The responses of evapotranspiration due to changes of LUCC under seawater intrusion in a coastal region

Abstract

The paper provides a coherent pattern identification analysis of the impacts of coastal land use and land cover (LULC) on evapotranspiration (ET) under the impact of seawater intrusion. The study applied the Landsat satellite data to characterize the LULC at Laizhou Bay, Shandong Province, China. Then, the ET and heat fluxes were estimated using the surface energy balance algorithm for land model with two-time phase thermal infrared band images and regional surface parameters. This allowed for the eventual linkage of seawater intrusion to land use/cover changes (LUCC) and ET variations over time. The case study discussed in this paper carried out a coastal landscape dynamics assessment using multi-source and multi-sensor remote sensing technologies. The results are: (1) due to its distance from the sea, the vegetation index (modified soil-adjusted vegetation index, MSAVI) gradually increases with the gradual increase of land use grade (Uindex); (2) there are a variety of types of relational patterns between parameters (LST, G(n), MSAVI, and Uindex) and ET (positive, negative, and no relationship); and (3) seawater intrusion significantly affected the spatial pattern of LUCC, which evidently affected the spatial distribution of ET. The spatial distribution pattern and change characteristics of ET were formed by double driving forces of seawater intrusion and LUCC under the background effects of regional climate.