranspiration. The application of a spatially distributed simple water balance model, lead to the estimation of temporal and spatial variation of crop water requirements in the study area. This study contributes to fill a gap in the knowledge on agricultural use of water resources in the area, which is essential for the implementation of a sustainable and sound water policy as required in the region for the application of the EU Water Framework Directive.  相似文献   

10.
The Jordan National Water Master Plan integrates multiple efforts to address the national water shortage, but suffers problems in implementation. The systems analysis-based approach proposed here involves stakeholders in defining: study areas/issues, flow limits (based on infrastructural, sustainability and management reasons), and the optimization objective function. The approach includes using a newly developed computer optimization model to speed analysis of stakeholder proposals. The optimization model calculates multi-period water distribution and allocation strategies, minimizing unsatisfied demand or optimizing economic effect. Implementing the approach would identify opportunities for improving water supply, conveyance and demand management, and help investment planning and international negotiations. It is transferable to other countries.  相似文献   

11.
Operation of a secondary canal was recently transferred to the farmers’ organization (FO) under irrigation management transfer (IMT) programme. After modernization of Upper Swat Canal (USC) irrigation system, the water allowance was increased to operate the irrigation system more in demand responsive mode. The study of the existing operation of the canal revealed that most of the time the irrigation supplies exceed the demand and the farmers either over irrigate their fields or waste precious irrigation water. Operation and management aspect of the irrigation system play a pivotal role in overall water management practices. SIC hydrodynamic model was employed to evaluate the operational performance of the distributary. Different operational scenarios were investigated and quantified based on fixed frequency operation. Based on these results it is suggested to operate the distributary at 80–90% of the design discharge during May to July, and 75–90% of the design discharge from August to April to reduce water losses due to high water allowance.  相似文献   

12.
In Emilia Romagna region (northern Italy), the Water Protection Plan (WPP) — a tool designed to reach the objectives of the Water Framework Directive — established different measures to achieve a good quantitative status of water bodies. The objective of this study is to evaluate the combined economic, agronomic and environmental impacts of four measures of the WPP on the “Renana” reclamation and irrigation scheme, and to quantify the water conservation in agriculture under the uncertainty of water availability. To this purpose, a mathematical stochastic model able to represent uncertainty in water availability was designed and implemented. Some data were collected from farms, and local sources were used as well to test the model. Each analyzed measure was simulated in a single scenario, and subsequently combined with other measures. The performed simulations are the following: application of volumetric water pricing (Scenario WFD1), awarding incentives for farmers to improve on-farm irrigation efficiency (Scenario WFD2a), combination of WFD1 and WFD2a (Scenario WFD2b), reduction of water abstraction in case of water shortage (Scenario WFD3a), combination of WFD1 and WFD3a (Scenario WFD3b), increasing distribution efficiency in the channel system (Scenario WFD4a) and combination of WFD1 and WFD4a (Scenario WFD4b). Results have shown that scenarios WFD2a and WFD4a generate a higher income for farmers and produce a positive ecological impact (water use and soil cover) but tend to increase total water use. Scenarios WFD1 and WFD3a have the opposite effects since they reduce farmers’ income but decrease water use as well. Only WFD1 could be favorable for the Board governing the scheme (RIB) in terms of economic returns. Finally, results have shown that combined scenarios WFD2b and WFD4b, respectively, could modify the trade-off between economic and environmental objectives and could be more effective since they significantly reduce water consumption and minimize losses in farmers’ income.  相似文献   

13.
Lake Alemaya in the Ethiopian Highlands has historically provided the surrounding area with water for domestic use, irrigation, and livestock and has served as a local fishery tank. Increasing irrigation and domestic water use, change in the local climate and changes in the surrounding land cover are believed to be the causes of Lake Alemaya’s demise. Expansion of major irrigated crops in particular chat (Catha Edulis), potato and vegetables and non-judicious use of irrigation water in the Lake Alemaya watershed led to presumption that irrigation is partly responsible for the withdrawal of large quantity of water from the lake. Thus, water balance study of Lake Alemaya was carried out under presumed scenarios in order to study the possible trends and fluctuations of the lake water level in response to proposed scenarios. Further, it is essential to study the irrigation performance for developing optimal irrigation schedules in the study area to make the best use of available water for long term sustainability of the water resources of Lake Alemaya. It was identified that expansion of the irrigated area in general and chat cultivation in particular in the study area have been the key to sustainable management of lake water, hence its expansion during the past 37 years (1965–2002) was studied through interpretation of satellite data. Subsequently, performance evaluation of the small-scale irrigation practices for major irrigated crops was carried out. Optimal irrigation schedules for different crop seasons were also developed for these irrigated crops using CROPWAT software. It was found that chat area increased from 190 ha in 1996 to nearly 330 ha in 2002. Further, it was observed that 43% surface area of the lake has reduced within a span of 37 years. Overall, maximum irrigation intensity of chat, potato and vegetables is observed during the first irrigation season of the crop calendar. Particularly, in case of chat, irrigation performance indicators such as Relative Water Supply (RWS), Relative Irrigation Supply (RIS), Depleted Fraction (DF) and Overall Consumed Ratio (OCR) values indicated poor performance of irrigation practices. From the analysis, it was found that the application of a fixed irrigation depth and fixed irrigation interval combinations of (25 mm—25 day), (20 mm—20 day), or (20 mm—25 day) are recommended for chat in the study area. Optimal irrigation schedules were decided on the basis of combination of irrigation interval and depth that results in low loss of irrigation water with reasonable yield reduction. Thus, determination of appropriate water management strategy can ensure proper utilization of the available water resources and improve the water application efficiency of the small-scale irrigation practices around Lake Alemaya, Ethiopia.  相似文献   

14.
15.
Water is a very crucial natural resource in the world and because of its selective availability among different countries; it will be the most precious commodity in the future. In the Mediterranean basin one can find a mosaic of countries rich in water and others poor. However, the common issue for all these countries is how to improve water resources management. NOSTRUM-DSS [Network on Governance, Science and Technology for Sustainable Water Resources Management in the Mediterranean. The role of DSS (Decision Support System) tools. Contract 509158. August 2004–August 2007], which is a co-ordination action funded by the European Commission under the Sixth Framework Program, aims to contribute to the achievement of improved governance and planning in the field of sustainable water management. In order to achieve this goal, DSS tools which can ease the problem of accessing information about an Integrated Water Resource Management (IWRM) for decision makers, scientific community, and other organizations must be created. An online database is one of these tools which can help in creating an IWRM. This tool can reduce information redundancy, eliminate unneeded expenses, and create regional cooperation in the area of water resources management. In this paper a new Web based meta-database about climate, remote sensing, and Geographic Information System (GIS) related to water resources management is introduced, and its role in improving water resources management is discussed.  相似文献   

16.
Integrated management of pipe networks should include methods for monitoring, repairing and replacing deteriorating components (usually pipes), but also methods and everyday operating practices towards a proactive risk assessment approach in order to give a solid answer to the unavoidable “repair or replace” dilemma. The present paper attempts to check whether the Discriminant Analysis and Classification (DAC) method can be used to achieve the above mentioned goals and predict the future behaviour of network pipes. Three pipe networks carrying different types of fluids (oil; gas; and water) are used as case studies. For each case study network, the DAC method is used to classify the pipes into two groups (failures/successes), based on simple variables (pipe/network characteristics) and dimensionless joint ones. Several scenarios are being analysed for each case. The results for the two cases of oil and gas networks are very satisfying. The implementation of the DAC method to water pipe networks needs to overcome serious problems related to the quality, reliability and compatibility of the data records provided by the Water Utilities. In this paper, these shortcomings are faced combining field data with theoretical one. Also the distinction between what “failure” and “success” actually mean in a water pipe network has to be determined. The present study uses the total water volume being lost as a definition criterion.  相似文献   

17.
Abstract

In Europe the implementation of the Water Framework Directive (WFD) will have major implications for water resources management. Part of the Directive requires Member States to implement a comprehensive system of controls (licences) on the allocation and abstraction (withdrawal) of surface and groundwater resources. This paper describes the development of a procedure to help assess and set abstraction licences for agricultural irrigation. The methodology is described with reference to Scotland, a country with limited abstraction control previously and where irrigation is supplemental to rainfall. The methodology combines spatial climatic information using a Geographical Information System (GIS) with data derived from a water balance computer model. The procedure enables the volumetric irrigation demand in a ‘design’ dry year for a given site to be estimated, taking into account local variations in climate, soil type, land use and irrigation practices. The approach provides a scientifically robust framework to allow the regulatory authority to assess the ‘reasonable’ water requirements of individual irrigators and hence develop allocations to satisfy the range of competing demands (e.g. agriculture, industry, and environment) on water resources. The methodology is applicable in other temperate countries where water abstraction controls are required and where appropriate datasets are available. The application of the procedure and its methodological limitations are described.  相似文献   

18.
Water catchments worldwide are experiencing increasing pressure on the quantity and quality of ground and surface water resources. Water managers are increasingly consulting community and stakeholder groups to ensure their decisions reflect the values and preferences of water users. Growing tensions between different water users require the use of techniques that can enable stakeholders to learn about each others’ positions and deliberate about the costs and benefits of alternative water allocation scenarios. This paper describes the use of scenario development, a small group deliberative process (citizens’ jury) and multi-criteria analysis to assist in water planning for the Howard River catchment in the Northern Territory (NT) of Australia. Water planning processes in the NT are in their infancy. As such, this research provides information about stakeholder preferences where none was previously available and demonstrates the use of a new water planning tool. The research found that the process in this case was most useful in providing information to stakeholders, dispelling some unhelpful myths about water use in the catchment, and coalescing opinion about important criteria for assessing future options.  相似文献   

19.
Abstract

Jordan is extremely water-scarce with just 167 m3 per capita per year to meet domestic, industrial, agricultural, tourism, and environmental demands. The heavy exploitation of water resources has contributed to declines in the levels of aquifers and the Dead Sea. Rapid growth in demand, particularly for higher quality water for domestic, industrial, and tourism uses, is significantly increasing pressure on agricultural and environmental uses of water, both of which must continue to adapt to reduced volumes and lower quality water. The agricultural sector has begun to respond by improving irrigation efficiency and increasing the use of recycled water. Total demand for water still exceeds renewable supplies while inadequate treatment of sewage used for irrigation creates potential environmental and health risks and presents agricultural marketing challenges that undermine the competitiveness of exports. The adaptive capability of the natural environment may already be past sustainable limits with oasis wetlands having been most seriously affected. Development of new water resources is extremely expensive in Jordan with an average investment cost of US$4 to $5 per cubic meter. This paper examines four integrated water resources management (IWRM) approaches of relevance to Jordan: water reuse, demand management, energy-water linkages, and transboundary water management. While progress in Jordan has been made, the Ministry of Water and Irrigation continues to be concerned about the acute water scarcity the country faces as well as the need to continue working with concerned stakeholders to assure future water supplies.  相似文献   

20.
The European Union Water Framework Directive (EU WFD) is a unique piece of legislation, which may be of great significance to on-going reforms of the water sector in China. First and foremost it unites 27 European member states behind a common goal, which is “to achieve good chemical and ecological status” of all water bodies across the EU. Other significant characteristics of the EU WFD are that (1) it sets a clear timeframe with a number of time-bound actions for member states to achieve the goal, but leaves it to member states to achieve this goal in a decentralised process, which makes allowance for the different socio-economic conditions, (2) it defines the river basin as the management unit for water thus departing with the traditional fragmented management by administrative units and it appoints a single competent authority for water management within each river basin, thus facilitating resolution of sector conflicts, (3) it requires a financial and economic analysis of the costs of implementing the EU WFD to enable decision makers to assess whether the required improvements are affordable to government and to the population within the river basin, and (4) it requires a structured process for information and consultation with stakeholders and the public throughout the planning and implementation process.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号