Influence of drought duration and severity on drought recovery period for different land cover types: evaluation using MODIS-based indices

Drought is a slow-onset phenomenon driven by the lack of precipitation, affecting the performance of plants and functionality of terrestrial ecosystems. In addition to the length and severity of drought, the period it takes for the plants to return to normal conditions is critical. Remote sensing data with appropriate spatial and temporal coverage facilitates monitoring drought and its consequences on local and global scales. This study investigated the influence of drought duration and severity on the drought recovery period (DRP) for different land use and land cover (LULC) types in Iran. The moderate resolution imaging spectroradiometer (MODIS)-based vegetation health index (VHI) was used to monitor drought in the period 2000-2020. The results identified 2000, 2001, and 2008 as drought years. DRP was estimated using gross primary productivity (GPP). The findings revealed that shrubland and cropland experienced more prolonged droughts than forests, which experienced the shortest drought duration. Similarly, shrublands and croplands had the most prolonged recovery, and forests had the shortest recovery time. A direct relationship was observed between drought severity and DRP in all LULC types, however the local correlation between drought duration and recovery time better revealed the heterogeneity of relationships. This study provides valuable information on the drought resilience of different LULC types for use in achieving better management and a deeper understanding of drought.

Automated summary

Drought duration and severity affect the recovery period of different land use and land cover types in Iran, with shrublands and croplands experiencing longer droughts and recovery times compared to forests. There is a direct relationship between drought severity and recovery period, however, the correlation between drought duration and recovery time varies geographically.