草地灌丛化成因及其对生态系统的影响研究进展

The Advance of Shrub Encroachment in Grassland and Its Impact on Ecosystem

由于气候变化和人类活动的影响,草地生态系统正经历着剧烈变化,全球草地广泛发生了原生灌木或乔木的密度、盖度和生物量增加的现象。从草地灌丛化的特征及分布、形成机制和对草地生态系统的影响等三方面进行了阐述。放牧、气候变化等诸多因素驱动了草地灌丛化的发生,草地灌丛化过程不但改变了草地生态系统的生物多样性和外貌,而且改变了其结构和功能。灌丛营造了小气候环境,改变了种间关系,调节了土壤营养和物质循环。未来应结合遥感技术对灌丛化发生的面积进行估算,确定灌丛化驱动因素,并准确评价灌丛化草地的结构、功能和服务。

Global change and the intensification of human activities have led to drastic change in grassland ecosystems and the density, coverage and biomass increase of native shrubs or woody have taken place in the grassland around the world.This paper elaborated encroachment from three aspects, including characteristics, distribution, formation mechanism, and effects of encroachment on grassland ecosystem.Many factors, such as grazing, global change etc., have driven encroachment.Grassland encroachment process not only has changed biodiversity and physiognomy of grassland ecosystem, but also has altered its structure and function.Encroachment plants created microclimate condition, changed interspecies relation, and regulated soil nutrients and material cycle.In the further, remote sensing technology should be combined to estimate the area of encroachment, determine the driving factor of encroachment, and accurately evaluate the structure, function and service of shrub-encroached grasslands.