Manipulated microtopography alters plant community development in fragile farm-pastoral transition zone

典型农牧交错带中基于微地形营造的生态恢复措施对植物群落构建的影响

The ecosystems within agro-pastoral transition zones exhibit inherent fragility and heightened susceptibility to climate variability,exacerbated by profound degradation resulting from anthropogenic activities.Subsequent vegetation degradation in these areas precipitates severe soil erosion,presenting formidable challenges for ecological restoration efforts.The utilization of microtopographic structures to mitigate soil erosion and facilitate vegetation recovery stands as a prominent strategy for vegetation restoration within agro-pastoral transition zones.Despite the acknowledgment in current restoration practices that the efficacy of microtopography-based restoration is contingent upon slope,aspect and elevation,there remains a notable absence of precise observed information on this correlation.This study,conducted in the Bashang Grassland,a typical agro-pastoral transition zone in northern China,aims to fill the information gap concerning the correspondence between microtopographic structures and restoration outcomes.Our findings revealed that microtopography has a significant impact on vegetation characteristics,with outcomes varying by location.Shaded slopes displayed higher biomass and density compared with sunny slopes and valleys.While microtopography affected community structure,it did not substantially alter species richness,highlighting the critical role of location and pit construction in successful restoration endeavors.This study provides insights for the selection,design and assessment of microtopography-based restoration in vulnerable ecosystems.

农牧交错带的生态系统对气候变化高度敏感,同时人类活动使得这些区域的植被退化加剧了土壤侵蚀,给生态恢复工作带来了巨大的挑战。利用微地形结构,如鱼鳞坑,来减缓土壤侵蚀并促进植被恢复,已成为农牧交错带植被恢复的重要策略。尽管目前的恢复实践中微地形恢复措施的效果取决于坡度、朝向和海拔,但缺乏精确的观测数据来证实这种关联性。本研究以中国北方典型的农牧交错区——坝上草原为研究对象,旨在揭示关于微地形结构与恢复效果之间的关系。研究结果表明,微地形营造措施对植被特征有显著影响,其结果因更大尺度的地貌结构而异。阴坡上微地形结构中的植被生物量和密度高于阳坡和山谷。虽然微地形修复会影响群落特征,但并未显著改变物种丰富度,这表明微地形营造在农牧交错带生态修复实践中的关键作用。本研究得到的相关结果为脆弱生态系统中基于微地形的恢复选择、设计和评估提供了新见解。