Taking the buffer zone with the width of 10 km along the main stem of Nenjiang River as astudy area

based on the theories of landscape ecology

the influences on the stream restoration of landscape pattern changes of each individual type and the whole landscape were studied using Landsat images of 1976

1989

2000

2005

and 2008.The results showed that over the past 30 years

area of the water body of Nenjiang River decreased

extent of fragmentation of the landscape decreased

and the degree of meandering of the river decreased

all of which are not in favor of the restoration of biodiversity.The changes in farmland patterns exacerbated the deterioration of the water quality of Nenjiang River

and the changes in the whole landscape configuration did not favor the natural restoration of waters as well.However

since 2000

the changes in the forestland and wetland patterns to some degree favored the biodiversity restoration and water quality improvement of the river

as a result of the implementation of a series of ecological reconstruction policies and projects including returning farmland to forestland and grassland

planting tree and afforestation

protecting wetland.