نتایج جستجو برای: water use productivity
تعداد نتایج: 2281676 فیلتر نتایج به سال:
At present and more so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the norm rather than the exception, and irrigation management will shift from emphasizing production per unit area towards maximizing the production per unit of water consumed, the water productivity. To cope with scarce supplies, deficit irrigation,...
the scarcity of irrigation water and decrease of water resources are the most important limiting factors in crop production in countries such as iran. thus, studying the optimum use of water and increasing water use efficiency are essential to the agricultural sector. the use of a low pressure hydroflume has been suggested to replace traditional surface irrigation methods. the aim of this resea...
Globally, agriculture accounts for 80-90% of all freshwater used by humans, and most of that is in crop production. In many areas, this water use is unsustainable; water supplies are also under pressure from other users and are being affected by climate change. Much effort is being made to reduce water use by crops and produce 'more crop per drop'. This paper examines water use by crops, taking...
1. The Nature of Resources 2. Major Factors Determining Resource Use 2.1 The Quest for Control 2.2 Productivity of Living Systems 2.3 The Productivity Paradigm 2.4 The Doctrine of Systemology 3. Major Factors Affecting Natural Resource Use 3.1 The Anthropic Revolution 3.2 Technology 3.3 Culture 4. Organization for Resource Use 5. Special Resources: Energy, Food, and Water 5.1 Energy as a Resour...
water and nitrogen fertilizer are two main factors of agricultural production and deficiency of each one makes reduction in the yield. deficit irrigation is one of the ways for water management in arid and semiarid areas, but it is effective on the need of nitrogen. excessive use of nitrogen will be a waste of capital and environmental pollution. in this study the interaction of water and nitro...
in order to investigate the indices of drought tolerance, correlation coefficient and path analysis at deficit irrigation and nitrogen experiment, this experiment was conducted as split plot arranged in a randomized complete block design (rcbd) with three replications during 2000-2003 for wheat at maragheh agricultural research station of dari. the treatments were included four levels of defici...
Crop-livestock systems in sub-Saharan Africa (SSA) are mostly rainfall-dependent and based on fragmented marginal lands that are vulnerable to soil erosion, drought and variable weather conditions. The threat of water scarcity in these systems is real, due to expanding demand for food and feed, climate variability and inappropriate land use (Amede et al., 2009). According to recent estimates, f...
Water use efficiency (WUE) is a key indicator to assess ecosystem adaptation to water stress. Rain use efficiency (RUE) is usually used as a proxy for WUE due to lack of transpiration data. Furthermore, RUE based on aboveground primary productivity (RUEANPP) is used to evaluate whole plant water use because root production data is often missing as well. However, it is controversial as to whethe...
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