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2000–2017年中巴经济走廊逐年荒漠化分布数据集 被引量:5
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作者 敏玉芳 冯克庭 +1 位作者 康建芳 艾鸣浩 《中国科学数据(中英文网络版)》 CSCD 2019年第3期71-81,共11页
土地荒漠化是目前世界上最为严重的生态环境问题之一。监测土地荒漠化动态变化,掌握其变化规律对防治荒漠化有很重要的意义。中巴经济走廊是“一带一路”的重要组成部分,全长约3000公里,其中1300余公里为严寒高原、干旱和荒漠区段。尤... 土地荒漠化是目前世界上最为严重的生态环境问题之一。监测土地荒漠化动态变化,掌握其变化规律对防治荒漠化有很重要的意义。中巴经济走廊是“一带一路”的重要组成部分,全长约3000公里,其中1300余公里为严寒高原、干旱和荒漠区段。尤其是在南段,干旱和大面积荒漠是其主要的生态环境约束因素。本文采用荒漠化差值指数(DDI)评价中巴经济走廊荒漠化程度,以归一化植被指数(NDVI)与地表反照率(Albedo)为监测指标,通过构造Albedo-NDVI特征空间,并利用Albedo和NDVI之间负相关的关系,构建DDI公式,完成2000–2017年中巴经济走廊荒漠化分类专题数据集。并通过高分辨率Landsat数据反演的植被覆盖度验证本数据集的质量和精度。以2010年数据为例,总体评价精度达到81.67%,Kappa系数为75.42%。本数据集直观反映中巴经济走廊荒漠化程度,为定量评价此区域的荒漠化严重程度提供参考,并为中巴经济走廊沿线国家进行荒漠化防治工作以及宏观决策的制定提供基础资料。 展开更多
关键词 中巴经济走廊 荒漠化分布 Albedo-NDVI特征空间 DDI荒漠化差异指数 Albedo地表反照率
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Spatial Distribution and Dynamic Changes in Research Hotspots for Desertification in China based on Big Data from CNKI 被引量:2
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作者 LIANG Yuting HU Yunfeng HAN Yueqi 《Journal of Resources and Ecology》 CSCD 2019年第6期692-703,共12页
Desertification research plays a key role in the survival and development of all mankind.The Normalized Comprehensive Hotspots Index(NCH)is a comprehensive index that reveals the spatial distribution of research hotsp... Desertification research plays a key role in the survival and development of all mankind.The Normalized Comprehensive Hotspots Index(NCH)is a comprehensive index that reveals the spatial distribution of research hotspots in a given research field based on the number of relevant scientific papers.This study uses Web Crawler technology to retrieve the full text of all Chinese journal articles spanning the 1980s-2018 in the Chinese Academic Journal full-text database(CAJ)from CNKI.Based on the 253,055 articles on desertification that were retrieved,we have constructed a research hotspot extraction model for desertification in China by means of the NCH Index.This model can reveal the spatial distribution and dynamic changes of research hotspots for desertification in China.This analysis shows the following:1)The spatial distribution of research hotspots on desertification in China can be effectively described by the NCH Index,although its application in other fields still needs to be verified and optimized.2)According to the NCH Index,the research hotspots for desertification are mainly distributed in the Agro-Pastoral Ecotone and grassland in Inner Mongolia,the desertification areas of Qaidam Basin in the Western Alpine Zone and the Oasis-Desert Ecotone in Xinjiang(including the extension of the central Tarim Basin to the foothills of the Kunlun Mountains,the sporadic areas around the Tianshan Mountains and the former hilly belt of the southern foothills of the Altai Mountains).Among these three,the Agro-Pastoral Ecotone in the middle and eastern part of Inner Mongolia includes the most prominent hotspots in the study of desertification.3)Since the 1980s,the research hotspots for desertification in China have shown a general downward trend,with a significant decline in 219 counties(10.37%of the study area).This trend is dominated by the projects carried out since 2002.The governance of desertification in the eastern part of the Inner Mongolia-Greater Khingan Range still needs to be strengthened.The distribution of desertification climate types reflects the distribution of desertification in a given region to some extent.The Normalized Comprehensive Hotspots Index provides a new approach for researchers in different fields to analyze research progress. 展开更多
关键词 big data web crawler research hotspots DESERTIFICATION spatial distribution trend analysis China
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