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遥感与地理信息系统对资源利用热点地区的初步应用———以印度北部山地小流域为例 被引量:1
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作者 杨雪飞 许建初 +2 位作者 p.k.joshi P.S.Roy K.K.Das 《自然资源学报》 CSSCI CSCD 北大核心 2003年第3期368-374,共7页
资源利用与资源退化在时间及空间领域上的表现有所分异。识别出那些受人为干扰严重且易于发生资源退化的区域(资源利用的热点地区),对这些区域给予重视并采取特殊的管理机制以避免资源的进一步退化和环境的恶化,对资源的可持续利用具有... 资源利用与资源退化在时间及空间领域上的表现有所分异。识别出那些受人为干扰严重且易于发生资源退化的区域(资源利用的热点地区),对这些区域给予重视并采取特殊的管理机制以避免资源的进一步退化和环境的恶化,对资源的可持续利用具有重要的现实意义。论文以印度北部山地小流域的研究为例,根据当地实际情况,选取4个参数作为评价指标,即资源利用的重要性、资源的需求程度、资源利用的可获取性以及人类活动造成的景观生态学的干扰指数,利用遥感技术和地理信息系统对资源利用热点地区的识别进行了初步探讨。通过研究,将该流域划分为3种区域,即高度敏感区、中度敏感区和低敏感区,分别体现了不同的资源退化在空间上的分布。 展开更多
关键词 遥感与地理信息系统 资源利用 资源退化 流域划分 山地小流域 评价指标
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应用遥感技术研究土地利用土地覆盖变化及其对土壤侵蚀过程的影响——以印度北部PaliGad山地流域为例 被引量:1
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作者 李巧宏 许建初 +1 位作者 p.k.joshi Nikhil LELE 《云南植物研究》 CSCD 北大核心 2006年第2期175-182,共8页
应用遥感技术评估了印度北部PaliGad山地流域过去几十年里土地利用土地覆盖变化及其造成的土壤侵蚀程度,并基于摩根参数模型(Morgan Parametric Model)的方法来测定土壤的侵蚀程度;结果表明,由于不同的坡向受到太阳光照的不同可以引起... 应用遥感技术评估了印度北部PaliGad山地流域过去几十年里土地利用土地覆盖变化及其造成的土壤侵蚀程度,并基于摩根参数模型(Morgan Parametric Model)的方法来测定土壤的侵蚀程度;结果表明,由于不同的坡向受到太阳光照的不同可以引起土地覆盖的变迁;海拔和坡度已不再是阻碍人们获取自然资源的因素,人们的活动范围正转移到更高的海拔和更陡峭的坡度;揭示了土地利用土地覆盖变化对土壤侵蚀进程有着直接的影响。 展开更多
关键词 遥感 地理信息系统 喜马拉雅西部 土地利用/土地覆盖变化 土壤侵蚀
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Snow Cover Variation and Streamflow Simulation in a Snow-fed River Basin of the Northwest Himalaya 被引量:5
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作者 Vaibhav SHARMA V.D.MISHRA p.k.joshi 《Journal of Mountain Science》 SCIE CSCD 2012年第6期853-868,共16页
Snowmelt is an important component of any snow-fed river system.The Jhelum River is one such transnational mountain river flowing through India and Pakistan.The basin is minimally glacierized and its discharge is larg... Snowmelt is an important component of any snow-fed river system.The Jhelum River is one such transnational mountain river flowing through India and Pakistan.The basin is minimally glacierized and its discharge is largely governed by seasonal snow cover and snowmelt.Therefore,accurate estimation of seasonal snow cover dynamics and snowmeltinduced runoff is important for sustainable water resource management in the region.The present study looks into spatio-temporal variations of snow cover for past decade and stream flow simulation in the Jhelum River basin.Snow cover extent(SCE) was estimated using MODIS(Moderate Resolution Imaging Spectrometer) sensor imageries.Normalized Difference Snow Index(NDSI) algorithm was used to generate multi-temporal time series snow cover maps.The results indicate large variation in snow cover distribution pattern and decreasing trend in different sub-basins of the Jhelum River.The relationship between SCE-temperature,SCE-discharge and discharge-precipitation was analyzed for different seasons and shows strong correlation.For streamflow simulation of the entire Jhelum basin Snow melt Runoff Model(SRM) used.A good correlation was observed between simulated stream flow and in-situ discharge.The monthly discharge contribution from different sub-basins to the total discharge of the Jhelum River was estimated using a modified version of runoff model based on temperature-index approach developed for small watersheds.Stream power - an indicator of the erosive capability of streams was also calculated for different sub-basins. 展开更多
关键词 Snow cover extent(SCE) Streamflow Snow Melt Runoff Model(SRM) Normalized Difference Snow Index(NDSI) Jhelum basin Moderate Resolution Imaging Spectrometer(MODIS)
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Assessing impact of climate change on forest cover type shifts in Western Himalayan Eco-region 被引量:1
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作者 p.k.joshi Asha Rawat +1 位作者 Sheena Narula Vinay Sinha 《Journal of Forestry Research》 CAS CSCD 2012年第1期75-80,共6页
Climate is a critical factor affecting forest ecosystems and their capacity to produce goods and services. Effects of climate change on forests depend on ecosystem-specific factors including dimensions of climate (te... Climate is a critical factor affecting forest ecosystems and their capacity to produce goods and services. Effects of climate change on forests depend on ecosystem-specific factors including dimensions of climate (temperature, precipitation, drought, wind etc.). Available infor- mation is not sufficient to support a quantitative assessment of the eco- logical, social and economic consequences. The present study assessed shifts in forest cover types of Western Himalayan Eco-region (700-4 500 m). 100 randomly selected samples (75 for training and 25 for testing the model), genetic algorithm of rule set parameters and climatic envelopes were used to assess the distribution of five prominent forest cover types (Temperate evergreen, Tropical semi-evergreen, Temperate conifer, Sub- tropical conifer, and Tropical moist deciduous forests). Modelling was conducted for four different scenarios, current scenario, changed precipi- tation (8% increase), changed temperature (1.07℃ increase), and both changed temperature and precipitation. On increasing precipitation a downward shift in the temperate evergreen and tropical semi-evergreen was observed, while sub-tropical conifer and tropical moist-deciduous forests showed a slight upward shift and temperate conifer showed 'no shift. On increasing temperatm'e, an upward shift in all forest types was observed except sub-tropical conifer forests without significant changes. When both temperature and precipitation were changed, the actual dis- tribution was maintained and slight upward shift was observed in all the forest types except sub-tropical conifer. It is important to understand the likely impacts of the projected climate change on the forest ecosystems, so that better management and conservation strategies can be adopted for the biodiversity and forest dependent community. Knowledge of impact mechanisms also enables identification and mitigation of some of the conditions that increase vulnerability to climate change in the forest sector. 展开更多
关键词 Climate change forest cover types SHIFT western Himalaya genetic algorithm
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Assessing forest fragmentation in north-western Himalaya:a case study from Ranikhet forest range,Uttarakhand,India 被引量:1
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作者 Mohit Sharma Anusheema Chakraborty +1 位作者 J.K.Garg p.k.joshi 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期319-327,共9页
The northwestern Himalaya harbors high levels of biodiversity due to its unique topography, climatic conditions and heterogeneity. Forest fragmentation is one of the major threats causing a decline in biodiversity in ... The northwestern Himalaya harbors high levels of biodiversity due to its unique topography, climatic conditions and heterogeneity. Forest fragmentation is one of the major threats causing a decline in biodiversity in the Himalayan region. We assesses forest fragmentation and changes in land use land cover(LULC) patterns using multi-temporal satellite data over a time span of four decades(1976–2013). Fragmentation analysis using the Landscape Fragmentation Tool(LFT) reveals a decrease in core and edge areas by 14 and 2.3 %, respectively; while an increase in non-forest, patch area and perforation area by 2.1, 0.4, and 14 %, respectively. The LULC dynamics show that the areas under dense forest and scrub forest have decreased by 2.8 % and 1.9 %, respectively; and there is an increase in open forest, crop land and fallow land area by 2.6, 1.7 and 2.1 %, respectively. The quantification of landscape heterogeneity is undertaken with the help of landscape metrics computed using FRAGSTATS at class and landscape level, showing signs of increased fragmentation. Our study provides baseline database that can support the future biodiversity conservation and sustainable forest management initiatives. 展开更多
关键词 fragmentation landscape patch biodiversity heterogeneity Himalayan climatic FRAGSTATS showing northwestern
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Resource Utilization Pattern Analysis in Pali Gad Watershed of Tehri,Garhwal Himalaya(India)
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作者 LI Qiao-Hong p.k.joshi +2 位作者 YANG Xue-Fei NLee XU Jian-Chu 《云南植物研究》 CSCD 北大核心 2009年第6期551-558,共8页
The western Himalaya has had a central role as a life support system for the local people and as a source of ecologgical services.This long term use of these resources,including livestock grazing,fuel wood collection ... The western Himalaya has had a central role as a life support system for the local people and as a source of ecologgical services.This long term use of these resources,including livestock grazing,fuel wood collection and a variety of other uses,has shaped its montane cultural landscape.The present paper focuses on resource utilization in the Pall Gad watershed,which consists of 25 villages situated in the lesser Himalaya.Using a satellite derived map,natural resources available in this area were assessed,and the ecosystem services provided by them and level of pressure on them were com-puted through a door to door socioeconomic survey.The study revealed a spatio-temporal variation in the resource demand and extraction at the permanent villages.Average fuel wood consumption was 1.12 kg/day/capita,fodder consumption was 3.69 kg/day/capita from lopping and 3.25 kg/day/capita from grass collection from forest.An attempt has been taken toevaluate the ecosystem services.The forest provides more provisional and regulatory services,whereas agriculture provides more supporting services and river bed/water bodies serve more cultural purposes for the locals.This study contributes an example of a human shaped ecosystem in a mountainous region where an additional fragmentation of natural resources exists.An increase in resource demand has been noticed in the less productive lands of the region.This has resulted in increased resource extraction from the entire watershed may not be sustainable in the long run. 展开更多
关键词 Ecosystem services Himalaya Pali Gad Resource utilization and demand
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