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伊朗西北部 Varzeghan 附近晚中新世一些新化石地点的大哺乳动物(英文)
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作者 Majid MIRZAIE ATAABADI Gholamreza ZAREE Zahra ORAK 《古脊椎动物学报》 CSCD 北大核心 2011年第3期311-321,共11页
首次报道了伊朗西北部 Varzeghan 附近发现的大型哺乳动物化石,材料包括三趾马和恐象。根据个体大小和形态特征,将三趾马标本暂时分为一个小至中型类似 Hipparion moldavicum 的种和一个中至大型类似 H. prostylum 或 H. dietrichi 的种... 首次报道了伊朗西北部 Varzeghan 附近发现的大型哺乳动物化石,材料包括三趾马和恐象。根据个体大小和形态特征,将三趾马标本暂时分为一个小至中型类似 Hipparion moldavicum 的种和一个中至大型类似 H. prostylum 或 H. dietrichi 的种。Deinotherium giganteum 也出现于这一地区。依据与其他晚中新世地点哺乳动物化石的对比,这些新化石地点的时代推测为吐洛里期( Turolian) 中期或相当于欧洲哺乳动物带的 MN12。 展开更多
关键词 伊朗 马拉盖 Varzeghan 中新世Turolian期 哺乳动物
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Multi-temporal forest cover dynamics in Kashmir Himalayan region for assessing deforestation and forest degradation in the context of REDD+ policy 被引量:2
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作者 Akhlaq Amin WANI Pawan Kumar JOSHI +1 位作者 Ombir SINGH Sumera SHAFI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1431-1441,共11页
The role of forests is being actively considered under the agenda of REDD+ (Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and fore... The role of forests is being actively considered under the agenda of REDD+ (Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and forest quality. Forests in general have undergone negative changes in the past in the form of deforestation and degradation, while in some countries positive changes are reported in the form of conservation, sustainable management of forests and enhancement of carbon stock. The present study in the Kashmir Himalayan forests is an effort to assess historical forest cover changes that took place from 1980 to 2009 and to predict the same for 2030 on the basis of past trend using geospatial modeling approach. Landsat data (Multispectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+)) was used for the years 1980, 199o and (2001, 2009) respectively and change detection analysis between the dates was performed. The maps generated were validated through ground truthing. The study area (3375.62 km^2) from 1980-2009 has uffered deforestation and forest degradation of about 126 km^2 and 239.02 km^2 respectively which can be claimed under negative options of REDD+, while as the area that experienced no change (1514 km^2) can be claimed under conservation. A small area (23.31 km^2) observed as positive change can be claimed under positive options. The projected estimates of forest cover for 2030 showed increased deforestation and forest degradation on the basis of trend analysis using Cellular Automata (CA) Markov modeling. Despite the fact that country as a whole has registered a net positive change in the past few decades, but there are regions like Kashmir region of western Himalaya which have constantly undergoing deforestation as well as degradation in the past few decades. 展开更多
关键词 DEFORESTATION Degradation Coniferous forests Carbon emission HIMALAYA
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Detecting Forest Fire Prone Areas Using Object-Based Image Analysis and GIS Techniques: A Case Study in Kayer Khola, Nepal
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作者 Kabir Uddin Petra Fǖreder 《Journal of Environmental Science and Engineering(B)》 2012年第6期748-755,共8页
Every year during summer, natural and human-induced forest fires threaten the environment in the largely forested areas of the Himalayan region and the local population living near these forests. Nepal, with its multi... Every year during summer, natural and human-induced forest fires threaten the environment in the largely forested areas of the Himalayan region and the local population living near these forests. Nepal, with its multitude of forests, is one of the most forest fire-prone areas in the region. This study examines the possibility of averting forest fires, minimizing their frequency and the damage they cause, through advanced mapping of forest fire prone areas using a VHSR (very-high spatial resolution) satellite image of GeoEye-1, DEM (digital elevation data) created from topographic maps and additional data layers (e.g., precipitation, settlements). The study was conducted in Kayer Khola, Chitwan district, Nepal. The classification of the satellite image has been performed using OBIA (object-based image analysis) techniques taking into account spectral, spatial and context information as well as hierarchical properties. The land cover classification result was thereafter combined with additional data in ArcGIS, where the input layers were reclassified and all classes of the input layers ranked according to their proneness to forest fires. Fire prone areas were delineated in five classes ranging from very high to very low. The study revealed that 82% of fires occur in forest areas. This case study in Kayer Khola shows that OBIA and GIS modeling techniques can be used to successfully identify forest fire-prone areas. The mapping of forest fire-prone areas will enable forest departments in countries of the Himalayan region to delineate forest fire prone areas, which can guide the forest departments set up appropriate fire-fighting infrastructure in these areas and thus help, minimize or avert forest fires. 展开更多
关键词 Remote sensing GIS (geographic information system) SEGMENTATION forest fire.
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