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Hassen Abubeker Talore Deribe Gemiyo Tesfamariam Eyob Habte Friend Michael Andrew Mpanza Thamsanqa Doctor Empire 《Regional Environmental Change》2017,17(6):1713-1724
Regional Environmental Change - This paper summarizes effects of forage-legume intercropping on grain and fodder yield, land equivalent ratio, residual soil fertility, disease and insect pest... 相似文献
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Efficiency in the use of water for irrigation is normally defined in a physical sense - engineering and agronomic; and it is often assumed that higher efficiency is desirable. However, in an economic sense, there is an optimum range in the level of physical efficiency. Normally it can be said that as water prices increase, it becomes more rational to increase physical efficiency by selecting and adopting improved methods of controlling, measuring and applying water, and to design systems of pricing and regulations that will promote optimal allocation and efficient use. However, the value of water is often extremely low, in which case there may be little economic incentive to improve physical efficiency unless forced by physical factors that affect production and productivity such as soil characteristics, waterlogging or nutrient leaching.
The combination of regulations and prices that are used to allocate irrigation water reflect the conflicting goals of redistribution of income in favor of agriculture and needs to encourage efficient use of water. Regulations and pricing systems also depend on the value of water, the dependability of supplies, systems of delivery and the extent to which flows can be regulated.
Using examples and case studies, this paper discusses physical and economic efficiencies and their interrelationships. It emphasizes the role of pricing and regulations and provides general guidelines. 相似文献
The combination of regulations and prices that are used to allocate irrigation water reflect the conflicting goals of redistribution of income in favor of agriculture and needs to encourage efficient use of water. Regulations and pricing systems also depend on the value of water, the dependability of supplies, systems of delivery and the extent to which flows can be regulated.
Using examples and case studies, this paper discusses physical and economic efficiencies and their interrelationships. It emphasizes the role of pricing and regulations and provides general guidelines. 相似文献
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Yemane Wolde-Rufael Eyob Mulat Weldemeskel 《International Journal of Green Energy》2020,17(10):568-582
ABSTRACT The aim of this paper is to investigate the relationship between environmental policy stringency and CO2 emissions in BRIICTS (Brazil, Russia, India, Indonesia, China, Turkey and South Africa) for the period 1993–2014 after controlling for renewable energy, fossil energy, oil prices and income. We believe that this is the first attempt to use the recently OECD-developed environmental policy stringency index to test the effectiveness of environmental stringency policy in reducing CO2 emission in these countries. Applying the Panel Pooled Mean Group Autoregressive Distributive Lag (PMG-ARDL) estimator, we found an inverted U–shaped relationship between environmental policy stringency and CO2 emissions. This suggests that initially strict stringent environmental policy does not lead to improvements in the environment but after a certain level or a threshold point, environmental stringency policy leads to improvement in environmental quality. Renewable energy consumption was negatively related to CO2 emissions while fossil energy consumption and real oil prices and income were positively and significantly related to CO2. Our findings suggest that strengthening the stringency of environmental policies and promoting renewable energy are effective ways of preventing environmental degradation in BRIICTS countries. 相似文献
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