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Forest fragmentation and human population varies logarithmically along elevation gradient in Hindu Kush Himalaya-utility of geospatial tools and free data set

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Journal of Mountain Science 2017年第12期14卷 2432-2447页

作者： DAS Pulakesh BEHERA Mukunda Dev MURTHY Manchiraju Sri Ramachandra Centre for Ocean River Atmosphere and Land Sciences Indian Institute of Technology Kharagpur International Centre for Integrated Mountain Development (ICIMOD)

Hindu Kush Himalaya(HKH) is the largest and the most diverse mountain region in the world that provides ecosystem services to one fifth of the total world population. The forests are fragmented to different degrees due to expansion and intensification of human land use. However, the quantitative relationship between fragmentation and demography has not been established before for HKH vis-à-vis along elevation gradient. We used the globally available tree canopy cover data derived from Landsat-TM satellite to find out the decadal forest cover change over 2000 to 2010 and their corresponding fragmentation levels. Using SRTMderived DEM, we observed high forest cover loss up to2400 m that highly corroborated with the population distribution pattern as derived from satellite observation. In general, forest cover loss was found to be higher in south-eastern part of HKH. Forest fragmentation obtained using ‘area-weighted mean radius of gyration' as indicator, was found to be very high up to 2400 m that also corroborated with high human population for the year 2000 and 2010. We observed logarithmic decrease in fragmentation change(area-weighted mean radius of gyration value),forest cover loss and population growth during 2000-2010 along the elevation gradient with very high R^2 values(i.e., 0.889, 0.895, 0.944 respectively). Our finding on the pattern of forest fragmentation and human population across the elevation gradient in HKH region will have policy level implication for different nations and would help in characterizing hotspots of change. Availability of free satellite derived data products on forest cover and DEM, griddata on demography, and utility of geospatial tools helped in quick evaluation of the forest fragmentation vis-a-vis human impact pattern along the elevation gradient in HKH.

关键词： Tree canopy cover Topography diachronic analysis Biogeography Human impact

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Land-Use and Land-Cover Change in the Sahel Area of Keita Valley, Republic of Niger

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Journal of Environmental Protection 2016年第4期7卷 554-565页

作者： Boureima K. Yacouba Zhanqi Wang Yamba Boubacar Department of Land Resources Management School of Public Administration China University of Geosciences Wuhan China Geography Department Faculty of Arts and Human Sciences Abdou Moumouni University of Niamey Niamey Niger

Keita region is largely dependent on agriculture and livestock as the main economic activities with about 90% of the population are actively engaged in rural activities. However, these activities are dwindling at a rate that corresponds with increase in the ecosystem’s vulnerability. The following study focused on land use/land cover change in Keita. The study aims to better understand changes through diachronic analysis by integrating remote sensing and GIS. There was an interpretation of satellites imagery (1975, 1984, 1995 and 2001), and statistical techniques were used to provide quantitative analysis of land use/cover change information and drivers underlying in the study area. The changes are affected by simultaneous influence of successive droughts (1973-1974 and 1983-1984) that have transformed ecological balance, anthropogenic and livestock impacts, ecosystems degradation and policies. The land use temporal dynamics are undergone continual degradation of vegetation, the state of land saturation results in conflicts between farmer and herders, the drop in grazing areas, bare land expansion, the erosion of stream bed, and the decline in flooded plain.

关键词： Keita Valley Ecosystem’s Vulnerability diachronic analysis Ecological Balance Droughts

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Spatiotemporal Dynamics of Forest and Mountain Formations in Auras Area, Algeria

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Journal of Life Sciences 2012年第6期6卷 663-669页

作者： Yassine Beghami Mahdi Kalla Michel Thinon Hassen Benmessaoud Department of Agronomy Faculty of Sciences Exact and Life Sciences University of Mohamed Khider Bikra Algeria Institute of Veterinary Science and Agricultural Sciences Hadj Lakhdar University Batna Algeria LRNAT Laboratory Hadj Lakhdar University Batna 05000 Algeria Paul Cdzanne University IMEP UMR 6116 Avenue Escadrille Normandie-Niemen 13398 Marseille Cedex 20 France

Contrary to the countries of northern coast, the forest formations on Southern and East coast of the Mediterranean are in regression. With the combined action of the ax, fire and pasture, these ecosystems are subjected to a pressure of permanent degradation. Indeed, the degradation of the forest ecosystems represents one of the most important causes of reduction and erosion of the biodiversity in the world. The massif of Aur6s is located in the North-East of Algeria. The analysis of the spatiotemporal dynamics of this vulnerable vegetation is not approached yet. This study proposes a focus on the analysis of the dynamics of this vegetation and to study the factors of its degradation. For that, a methodological approach of diachronic follow-up between two dates was adopted by using any kind of old information sources （archives, aerial photographs, topographic maps） and recent （Images satellite of American Landsat and data of land）. The results reveal a degradation of vegetable cover thus expressing a very thorough reduction of the formations forest replaced by herbaceous formations very sensitive and threatened by the overgrazing.

关键词： Aures diachronic analysis cedar forest formations remote sensing

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我国媒介融合研究20年之进路

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新闻与传播 2018年第12期

作者：韩立新张秀丽

1996-2017年20余年间，学者对媒介融合的研究为“现象”所牵引，表现为一个从概念、定义到现象和规制的演进路径，媒介融合的主体研究、载体研究、从业人员及用户研究、产业及政策研究是研究成果聚集的四个方面，呈现出与媒介融合技术... 详细信息

1996-2017年20余年间，学者对媒介融合的研究为“现象”所牵引，表现为一个从概念、定义到现象和规制的演进路径，媒介融合的主体研究、载体研究、从业人员及用户研究、产业及政策研究是研究成果聚集的四个方面，呈现出与媒介融合技术先导性特征不相一致的现象化特征，可以说是一场历时旷久的缺乏知识融合的媒介融合研究。我国媒介融合研究对媒介融合技术先导性的实质关注不足，新闻传播学科领域的媒介融合研究在整体上并没有形成知识融合的研究取向，知识创新陷入困境，媒介融合急需展开跨学科研究。技术先导性的缺位是导致我国新闻传播学科学术研究滞后于媒体实践的主要原因。

关键词：媒介融合文献计量学知识图谱共时分析历时分析 media convergence Bibliometrics knowledge mapping synchronic analysis diachronic analysis

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