Analysis of the Expanding Process of the Spartina Alterniflora Salt Marsh in Shanyutan Wetland, Minjiang River Estuary by Remote Sensing

Abstract Spatio-temporal dynamics of Spartina alterniflora marshes in the Shanyutan Wetland, Minjiang River estuary in 2006 and 2010 were studied by the aerial images and Google Earth stellite images and field investigations. The expansion of S. alterniflora was significant, the areas were 211.03 hm2 and 306.94 hm2, respectively in 2006 and 2010. They mainly distributed in the middle tidal flat and extended quickly from northwest to southeast. Number of Patches of S. alterniflora marsh decreased by 59.17%, Mean Patch Size increased by 266.67%, Patch Shape Index decreased from 23.28 to 19.50. 85.03 hm2 of mudflats changed to S. alterniflora marshes, accounting for 72.54% of the area of increased S. alterniflora marsh, and mainly occurred in low tidal flat and surrounding areas of tidal creeks in east and central zones.