| The Loess Plateau is the most severe soil erosion area in China and globally,and is also the region with the most remarkable effects of global vegetation construction.Therefore,the systematic evaluation of various ecosystem services in vegetation restoration was a key link for ecological function improvement and sustainable development on the Loess Plateau.In view of this,based on the demand for environmental construction on the Loess Plateau,a database of vegetation and soil carbon sequestration,vegetation water capacity,soil water storage and soil and water conservation was constructed.This study systematically studied the evolution characteristics and regional differentiation laws of carbon sink,ecological and hydrological function,soil and water conservation under different vegetation restoration types（artificial trees,artificial shrubs,and abandoned grassland）through field survey sampling（267 plots）and literature data integration（537 plots）.Additionaly,this study revealed the resilience and driving factors among various ecological functions,and discussed the impact of vegetation restoration on the cultural ecosystem services in the region,which may provide a scientific basis for the functional enhancement and sustainable management of vegetation on the Loess Plateau.The main conclusions are as follows:（1）Vegetation restoration on the Loess Plateau significantly increased plant carbon sequestration and soil carbon stock（0-200 cm）.Compared with farmland,plant carbon sequestration and soil carbon stock significantly increased by 74.44%and 41.29%,respectively.For different vegetation types,the increased effect of plant carbon sequestration and soil carbon stock in Robinia pseudoacacia was the highest,which were 108.27%and68.65%,respectively.The improvement effect of vegetation restoration on both plant carbon sequestration and soil carbon stock increased with the restoration years and zonal rainfall.The soil carbon sequestration rate of grassland was higher than that of trees and shrubs,and was more significant in the soil layer of 0-20 cm.Vegetation restoration significantly increase soil carbon stock while increasing plant carbon sequestration during vegetation restoration.In addition,there was a significant positive correlation between shallow and deep layer in soil carbon storage,with each 1 Mg C ha-1 increased in soil carbon stock in0-100 cm and a corresponding 0.21 Mg C ha-1 increased in soil carbon stock in 100-200 cm.（2）Vegetation restoration on the Loess Plateau significantly reduced the yield of soil erosion on the slope,and vegetation was more effective in reducing the yield of sediment compared to regulating runoff yield.After vegetation restoration,the yield of runoff and sediment were significantly reduced by 72.38%and 80.76%,respectively.For different vegetation types,the Hippophae rhamnoides was the most effective types in controlling runoff yield,while there was no significant difference in the effect of different vegetation species in controlling sediment yield.The effectiveness of vegetation in controlling runoff and sediment yield increased with the restoration years.Similarly,vegetation had the greatest benefit in reducing runoff and sediment yield in areas with rainfall greater than 550 mm.However,the control of runoff and sediment yield by vegetation showed a trend of increasing and then decreasing with the slope,where the inflection points of runoff and sediment yield were 22°and 25°,respectively.The annual runoff and sediment yield were negatively correlated with vegetation coverage,vegetation biomass,soil organic carbon content,and soil moisture,while positively correlated with soil bulk density,clay and silt.In addition,vegetation can not only reduce the yield of sediment,but also regulate the surface runoff,and grassland was the best choice to optimize the trade-off between soil erosion control and surface water resources.（3）Vegetation restoration increased the water-holding capacity of plant,but caused a severe loss of soil water storage（0-500 cm）.Compared with farmland,soil water storage（0-500 cm）of forest,shrub and grassland decreased by 17.41%,20.47%and 7.21%,and the consumption of deep soil water storage by vegetation was the most serious.For different vegetation species,R.pseudoacacia and Caragana korshinskii had the highest consumption of soil water storage.In general,the water-holding capacity of plant increased with restoration years,which also increased the depletion of soil water storage.In addition,the consumption rate of soil water storage of forest and shrub was significantly higher than that of grassland,especially for deep soil water storage.According to the variation characteristics of soil water storage with rainfall gradient for different vegetation types,artificial trees and shrubs could be planted in areas with rainfall greater than 550 mm,while grassland was the optimal restoration type in areas with rainfall less than 450 mm.（4）Compared with zonal climax vegetation,the restoration degree of ecological multifunction of artificial vegetation on the Loess Plateau was less than 60%.Vegetation restoration increased the resilience of regional carbon sink and soil and water conservation,but caused the degradation of soil water storage capacity.The resilience index of the carbon sink and soil and water conservation increased with the restoration years,while the resilience index of the water storage decreased.However,the resilience of water storage function of grassland was more sustainable compared with that of trees and shrubs.compared with forest and shrub,the resilience of water storage function of grassland was more sustainable.In addition,the resilience of ecological functions was the highest in the area with the mean annual precipitation>550 mm.（5）Vegetation restoration on the Loess Plateau has significantly improved cultural ecosystem services such as aesthetics,physical and mental health,social relations and a sense of place.Regarding the different types of cultural ecosystem services,the public most strongly perceived esthetic services,but had the lowest perception of cultural heritage and religious beliefs after ecological restoration.Gender,age,education,occupation and income were the main factors affecting cultural ecosystem services,and gender and age were the most critical factors affecting public perceptions.Men were more likely to perceive cultural ecosystem services than women,while older interviewees had higher perceptions of the value of physical and mental health services,education and science.In addition,regional landscape characteristics were also important factors affecting public perceptions,forestlands were perceived as playing more important roles than other landscape types in providing cultural ecosystem services. |
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