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201.
SUMMARY

A rich diversity of traditional crops occurs generally in the Himalaya and more particularly in Central Himalaya. Over forty species of food grains are grown in traditional agroecosystems of Central Himalaya, which have been managed by the local farming communities since time immemorial. These traditional crop varieties have evolved over centuries and are well adapted to the particular area. A number of edaphic, topographic and climatic factors associated with different selection pressures over centuries of cultivation resulted in immense variations in the crop species.

The grain and by-product yield of the majority of the traditional crops cultivated across an altitudinal gradient were worked out and compared with common food crops (paddy, wheat, mustard) at two points in time (1970-74, 1990–94) and it was found that almost all the traditional crops had slightly higher yields during 1970–74 than between 1990–94. However, common food crops grown during the Kharif season had higher yields during 1990–94 whereas, Rabi season crops exhibited higher yield during 1970–74. The yield of rainfed paddy remained static over the years across the altitudinal gradient. Among the traditional crops cultivated during the Kharif and Rabi seasons in mixed and pure forms at different altitudes were Macrotyloma uniforum (at higher altitude), Parilla frutescens and Vigna mungo (at middle altitude) and Panicum miliaceum (at lower altitude) which were found to be eco-energetically efficient. Avena sativa (oat) and mixed cropping of Fagopyrum esculentum and potato had higher energy efficiency ratios whereas the latter also exhibited a higher monetary output/input ratio. Crops like paddy and wheat with mustard, grown in irrigated land were found to be more eco-energetically efficient than the same crops grown in the rainfed land. In general, traditional crops possess higher nutritive value than the common food crops. The contribution of traditional crops to the local diet (kg/capita/year) and their energy and protein equivalents were higher during both time periods. It was observed that while exporting these traditional crops, the locals of the region are highly exploited by middlemen. Despite having huge potential, traditional crop diversity of this region has been reduced to a great extent during the last two decades. Besides, the area under cultivation with these crops has been declining rapidly. However, many of these crops possess immense potential to meet the growing food demand and ensure food security of an increasing population. Therefore, a comprehensive programme of conservation through various means and improvement of agronomic yield in their natural habitats is urgently needed.  相似文献   
202.
SUMMARY

Over-population in relation to poor land productivity and cultivation in less fertile lands is resulting in land degradation and deforestation in UP hills. Growing demand of more food production and increasing need for more cash in hand have forced the hill people to cultivate all kinds of land, resulting in the denudation of land resources and soil erosion. These changes resulted in out migration of the area's human resource. A new management system for the revival of natural resources and the sustainable utilization of the area's human population and livestock has been proposed, involving active local participation in order to change the existing land-use to a system based on the soil fertility scale.  相似文献   
203.
Reducing emissions from deforestation and forest degradation (REDD+) attracts poor nations to keep their forest standing only to sequester carbon through monetary incentives. However, in countries like Nepal where forest is an integral part of social practices, communities need to keep using forests for making a living. Based on household survey, field interview, personal observation, and broad review of forestry legislations, this paper scrutinizes villagers’ experiences of changes in forest management after implementation of a REDD+ pilot project in nine Community Forestry Users Groups (CFUGs) of Nepal. Since REDD+ was not initiated by local communities but tacitly implemented by international NGOs, most villagers lacked knowledge about it and the associated benefits from the pilot project, thus fewer villagers were found to be motivated to participate in the pilot project. Consequently, it delinked villagers from their forest by implicitly tightening uses rules, which resulted in constraints to fetch forest products. In addition, REDD+ benefits were distributed to some poor households but not to all, which resulted to an antagonistic sentiment in the villages. Thus, a rigorous assessment of conditions and framework of REDD+ and an involvement of local community from the start without compromising in the uses of forest products is of the utmost importance before considering the REDD+ framework as an alternative or as similar to CFUG in Nepal. Alternatively, REDD+ can be a part or a development project under the CFUG’s framework, which could be socially as well as legally acceptable on the present situation.  相似文献   
204.
The giant panda was found on Mount Shennongjia in Central China for thousands of years but vanished in the late 19th century. The possibility for reintroducing the giant panda in Shennongjia is discussed in terms of food availability, carrying capacity, and predicted bamboo flowering. Three species (Fargesia spathacea, F. murielae, and Yushania confusa) are considered the preferred forage bamboos, which could feed 193–223 giant pandas. However, in 1879–1888 these three species synchronously flowered and died back. In the past, such bamboo flowering usually forced the panda to migrate to a new habitat where forage bamboos were available. But since the 19th century, Shennongjia has become separated from other panda habitats by densely populated agricultural zones. Multi-species flowering of the forage bamboo and isolating of the habitat might caused the extinct of the giant panda in Shennongjia. If the flowering cycle of the bamboo is genetically fixed, the next synchronous flowering of two staple food species (F. spathacea and F. murielae) may occur in 2436–2439. It means that the food supply is dependable in Shennongjia for reintroducing the giant panda before 2436.  相似文献   
205.
The Central Himalayan region is suffering from severe ecological problems as a consequence of deforestation and that threatens the subsistence population of the region. We analyze this problem and propose a plan for ecologically sustainable development for the region based on an analysis of the interrelationships of various ecosystems, particularly cropland and forest ecosystems, around which most human activities are concentrated. Each energy unit of agronomic yield leads to expenditure of about 12 energy units of forest/grazing land energy. Because with rapidly declining forest area, this form of agriculture is no longer sustainable and cannot be converted into a fossil fuel-based agriculture, we propose that agriculture in the mountain region has to be largely replaced with farm forests to revitalize the environment and to generate the basic needs of the subsistence economy of the hill population whose food grain needs can be met from the plains. We conclude by describing the advantages that are likely to accrue to the people for their long-term future. In terms of both energy and money, the value of resources collected from the forest to support agriculture in the present systems far exceeds the value of food grain that would be required to enable the proposed farm forest-based systems to function. At regional level, the proposed system would generate more energy than the existing systems, not only because the productivity of forest is about tenfold greater than that of cropland, but also because the proposed plan promotes recovery of various ecosystems.  相似文献   
206.
自然中心主义环境伦理思想作为目前最为热门的学科之一,自然同其它学科一样,有它产生的思想根源、现实缘由和直接的动因。工业社会的精神失落和蓬勃兴起的绿色运动是其思想诱因与直接动因,而它形成的现实缘由则主要是全球面临的生态困境以及对人与自然关系的重新认识。  相似文献   
207.
Abstract: A discharge rating is a relationship between stage and discharge at a specific point in a river stream or lake outlet structure. Rating curves are useful for interpolating and perhaps extrapolating flow measurements and for use directly in storage routing models. However, rating data and stations are limited. A generalized nondimensional mathematical expression that describes the rating relation of depth and discharge has been developed and tested against observations from 46 stations in West‐Central Florida. Three approaches were tested in sequence to select the best fit. The proposed model is a log‐linear equation with zero intercept and a slope that fits more than 50% of the stations were analyzed. The model is normalized by the depth and discharge values at 10% exceedance from data published by the U.S. Geological Survey. For ungauged applications, Q10 and d10 were derived from a relationship shown to be reasonably well correlated to the watershed drainage area. The average relative error for this parameter set shows that for the flow range up to the Q10 discharge, better than 30% agreement with the USGS rating data can be expected for about 50% of the stations. Further analysis is required to determine why so many stations exhibit such similar behavior and to identify the criteria or parameters governing the differences.  相似文献   
208.
Remote sensing data combined with other spatially referenced data were used to predict water resource use in an irrigated area of Central Oregon. Crop type and irrigation method were determined using color infrared aerial photography and thermal infrared imagery, respectively. These data were combined with crop consumptive use and irrigation method application efficiency values to determine total water applied to a transect sample through the heart of the study area. This information, when integrated with data on canal leakage and storage reservoir seepage, allowed the researcher to predict total water use for the entire management unit. The model developed allowed the researcher to attain results accurate to within 92.0 percent of actual values, suggesting that predictive water use models which use such techniques have tremendous potential for providing water resource managers with near real-time statistics required for making wise management decisions.  相似文献   
209.
索尔库里盆地位于青藏高原东北缘,柴达木盆地的北部,气候恶劣、交通不便,研究资料匮乏。通过对索尔库里北盆地彩虹沟剖面新近纪中后期沉积物的古地磁测年和碳酸盐碳氧同位素质谱分析,揭示了索尔库里盆地13.5~2.5 Ma长序列气候演变过程。13.5~9.2 Ma时期相对冷干,9.2~5.3 Ma时期相对温湿,5.3~3.9 Ma时期相对暖湿,3.9~2.5 Ma时期再次转为冷干。11 Ma左右,青藏高原东北缘隆升到阻止印度洋暖湿气流向北方运输的高度,地处走滑盆地的索尔库里地区逐渐变得极其干旱,标志着亚洲内陆干旱化在此背景下开始。红粘土磁化率和碳氧同位素变化等证据显示,西风在本区贯穿始终,而季风的出现加剧了亚洲内陆古气候的干湿更迭,对区域及全球古气候重建具有重要意义。  相似文献   
210.
首届"东北亚中亚区域可持续发展国际论坛"在北京召开。与会专家围绕着"全球气候变化背景下东北亚和中亚区域可持续发展"主题展开充分讨论,并形成重要研究结论。来自中国、俄罗斯、蒙古国、乌兹别克斯坦和以色列等国20多个研究机构的7位科学院院士、9位研究所所长和200多位专家学者讨论认为,面对积极应对全球变化的国际态势,加强东北亚中亚可持续发展国际合作研究具有重大战略意义,并向东北亚和中亚地区各国政府和专家学者发出共同倡议。此次国际论坛对加强东北亚和中亚地区在全球变化背景下资源生态环境与可持续发展科学问题与规律的国际合作研究具有重要推动作用。  相似文献   
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