【摘 要】
：
Using observed snow cover data from Chinese meteorological stations, this study indicated that annual mean snow depth, Snow Water Equivalent (SWE), and snow density during 1957-2009 were 0.49 cm, 0.7
【出 处】
：
Sciences in Cold and Arid Regions
论文部分内容阅读
Using observed snow cover data from Chinese meteorological stations, this study indicated that annual mean snow depth, Snow Water Equivalent (SWE), and snow density during 1957-2009 were 0.49 cm, 0.7 mm, and 0.14 g/cm 3 over China as a whole, respectiv
其他文献
粮食主产区在我国农业生产中具有举足轻重的地位,也是我国农业碳排放的主要来源。科学地把握当前我国粮食主产区农业碳排强度、区域差异及成因是合理构建农业碳减排政策体系、实现农业碳减排的重要前提。本文首先基于8方面指标,运用主成分分析法对我国13个粮食主产省(区)农业碳排强度进行测度,结果表明,湖南、山东、湖北农业碳排强度居前三位;吉林、黑龙江、内蒙古则位于后三位。在此基础上,构建农业碳排效应区域差异评价
The Zoige Wetland is located in the northeastern Qinghai-Tibetan Plateau, which is highly sensitive to global environment change and human disturbance because of its high elevation and cold environmen
The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 20
通过IAU最新公布的撞击坑名录、"嫦娥一号"影像与DEM数据,本文使用数理统计和空间分析的方法研究了月球正面撞击坑分布的空间不均衡性。主要体现在:(1)月球正面直径较大的撞击坑主要分布在月陆区域,且集中趋势明显,而月海区域直径较大的撞击坑分布较少,周围有大量直径较小的撞击坑;(2)直径较大的撞击坑在月表具有一定随机性,而直径较小的撞击坑在月表的集中性明显;(3)赤道区域的撞击坑密度小于两极区域,前
与站点统计降尺度插值和动力降尺度相比,高精度曲面建模(HASM)降尺度,具有不需大尺度预报因子,直接从GCM结果构建区域上高空间分辨率的未来气候模拟曲面的优势。HASM降尺度将未来气候,分为历史观测拟合的气候基准值和GCM未来气候变化值进行模拟,精度明显高于传统方法,但常系数全局拟合的气候基准值忽略了降水分布的空间非平稳性,导致降水模拟受到较大影响。为增强降水降尺度的气候背景值的描述能力,通过分析
反照率是一个广泛应用于地表能量平衡、中长期天气预测和全球变化研究的重要参数。本文利用2010年的TM影像反演北京地区地表反照率,首先利用6S模型对影像进行大气校正,得到地表反射率,进而,利用TM的5个波段的反射率,根据经验公式,计算了北京地区的地表反照率;对北京市地表反照率的分布情况、不同下垫面的反照率、以及反照率与LST和NDVI的关系进行了分析,得出了结论。
Correlations of soil properties and fruit size of Calligonum mongolicum Turcz.and related species were analyzed.The results showed that the particle size characteristics of soils for growing Calligonu
Pollen limitation of plant reproduction occurs across Angiosperms,particularly those in patched habitats.We investigated the relationship between pollen limitation and patch variables (patch size,visi
Two psammophile-dominated Artemisia semi-shrubs (A.wudanica and A.halodendron) and two annual Artemisia forbs (A.sieversiana and A.scoparia) bear significant ecological functions in Horqin Sandy Land,
This paper studies the key techniques of the measurement and communication system for inter-satellite links(ISLs) of global navigation satellite system.A fixed link topology is designed based on the a