Evaluation Studies, Based On The Citygreen Model Urban Forest Ecological Benefits

The urbanization is the certain tide of our society development and it is also the important symbol of sustaining development. Nowadays, over 50% people in the world live in cities. The urbanization not only brings good things to society, but also causes a serious of problems such as deleterious gas, dusts, smoke and noises, etc. So the city residents press for having enough urban forests, because we all know that urban forests can improve the ecological environment of the city and promote the harmony between people and nature. Thereby, the studies on benefits of urban forests have become played a important and have aroused the countries attention.Since the near decades, the GIS technology has a great development as a support of the so called digital globe. The technology is based on the geography spatial data base; provide all kinds of spatial and dynamic geographic information by means of earth simulating. It supports the spatial and visual decision-making and also provides a brand new platform for the study on eco-benefits of urban forests.The article measure the eco-benefits of urban forests in different scale based on the GIS technology. The main information sources are the aerial photo of Shanghai green belt and western campus of Shanghai normal university. The result is below:1) The big scale study and small study scale both have the advantages and disadvantages. During the study we can select the right scale according to the study area, remote sensing images, fieldwork, time and expense consuming.2 ) The CITYgreen model combines the spatial and attribute information based on the study of the land use. The model is easy to query and verify, and it also run quickly. The model can also the scientific basis of decision-making.3) The Shanghai green belt sequestrates carbon 13.06 tons per year; the whole storage reaches 1677.33 tons which amount to 2165433.03 Yuan. The green belt removes air pollution 338234.1 pounds per year which amount to 6664737.04 Yuan.4) The western campus of the Shanghai Normal University sequestrates carbon 0.031 tons per year, the whole storage reaches 1.53 tons which amount to 1975.23 Yuan. The campus removes air pollution435.71 pounds per year which amount to...