A comparison of red, NIR, and NDVI for monitoring temporal burn signature change in tallgrass prairie

Prescribed burning in tallgrass prairie benefits both human and natural systems. However, negative aspects of burning, such as air pollution, also exist. Balancing the advantages and disadvantages of burning requires knowledge of the burn regime in the tallgrass system. One way to acquire this knowledge is by mapping burned areas with remotely sensed data. Unfortunately, burned area mapping is often complicated by the transient nature of burn scars, by cloud cover, and by a lack of spectral contrast between burned areas and non-burned senescent vegetation. In this study, we used in situ measurements of spectral reflectance to track the efficacy of bandpasses that simulated Moderate Resolution Imaging Spectroradiometer (MODIS) and Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM+) sensor responses. Our results showed that red and Normalized Difference Vegetation Index (NDVI) outperformed Near-Infrared (NIR) for delineating burned areas. From these findings it is clear that identifying/mapping burned areas can be performed accurately for several months with either red reflectance or NDVI.