Study On Habitat Change Of Ciconia Boyciana In Tianjin

Wetland is a significant habitat for Ciconia boyciana. In recent decades, there has experienced great change in wetland landscape of Tianjin due to the influence of human activities and natural factors, which results to lessening wetland area, degrading ecological function and regional economic development is restricted. Meanwhile, it has badly influenced the change of wetland habitat for birds, leading to huge disturbance on migration and reproduction of birds on wetlands.The paper takes Tianjin as study area. Three phrases of ETM/TM remote sensing images of 1999, 2003 and 2007 are used to do information extraction and classification of wetland by using the technologies of remote sensing and geographical information system. Each element of habitat of Ciconia boyciana has been classified by certain method to acquire the type map of pleasant habitat for Ciconia boyciana in Tianjin. Then, landscape ecology and remote sensing software are applied to make analysis on landscape pattern indexes and dynamic degree. In addition, areas of landscape patches on pleasant habitats are classified, and these patches are analyzed of influences regarding temporal and spatial change of size, quantity and shape on the habitat of Ciconia boyciana. The results are as follows:Firstly, the main factors that change the habitats of water birds are the interactive consequence of nature, human society and economy. In the four habitat elements of disturbance, water, food and hidden object, the change of disturbance factor is the source and basis that brings the change of three other factors. That is to say, the comprehensive function, composed of disturbance factor and other natural and social factors, leads to the change of three other factors.Secondly, the combination of habitat factors brings out the pleasant habitat map of Ciconia boyciana. The software of FRAGSTATS is used to calculate the landscape pattern indexes of pleasant habitat types. In addition, remote sensing software is applied to do transfer analysis of habitat types of Ciconia boyciana. The dynamic model is used to analyze the dynamic change trend of pleasant and unpleasant habitats.Thirdly, landscape patch map is applied to make analysis on the patch area, number and shape of pleasant habitats of Ciconia boyciana. It is found that large area of patches that are suitable for the survival of Ciconia boyciana are with complicated shape and lessening area. Degree of fragmentation of patches is rather severe, which has already influenced the habitat quality of Ciconia boyciana, leading to the less number of Ciconia boyciana. Therefore, scientific and reasonable protection and recovery measures should be taken as soon as possible.