Research On The Riparian Zone Landscape Patterns Of The Small Sanjiang Plain

This paper illustrates the significance and function of riparian zoneecosystem. It is a critical system that interfaces aquatic and terrestrialenvironments. It is sensitive to environment changes and has obvious edge effect.One of the leading causes of wetlands loss and ecological system functiondecreasing is that the riparian zone has been destroyed.It has abundance wetlands resources which play an important role formaintaining regional ecological environment in the small Sanjiang Plain.Short-term and high strength human activities are taken into account onwetlands spatial and temporal distributions on the perspective of riparian zone.Thus it contributes to make plans for protecting the riparian zone and wetlandsecosystem for the sustainable development.In the small Sanjiang Plain,4km width of the riparian buffer zones of themain rivers are analyzed quantitatively. Supported by remote sensing andgeography information systems, the land use structure of the riparian bufferzones is discussed respectively in horizontal and vertical scale from1986to2013. The theories of landscape ecology are needed not only to analyze thelandscape patterns, but also to define the appropriate width of the riparian zonein the small Sanjiang Plain. The main results are as follows in conclusion.Firstly, the land use structure in riparian buffer zones has been discussed inhorizontal and vertical scale from1986to2013. The results show that inhorizontal scale, marshes and waters are mainly distributed in0-1km sub bufferzones of rivers, especially within the distance of0.5km. Forest lands andfarmlands account for a large proportion within1-4km sub buffer zones ofrivers while residents and the grass lands occupy a small proportion. The values of land use comprehensive index show gradually that human activities on theriparian zone move towards rivers in recent years. In vertical scale, land usetypes distinguish with each other on the vertical distribution under differentelevations in the riparian buffer zones. Human activities lead to the increasingland use comprehensive index values under the elevations between40and60mafter2000.Secondly,5periods of landscape indexes of riparian buffer zones indicatethat within0-0.5km sub buffer zones of rivers marshes remain and concentrateintact that are the dominant landscapes with strong connectivity absolutely. Suchareas are essential for providing wildlife habitats and managing the developmentof riparian ecosystem sustainably with less human impact. In0.5-1km subbuffer zones of rivers the influence of human factors becomes larger that is whythe aggregation and connectivity of marshes, forest lands and waters turn to beweakened. Within1-4km of the buffer zones, human activities are weakeningto the influence of natural resources such as marshes. In1.5-4km sub bufferzones of rivers, cultivated lands are integrated together year to year.Thirdly, we suggest1km as the appropriate width of the riparian zone inthe small Sanjiang Plain on the perspective of landscape ecology. Within0.5-1km riparian zone, it is the tendency that marshes are converted dramatically byhuman activities. The protecting of such critical sites is significant to confirmthe sustaining development of riparian and wetlands ecosystem.