Abstract: Annual plant species are the main component of the vegetation in arid and semi-arid desert regions, with their unique traits as the good candidates for the study of many key bio-ecological issues. In this paper, their seed germination strategy, seedling adaptation mechanism to environment, seed dispersal, and soil seed bank were summarized, and the biotic and abiotic factors affecting the composition and dynamics of annual plant species populations and communities were discussed. Because of their important ecological functions in desert floral systems, the study of annual plant species would benefit to the conservation and restoration of desert ecosystem, rational utilization of resources, and sustainable development of desert regions.

Key words: Nutrient use efficiency, Resorption, Nutrient availability, Internal cycling, Nutrient loss