Study On Land Use And Ecological Carrying Capacity Of Tianfu New District Based On Geological Environment

The dynamic changes of land use and ecological carrying capacity are affected by geological bearers.The land use and ecological carrying capacity of the rapidly urbanized areas have changed drastically nowadays.The influence of geological factors and the main driving forces in the process of change have yet to be clarified.If the impact of geological environment on the dynamic changes of land use and ecological carrying capacity can be solved,it can help to solve problem of ecological and land use couse by the rapid urbanization process for Tianfu New District,a new disrict which have complex geological environment.Sichuan Tianfu New District is a national-level new district established by the Party Central Committee and the State Council.In recent years,it has maintained a strong momentum of rapid development.Infrastructure construction has been advancing rapidly,urban functions have been accelerated,and human-land processes are strongly coupled.From the perspective of geological environment and national spatial planning,etc.The land use and ecological carrying capacity of the Tianfu New District help to identify the mechanisms of different systems in the process of rapid urbanization.Based on multi-source and multi-phase remote sensing data,using software platforms such as Arc GIS and e Congnition to extract six of Tianfu New District in 1988,1997,2003,2009,2014,and 2016 Land use and geological environment information was established during the period,and a database of dynamic land use and geological environment was established.Based on land use change,landscape pattern change,driving force of change and other factors,the Markov model is used to predict the change trend.At the same time,the ecological carrying capacity of Tianfu New District is studied.The analytic hierarchy process(AHP)is used to analyze the ecological service function level of Tianfu New District.Combined with the geological environment of Tianfu New District,the spatial distribution law of possible problems and ecological carrying capacity in the process of land planning is analyzed.This paper has achieved the following results:(1)The geological conditions of Tianfu New District are complex,and the geological environment plays an obvious role in restricting the spatial distribution of land use and ecological carrying capacity.From the perspective of geological environment conditions,the Longquanshan fault zone and the Huanglongxi-Zhengxing fault zone in the area are distributed in the northeast direction,which is the main framework of the structure and geomorphology of the study area.Among them,the Longquanshan fault zone affects the eastern part of the study area,with obvious tectonic activity trails,many woodlands and grasslands in the affected area,and a good ecological carrying capacity.The stratigraphic composition is mainly Quaternary,distributed in the east and west of the study area,and the land use types are mainly urban village construction land and cultivated land;the Cretaceous and Jurassic strata,which are basically consistent with the spatial distribution of geological structures,Cretaceous strata Mostly forest land.In addition to geological structure and stratigraphic lithology that have strong constraints on the land use type and the spatial distribution of ecological carrying capacity,topographic factors play a significant limiting role.Low-altitude areas are mostly urban and rural construction land,cultivated land,etc.,and the ecological carrying capacity is average;high-altitude areas are mostly woodland grassland,which has a higher ecological carrying capacity.(2)The land use change in Tianfu New District was significant between 1988 and2016.The overall change rate of land use types in the study area reached 52.35%,and the total change area was 826 km~2.Among them,the construction land of urban villages extends from Dongsheng Street Office,Xihanggang Street Office,Huayang Street Office and Longquanyi District around Chengdu to Huangjia Town,Yongan Town,Zhengxing Town,Xinglong Town and Baihe Town.The area of cultivated land in this area has decreased significantly,and the controlled strata are mainly Quaternary strata;the forest land resources in the east and south have been affected by the expansion of cultivated land,and the area has decreased.Because the Jurassic and Cretaceous strata are not suitable for cultivation,human activities are relatively small.Cultivated land erosion is limited.In summary,urban and rural construction land and cultivated land change greatly,of which about 38% of the original cultivated land area becomes urban construction land;urban village construction land and transportation land expand rapidly,and their area expansion degree indexes are 35.5 and 10.1,respectively.The study of landscape pattern shows that the proportion of the largest patch of urban village construction land occupied by the landscape area increased from 0.29% to8.67%,becoming the most intense landscape type in the study area.The proportion of forest land decreased from 67.36% to 37.46%,and the shrinkage was more obvious.The landscape spread index showed a downward trend year-on-year from 75.68% in1988,and remained at around 62.35% after 2009,indicating that the rate of change of the landscape pattern in the new area is changing from fast to slow.The number of landscape patches increased from 2253 to 3179,indicating that the land use types in the study area are becoming more diverse;and the Shannon evenness index increased from0.8 to 1.26,indicating that the landscape distribution has become more uniform.According to the analysis of the dynamic changes of geological environment,land use types and landscape patterns,it can be known that geological factors are the basic controlling factors for land use types in Tianfu New District,and socioeconomic factors and policy factors also have a role in promoting changes in land use types.According to the land use evolution characteristics and driving mechanism,the Markov model is used to predict the future land use change in Tianfu New District.The results show that urban and rural construction land in the new district will become the most important type of land,wetland,landscape land will increase,cultivated land and forest Wait for it to degenerate.This is also in line with the goal of the Tianfu New District to build a "park city" demonstration zone.(3)Constructed an evaluation system for the ecological carrying capacity of Tianfu New District.Three sub-target layers of ecological support,ecological pressure and ecological elasticity are selected to evaluate the ecological carrying capacity of the new area,and two indicators of biodiversity and biological output are selected to evaluate the ecological service function.The research results show that with the acceleration of the urbanization process in the study area,the area of ecological land in the area has gradually decreased,the vegetation in some development zones has degraded,the pressure on the ecological environment has gradually increased,and the spatial distribution of ecological service functions has obvious geographical features.But at the same time,in recent years,the Provincial Party Committee and Provincial Government and the Chengdu Municipal Committee and the Municipal Government have seriously implemented the Party Central Committee's deployment requirements for strengthening ecological civilization,adhered to the "green water and green hills are the golden mountains and silver mountains",adhered to the concept of building a "park city",and seriously implemented the plan Reforestation policies,speed up the construction of urban wetlands,greenways and waterfront spaces,and vigorously develop a green and low-carbon circular economy.The urban green space area in the new area continues to increase,the vegetation coverage rate has increased,the ecological land area has stabilized,and the ecological carrying capacity and ecological service functions remain at a high level.In the end,this study concluded that the geological environment in Tianfu New Area is relatively stable at present,and it has a weak restriction on the ecological carrying capacity and ecological service functions in the region.The main driving force for the evolution of ecological carrying capacity and ecological service functions is the rapid urbanization process Human activities.(4)Identified the mechanism of the geological environment's effect on the evolution of land use and ecological carrying capacity.Through factors such as engineering geology and hydrogeological conditions,the impact of geological environment on land use and ecological service functions is analyzed.The research shows that the current geological environment's impact on the land use and ecological carrying capacity of Tianfu New Area is mainly to control the spatial distribution of land use and the spatial distribution of vegetation types.Among them,the engineering geological environment and geomorphic factors have a strong control effect on the spatial distribution of land use,while the hydrogeological environment and engineering geological environment have an indirect constraint on the ecological service function and ecological carrying capacity of the study area.The geological environment of Tianfu New District is relatively complex,and the impact of geological environment on ecological carrying capacity must be fully considered during the rapid urbanization process.The research in this paper has a unique reference to the spatial planning and development of territories with similar characteristics.