基于MODIS遥感数据的贵州省森林物候监测

Using MODIS Satellite Remote Rensing to Monitor Phenological Seasonal Changes of Forest in Guizhou Province

以贵州省森林植被为研究对象,基于对MODIS卫星遥感影像的分析,探讨了遥感监测手段在区域尺度上提高森林植被物候监测精细程度的可能性。结果表明:通过分析比较归一化植被指数(NDVI)、增强植被指数(EVI)、相对绿度指数(Gcc)、绝对绿度指数(ExG)等不同植被指数,发现增强型植被指数(EVI)更能表达森林植被物候变化趋势;采用S-G滤波及动态阈值法提取物候关键期,发现贵州省森林植被物候变化趋势呈现西部地区植被生长开始期晚于东部地区,结束期早于东部地区,整个植被生长季长度西部短于东部;基于EVI的贵州省森林物候空间分异规律总体上不明显,仅纬度与生长开始期(SOS)和生长季长度(LOS)相关性显著,经度海陆地带性及海拔垂直地带性差异不显著。

Based on MODIS satellite remote sensing images,this paper discusses the possibility of remote sensing monitoring methods to im⁃prove the fineness of forest vegetation phenology monitoring at regional scale.The results are as follows:By comparing the differences in different vegetation indices such as NDVI,EVI,Gcc and ExG,it was found that the enhanced vegetation index(EVI)better expressed the trend of plant phenology changes;by using S-G filtering and dynamic threshold method to extract the key phenological periods,it is found that the phenologi⁃cal change trend of forest vegetation in Guizhou Province shows that the starting period of vegetation growth in the western region is later than that in the eastern region,the ending period is earlier than that in the eastern region,and the length of the whole vegetation growth season in the western region is shorter than that in the eastern region;the law of forest phenological spatial differentiation in Guizhou Province based on EVI was not obvious,only the latitude has a significant correlation with the start of growth(SOS)and the length of growth season(LOS),and the longitude sea land zonality and the elevation vertical zonality have no significant differences.