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101.
Financing of wasteland afforestation in India   总被引:2,自引:0,他引:2  
India has vast tracts of wastelands, which have been lying barren for ages. Most such lands are physically suitable for growing trees and thus could be put to socially productive uses. However, although usually economically viable, afforestation requires massive initial investment, generally beyond the means of the landowners. Also, government budgetary allocations do not cover current needs. In this situation, institutional credit is required. The National Bank for Agriculture and Rural Development (NABARD) of India has recognized this need and has devised a number of different schemes to provide refinance facilities to individuals and organisations. Although the number of forestry schemes refinanced by NABARD has increased rapidly in the past, they currently constitute only about 1% of the total number of loans sanctioned, and only about 2% of NABARD's cumulative loan disbursement to date. In fact, since 1992, the share of afforestation schemes has declined. A number of factors have been identified as major constraints, including time-consuming and complicated procedures for accessing land; restrictions on harvesting and selling trees; delays in sanctioning and disbursement of bank credit; non-remunerative prices for tree products; and flawed public policies and programmes. This article argues that unless these constraints are overcome, NABARD will not be able to play an effective role in speeding up development programmes in the forestry sector. It further argues that most of the current constraints on institutional credit for wasteland afforestation can be removed or relaxed. Practical strategies are suggested to mobilize more funds and channel more institutional credit for wasteland afforestation in India.  相似文献   
102.
武陵山区猕猴桃产业化发展探讨   总被引:3,自引:0,他引:3  
武陵山区猕猴桃生产已显现出产业化发展的前景,但仍然存在基地规模发展、龙头企业品牌创立和市场开拓、科研单位研究开发的协调联动问题,解决的途径在于协调公司、基地农户、科研单位诸方面的利益.  相似文献   
103.
通过现场调研,运用故障树对浮头式换热器常见故障进行分析,得出浮头式换热器系统的主要故障为腐蚀导致的泄漏。从而,从设计、焊接制造、安装、操作维护等几个环节提出改进措施,为浮头式换热器的可靠性分析提供指导。  相似文献   
104.
乙炔干燥变温吸附装置安全性分析与燃爆事故预防对策   总被引:1,自引:2,他引:1  
针对乙炔变温吸附装置的燃爆事故问题,采用HAZOP方法对该装置进行安全性分析,找出存在的安全隐患,提出整改措施,指出装置发生燃爆事故的可能性;又将该装置可能发生的燃爆事故作为顶上事件,利用FTA方法进行分析,得到了装置发生燃爆事故的可能原因,制定了预防发生燃爆事故的对策。通过将HAZOP和FTA分析方法结合使用,有效地识别出乙炔装置存在的隐患,降低了装置操作的危险性,预防了燃爆事故的发生,值得推广应用。  相似文献   
105.
针对吉林省板石一矿可能发生的井下透水事故,采用事故树法进行环境风险评价,确定了事故预防重点,提出了相应的防范措施和应急预案,为矿井的建设和管理提供科学依据。  相似文献   
106.
The objective of this study was to determine the concentrations of Cu, Cd, Pb, Mn, Cr, Co, Ni, Zn, and Hg in the white and fruit parts of commercially available yogurts (n = 30) from Nitra markets (Slovak Republic). The results were correlated to determine their relationships. Three yogurt fruit flavors were chosen and tested, strawberry (n = 10), blueberry (n = 10), and cherry (n = 10). The elements were analyzed using atomic absorption spectrophotometry. Higher concentrations of toxic elements, such as Cd and Pb, were found in the fruit parts of the yogurt, and in some cases, the tolerable limit was exceeded. The white part of the yogurt was not contaminated by toxic elements. White yogurt is a good source of nutrients for humans, but the fruit part in yogurt requires detailed monitoring and improvements in the processing techniques.  相似文献   
107.
Aluminum concentrations in the fruit samples taken from different regions were determined by atomic absorption spectrometry after dry ashing digestion. To identify the aluminum phases being most responsible for fruit-available aluminum, the soil samples near the fruit plants were also analyzed for aluminum by using various digestion and selective extraction reagents. The relation between the aluminum concentrations in fruits and in soil extracts was studied. The obtained aluminum concentrations in the fruits were in the range of 1.5 to 42.0 mg kg-1 on dry weight basis. It was observed that the aluminum concentrations of morello cherry(R2 = 0.79) and mulberry (R2 = 0.99) were correlated to the aluminum concentrations in citric acid extracts of the soils. While the aluminum concentrations of the EDTA and acetic acid extracts in some soils samples include 35% and 25% of total aluminum, respectively, the other soils contain only 1–2%.  相似文献   
108.
四种岭南水果种植系统的能值、经济与土壤整合分析   总被引:2,自引:0,他引:2  
综合运用能值、经济与土壤生态学分析方法,定量研究了番石榴(Psidium guajava Linn)、黄皮(Clausena lansium Skeels)、枇杷(Eriobotrya japonica Lindl)、葡萄柚(Citrus paradisi Maef)4种岭南水果种植系统的物质流、能最流和货币流,综合分析其自然资源基础、经济发展状况及可持续发展程度,并将土壤有机质的消耗纳入不可更新自然资源能值投人分析,为岭南水果业的可持续发展提供科学依据.能值分析表明,4个水果种植系统的可持续发展能力依次为:葡萄柚(0.94)>枇杷(0.15)>番石榴(0.14)>黄皮(0.10).土壤有机质分布与变化分析表明,4种水果种植系统的土壤有机质消耗量依次为:葡萄柚>黄皮>枇杷>番石榴.经济分析表明,4个水果种植系统的经济效益依次为:葡萄柚>番石榴>枇杷>黄皮.综合分析表明,番石榴、黄皮、枇杷三个系统的水果生产效率有待进一步提高;葡萄柚种植系统的水果生产效率、可持续发展能力和经济效益较高,但其对土壤有机质的消耗强度在四个系统中是最高的,这一点在水土流失严重的丘陵地区显然是不容忽视的.同时,如何降低系统在市场交换中的交换性资产流失是四个系统共同面对的问题.  相似文献   
109.
遗传算法是一类借鉴自然界生物种群“自然选择、优胜劣汰”进化过程的启发式随机搜索优化算法,具通用性好、鲁棒性强等特点,被广泛地应用于通信网络设计领域,如度约束最小生成树问题.通过讨论遗传算法在度约束最小生成树问题中的应用,并对遗传算法在应用时存在的问题和挑战提出了见解.参17.  相似文献   
110.
Transfer factors are the most important parameters required for mathematical modeling used for environmental impact assessment of radioactive contamination in the environment. In this paper soil to leaf transfer factor for the radionuclides 40K, 226Ra, 137Cs and 90Sr is estimated for Kaiga region in Karnataka state, India. Among the plants in which study is carried out, 226Ra, 40K, 137Cs and 90Sr activity in leaves of herbaceous plants is higher than that of tree leaves. Soil to leaf transfer factor for 226Ra, 40K, 137Cs and 90Sr was found to be in the range of 0.03-0.65, 0.32-8.04, 0.05-3.03 and 0.42-2.67 respectively.  相似文献   
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