Estimation And Change Of Ecosystem Service Value Of Typical Dike-pond In The Pearl River Delta

As one of the most typical ecological agricultural land,dike-pond has provided many ecosystem service functions for human society.Nowadays,with the loss of agricultural labor in dike-pond district,and urban expansion and occupation of real estate development,the original dike-pond’s area is shrinking year by year,the rapid development of industrialization,the sewage quality of the dike-pond caused by the enterprises in the area draining into the pond and the excessive intensive breeding of the dike-pond are seriously polluted,and the ecological security is facing a huge threat.Quantitative measurement of the value of the ecosystem services of the dike-pond can evaluate deeply the contribution of the dike-pond to the entire ecosystem and improve people’s awareness of the protection of the dike-pond.This article takes Foshan,the birthplace of the dike-pond in the Pearl River Delta as an example.Based on the analysis of the time and space evolution of dike-pond,it uses the market price method,shadow engineering method,and results reference method to serve the dike-pond ecosystem in 2000,2009,and 2017.The value is estimated,the change law is discussed in depth,and the driving mechanism is analyzed using the geographical detector model,with a view to providing scientific basis for the further development and sustainable use of the foundation dike-pond in the Pearl River Delta.The conclusions are as follows:(1)From 2000 to 2017,dike-pond were mainly distributed in the north and southeast in Foshan,with an area from 88139.26hm~2to 68894.79hm~2,and its proportion of the total land area decreased from 23.23%to 18.14%.It showed a negative change and the shrinking speed slowed down during the period;dike-pond mainly expanded to the north and southwest of Foshan,while the area in the southeast and east was significantly reduced;from 2000 to 2017,dike-pond turned out 35518.98hm~2,the main flow for urban and rural construction land,other land-use types were transferred to dike-pond for a total of16280.33hm~2,mainly cultivated land.(2)In 2000,2009 and 2017,the ecosystem services value of Foshan dike-pond was952.21×10~8yuan,582.97×10~8yuan and 708.73×10~8yuan,and the unit area values were108.03×10~4yuan/hm~2,75.41×10~4yuan/hm~2and 102.87×10~4yuan/hm~2showed a trend of decreasing first and then increasing.Among the individual functions,the adjustment of climate and material production functions contributed the most to the total value,and the contribution of soil functions was kept to a minimum.The value of material production functions increased the most during the period.It reached 48.60×10~8yuan,with an average annual growth rate of 6.15%,followed by tourism and leisure functions,with an increase of 39.14×10~8yuan,while the value of climate function adjustment decreased significantly.A total of 317.34×10~8yuan decreased during the study period,with an average annual change The rate is-2.17%.(3)From 2000 to 2017,the spatial distribution of the ecosystem service value of dike-pond in Foshan was significantly different.The higher-value towns(streets)were roughly along the line of"Leping Town-Southwest Street-Danzao Town-Xiqiao Town-Xingtan Town".Expanding to the southeast,the value of towns(streets)in the southwest and east is relatively low.In terms of changes,the value of streets in Hecheng increased significantly during the period,reaching 9.95×10~8yuan.Correlation analysis shows that Moran’s I of the ecological value of the basic ponds in the town of Foshan dropped from 0.5005 to 0.3472.The ecosystem service values of the dike-pond in 33 towns(streets)have significant spatial positive correlations and spatial agglomeration effects."High"clusters are distributed in the southeast and north of Foshan,from five to three.The"low-low"clusters are concentrated in Chancheng District,increasing from one to four,and the polarization effect is significantly intensified.From the perspective of individual functions,in terms of distribution,the largest material production value is always Xingtan Town,and the highest value for tourism and leisure is Nanzhuang Town.The remaining six individual functions are more uniformly distributed,with the first value in 2000,2009 and 2017.In turn,Xingtan Town,Leping Town,and Xingtan Town.In terms of change,the most significant increase in the value of material production is Xiqiao Town,which is the birthplace of typical dike-pond in the Pearl River Delta.Water,maintaining biodiversity,and maintaining soil values have all increased significantly.The value of tourism and recreation in Nanzhuang Town,near the central urban area of Foshan,has increased the most.(4)From 2009 to 2017,population status,regional economic development level and agricultural development level are the main factors that affect the spatial distribution of the ecosystem service value of the dike-pond,of which the population factor has the strongest influence;under the combined effect of any two influencing factors,the degree of impact on the evolution of dike-pond ecosystem service value is greater than a single factor.(5)Aiming at the four types of changes in the value of the ecosystem services of dike-pond in Foshan,the following sustainable development countermeasures are proposed:the management of strong and weak reduction areas should be strengthened to curb the continuous decrease of the base pond area,protect the base pond environment and reduce ecological risks;Relatively stable areas protect the safety of land use at the source,increase publicity,and arouse the public’s attention to the ecological function of the pond,and develop the leisure tourism function reasonably;growth regions need to increase investment in science and technology,and continue to increase the service value of the pond ecosystem.