Chen Guangsheng, Zeng Dehui, Chen Fusheng, Fan Zhiping, Geng Haiping
Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Ying Yong Sheng Tai Xue Bao. 2003 Dec;14(12):2295-300.
Due to the inclemency of climate and soil conditions and the intense disturbance of human beings, the soil resources heterogeneity in arid and semi-arid grassland ecosystems worldwide was gradually increased during the last century. The interaction between soil heterogeneity and shrubs induced the autogenic development of "fertile islands" and the increasing spread of shrubs in the grassland ecosystems. The development of "fertile islands" around individual shrubs could change the vegetation composition and structure, as well as the distribution patterns of soil resources, and thus, reinforced the changes of the ecosystem function and structure from a relative stable grassland ecosystem to a quasi-stable shrubland ecosystem. The study of "fertile islands" phenomenon would help us to understand the causes, consequences and processes of desertification in arid and semi-arid areas. In this paper, the causes of "fertile islands", its study methods and significance and its relationship with shrub spreading as well as the responses of vegetation to it were summarized. The problems which might occur in the study of this phenomenon were also pointed out. Our aim was to offer some references to the study of land desertification processes and vegetation restoration in the arid and semi-arid regions.
由于气候和土壤条件恶劣以及人类活动的强烈干扰，上个世纪全球干旱和半干旱草原生态系统中的土壤资源异质性逐渐增加。土壤异质性与灌木之间的相互作用导致了“肥岛”的自生发育以及灌木在草原生态系统中的不断扩散。单株灌木周围“肥岛”的发育会改变植被组成和结构以及土壤资源的分布格局，进而强化生态系统功能和结构从相对稳定的草原生态系统向准稳定的灌丛生态系统的转变。对“肥岛”现象的研究有助于我们理解干旱和半干旱地区荒漠化的成因、后果及过程。本文总结了“肥岛”的成因、研究方法及意义、其与灌木扩张的关系以及植被对其的响应。同时也指出了该现象研究中可能出现的问题。我们的目的是为干旱和半干旱地区土地荒漠化过程及植被恢复研究提供一些参考。
