Soil physicochemical properties and vegetation structure along an elevation gradient and implications for the response of alpine plant development to climate change on the northern slopes of the Qilian Mountains  

作　　者：YANG Yong-sheng ZHANG Li LI Hong-qin HE Hui-dan WEI Ya-xi LUO Jin ZHANG Guang-ru HUANG Yu-ru LI Ying-nian ZHOU Hua-kun 

机构地区：[1]The Key Laboratory of Restoration Ecology in Cold Region of Qinghai Province, Northwest Institute of Plateau Biology,Chinese Academy of Sciences, Xining 810008, China [2]Xining Institute of Surveying and Mapping, Xining 810000, China [3]Keg Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China [4]University of Chinese Academy of Sciences, Beijing 100049, China

出　　处：《Journal of Mountain Science》2018年第5期1006-1019,共14页山地科学学报（英文）

基　　金：funded by National Key R&D Program of China(2017YFA0604801,2016YFC0501802);Natural Science Foundation of Qinghai Province(Grant No.2016-ZJ-910);CAS“Light of West China”Program(2016):Study on the soil moisture with the restoration process of degraded alpine meadows in the Three-River Headwater Region,China;Qinghai innovation platform construction project(2017-ZJ-Y20)supported this work

摘　　要：Elevation is one of key factors to affect changes in the environment, particularly changes in conditions of light, water and heat. Studying the soil physicochemical properties and vegetation structure along an elevation gradient is important for understanding the responses of alpine plants andtheir growing environment to climate change. In this study, we studied plant coverage, plant height, species richness, soil water-holding capacity, soil organic carbon(SOC) and total nitrogen(N) on the northern slopes of the Qilian Mountains at elevations from2124 to 3665 m. The following conclusions were drawn:(1) With the increase of elevation, plant coverage and species richness first increased and then decreased, with the maximum values being at 3177 m.Plant height was significantly and negatively correlated with elevation(r=–0.97, P<0.01), and the ratio of decrease with elevation was 0.82 cm·100 m-1.(2) Both soil water-holding capacity and soil porosity increased on the northern slopes of the Qilian Mountains with the increase of elevation. The soil saturated water content at the 0-40 cm depth first increased and then stabilized with a further increase of elevation, and the average ratio of increase was2.44 mm·100 m-1. With the increase of elevation, the average bulk density at the 0-40 cm depth first decreased and then stabilized at 0.89 g/cm3.(3) With the increase of elevation, the average SOC content at the 0-40 cm depths first increased and then decreased,and the average total N content at the 0-40 cm depth first increased and then stabilized. The correlation between average SOC content and average total N content reached significant level. According to the results of this study, the distribution of plants showed a mono-peak curve with increasing elevation on the northern slopes of the Qilian Mountains. The limiting factor for plant growth at the high elevation areas was not soil physicochemical properties, and therefore,global warming will likely facilitate the development of plant at high elevation areas in thElevation is one of key factors to affect changes in the environment, particularly changes in conditions of light, water and heat. Studying the soil physicochemical properties and vegetation structure along an elevation gradient is important for understanding the responses of alpine plants andtheir growing environment to climate change. In this study, we studied plant coverage, plant height, species richness, soil water-holding capacity, soil organic carbon(SOC) and total nitrogen(N) on the northern slopes of the Qilian Mountains at elevations from2124 to 3665 m. The following conclusions were drawn:(1) With the increase of elevation, plant coverage and species richness first increased and then decreased, with the maximum values being at 3177 m.Plant height was significantly and negatively correlated with elevation(r=–0.97, P<0.01), and the ratio of decrease with elevation was 0.82 cm·100 m-1.(2) Both soil water-holding capacity and soil porosity increased on the northern slopes of the Qilian Mountains with the increase of elevation. The soil saturated water content at the 0-40 cm depth first increased and then stabilized with a further increase of elevation, and the average ratio of increase was2.44 mm·100 m-1. With the increase of elevation, the average bulk density at the 0-40 cm depth first decreased and then stabilized at 0.89 g/cm3.(3) With the increase of elevation, the average SOC content at the 0-40 cm depths first increased and then decreased,and the average total N content at the 0-40 cm depth first increased and then stabilized. The correlation between average SOC content and average total N content reached significant level. According to the results of this study, the distribution of plants showed a mono-peak curve with increasing elevation on the northern slopes of the Qilian Mountains. The limiting factor for plant growth at the high elevation areas was not soil physicochemical properties, and therefore,global warming will likely facilitate the development of plant at high elevation areas in th

关 键 词：QILIAN Mountains ELEVATION Vegetationstructure Soil PHYSICOCHEMICAL properties CLIMATECHANGE 

分 类 号：P461.4[天文地球—大气科学及气象学]