A suitable NDVI product for monitoring spatiotemporal variations of LAI in semiarid mixed grassland

作者：Li Zhaoqin; Guo Xulin^*

来源：Canadian Journal of Remote Sensing, 2012, 38(6): 683-694.

Routinely produced Normalized Difference Vegetation Index (NDVI) products are an important source for leaf area index (LAI) in terrestrial modelling. However, little research has focused on the performance of NDVI products to identify intra-annual spatial variations of LAI in semiarid mixed grasslands where a large amount of dead plant material exists. The objective of this study was to determine a suitable NDVI product to identify spatial variation of LAI between tame and native grassland during the entire growing season in the St. Denis wildlife reserve area, Saskatchewan. MODIS 250 m NDVI products were evaluated for monitoring spatiotemporal variations of LAI by comparisons with NDVI data at 0.5 m, 10 m, and 20 m spatial resolution. Results indicate that MODIS 250 m NDVI data are closely correlated with the ground measured NDVI data with a correlation coefficient of 0.90. NDVI products with a spatial resolution of 250 m or higher can differentiate LAI of land cover types during the entire growing season in the study area. MODIS 250 m NDVI product is qualified to be a model input describing spatiotemporal variations in LAI in semiarid mixed grasslands characterized by a large amount of dead plant materials.

• 出版日期2012-12