Spatial-Temporal Evolution Of Ecosystem Services In Guangdong-Hong Kong-Macao Greater Bay Area Based On CA-Markov And InVEST Models

The fifth report of the IPCC in 2014 pointed out that human activities are the main cause of global warming.The massive emission of greenhouse gases brings a series of problems such as high temperature stress,storms and extreme precipitation,flood disasters,and soil erosion.The current rapid urbanization in the Guangdong-Hong Kong-Macao Greater Bay Area will inevitably have a negative impact on the ecological environment,thereby threatening the ecological security and economic development of the Guangdong-Hong Kong-Macao Greater Bay Area.In order to avoid more expensive solutions in the future,based on the InVEST and CA-Markov models,this paper selects four indicators of habitat quality,carbon storage,water supply,and soil conservation to analyze the temporal and spatial evolution of ecosystem services in the Guangdong-Hong Kong-Macao Greater Bay Area from 2005 to 2018 Features and trade-offs and synergy between each other.This study uses the method of ecological economics to superimpose the unified dimension to obtain the comprehensive value of ecosystem services in the Greater Bay Area,and intuitively reveals the contribution of various ecosystem services to human well-being.Finally,based on the supply-demand relationship of ecosystem services,the study conducted ecological space control zoning in the Greater Bay Area,and proposed future urban development strategies under the control zoning.The research also predicts the changes in ecosystem services under different scenarios in the Greater Bay Area in 2030,providing reference for the application of ecosystem services theory in territorial and spatial planning,ecological security patterns,and sustainable urban development.The important conclusions of the study are as follows:(1)Habitat quality and carbon storage in the Guangdong-Hong Kong-Macao Greater Bay Area have been declining year by year.The rate of decline first slowed down and then increased.The fluctuation of soil retention decreased,while the “U”-shaped water supply increased.In terms of spatial distribution,the habitat quality is low in the central area and high in the surrounding area.Carbon storage is low in the central area and the east coast of Lingdingyang,and high in the surrounding area.The water supply is low in the central,northwest and eastern woodlands,and high in the northern and southwestern coastal areas.Soil conservation is low in the central region,and high in the southern coastal and northern woodlands.Habitat quality,carbon storage,and soil conservation are in a synergistic relationship.Habitat quality,carbon storage and water supply are in a trade-off relationship,and soil conservation has little correlation with water supply.(2)The total value of ecosystem services in the Guangdong-Hong Kong-Macao Greater Bay Area in 2005,2010,2015,and 2018 was 366.26 billion yuan,246.443 billion yuan,282.28 billion yuan,and 252.694 billion yuan,respectively,showing a downward trend in fluctuations.In terms of spatial distribution,the ecosystem service value of the Greater Bay Area is low in the central region and high in the southern coastal and northern woodlands.The economic value of soil conservation in the Greater Bay Area is the highest,followed by carbon storage and water supply,and the economic value of habitat quality is the lowest.(3)The Guangdong-Hong Kong-Macao Greater Bay Area presents an imbalance between the supply and demand of ecosystem services,and the imbalanced area accounts for 66.2%.According to the control zone,the Greater Bay Area will have three main development areas in the future: First,it will develop from the central part of Guangzhou to the north.The second is to develop along the central part of Huizhou towards Dongguan and Shenzhen.The third is the development of cities such as Zhuhai,Zhongshan,Guangzhou,Dongguan,and Shenzhen along the coast of Lingdingyang.Foshan,Zhongshan,Dongguan,Shenzhen and other central regions are key ecological restoration areas.The surrounding areas of Zhaoqing,Huizhou and Jiangmen are major ecological protection areas.(4)Compared with the current development scenario,under the planned protection scenario in 2030,land use changes are more reasonable,and habitat quality and carbon storage functions are improved.It shows that the spatial control zoning can promote the balance of supply and demand of ecosystem services in the Guangdong-Hong Kong-Macao Greater Bay Area,and the coordinated development of urban construction and ecological protection.