干旱区生态环境知识资源中心

Aiming to study the evolutionary trend of the annual autumn germination in Gurbantunggut Desert with more rains, the model of autumn germination ratio was established on the basis of the investigation by Valleriani and others. Altogether the paper presents four findings: (1) As for the different species, the bigger the ratio of plant yield between autumn germination and spring germination is, the lower the germination rate of evolutionary stability is; (2) The germination rate of evolutionary stability would increase given that the climate was pleasant for autumn germination. (3) The lower the dormancy survival rate of the species is, the higher the germination rate of evolutionary stability is; (4) As for the same species, the smaller the ratio of prospective yield between autumn germination and spring germination is, the lower the germination rate of evolutionary stability is; on the contrary, the germination rate of evolutionary stability would increase. After analyzing the tendency of the germination rate of evolutionary stability taking into account of the climate change, it turned out in the model that the less rains in spring, the lower the germination rate of evolutionary stability is and that more rains in autumn, less in spring as well as way too cold weather in winter all contribute to the seeds' autumn germination. In conclusion, combined with the model and the fruit types of autumn germination it is speculated that the annual with large quantity of plants, seeds plus lower dormancy survival rate would be easier to germinate on condition of climate change. Therefore, this paper supplies reference to the features as well as evolutionary trend of plants in arid desert in terms of global climate change. (C) 2011 Published by Elsevier B.V. Selection and/or peer-review under responsibility of School of Environment, Beijing Normal University.