基于多源遥感融合下的准格尔旗植被变化研究

Study on Vegetation Changes in Jungar Banner Based on Multi-Source Remote Sensing Fusion

摘要: 本研究基于谷歌地球引擎(Google Earth Engine, GEE)云平台，使用GF-SG多源遥感融合方法得到高时空分辨率的两波段增强植被指数(EVI)，采用趋势检验、突变点分析、偏相关分析等方法，对2002~2022年准格尔旗的植被时空变化进行分析，探讨了植被覆盖的变化趋势及其影响因素。结果表明：(1) 2002~2022年，准格尔旗的平均EVI显著上升，EVI值于2016年产生突变，风沙区和平原区EVI值增幅显著；(2) 植被稳定性分析显示，大部分区域波动较小，生态环境持续改善；(3) 森林的EVI增长速度最快，草地EVI的增长最慢；(4) 不同坡向与海拔EVI值有明显差异，偏东坡EVI值高，偏西坡EVI值低，EVI值随海拔的上升而降低；(5) 气温、降水、蒸散对EVI正向影响明显，降水在季前1个月影响最为显著，气温则在季前3~5个月的中长期累积效应更为显著。研究结果为干旱半干旱地区植被变化及其驱动机制提供了重要参考。

Abstract: This study is based on the Google Earth Engine (GEE) cloud platform and uses the GF-SG multi-source remote sensing fusion method to obtain a two-band enhanced vegetation index (EVI) with high temporal and spatial resolution. Using methods such as trend analysis, change-point detection, and partial correlation analysis, this study examines the spatiotemporal changes in vegetation in Jungar Banner from 2002 to 2022, exploring the trends in vegetation coverage and their influencing factors. The results show that: (1) the average EVI of Jungar Banner increased significantly from 2002 to 2022, and the EVI value changed suddenly in 2016. The EVI values in the sandy and plain areas increased significantly; (2) the vegetation stability analysis showed that most areas have small fluctuations, and the ecological environment continues to improve; (3) The EVI of forests has the fastest growth rate, and the EVI of grasslands has the slowest growth rate; (4) There are obvious differences in EVI values at different slopes and altitudes, with higher EVI values on the eastern slopes , the EVI value is low on the west slope, and the EVI value decreases with increasing altitude; (5) Temperature, precipitation, and evapotranspiration have a significant positive impact on EVI, with precipitation having the most significant impact in the first month of the season, and temperature having the most significant impact in the first three months of the season. The medium- to long-term cumulative effect of 3~5 months is more significant. The research results provide an important reference for vegetation changes and their driving mechanisms in arid and semi-arid areas.