关键词: 海滨湿地, 生态过程, 盐城自然保护区, 景观模型

Abstract:

Wetlands are one of the most important ecological systems on earth. Their unique ecosystem function has been sometimes called"the earth's filtration system". Coastal wetland is an important type of wetland, which is not only a rare ecosystem but is also often found in areas disturbed by human activities. Landscape changes have become the most significant feature of this fragile zone. Landscape process model has already become an important means for the further development on the research of landscape changes, and its importance is recognized increasingly. Costal wetland is kind of a highly complicit landscape system, with dynamic changes. The muddy coastal wetland in Yancheng is one of the most typically primitive coastal wetland for its significant strategic position in global biodiversity protection. Over the years, under the influence of the nature and human socio-economic development, the wetland landscape structure and function changed dramatically. In this case, constructing a landscape process model could be used to explain spatiotemporal dynamic change process of the wetland landscape on mechanism. The article divides the core area of Yancheng National Nature Reserve into two patterns: the human-managed one and the natural one. According to the landscape material and wild's ecological monitoring data of 2000, 2006 and 2011, the costal wetland landscape process has been constructed, and the outcome is as follows: 1) Substituting space for time, combined with grey relational analysis, it concludes that the key factor that influences costal wetland landscape change is the soil salinity and moisture. 2) Using artificial neural networks can achieve the space distribution of the soil salinity and moisture, meanwhile, through layer overlay and hierarchical statistical method, it figures out the scope of threshold value and change rules of the soil salinity and moisture. 3) Constructing costal wetland landscape process based on the key ecological process with the GIS-Matlab-CA technology and inspects its overall precision, Kappa coefficient and consistency, it turns out that the concordance rate of spatial location finally determines the accuracy of the whole landscape simulation. 4) Use the founded model to predict the outcome of 2012-2020 and 2025; it forecasts that the tendency of reed swamp, spartina marsh expansion and salsa swamp decrease in Yancheng costal wetland will become much more obvious.

Key words: ecological processes, landscape model, coastal wetlands, Yancheng Natural Reserve