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41.
Groundwater governance through electricity supply management: Assessing an innovative intervention in Gujarat, western India 总被引:1,自引:0,他引:1
Gujarat, a rapidly industrializing state in western India, is notorious for groundwater over-exploitation. A perverse link between energy subsidies and groundwater overdraft has left the state with a bankrupt electricity utility and depleted aquifers, especially since the late 1980s. Moreover, this perverse relationship has meant that groundwater irrigators have essentially held Gujarat's non-farm rural economy to ransom. Efforts to regulate groundwater overdraft since the early 1970s have been unsuccessful, as have attempts to charge a rational electricity tariff to groundwater irrigators. During 2003-2006, drawing upon a proposal outlined by researchers, the government launched the Jyotigram (lighted village) scheme, which invested US$ 290 million to separate agricultural electricity feeders from non-agricultural ones, and established a tight regimen for farm power rationing in the countryside. By 2006, Gujarat covered almost all of its 18,000 villages under the Jyotigram scheme of rationalized power supply. With this, two major changes have occurred: (a) villages receive 24 h three-phase power supply for domestic uses, in schools, hospitals, village industries, all subject to metered tariff; (b) tubewell owners receive 8 h/day of power of full voltage and on a pre-announced schedule. The Jyotigram scheme has radically improved the quality of village life, spurred non-farm economic enterprises, halved the power subsidy to agriculture, and reduced groundwater overdraft. It has also produced positive and negative impacts on medium and large farmers, while notably harming marginal farmers and the landless, who depend for their access to irrigation on water markets which have become much smaller, post-Jyotigram. In addition, the water prices charged by tubewell owners have increased by 30-50%. We propose that the Jyotigram scheme, with some refinements, can be implemented successfully in other regions of South Asia facing similar challenges of groundwater governance. 相似文献
42.
我国油菜根肿病发病面积在66.7万公顷左右,约占总生产面积的10%,已严重威胁到油菜的安全生产。基于此,本研究以含有CRb抗根肿病位点的大白菜材料CR Shinki为供体亲本,以甘蓝型油菜国审杂交种华油杂62的父本Pol.CMS恢复系Bing409为受体亲本,通过杂交、回交及自交等育种程序,结合前景和遗传背景筛选,将CRb抗病位点导入到Bing409中。在BC3F2代获得了遗传背景高度接近Bing409且含CRb抗病位点的抗根肿病新恢复系Bing409R,进而成功选育了我国首个抗根肿病杂交油菜新品种华油杂62R。CRb抗病位点在甘蓝型油菜背景中表现为单基因显性遗传,根肿病抗性遗传改良的同时并未对Bing409R及由其配制的杂交种华油杂62R的产量、品质造成不良影响,Bing409R及华油杂62R对我国四川、湖北、安徽等地区根肿菌生理小种具有免疫抗性。本研究的开展为我国油菜抗根肿病育种提供了宝贵资源,为我国抵抗油菜根肿病的威胁提供了重要保障。 相似文献
43.
Ritesh Shah 《Asia Pacific viewpoint》2014,55(3):262-276
The democratic evaluative tradition has sought to change evaluation practice towards approaches and techniques that generate diverse forms of knowledge and foster public deliberation over a programme's merit and worth. This paper locates one evaluation method, ‘Most Significant Change’ (MSC), within this tradition. Drawing on two different evaluations – one, of a comprehensive economic sector assistance package to the Government of Tokelau, and the other of a psychosocial and academic support intervention for pre‐adolescent children in conflict‐affected regions of the Gaza Strip – the paper provides evidence of how MSC can capture unexpected outcomes, act as a tool for real‐time formative learning, and expose the competing theories, logics and values behind programme activity. The examples within the paper also provide evidence of how MSC begins to redistribute traditional power relationships in assessing the merit and worth of observed impacts by increasing the legitimacy of local programme knowledge, and engaging all parties in evaluative decisions. By doing so, MSC, the paper argues, better serves the purposes of learning, improvement and mutual accountability which should sit at the core of good development practice. 相似文献
44.
45.
Xiao Wang Ibrahim Mohamed Maha Ali Mohamed H. H. Abbas Ghulam Mustafa Shah Fang Chen 《植物养料与土壤学杂志》2019,182(1):72-81
A rhizobox experiment was conducted to compare the differences of soil potassium (K) distribution and absorption between two cotton (Gossypium hirsutum L.) genotypes under drought and K‐deficit conditions. Treatments included two levels of water (drought and optimum soil moisture: 25% and 35% volumetric water content) and K fertilizer rates (0 and 0.48 g potash kg?1 soil) applied to two cotton genotypes (namely HEG and LEG). Both the genotypes showed significant differences in total K accumulation without exogenous K addition. After absorption, soil content of the readily available potassium (RAK) decreased rapidly. This promoted the conversion of the mineral K into slowly available potassium (SAK). Drought significantly decreased the cotton growth and K use efficiency, and thereby reduced the effect of K fertilizer. Consequantly, the contents of RAK and SAK were greatly increased. However, K bioavailability was decreased under water stress conditions. Differences in root parameters and soil microorganisms between two cotton genotypes were significantly increased and had marked relations with available soil K contents. This study provides important information for understanding the mechanism of K use efficiency, especially under water and K stress. 相似文献
46.
Shardendu KUMAR Garima KAUSHIK Mohd Ashraf DAR Surendra NIMESH Ulrico Javier LPEZ-CHUKEN Juan Francisco VILLARREAL-CHIU 《土壤圈》2018,28(2):190-208
Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture,household,and public health sectors and,hence,are extensively distributed throughout most ecosystems.Currently,organophosphate pesticides are the most commercially favored group of pesticides,with large application areas all over the world.Depending on their fate,these organophosphorus compounds may become bioavailable for microbial degradation.Environmental microbes,such as Aspergillus,Pseudomonas,Chlorella,and Arthrobacter,are capable of coupling a variety of physical and biochemical mechanisms for the degradation of organophosphate pesticides,including adsorption,hydrolysis of P–O alkyl and aryl bonds,photodegradation,and enzymatic mineralization.Enzymes,such as esterase,diisopropyl fluorophosphatase,phosphotriesterase,somanase,parathion hydrolase,and paraoxonase,have been isolated from microbes to study and understand the catabolic pathways involved in the biotransformation of these xenobiotic compounds.This review highlights various aspects of biodegradation of organophosphate pesticides along with biological and molecular characterization of some organophosphate pesticide-degrading bacteria. 相似文献
47.
Peter Oko Ogbaji Jianmin Li Xuzhang Xue Mohamad Hesam Shahrajabian Anthony Egrinya Eneji 《Communications in Soil Science and Plant Analysis》2018,49(3):286-290
Studies were conducted to investigate mineralogical and textural characteristics of Hancheng soils in relation to fertility status, mineralogical, and particle size distribution properties, which were determined from soil samples of the profile pits in 2014. Prepared representative clay fraction samples were subjected to x-ray diffraction analysis for mineralogical characterization. The results show dominant of quartz, attributed to high granitic parent materials with a range of 65.7–84.6% mean 54.1%, moganite 59.8%, albite 12.0–26.3% mean 21.03%, flusston 18.1%, calcium magnesium silicate 10.6%, muscovite 7.8%, olivine 1.8%, and illite 1.6% were detected. The particle size distribution analysis revealed sand fraction of 28.12–30.12% mean 29.1%, 22.12–28.12% mean 25.1%; silt 34.0–36.0% mean 35%, 32.0–38.0% mean 35%; and clay 35.9–35.9% mean 35.9%, 35.9–43.9% mean 32.6% surface and subsurface soils respectively. Texture classes of the soils were clay loam to clay apredominantly clay loam. The mineralogical and textural characteristics are important in relation to soil fertility, which allow farmers to adapt crop management practices with real soil situation. 相似文献
48.
Fayaz Humara Mir Asma Hamid Tyagi Sandhya Wani Aijaz A. Jan Nelofar Yasin Mohammad Mir Javid Iqbal Mondal Biswajit Khan Mohd Anwar Mir Reyazul Rouf 《Genetic Resources and Crop Evolution》2022,69(3):1193-1205
Genetic Resources and Crop Evolution - Cicer arietinum L. (chickpea) is one of the most significant legume crops domesticated in the Fertile Crescent. This study was aimed to characterize a diverse... 相似文献
49.
Hafiz Mohkum Hammad Abdul Khaliq Farhat Abbas Wajid Farhad Shah Fahad Muhammad Aslam 《Communications in Soil Science and Plant Analysis》2020,51(10):1406-1422
ABSTRACT Organic amendments in the soil perform better than synthetic fertilizers in regards to soil fertility and sustainable crop productivity. Experiments were conducted to compare the effects of organic and synthetic fertilizers on soil fertility and wheat (Triticum aestivum L.) productivity. Soil fertility and protein contents of wheat grains (13.2% and 13.3% during 2005–06 and 2006–07, respectively) were improved by organic amendments. However, synthetic fertilizer (at the rate of 150, 100, and 60 kg ha?1 N, P2O5, and K2O, respectively) applications resulted in the maximum grain yield (4.05 and 4.46 t ha?1 during 2005–06 and 2006–07, respectively). The observed and simulated soil organic carbon (SOC) reasonably agreed during RothC model validation (R 2 = 0.99). Economic analysis showed the maximum net profit and relative increase in income ($729 US ha?1 and 309%, respectively) from inorganic treatment. Application of synthetic fertilizers increased grain yield and farm profit while organic manure enhanced grain quality. The RothC model had potential for determining the SOC in organic farming under arid environment. 相似文献
50.
Erosion is a natural geomorphic process occurring continually over the Earth's surface and it largely depends on topography, vegetation, soil and climatic variables, and therefore, exhibits pronounced spatial variability due to catchment heterogeneity and climatic variation. This problem can be circumvented by discretizing the catchment into approximately homogeneous sub‐areas using GIS. In this study, the remote sensing and GIS techniques (through Imagine®8.6 and ArcGIS®9.1 software) were used for derivation of spatial information, catchment discretization, data processing etc. for the Himalayan Chaukhutia watershed (India). Various thematic layers for different factors of USLE were generated and overlaid to compute spatially distributed gross soil erosion maps for the watershed using 18‐year rainfall data. The concept of transport limited accumulation was formulated and used in ArcGIS® for generating the transport capacity maps. Using these maps, the gross soil erosion was routed to the catchment outlet using hydrological drainage paths, for derivation of transport capacity limited sediment outflow maps. These maps depict the amount of sediment rate from a particular grid in spatial domain and the pixel value of the outlet grid indicates the sediment yield at the outlet of the watershed. Up on testing, the proposed method simulated the annual sediment yield with less than ±40% error. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献