Landscape Pattern And Influence Factors Around Surface Water In Horqin

Desertification is one of the important social-economy-environment issues the current global human beings are facing with. In the northern China, the desertification problem is serious and threatens the sustainable development of regional social and economic and ecological environment. The area around the surface water has the relative advantages of soil and water resources. There the social economic activities are centralized and so is the frequent desertification area. In recent years, with the development of social and change of climate, the mode and intensity of human activities have had the new changes. The research on human activity in area around water helps to reveal development trend and characteristics of the relationship between human and desertification in the typical area, which provide important basis of the desertification prevention and control in ecotone between agriculture and animal husbandry of northern China.The researches of landscape pattern have attracted a wide spread attention over the years, and it plays an important role in the thorough understanding of the variance of regional surface land and the man-land relationship. Based on this point, a study was conducted to explore the landscape fragmentation of nearly water area in Naiman Banner by using Landsat/TM data in1987,1992,1999,2004and2009. It extracted the landscape data through RS and GIS technology, and based on the analysis of the temporal and spatial variation, it discussed the relationship between the change of landscape pattern and desertification, and then revealed the influencing factors. The results are as follows:(1)Compared to the other areas, the landscape structure in the area around water was affected by human activities more deeply. At the patch level, cultivated land, grassland, forest land and sandy land had a higher area percentage, and a much higher degree of plaques fragmentation. From the landscape level, the landscape fragmentation degree was higher and landscape diversity was lower in the area nearly water. It suggested that the relationship between human and land near water was tenser and the intensity of land use increased.(2)From1987to2009, the landscape pattern in the area near the water changed a lot. The area of cultivated land, forest land and construction land kept sustainable grown, while grassland and sandy land decreased gradually. At the same time, the area of major landscape types was affected by surface water distribution obviously. Inside the area near water1-6km, there was a significant positive correlation between the cultivated land area percentage and its distance from the boundary of water. While between sandy land area percentage and its distance from the boundary of water, there was a negative correlation. And for grassland, the area percentage increased first and decreased then, with the increase of the distance from the boundary of water.(3)On the scale of landscape, the more closer from water, the higher value of PD、ED and CONTAG were. On type scale, the more closer from water, the higher value of PD and ED in cultivated land、grassland and forest land; While the value of PD and ED decreased gradually. That’s the landscape near water was more easily to be sharply cut to complex shapes, and distributed more scattered.(4)There was a close relationship between landscape pattern and desertification, and different landscape types made different contributions to land desertification. Among them, forest land was the most difficult and the unused land had the highest risk to be desertification. According to the composite index SI of landscape pattern, there was a high risk of desertification inside the area1-2km near water. At the same time, the more close to the surface water area, the landscape pattern changed more frequently, the degradation possibility is more higher.(5)Human factors had become more and more influential on landscape pattern in area near water. Under the stimulation of economic development, over-exploitation of land resources became the main reasons of land degradation and landscape desertification. Meanwhile, policy factors on the role of landscape changes could not be ignored. The policy conforming to the law of scientific growth and practical principle would play a positive role in the protection of eco-environment.