The monitoring of land degradation: the change of saline-alkaline land in Jilin Province of China

Jilin Province is a major distribution area of saline-alkaline land in China, which mainly distributes in the middle and west part of Jilin Province. By comparing the record in 1958 and in 1981, the area of saline-alkaline land increased greatly. The remote sensing image provided very useful information for the research of the change of saline-alkaline land. Through comparing remote sensing images in same season of different times, the change of saline-alkaline land can be identified. In the research, the Landsat TM images of 1980´s and 1990´s were used. Taking Landsat remote sensing information as the main source and use multi-time remote sensing information to analyze the change of the saline-alkaline land cover in Jilin Province of China in recent twenty years, we can get both quantity change and quality change of saline-alkaline land, which shows that the increasing trend of the saline-alkaline land cover in Jilin Province of China is obvious. By analyze the driving forces, we can see that natural conditions, such as climate change has part of role, but human activities, such as unreasonable land reclamation and over-pasturing are also the major factors.