Urban Spatial Pattern Change And Its Effects On Ecological Service Values In Jinan City

The rapid urbanization and expansion of city as well as the constantly reconstruction of urban spatial structure have caused the massive loss of farmland, and the deterioration of ecological environmental quality, which accordingly have resulted in series of eco-environmental problems, such as greenhouse effect, soil erosion, water pollution and the loss of urban biodiversity. Therefore, the governments and scholars have paid much more attention on the urban land use changes recently. Ecological service value is the life support products and services, directly or indirectly provided by the structure, process and function of ecological system, which plays an irreplaceable important role on life support and the dynamic balance between support system and environment, and is of great practical significance to promote the economic, environmental and social coordinated development. However, in the urban area, rapid urban sprawl has caused more and more natural or semi-natural resources lost, and then brought the reducing of their ecological service value. As the urban sprawl is still going on, a further research needs to be done to predict the urban development and accordingly find its response of the ecological service value. The results will be important to guide the government to manage and plan the urban space growth and to keep the urban sustainable development.Taking Jinan city as the case study, the 1989,1996,2004,2009 land use maps captured based on RS, GIS software platform were used as the original data, firstly, the characteristics of land use changes from 1989 to 2009 were analyzed, and then the urban expansion process from 1989-2009 were simulated and reconstructed with the SLEUTH model. Then on this basis, three kinds of prediction scenarios were set according to the different intensity of ecosystem services value function protection, that is:current develop trend; farmland moderate protection; and ecological land moderate protection, and then the urban expansion under different prediction scenarios for the next 20 years (2010-2029) were simulated, respectively. Finally, according to the Chinese terrestrial ecosystem service value per unit area, combined with the sensitivity analysis of ecological service value, the existing nearly 20 years land cover data and the simulated future 20 years land cover data, the ecosystem services value were estimated quantitatively, at the same time, the changes of the ecosystem services value were also analyzed, at last, the potential influence urban space expansion on future urban ecological service value and the driving forces of urban ecosystem service value change were explored. The results will be important scientific basis and decision support for urban growth management and regional sustainable development. The main conclusions of this research were:1). During the past 20 years (1989-2009), the urban land use structure Jinan city has changed significantly, the built-up land area has increased by 100.69 km2 with an average annual growth rate of 2.91%; the green spaces and farmlands have decreased by 94.43 km2 and 8.78 km2, respectively,90.4% of which were replaced by the built-up land.2). The scale and speed of urban built-up land development are really different under the three different development scenarios:Scenario I (at current growth trends)> Profiles II (farmland moderate protection)> Profiles III (fusion strategy of landscape ecology). The results indicate that making the ecological sensitivity analysis and ecological network development as the core strategy of landscape ecology in the removed layer of SLEUTH model could effectively control the trends of green space and farmland to be occupied and then make the urban growth more rationally and scientifically.3). The analysis of ecological services value shows that the ecological services value in the past 20 years continued to decline, from ?248.65×106 in 1989 to ?205.79×106 in 2009, which is mostly due to the loss of the farmland and green spaces, accounted for 51.34% and 35.28% of the total reducing, respectively; among of the three prediction scenarios, Profiles ? (fusion strategy of landscape ecology) has the best protective effects on ecological system, which could effectively control the trend of ecological service value's reducing and protect the ecological environment.The purpose of this paper is to explore and simulate the land use changes in the past and future, and their response of ecosystem services value. We hope the research results could provide decision-making support for the urban growth management, planning, as well as social and economic sustainable development in the future in Jinan city.