沙丘移动导致的荒漠植被衰亡与恢复演替

Desert vegetation in arid sand zone plays important roles in mitigating sand encroachment, and maintaining material cycle and energy exchange of desert ecosystem. The migration of dune could bury the desert vegetation, leading to their degeneration and death. Meanwhile, as the migration of sand dunes, the desert vegetation could occur restoration and succession quickly. However, previous studies paid limited attention to the process of desert vegetation being buried by sand dunes and their natural restoration and succession. In this project, we will select the southern passages of the Badain Jaran Desert as our study area to research dune migration induced degeneration and succession of desert vegetation through integrating processes of aeolian landform and desert ecology. The migration speed and morphology parameters of sand dunes will measured by RS image interpretation and filed measurement, and the buried time of sand dunes to desert plant will be estimated. The rate of vegetation survival and dead branches of desert vegetation after different buried time will be measured through RS image interpretation and field survey, and the threshold buried time of death and degeneration of different kind desert vegetation will be determined, then the ability of different desert vegetation to resist the burying of sand dunes will be analyzed. The process and mechanism of desert vegetation succession will be revealed by RS image interpretation, field survey and investigation, and laboratory experimental analysis. The project will be helpful to understand the resistance to sand dune burying, adaptation to aeolian sand environment and succession mechanism of desert vegetation, and has importance in protection of desert vegetation diversity.

干旱流沙区的荒漠植被具有减缓流沙侵害及维持荒漠生态系统物质循环和能量交换的重要作用。沙丘移动会导致荒漠植被衰亡；同时，伴随沙丘移动，荒漠植被群落会发生快速的恢复演替。已有研究对干旱区流动沙丘对荒漠植被的埋压过程及荒漠植被恢复演替过程关注较少。本项目拟选择巴丹吉林沙漠南缘输沙带作为研究区，将风沙地貌过程和荒漠生态过程相结合，开展沙丘移动导致的植被衰亡与恢复演替研究。通过遥感影像和实地测量沙丘形态参数和移动速度，估算沙丘对荒漠植被的埋压时间；通过遥感测量和野外调查，测定沙丘埋压后荒漠植被的存活率和干枝率，确定不同种类荒漠植被衰亡的临界埋压条件，探讨不同种类荒漠植物抵抗沙丘埋压能力；通过遥感测量、野外调查和观测及室内实验分析，确定荒漠植被的演替序列，揭示流沙区荒漠植被恢复演替的机制，为荒漠植被抗沙埋能力、对风沙环境适应能力及恢复演替机制的认识和理解提供依据，为荒漠植物多样性保护提供理论指导。

干旱流沙区的荒漠植被具有减缓流沙侵害及维持荒漠生态系统物质循环和能量交换的重要作用。沙丘移动会导致荒漠植被衰亡；同时，伴随沙丘移动，荒漠植被群落会发生快速的恢复演替。本项目以巴丹吉林沙漠东南缘输沙带作为研究区，通过野外调查、遥感测量及室内实验分析等方法，测量了沙丘的形态参数和移动速度，估算了沙丘对荒漠植被的埋压时间，确定了荒漠植被衰亡的临界埋压条件，探讨了荒漠植被的格局及其与风沙过程的互馈效应，研究了荒漠植被的恢复演替序列和机制，为荒漠植被对风沙环境适应能力的认识和荒漠植物多样性的保护提供理论指导。