探讨三江源区高寒草地生态系统土壤侵蚀问题在保障青藏高原乃至全球生态和生产功能方面具有重要意义。以^(137)Cs示踪法为基础,结合RUSLE(Revised Universal Soil Loss Equation)模型,以GIS反演为手段,综合分析三江源区2001-2012年土壤...探讨三江源区高寒草地生态系统土壤侵蚀问题在保障青藏高原乃至全球生态和生产功能方面具有重要意义。以^(137)Cs示踪法为基础,结合RUSLE(Revised Universal Soil Loss Equation)模型,以GIS反演为手段,综合分析三江源区2001-2012年土壤侵蚀影响因子的特征和土壤侵蚀空间分布规律。结果表明,1)土壤侵蚀影响因子呈现空间异质性特征,降雨侵蚀力因子年际浮动变化较大,但总体呈上升态势;土壤可蚀性因子呈斑块化分布特征,较高可蚀性类占到总面积的95.66%;坡度坡长因子的空间分布规律受海拔显著影响;植被覆盖与管理因子在研究区自西北向东南呈现空间异质性特点,过度放牧是引起下垫面侵蚀现象严重的主要原因。2)对RUSLE模型的验证显示相关系数和平均均方根偏差分别为0.49和75.29%,RUSLE模型估算存在一定的高估,在没有形成三江源区高寒草地土壤侵蚀机理模型前,应用RUSLE模型仍然是较好的现实选择之一。3)利用RUSLE模型估算的三江源2001-2012年平均侵蚀量为3.1×109 t/年,侵蚀强度分级重心转移分析表明中度侵蚀、强度和极强度侵蚀重心相对集中,侵蚀程度最高的3个地区为格尔木市唐古拉乡、治多县和兴海县。4)由土壤流失量结合市场价值法,估算出研究区2001-2012年平均有机质经济损失价值为114354元/km2,总年均经济损失达399亿元,整个研究区受土壤侵蚀现象所产生的经济损失数额巨大。因此,创新发展三江源区高寒草地"分类、分级、分段、分区"的土壤侵蚀防治措施已迫在眉睫。展开更多
Background: Climate change may strongly influence soil erosion risk, namely through variations in the precipitation pattern. Forests may contribute to mitigate the impacts of climate change on soil erosion and forest ...Background: Climate change may strongly influence soil erosion risk, namely through variations in the precipitation pattern. Forests may contribute to mitigate the impacts of climate change on soil erosion and forest managers are thus challenged by the need to define strategies that may protect the soil while addressing the demand for other ecosystem services. Our emphasis is on the development of an approach to assess the impact of silvicultural practices and forest management models on soil erosion risks under climate change. Specifically, we consider the annual variation of the cover-management factor(C) in the Revised Universal Soil Loss Equation over a range of alternative forest management models to estimate the corresponding annual soil losses, under both current and changing climate conditions. We report and discuss results of an application of this approach to a forest area in Northwestern Portugal where erosion control is the most relevant water-related ecosystem service.Results: Local climate change scenarios will contribute to water erosion processes, mostly by rainfall erosivity increase.Different forest management models provide varying levels of soil protection by trees, resulting in distinct soil loss potential.Conclusions: Results confirm the suitability of the proposed approach to address soil erosion concerns in forest management planning. This approach may help foresters assess management models and the corresponding silvicultural practices according to the water-related services they provide.展开更多
We propose an eco-service provision unit method for estimating the benefit and spatial differences of forests in controlling soil erosion.A total of 197 eco-service provision units were grouped on 1424.43 km2 of fores...We propose an eco-service provision unit method for estimating the benefit and spatial differences of forests in controlling soil erosion.A total of 197 eco-service provision units were grouped on 1424.43 km2 of forest according to differences in vegetation,slope,soil,and rainfall.The amount of soil conservation and its economic value were estimated.The forests in Anji County prevent4.08 9 105 tons of soil from eroding annually,thereby avoiding 1.36 9 104 tons of nutrient loss（on-site cost） and preventing 149 tons of nutritive elements from entering water systems（off-site cost）.From an economic perspective,the soil nutrient conservation in the forests of Anji County generated an annual benefit of 43.37 million RMB（Chinese Currency,6.20 RMB = US$1）.On average,each hectare of ecological forest contributed up to 436 RMB annually because of soil conservation.Ecological complexes with higher rainfall intensity,such as broadleaf forest and red soil on slope gradients [25°,contributed the highest soil conservation benefits.This study identified and quantified the dominant contributors and magnitudes of soil conservation provided by forests.This information can benefit decision making regarding differentiated ecological compensation policies.展开更多
基金ALTERFOR project,“Alternative models and robust decision-making for future forest management”,H2020-ISIB-2015-2/grant agreement No. 676754,funded by European Union Seventh Framework ProgrammeSUFORUN project,‘Models and decision SUpport tools for integrated FOrest policy development under global change and associated Risk and UNcertainty’ funded by the European Union’s H2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement number 691149+2 种基金BIOECOSYS project,“Forest ecosystem management decision-making methods an integrated bioeconomic approach to sustainability”(LISBOA-01-0145-FEDER-030391,PTDC/ASP-SIL/30391/2017)MedFOR,Master Programme on Mediterranean Forestry and Natural Resources Management (Erasmus+Erasmus Mundus Joint Master Degrees,Project 20171917)Centro de Estudos Florestais,research unit funded by Fundacao para a Ciência e a Tecnologia I.P.(FCT),Portugal within UIDB/00239/2020。
文摘Background: Climate change may strongly influence soil erosion risk, namely through variations in the precipitation pattern. Forests may contribute to mitigate the impacts of climate change on soil erosion and forest managers are thus challenged by the need to define strategies that may protect the soil while addressing the demand for other ecosystem services. Our emphasis is on the development of an approach to assess the impact of silvicultural practices and forest management models on soil erosion risks under climate change. Specifically, we consider the annual variation of the cover-management factor(C) in the Revised Universal Soil Loss Equation over a range of alternative forest management models to estimate the corresponding annual soil losses, under both current and changing climate conditions. We report and discuss results of an application of this approach to a forest area in Northwestern Portugal where erosion control is the most relevant water-related ecosystem service.Results: Local climate change scenarios will contribute to water erosion processes, mostly by rainfall erosivity increase.Different forest management models provide varying levels of soil protection by trees, resulting in distinct soil loss potential.Conclusions: Results confirm the suitability of the proposed approach to address soil erosion concerns in forest management planning. This approach may help foresters assess management models and the corresponding silvicultural practices according to the water-related services they provide.
基金supported by the National Natural Science Foundation (No.31200531)National Science and Technology Support Program (No.2012BAC01B08)the National Environmental Protection Public Welfare Industry Targeted Research (No.201209027)
文摘We propose an eco-service provision unit method for estimating the benefit and spatial differences of forests in controlling soil erosion.A total of 197 eco-service provision units were grouped on 1424.43 km2 of forest according to differences in vegetation,slope,soil,and rainfall.The amount of soil conservation and its economic value were estimated.The forests in Anji County prevent4.08 9 105 tons of soil from eroding annually,thereby avoiding 1.36 9 104 tons of nutrient loss（on-site cost） and preventing 149 tons of nutritive elements from entering water systems（off-site cost）.From an economic perspective,the soil nutrient conservation in the forests of Anji County generated an annual benefit of 43.37 million RMB（Chinese Currency,6.20 RMB = US$1）.On average,each hectare of ecological forest contributed up to 436 RMB annually because of soil conservation.Ecological complexes with higher rainfall intensity,such as broadleaf forest and red soil on slope gradients [25°,contributed the highest soil conservation benefits.This study identified and quantified the dominant contributors and magnitudes of soil conservation provided by forests.This information can benefit decision making regarding differentiated ecological compensation policies.
