Simulation of dynamic changes and diffusion of typical vegetation populations in coastal wetlands in the Yellow River Delta

Satellite remote sensing, GIS spatial analysis and biological population diffusion were combined to understand temporal and spatial dynamic changes and development trends of typical wetland vegetation in the Yellow River Delta．Remote sensing images of coastal wetlands in the Yellow River Delta in 1996, 2006, and 2016 were used for object-oriented classification, landscape type transfer matrix, and Land Use Gravity Transfer to outline dynamic changes．CA-Markov model in IDRISI 17.0 was used to forecast changes in coastal wetland in 2026. Forecasting and analysis of future changes in Spartina alterniflora and Suaeda salsa were shown．Spartina alterniflora was found to increase from 3.45 km² in 1996 to 25.14 km² in 2016, whereas Suaeda salsa decreased significantly．Oilfield development on the Yellow River was found to have produced a Spartina alterniflora connectivity block, center of Spartina alterniflora gravity had moved from edge of Shengli Oilfield to estuary．The center of Suaeda salsa gravity had receded slightly inland. Forecast for 2026 indicated that Spartina alterniflora would reach 26.67 km² and Suaeda salsa 26.15 km²．From 2006 to 2016, Spartina alterniflora and Suaeda salsa had changed dramatically. Human activities in coastal wetlands have increased over 20 years. Strong influences by natural disasters (diversions, cutoffs, storm surges and others) in the Yellow River Delta estuary in the 20 year period had seriously impacted the growth environment of Spartina alterniflora and Suaeda salsa, resulting in low accuracy of individual prediction．If this growth trend is not put under control, swelling of Spartina alterniflora in 2026 will likely negatively impact the ecological environment in the Yellow River Delta．