Assessing the Ecological Environment around the Yellow River Delta Area by RS and GIS

Mr. Ma Hui

Abstract

Regional ecological and environmental problems have become important issues to face and to solve urgently. As one of the most active regions with changing land and sea boundaries, the Yellow River Delta has a rapid and complicated evolution of its ecological environment. So it is very important

to evaluate the ecological environment in the Yellow River Delta.

In this MSc research, Remote Sensing (RS) and Geographic Information Systems (GIS) are used to build the index system for ecological environment synthetic evaluation. The ecological environment synthetic evaluation (EESE) model was applied to analyze the conditions and spatial differences of the ecological environment in the Yellow River Delta. The main findings can be summarised as follows:

(i) the Analytic Hierarchy Process (AHP) model was selected to evaluate the ecological environment in the Yellow River Delta; a raster cell of 25m×25m was regarded as the basic assessment unit.

(ii) the ecological function regionalization is based on the ecological environmental situation, ecological sensitivity and ecological service of the Yellow River Delta; the study area is divided into fifteen ecological function sections.

(iii) the factor index system for the synthetic evaluation of the ecological environment was based on regional characteristics of the Yellow River Delta, and was composed of five subsystems (ecological diversity index, vegetation coverage index, fresh wetland index, salinization index, and the incoming water quantity index).

(iv) after extracting the factor index from the RS image and evaluating the ecological environmental quality in the Yellow River Delta by the AHP model based on the raster cell, countermeasures were suggested based on the change in factor index.

The research results have shown that dramatic spatial differences of ecological environmental conditions occurred in the Yellow River Delta. By comparing the status of 1986, 1996, and 2001, the trends in ecological environmental quality seem to have been better and more stable in the inland study area, but poorer along the coastal area because of the inappropriate landuse, less water from the Yellow River and increasing industrial activity along shore.

Keywords: Ecological environment; synthetic evaluation; ecological function regionalization; Yellow River Delta; Remote sensing(RS); Geographical information system (GIS)