Effects of climate,land use and land cover changes on soil loss in the Three Gorges Reservoir area,China

Climate,land use and land cover(LULC)changes are among the primary driving forces of soil loss.Decoupling their effects can help in understanding the magnitude and trend of soil loss in response to human activities and ecosystem management.Here,the RUSLE model was applied to estimate the spatial-temporal variations of soil loss rate in the Three Gorges Reservoir(TGR)area during 2001-2015,followed by a scenario design to decouple the effects of climate and LULC changes.The results showed that increasing rainfall generated as much as 2.90×10^(7)t soil loss in the TGR area.However,such effect was offset by changes in LULC particularly afforestation,which retained about 1.10×10^(7)t soil annually.Other human activities such as dam development and urbanization aggravated soil loss by as much as 1.40×10^(6)t annually.Because of land use policies that favor economic development,distinct spatial variances of soil loss were observed in TGR area.Soil loss in some counties located downstream of the TGR area(i.e.,close to the dam)was more influenced by dam development,but soil loss in the other counties was more influenced by urbanization.As climate change(i.e.,increasing rainfall)did not affect plant performance in TGR area,our findings suggested that ecological restoration was more beneficial to curb the amount of soil loss caused by urbanization and dam construction.

Pursuing the goal of carbon neutrality in China:path for realization of carbon sequestration in planted forests

Tree plantations are an important forest resource that substantively contributes to climate change mitigation and carbon sequestration.As the area and standing volume of tree plantations in China have increased,issues such as unreasonable structure,low productivity,limited ecological functionality and diminishing ecological stability have occurred,which hinder the ability of tree plantations to enhance carbon sequestration.This study outlined the trajectory of carbon sequestration and its associated benefits in tree plantations by examining the current state of tree plantation establishment and growth,elucidated the strategies for advantages of carbon sequestration and climate change mitigation in planted forests,and summarized the existing problems with tree plantations.This paper underscores the pressing need for concerted efforts to boost carbon sequestration within planted forests and proposes management and development strategies for Chinese tree plantations.In the future,it will be necessary to apply scientific theories to practice and develop multi-objective management optimization models for the high-quality development of tree plantations.This will involve establishing a cohesive national carbon trading market,improving the prediction of carbon sequestration,and identifying priority zones for afforestation and reforestation,to better serve China’s national strategy for achieving peak carbon and carbon neutrality.