Study On The Major Environmental Factors Dynamic Change Of The Yellow River Estuary Based On RS

Estuary usually refers to ecological crisscross belt between river ecosystem and marine ecosystem. The estuary ecosystem is an integral system consisting of freshwater ecosystem, marine ecosystem, freshwater-seawater mixing ecosystem, tidal flat wetland ecosystem, estuarine island and wetland ecosystem. Estuary,as a heartland of human activties around the world, are characterized by multiple and plentiful natural resources,and special geographical locations. With the rapid growth of population and economy in coastal zones, the estuary ecosystem is brought to increasing pressures. The issues of resources exhaustion, ecological deterioration and environmental pollution have been getting worse. As a result, estuary relevant question has become one of the current research focuses; the protection of estuary resources, development and utilization is increasingly appealing to many experts, and management attention from home and abroad.Remote sensing techniques are utilized more and more often in water monitoring and playing an important role in spot investigation, data processing, experimental Simulation, model construction. Using the remote sensing techniques to monitor estuary ecological environment for a long period brings great convenience.Yellow River estuary is an important ecological zone in the world because of the advantageous geographical position and historical changes, which made an excellent environment for various marine organisms to grow. It is a typical estuary and wetland ecosystem, and it has abundant resources. It is essential for human survival and development to have a healthy ecosystem. But during the last hundred years, great many changes have taken place for yellow river esturary under the natural and human factors.The research area is adjacent to estuary of Yellow River delta. Major environmental factors Information from MODIS and TM remote sensing data are extracted. In this paper works that has carried out are as follows:(1)This paper extracted information of wetland in yellow river delta based on Landsat TM remote sensing data, and analyzed the character of quantity and spatial changes of wetland(2)This paper extracted information of coastline in yellow river delta based on Landsat TM remote sensing data, and analyzed the character of quantity and spatial changes of coastline.(3)This paper extracted information of SST in yellow river delta based on EOS MODIS remote sensing data, and analyzed the character of quantity and spatial changes of SST.(4)This paper extracted information of SSC in yellow river delta based on Landsat TM remote sensing data, and analyzed the character of quantity and spatial changes of SSC.In this paper suggestions have been given as follows:(1)The results show that from 1986 to 2009, areas of Artificial wetland increase initially and decrease afterwards, the increase rate has increased from 4% to 33.61%, and the total area increased by 69554.34hm2. The area of natural wetland has decreased by 45594.72 hm2 from 1986 to 2009, area of flats wetlands and salina wetlands decreased by 20729.70 hm2, 12256.83 hm2 respectively. And wetland salinization has aggravated.(2)There are three stages for the change of coastline: from 1986 to 1996, the coastline extends towards southeast, and increase rapidly. From 1996 to 2000, the course of Huang River were changed, a new sand spit siltation build up, the primitive sand spit receded. From 2000 to 2005, the extension and recede of coastline alternated, the change of coastline was not clear. From 1986 to 2009, the total trend of coastline length and area increased.(3)Yellow River Estuary and with a clear seasonal distribution of SST, Estuary was higher than the adjacent waters,SST from the coast to the open ocean declined gradually in spring from 2003 to 2009.Annual variation of SST fluctuations are obvious. The general trend decreased, but not significant.(4) From 1986 to 2009, SSC increased first and then decreased, and sediment concentration maintain at high level in Estuary waters. SSC from the coast to the open ocean declined rapidly.(5) It's beneficial to enhance the ability of information extraction with hierarchical classification and decision tree model. And it's an effective classification method for complex features.