Quantitative Assessment And Map-making On Ecosystem Services Supply,demand And Flow Of Carbon Storage And Water Supply Based On SPANs Model

Taking the region of South Line of Yellow River Diversion Project,Pianguan county and Hequ county,Wuzhai county,shenchi county,ningwu county and jingle county as study area,as study area.Using the remote sensing images,meteorological hydrological data,soil,land use types and other data,the supply of carbon storage and water supply were computed by InVEST model.Using the population,carbon emission per capita,industrial and agricultural water consumption,and other social and economic statistics,the demand of carbon storage and water supply were computed.The balance of supply and demand were analyzed and mapped.On the basis of this,the services flow path and the quantity of service flow were analyzed by the SPANs model,in order to provide the theoretical basis for the ecological compensation and the effective and scientific management of the ecosystem.The results were elaborated as follows:(1)The supply area of the carbon storage service was chiefly distributed on the vegetation area,forest and grassland in the study area.In 2000,2005,2010 and 2015,the supply of carbon storage services were 1458.98(10~4 t)?1457.12(10~4 t)?1454.20(10~4 t)and1452.58(10~4 t),respectively.The carbon density values were 1257.76(t/km~2),1255.93(t/km~2),1253.34(t/km~2)and 1252.01(t/km~2),respectively.There was no significant change in land use types,so,the supply of carbon storage services was basically stable during the 2000-2015period.The quantity supplied of carbon storage service was the highest in Ningwu county,while,lowest in Hequ county.The demand area of the carbon storage services were chiefly distributed on the carbon emission area,includes natural and man-made sources of carbon dioxide emissions.Taking residential sites,livestock farms,farmland and factories as the demand area of the carbon storage services in the study area.In 2000,2005,2010 and 2015,the demand of carbon storage services were 1074.06(10~4 t)?1221.12(10~4 t)?1317.51(10~4 t)and 1417.59(10~4 t),respectively.The demand was increased year by year,which was mainly affected by the increase of industrial carbon emissions.The quantity demanded of carbon storage service was the highest in Hequ county,while,lowest in Shenchi county.The quantity demanded of carbon storage services exceeded the quantity supplied in Hequ county,Pianguan county and Shuocheng county.However,other areas could achieve the carbon balance between quantity supplied and quantity demanded.The flow path of the carbon storage services was basically determined by prevailing wind direction.In 2015,the flow of the carbon storage of Shuocheng county,Hequ county,Ningwu county and Pianguan county were larger,while,the flow of the carbon storage of Shenchi county,Wuzhai county and Jingle county were smaller.In fifteen years,the flow of the carbon storage of Pianguan county was almost unchanged,the flow of the carbon storage of Hequ and Wuzhai counties have decreased,and the other counties have risen secondly.The maximum growth rate for the Shenchi county,Shuocheng county secondly.(2)Farmland that was irrigated by surface water,which the supply area of the water supply services was the location of pump station and river sluice.The supply area of farmland that was irrigated by ground water,livestock breeding and factory was replaced by the location of the machine well.The supply area of residential water use was replaced by the location of the waterworks.In 2000,2005,2010 and 2015,water production volume were8.47(10~6 m3)?10.79(10~6 m3)?18.23(10~6 m3)and 12.09(10~6 m3).The supply of water supply services increased first and then decreased from 2000 to 2015,which was mainly influenced by the change of precipitation.The supply showed a trend of decreasing from the center to the edges,in space.The quantity supplied of water supply services was the highest in Jingle county,while,lowest in Shuocheng county.The main beneficiaries for water supply services include:farmland,people,large livestock farms and factories.In 2000,2005,2010 and 2015,the demand of water supply services were 10.75(10~8 m3)?18.76(10~8 m3)?32.67(10~8 m3)and 35.98(10~8 m3),respectively.The demand of water supply services was increased year by year,which was mainly affected by the increase of agricultural irrigation,industrial production and livestock products.The quantity demanded of water supply services was the highest in Shuocheng county,while,lowest in Ningwu county.The contradiction between supply and demand of water supply services in each county was prominent,Shuocheng county was the most prominent,which perhaps because of the relatively high level of economic development and the most densely populated population.The flow of water supply services was a composite service flow.The services flow path was determined mainly according to the farmland irrigation network and the water pipeline.