| As an important geographical and ecological barrier in China,Qinling Mountains has extremely significant scientific research value.In order to solve the ecological environment problems in the Qinling ecological functional area,assist the managers to implement appropriate management countermeasures,and realize the mutual coordination between the ecological protection and the economic development,this article studies in Qinling area.Based on the remote sensing,the meteorological and soil data,the spatial and temporal changes of landuse in 2005,2010 and 2015 was analyzed.The LCM model was used to predict the landuse in 2015,and the model accuracy was verified by comparing with the actual landuse.Then,based on the four future climate change scenarios proposed in the fifth assessment report of the IPCC,this model was used to predict the landuse in each scenario in 2030 and analyze its spatial change.Based on the CASA,RUSLE and In VEST ecosystem service models,three ecosystem services,including the carbon sequestration,the soil conservation and the water production,were evaluated in the study area in 2005,2010,2015 and2030 under four climate scenarios,and their spatial heterogeneity characteristics were analyzed.Finally,correlation analysis was used to further quantify the relationship between each ecosystem service.The results of the study are as follows:(1)The forestland was the most important landuse type in the Qinling Mountains,accounting for more than 40%of the total area,followed by the grassland and the farmland.The total area of the farmland,the grassland and the forestland accounted for more than 92%in the study area.From 2005 to 2015,there were significant changes in the area of each landuse type.The area of the farmland and the grassland increased first and then decreased,while the area of the forestland,the water and the building decreased first and then increased.The change range of the unused land was the largest and the area showed a sharp decline.(2)There was an obvious difference among the areas of each land type predicted under the four climate scenarios.Under the scenario of the RCP 8.5,the area of the farmland was the largest,which was about twice that of the scenario of the RCP 2.6,reaching 4,844.44 km~2.The expansion of the farmland area mainly concentrated in the northeast and the southwest of the study area.The forest area was the largest in the RCP4.5 scenario,which was 41318 km~2,mainly converted from the grassland.Under the scenario of the RCP 2.6,the area of the grassland was the largest,which was 11044.63 km~2.The increased area of the grassland mainly concentrated in the middle of the relatively low elevation.(3)From 2005 to 2015,the carbon sequestration in the Qinling mountains decreased first and then increased,and the spatial distribution pattern changed significantly.The capacity of the carbon sequestration was as follows:forestland>farmland>grassland>other landuse types,and the forestland contributed the most to the total carbon sequestration of the Qinling Mountains.The soil retention showed a trend of gradually decreasing from 2005 to 2015.The spatial distribution pattern of planting soil in Qinling mountains was basically stable in 2005 and 2010.In 2015,the areas with high carbon sequestration concentrated from the southeast to the central and western regions,which was the forest areas with higher elevations.The capacity of the soil preservation was as follows:forestland>grassland>farmland>other landuse types.From 2005 to 2015,the water yield of Qinling mountains increased first and then decreased.The spatial distribution pattern was relatively stable in 2005 and 2010.In 2015,the range of high-value areas was significantly reduced,mainly distributed in the major residential areas and the crop areas in the southwest,and scattered in the cultivated areas in the northeast.The capacity of the water production was as follows:other landuse types>farmland>grassland>forestland.(4)In 2030,the distribution characteristics of the three kinds of ecological services under four climate scenarios were basically the same as that in 2015.There were obvious differences in ecological services under each scenario.Carbon sequestration was the largest under the RCP 4.5,reaching 82.06×10~6 tons.Soil retention was maximum in the RCP 6.0 scenario,reaching 126.65×10~7 tons.The maximum water yield was147.56×10~8m~3 under the scenario of the RCP 6.0.The ecological services of the same landuse in different scenarios were significantly different,which corresponds to the change of the landuse.(5)From 2005 to 2010,from 2010 to 2015,and from 2005 to 2015,the relationship between the three ecosystem services was basically consistent.The carbon sequestration and the soil conservation showed a weak trade-offs relationship,the carbon sequestration and the water production showed a strong trade-offs relationship,the soil conservation and the water production showed a synergies relationship.The relationships among the carbon sequestration,the soil conservation and the water production in 2005-2010were different for different basins.The relationships between the three ecosystem services in each basin in2010-2015 and 2005-2015 are similar to the global scale.There were significant differences in the relationship among the farmland,the forestland and the grassland.The relationship between the ecosystem services in forestland was consistent with that in the global scale.From 2005 to 2010,the relationship between the carbon sequestration and the soil conservation,or the relationship between the soil conservation and the water production was different from that under the global scale.The carbon sequestration and the soil conservation showed a weak synergies relationship,meanwhile,the soil conservation and the water production showed a weak trade-offs relationship.From 2005 to 2010,from 2010 to 2015,and from 2005 to2015,the relationship between ecosystem services of the grassland was basically consistent,but the correlation between the carbon sequestration and the soil preservation was contrary to that of the global scale,showing a synergies relationship.(6)The trade-offs/synergies of the ecosystem services in the four IPCC climate scenarios were similar to those in 2005-2015.Among the five basins in the Qinling Mountains,the degree of the correlation relationship of the three ecosystem services in Nanluo river was relatively high in each scenario,and the degree of the correlation relationship of the services in each watershed fluctuated to a certain extent with the change of the scenario.The relationship between the ecosystem services of the farmland and the forestland in each scenario was similar to that of the global scale and that of 2005-2015.The trade-offs/synergies relationship of the grassland in each scenario was similar to that of 2005-2015.The relationships between the soil conservation and the water production,the carbon sequestration and the water production of grassland were basically consistent with the global scale,while the relationships between the soil conservation and the carbon sequestration were different with the global scale,indicating a weak synergies relationship. |
PDF Full Text Request