The Study On Change Of The Yellow River Delta Coastal Under The Influence Of Human Activities

Coastal wetlands are an important and unique ecosystems on the planet-that locates in the transition zone between terrestrial ecosystems and aquatic ecosystems, and is one of the most important living environment of human beings .Coastal wetlands are the most severely damaged ecosystems which are subjected to human activities, their biodiversity diminishes day by day, it leads to the degradation of its function. So carrying out the research about dynamic changes of coastal wetlands is very important significance for coastal wetland conservation and sustainable use. However, the coastal wetland ecosystem mostly has the characteristics: for most coastal wetlands ecosystems, it is difficult to approach and measure directly from the ground; for most types of coastal wetlands, it is hard to field trips. So it is the most ideal approach to combining the remote sensing (RS) and geographic information system (GIS) technology to survey coastal wetlands resources and to study the dynamic changes.This paper takes coastal wetlands of the Yellow River Delta as study area, chooses the Landsat TM and ETM+ remote sensing image of studying area in 1992,1999, 2006 as the main data source, and gets the information on remote sensing of coastal wetlands though by geometric correction, band selection, pre-cut and other means of access to remote sensing images. Based on summarizing the previous classification of wetlands, proposes classification scheme of coastal wetland in the Yellow River Delta. Combined with relevant thematic information and survey data, carris out interactive interpretation in the study area of coastal wetlands, extracts wetland in formations, statistics the distribution and area of the wetland in the study area by using GIS technology. The paper also uses the software Fragstats3.3 on the results of landscape pattern indices by remote sensing image interpretation, and analysis the results of landscape pattern, the analysis shows: due to human activities and other factors influence ,from 1992 to 2006, the number of wetland landscape patches in the study area of coastal wetlands increases from 82 in 1992 to 240 in 2006; wetlands increasing patch density increases from 0.0674 in 1992 to 0.1973 in 2006; diversity index increases from 1.7826 in 1992 to 2.0933 in 2006; uniformity index increases from 0.6950 in 1992 to 0.7932 in 2006, these different degrees changes of indices reflect increasing degree of fragmentation in wetland landscapes, wetland landscape pattern is more dispersed, and also reflect the increasing influence of the human activities in study area of coastal wetlands. Through the study of the probability transition matrix of the study area,the landscape changed strongly.Finally, combining the above results, this paper specifics human activities on the study area of coastal wetlands change, the human activities of this paper include the pressures of population growth, the port's construction, oil field development, wetland restoration and the use of the upstream reservoir to the water and sediment regulation test, through those analysis of the impact of human activities ,discusses how to protect coastal wetlands resources better and reduce the human development and use of the unreasonable, takes some necessary means to promote coastal wetlands restoration and protection.