Processes of wetland landscape changes in Naoli River Basin since1980s
20世纪80年代以来挠力河流域湿地景观变化过程研究

Naoli River Basin,with a total area of2416700ha,is one of the largest basins in the Sanjinag Plain.The basin is rich in wetland biodiversity,especially in wetland landscapes,ecosystems and communities due to the physical conditions.But,since the beginning of the founding of the P.R.China,large scale land reclamation activities had happened for a few times.Especially at the rapid economic development period after1980,China has put economic reform and opening policy into practice.As a result,great changes had occurred in wetlands.The natural wetland area decreased from533200ha in1982to171700ha in2000,or reduced by67.8%,and paddy field area increased138200ha or39.43times of that in1982.Dry farming land area also increased from969100ha in1982to1363400ha in2000,an increase of40700ha.Now the Naoli River Basin has become an important national grain production base from the previous"great northern wildness".This paper explores the process of wetland landscape changes over the past20years based on remote sensing and GIS techniques,particularly,wetland landscape classification system.And temporal and spatial land use/land cover changes are emphasized to analyze the relationship between land use and wetlands.