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Food and water scenarios for the Karkheh River Basin, Iran النص الكامل
2014
w. loiskandl | s. marjanizadeh | charlotte de fraiture
S. Marjanizadeh, Charlotte de Fraiture, W. Loiskandl, 'Food and water scenarios for the Karkheh River Basin, Iran', 2014 | Increasing population and income and a wheat self-sufficiency policy are already stressing Iran's strategic Karkeh River Basin. Examining three scenarios to the year 2025, the authors of this study find: (1) business as usual leads to an aggravation of groundwater overdraft and may jeopardize the ecosystem services provided by the Hawr Al Azim marsh area; (2) giving priority to environmental flow requirements and restoring groundwater tables leads to a shortfall in wheat production; but (3) reducing agricultural water demand could maintain a certain level of food production. Appropriate policy could minimize the tradeoffs between food self-sufficiency, sustainable water use and farmers' income
اظهر المزيد [+] اقل [-]Growing more food with less water: how can revitalizing Asia's irrigation help? النص الكامل
2014
aditi mukherji | s david | colin j. chartres | t. facon | charlotte de fraiture
Asia accounts for 70% of the world's irrigated area and is home to some of the oldest and largest irrigation schemes. While these irrigation schemes played an important role in ensuring food security for billions of people in the past, their current state of affairs leaves much to be desired. This paper takes forward the IWMI-FAO-ADB (Asian Development Bank) recommendation of a five pronged approach for revitalizing Asia's irrigation and provides a region specific road map for doing this. The underlying principle of these multiple strategies is the belief that the public institutions at the heart of irrigation management in Asia need to give up comfortable rigidity and engage with individual users' needs and the demands placed by larger societal chang | Aditi Mukherji et al., 'Growing more food with less water: how can revitalizing Asia's irrigation help?', 2014
اظهر المزيد [+] اقل [-]Growing more food with less water: how can revitalizing Asia?s irrigation help? النص الكامل
2014
colin j. chartres | aditi mukherji | s david | t. facon
Aditi Mukherji, T. Facon, S David, Colin J. Chartres, 'Growing more food with less water: how can revitalizing Asia?s irrigation help?', 2014 | Irrigation has always played a central role in the agrarian economy of Asia, from supporting famed hydraulic civilizations in the ancient past to spearheading Green Revolution in the 1960s and 1970s,. Asia accounts for 70% of the world?s irrigated area and is home to some of the oldest and largest irrigation schemes. While these irrigation schemes played an important role in ensuring food security for billions of people in the past, their current state of affairs leaves much to be desired. The purpose of this paper is analyze the current trends in irrigation in Asia and suggest ways and means for revitalizing irrigation for meeting our future food needs and fuelling agricultural growth. The paper recommends a five pronged approach for revitalizing Asia?s irrigation and provides region specific strategies for the same. The underlying principal of these multiple strategies is the belief that the public institutions at the heart of irrigation management in Asia need to give up comfortable rigidity and engage with individual users? needs and the demands placed by larger societal changes
اظهر المزيد [+] اقل [-]Effect of transboundary water agreements on water and food security of downstream riparian communities: a case study of Indus Waters Treaty النص الكامل
2014
waqas ahmad | sarfraz munir | asghar hussain
Sarfraz Munir, Waqas Ahmad, Asghar Hussain, 'Effect of transboundary water agreements on water and food security of downstream riparian communities: a case study of Indus Waters Treaty', 2014 | Transboundary water conflicts are awfully crucial in their nature as they not only endanger the food and water security of the riparian communities but also jeopardize the security and existence of the conflicting nations. Any inappropriate action done by upper riparians directly affects the existence of lower riparians. Therefore they need special care to be dealt with. There are 261 international rivers, covering almost one-half of the total land surface which are shared between two or more nations. The management of international waters has been poorly defined in the international arena. In 1947, after the independence of subcontinent, the Indus Basin was divided into two parts between India and Pakistan. Soon after independence India started to halt the river supplies to Pakistan and closed all supplies to the canals which were crossing the India-Pakistan border. India agreed to restore some of the supplies to Pakistan in May 1948, when quite a pro-Indian temporary agreement was signed. It was, however, generally realized that Pakistan could not live without restoration of the full supplies and on this question there could be no compromise. Direct negotiations between the parties failed to resolve the dispute. Negotiations under the World Bank commenced in May 1952. The World Bank planned to divide Indus Basin Rivers into two parts the eastern rivers, under completely Indian control and the western rivers for unrestricted use by Pakistan. Pakistan was not fully convinced and refused to sign until 1958 but ultimately the Treaty was formalized in 1960 after some necessary modifications. Pakistan, on one hand, was deprived a substantial amount of its waters in the Indus Waters Treaty, but on the other, it also got the right of unrestricted use of western rivers. Pakistan also received some assistance (grants and loans) from the World Bank for construction of replacement works for some water storage and diversions. It is evident that the closure or diversion of river flows in the upstream reaches not only affect the downstream river ecology but also puts the downstream irrigated agriculture at stake. This paper highlights the effects of the IWT on water availability and irrigated agriculture in Pakistan. Study finds that though there are some deprivations of surface waters availability to the Pakistan under the IWT but at the same time there are also some improvements in canal water diversions, which are mainly due to the construction of water storage reservoirs. An increase in the cropped area and crop production also has been observed which owes to many other social, economical and technical factors but all this was not possible without reliable irrigation water supplies
اظهر المزيد [+] اقل [-]Spatio-temporal changes in water-related ecosystem services provision and trade-offs with food production النص الكامل
2021
Yang, Shiliang | Bai, Yang | Alatalo, Juha M. | Wang, Huimin | Jiang, Bo | Liu, Gang | Chen, Junyu
A key challenge for sustainability is protecting water-related ecosystems and the services (WESs) they provide while enhancing food security. Food production usually drives land use change, which results in ecosystem services provision being altered. However, the underlying mechanisms are still unclear and relevant research is scarce. In this study, a spatio-temporal assessment framework was developed to assess the impact of food production-driven land use change on WESs and to analyze tradeoffs between food production and WESs provision, taking Songhua River Basin (SRB) as a case study. The results showed that: 1) food production increased from 0.497×108tons to 0.798×108tons despite area of cultivated land decreasing from 23.61×104km2 to 23.40×104km2 during the study period (2000–2015). 2) Water yield and soil retention both showed a downward trend, while nitrogen and phosphorus exports showed an increasing trend, in 2000–2015.3) Food production showed a trade-off relationship with soil retention and water yield, but a synergistic relationship with nitrogen and phosphorus export. This is important empirical evidence of the impact of food production-driven land use change on WESs. For simultaneous development of food production and WESs, a form of sustainable agricultural production must be established, with intensification of existing land use and establishment of farmland shelterbelts. This critical knowledge can be applied in developing practical ecosystem protection measures and land management strategies for food security in China and beyond.
اظهر المزيد [+] اقل [-]Managing Scarce Water Resources in Irrigated Agri-Food Systems of Central Asia Two Case Studies النص الكامل
2017
Irrigated agriculture is the backbone of Central Asian economies. Therefore, efficient irrigation water management is of crucial importance to the sustainable crop production in the region. Presented here are two studies aiming to improve agricultural water productivity â?? ET-based irrigation scheduling in Uzbekistan; and valuation of ecosystem services in Kazakhstan. The ET-based irrigation scheduling method has potential to replace subjective daily water management decisions at Water Users Association level with crop water demand-based decisions to improve water-use efficiency. Results from a two year study show that there can be a 32-35% saving of water when irrigation is applied using the ET-based scheduling method. The pilot plots are representative of 38% of irrigated area in Fergana Valley (241,407ha) and 50% in Khorezm (137,500ha) area. If this methodology is widely adopted, large amounts of water can be saved which can be diverted for other purposes. Flood irrigation of cotton is practiced on 128,000ha in the Bugunski Reservoir watershed of Kazakhstan. This practice is unsustainable due to seasonal unavailability in water supply and depletion of river discharges that were historically important at maintaining water levels downstream in nearby wetlands and the Aral Sea. Farmer surveys were used along with RIOS and SWAT modeling to evaluate alternative irrigation practices and cropping systems that can conserve water from the Bugunski Reservoir while maintaining farmer incomes. Simulations show significant reductions in irrigation water demand in the alternative scenario relative to the baseline scenario. Under baseline flood irrigation of cotton, annual irrigation demand was 928 MCM/yr averaged over the 32 year climatic record simulated. Irrigation demand decreased by 38% to 573 MCM/yr when 40,439ha of flood irrigated cotton was converted to drip irrigated cotton, sprinkler irrigated alfalfa and drip irrigated grapes. This represents a savings of 355 MCM/yr in water extracted from irrigation canals and groundwater wells | Vinay Nangia. (7/11/2016). Managing Scarce Water Resources in Irrigated Agri-Food Systems of Central Asia Two Case Studies. Phoenix, United States: American Society of Agronomy.
اظهر المزيد [+] اقل [-]A participatory methodology for characterizing and prescribing water-energy-food nexus based on improved casual loop diagrams النص الكامل
2021
Zhang, Tong | Tan, Qian | Zhang, Shan | Zhang, Tianyuan | Zhang, Weijia
As the basis of quantitative research over water-energy-food nexus (WEFN), qualitative analysis is indispensable for depicting the systems and providing effective measures and policies. Preceding qualitative WEFN studies largely neglected the role of local stakeholder participation, which could only reflect fragments of the systems. Causal loop diagrams (CLDs) have been proven to be effective for supporting stakeholder participation in many other areas. Nevertheless, there was a lack of impartial methods that could make CLD analysis tractable without significantly impairing the WEFN systems integrity. To fill such gaps, a novel method based on merging and reduction rules was proposed to reasonably merge and downscale WEFN CLDs built by stakeholders. Based on this improved method, a CLD-based methodology was developed as a prototype for characterizing WEFN systems, prescribing the WEFN problem, exploring its causes and consequences, and identifying effective measures and policies for alleviating conflicts. To validate the applicability of the developed methodology, it was applied to a real case. The results indicated that total water consumption, water allocation among varied sectors, available surface water, and available groundwater, as well as indirect factors such as volume of diverted water and agricultural water consumption, were the keys to alleviate water scarcity problem under WEFN in the study area. Measures and polices focusing on the interactions between surface water and groundwater could be viable for alleviating the problem. Directions to enhance tradeoffs and synergies within WEFN systems were also obtained.
اظهر المزيد [+] اقل [-]Water productivity and poverty in the transboundary river basin of India and Bangladesh: a situation analysis. Project report submitted to IUCN under the project "Water Productivity, Poverty and Food Security? النص الكامل
2014
upali a. amarasinghe | bharat r. sharma
For decades, increasing land productivity was a major driver of improving food security and reducing rural poverty. However, with increasing water scarcities, competing water demand across different sectors, and increasing cost of investments in water resources development require a paradigm shift. Improving the productivity of water use is emerging as a new way of addressing water scarcity while reducing vulnerability and improving income. Increasing both physical and economic water productivities (quantity per drop and value per drop) are central to this approach. The extent to which physical and economic water productivity should be improved is and area and context specific. However, the approach is especially important in areas that are populated with large agriculturally dependent small-holder rural people and areas that experience recurrent droughts and floods and lack access to proper infrastructure. A major part of the Ganga-Brahamaputra-Meghna (MBG) river basins have such characteristics. This report examines the current situation of poverty, food security and water productivity and their linkages and knowledge gaps in the MBG basins | Upali A. Amarasinghe, Bharat R. Sharma, 'Water productivity and poverty in the transboundary river basin of India and Bangladesh: a situation analysis. Project report submitted to IUCN under the project "Water Productivity, Poverty and Food Security?', International Water Management Institute (IWMI), 2014
اظهر المزيد [+] اقل [-]Understanding and conceptualizing how urban green and blue infrastructure affects the food, water, and energy nexus: A synthesis of the literature النص الكامل
2021
Bellezoni, Rodrigo A. | Meng, Fanxin | He, Pan | Seto, Karen C.
The interactive dynamics in the food, water, and energy system as a nexus (FWEN) are critical to the sustainable development of global cities, and they can be mediated by green and blue infrastructure (GBI) in the urban area. Here we provide a comprehensive literature review to examine how GBI affects FWEN in urban centers, an area which is currently understudied. In order to do this, we undertake a systematic review of the literature using a meta-analytic approach and topic modelling. Based on our synthesis, we develop a conceptual framework of the key links between urban GBI and FWEN and the direction and magnitude of the relationship. We found that GBIs can benefit food supply, energy saving, and climate change mitigation but at a price of food safety and water contamination. Well-designed urban construction can help curb the negative effects. Therefore, we need to make deliberate and integrative policy to link GBI with each element in urban FWEN. Moreover, the focus of studies on GBIFWEN links is also heterogeneous across cities: urban agriculture and food security are priorities in cities located in Africa and Asia as well as in lower income and larger cities (but not metropolitan areas), while the cooling effect of green space has been a focus for cities of middle or high income. Finally, current research focuses on isolated analysis, lacking integrated studies needed for decision making supporting tools. While isolated analyses lead to connectivity failures and can result in adverse impacts, integrated analyses can identify interdependencies of environmental resources between parts of a cycle and across different scales, which can increase resource efficiency and minimize environmental degradation. Therefore, our key findings point out the importance of linking the effects of GBI on each component of FWEN in both research and policy making.
اظهر المزيد [+] اقل [-]Analysis of Nitrate Pollution Pathways on a Vulnerable Agricultural Plain in Slovenia: Taking the Local Approach to Balance Ecosystem Services of Food and Water النص الكامل
2020
Curk, Miha | Glavan, Matjaž | Pintar, Marina
Groundwater pollution with nitrate of agricultural origin is a major problem in many countries. A great deal of effort is focused on finding ways to reduce leaching from agricultural land. In this study, different land management scenarios were evaluated with the SWAT model in order to determine which are the most effective in reducing nitrate leaching on specific soil types in the Krška kotlina alluvial plain (Slovenia). The area is very important both for agriculture production and drinking water resources. The model was calibrated for three soil moisture field trial sites, each representing one major soil type of the area. Simulated soil moisture values were in good agreement with the observed values (PBIAS (percent bias) ±25%). Of the nine land management scenarios that were evaluated, vegetable rotation caused the most nitrate leaching on all soil types, but it fared better on Cambisol than on Fluvisol. Orchards on the other hand leached the least amount of nitrate, but also fared better on Cambisol. Presented studies should be considered as a preliminary stage in the study of nitrate pollution in the investigated area. Results show that nitrate leaching varies for different land management scenarios on different soil types. Further work should concentrate on field trials to evaluate the impacts of reduced fertilization on nitrate leaching and both crop yield and quality on different soil types.
اظهر المزيد [+] اقل [-]