Coupling Relationship Between Vegetation and Soil in Different Zones of Unstable Slopes in the Jiangjiagou Valley,China
A coupling relationship between vegetation and soil is crucial for evaluating the coordinated and sustainable development of ecosystems.Past research on the synergetic mechanism between vegetation and soil primarily concerned about the ecosystems disturbed by human activities or suffered by natural succession,with kind of awareness of the restoration processes of disaster-disturbed ecosystem merely at a plot of instable slope,other than a complete slope.In this study,five representative unstable slopes with three zones(stable,unstable and accumulation zone)across three climate zones at the Jiangjiagou valley in southeastern China were selected as research objects.Inclusive of seven vegetation indicators and eight soil indicators in the proposed evaluation system,it used the entropy weight method and principal component analysis to determine the comprehensive weight of each indicator as well as the main factors affecting the unstable slope ecosystem.A coupling coordination degree model of vegetation-soil were also constructed.(1)Shannon Wiener diversity index,Simpson dominance index and Margalef richness index were the most significant factors governing the stability of the unstable slope ecosystems in the Jiangjiagou valley.In addition,vegetation biomass,soil available potassium,organic carbon,total nitrogen and hydrolyzed nitrogen also played an important role in regulating ecosystem stability.(2)The comprehensive vegetation and soil evaluation indexes at the stable zones were higher than those obtained at the unstable and accumulation zones on the unstable slopes in the Jiangjiagou valley.The comprehensive vegetation evaluation indexes exhibited the highest values in the temperate humid mountain ridge region,followed by the subtropical and warm temperate sub-humid region,and the lowest values in the dry-hot valley region.It got significantly lower values on the comprehensive soil evaluation indexes in the subtropical and warm temperate sub-humid region than ones in the other two climate zones.(3)Both the unstable and accumulation zones in the subtropical and warm temperate sub-humid region and the dry-hot valley region exhibited primary coordinated development of vegetation and soil,while the stable zones and all zones of the temperate humid mountain ridge region exhibited intermediate coordinated development of vegetation and soil.The temperate humid mountain ridge region showed lagging soil development,while the dry-hot valley region showed lagging vegetation development.The research results can provide theoretical support for formulating optimal strategies to promote rapid and effective restoration and coordinated sustainable development of the fragile ecosystem in the Jiangjiagou valley.
unstable slopevegetationsoilcouplingthe Jiangjiagou valley
NETL
NSTL
万方数据
