HJ-1A NDVI与MODIS NDVI时间序列提取植被物候特征对比研究

Comparative Studyon Extracting Vegetation Phenology Information from HJ-1A NDVI and MODIS NDVI Time Series

以HJ-1A和MODIS为数据源,通过动态阈值法提取物候特征参数,对HJ-1A NDVI和MODIS NDVI时间序列进行植被物候特征提取进行定性和定量比较,通过比较结果,提出HJ-1A NDVI数据在该应用中存在的问题,促进国产中空间高时间分辨率影像数据在植被物候信息提取研究中的应用,提高其在生态系统研究中的应用价值。结果表明:在SOS、EOS和LOS以及TOMS几个主要的物候时间点上,MODIS NDVI时间序列的标准差较小,所得物候数据更为集中,偏离度较小,所得物候数据较稳定;而HJ-1A NDVI时间序列所得物候数据的标准差较大,数据偏离程度较大,而在POS、BOS和AOS等表征植被生命周期中生长幅度数据上,其标准差较小,离散程度小。

Taking HJ-1A and MODIS as data source, the comparison study of HJ-1A NDVI and MODIS NDVI time series for extracting the vegetation phenology based on the method of dynamic threshold is ana- lyzed qualitatively and quantitatively.Through compared results, some issues of application of HJ-1A NDVI on vegetation can be analyzed which will improve the application of relatively high spatio-temporal remote sensing data on the urban vegetation.The results showed that the standard deviation of MODIS NDVI time series is small on the main phenological points of SOS, EOS, LOS and TOMS. There is a big difference from the standard deviation of HJ NDVI time series which is relatively big, however, on the main phenolog- ical points of POS,BOS and AOS,the standard deviation and the degree of discrete of HJ NDVI time series is small.For the different types of vegetation, HJ-1A NDVI time series can be used to extract the vegetation phenology.