Landsat时序数据支持下的藏东南植被时空变化监测

本文利用GEE平台和1990—2019年巴宜区Landsat遥感影像，采用像元二分模型、相关性分析等方法分析了巴宜区植被覆盖度的时空变化特征与驱动力。研究结果表明：①1990—2019年巴宜区植被覆盖度总体呈稳中有增的趋势，其中，河谷区域增加明显，而高海拔区域相对稳定；②1990—2019年巴宜区气温呈显著升高，降水略有下降，总体呈“暖干化”，气温较降水量对植被覆盖变化更明显，但气候变化对植被覆盖变化影响总体不明显；③1990—2019年巴宜区植被覆盖变化与人类活动有很好的相关性，其中，低、中低、中、中高植被覆盖区域，呈显著的负相关，而高植被覆盖区域呈正相关。本文基于遥感大数据和地理云计算的植被覆盖监测动态监测和定量分析方法，能对高山峡谷区生态评估和演替分析提供一定的技术支撑和科学数据。

Monitoring on spatial-temporal vegetation dynamics based on Landsat time series

The purpose of this paper is to analyze the spatial-temporal pattern of vegetation coverage and driving factors in Bayi district, using pixel dichotomy model and correlation analysis methods, from Landsat time series images between 1990 and 2019 based on GEE platform. Research results show: ①The overall trend on vegetation coverage emerged as an approximate stability with a little increasing, among which the valley regions increased significantly while the high mountain regions is relatively stable. ②Temperature in Bayi district increased significantly whereas the precipitation decreased slightly, demonstrating a “warm and dry” feature. The response of vegetation coverage to precipitation is stronger than temperature, but however the relationship between climate change and vegetation coverage is not significant generally. ③A good relationship is found between human activities and vegetation cover, where the non-high vegetation coverage areas presented in significant negative correlation while the high vegetation coverage areas had positive correlation. The proposed methods of dynamic monitoring on vegetation coverage and quantitative analysis using remote sensing big data and geographic cloud computing, can provide technical support and scientific data for ecological assessment and evolution analysis over alpine canyon region.