The Establishment of GIS based Simulation Model of Saltwater Intrusion in Pearl River Estuary, South China: A Case Research in the Mo-dao-men Watercourse, Pearl River Estuary

the need and imminence of saltwater monitoring and predicting in river net area of Pearl River Delta are clarified based on the occurring and review of saltwater disaster historically. However, most works still depend on field measurement, which spends a great deal of manual and material resources with low efficiency nowadays. Chlorosity, wind speed and river discharge of each observation station have been collected in recent years (2004 ~ 2006) at Mo-dao-men watercourse of Pearl River estuary, South China, when saltwater intrusion occurred. The intensity, scope and time of saltwater intrusion are analyzed by spatial analysis of GIS combing local vector map based spatial data, and the relation among salinity, runoff, tidal current, the geometry of estuary and wind speed is analyzed, their function relation is induced. Finally, the simulation model of saltwater intrusion is established at Mo-daomen watercourse of Pearl River estuary, South China, in addition the simulation graph of saltwater intrusion of 14 January 2006 of Mo-dao-men watercourse is forecasted based on the model, and it is very close to field data. At the same time dynamic process which saltwater intrusion occurred, developed and weakened can be simulated with advanced GIS based on the predictive model of salinity during the dry seasons, which can provide decision supporting for quick reaction after hyperspectral remote sensing monitoring of saltwater intrusion. So, corresponding measures can be earliest adopted and disaster of saltwater intrusion be reduced to minimization. Keywords-Mo-dao-men watercourse; saltwater intrusion; GIS; simulation model