Net Primary Production Of Urban Vegetation Ecosystem In Shanghai

Vegetation,as an indispensable factor of the terrestrial ecosystem,plays an important role in global change. Vegetation Net Primary Productivity(NPP) is helpful to studying carbon cycle,carbon trend and carbon balance on the earth , and its sensitivity is also important to global climate. With the rapid development of RS,GIS and cyber-technology,the study by using remote sensing for NPP hastens maturely. It can monitor NPP of vegetation in a large scale fast and evaluate the productivity of the plant community in natural environment combined with these technology. So it can provides important basic information for decision department .This study aimed to explore NPP tempo-spatial patterns of Shanghai urban vegetation ecosystem by process-based model as 2006 for example. For the research purposes,Shanghai urban vegetation database have been set up,and a photosynthesis-production model have been made by VB process language consulting with TREEDYN model and TREEDEV model. With supports of database and photosynthesis-production model , net primary production (NPP)of Shanghai urban vegetation ecosystem have been quantified generally and quantificationally. With the support of the GIS technology, the kriging interpolation method was used to calculate Shanghai urban vegetation NPP .The estimated results have suggested that:1. The vegetation's digital map of different function region of Shanghai has been made,this is a basic work of this thesis. This paper used ArcGIS Desktop 9.2 software to interpret Shanghai aerial imagemap which scale is 1:5700 .The result shows that: the green land area of Shanghai is 139.11km~2, the percentage is 20.2%;the area of park green land, residential green land, accessory green land, road green land, water-side green land and procreative green land is 18.46km~2,34.22km~2,56.28km~2,16.17km~2,3.36km~2,10.62km~2 respectively,the percentage is 13.27%,24.6%,40.46%,11.62%,2.41%,7.63% respectively.2. Based on the vegetation parameters in Shanghai as state variables , several years average weather data as driving variables , urban vegetation NPP in Shanghai was calculated using Photoproduction simulation model. The species which was used in simulating was constructive species of every community types and they are Cinnamomum camphora,Platanus acerifolia,Metasequoia glyptostroboides,Cedrus deodara,Nerium indicum,Prunus cerasifera,bamboo respectively. The NPP of unit area varys depending on different vegetation. NPP of seven vegetations increase in turn:evergreen coniferous forest