Abstract Mountain ecosystems of the Himalaya have warmed more rapidly in recent decades than other areas of the globe. Landscape-level delineation of treeline position and its dynamics can give insight regarding climatic variability. Landsat-2 Multispectral Scanner (MSS), Resourcesat-2 Linear Imaging Self Scanning Sensor (LISS-III) and National Oceanic and Atmospheric Administration- Advanced Very High Resolution Radiometer (NOAA-AVHRR) derived normalized difference vegetation index (NDVI) was used to study the long-term treeline dynamics. The treeline has shifted vertically 301 ± 66 m upward in 37 years at a rate of c. 81 m decade−1. The minimum air temperature has increased at a rate of 0.3 °C decade−1 (p < 0.001) depicting the favourable scenario for treeline growth in this temperature limited ecosystem. The annual cumulative precipitation has decreased at a rate of 206.5 mm decade−1. The length of growing season (LOS) has increased and the start (SOS) and end of growing season (EOS) has got earlier in the 1977 treeline. The elevation shifts and phenological changes of the treeline were observed in the warming scenario.

中文翻译：

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评估锡金喜马拉雅山林线位置和地表物候变化

摘要 近几十年来，喜马拉雅山的山地生态系统比全球其他地区变暖得更快。林木线位置及其动态的景观级划定可以提供有关气候变化的洞察力。Landsat-2 多光谱扫描仪 (MSS)、Resourcesat-2 线性成像自扫描传感器 (LISS-III) 和国家海洋和大气管理局 - 高级甚高分辨率辐射计 (NOAA-AVHRR) 衍生的归一化差异植被指数 (NDVI) 用于研究长期的树线动态。树线在 37 年中以 c 的速度垂直向上移动 301 ± 66 m。81 m 十年−1。最低气温以 0.3 °C 的速度增加了十年-1 (p < 0.001)，描绘了在这个温度有限的生态系统中树线生长的有利情况。年累积降水量以 206.5 毫米十年−1 的速度减少。在 1977 年的林线中，生长季节 (LOS) 的长度增加了，并且生长季节的开始 (SOS) 和结束时间 (EOS) 提前了。在变暖情景中观察到树线的海拔变化和物候变化。