The Contrast Study Of Oxygen Releasing Of Different Forest-soil Systems In Jingyuetan Forest Garden

At present, cities in the world develop very quickly. Population explosion and the scales of industrial production constantly increasing cause the decreasing of greenland area in the city and the worsening of ecological problems of city. City is the result of social productive developing and it is a high-level people settlement formed by many factors. It is the landscape infected and reformed by people intensely. Today, with the developing of human society, city has become the main location of people activity. City landscape is the crystallization of human civilization and society progress and it is the central issue of development and change of an era'economy, politics, society, science, cultural ecological environment. Statistic tells that 60% of pollution come from city, but area of city is 0.3% of earth only. City is not only the landscape where people consume the most of resource and energy, but also the important source of ecological environment pollution source. A country'sustainable development must pay attention to a city's sustained development. Without the sustained development of city's ecology, a country's ecology will not safety. The forest garden in city has many ecological functions. For example, release oxygen, water resources protection, regulating climate, aborbing pollution, beautify landscape, water and soil conversation etc. The forest vegetation around city aborb a lot of carbon dioxide, synthesize organic matter and discharge oxygen. This can adjust and improve the balance of carbon and oxygen in low level and improve the air quality in some areas. The forest vegetation plays an important role in improving the ecological environment in city. But the fixed quantity investigations of how to dispose the forest in forest garden around city and bring into play the comprehensive benefits of forest vegetation effectively are short. Base on the GIS, this paper option the forest garden of Jingyuetan as typical region. On the base of the forest landscape in Jingyuetan forest garden and looking into practice, author option different forest, the same forest with different age to measure the photosynthesis and respiration. Through that different forest, different forest age and different density community's net photosynthesis, soil respiration rate and generating oxgen rate can be getten. After correcting error of measuring value, author adopt statistics analysis and get the following conclusion: the different forest-soil system in Jingyuetan forest garden's contribution is different. Adult oak forest's rate of oxygen releasing is the biggest and over larch forest's is the smallest. This paper has six sections. The first is preface. The section is general situation of research region. The third section is general situation of experiment region and design of experiment. The fourth is the material of experiment and method. The fifth is outcome and analysis. The last one is conclusion and suggestion.