古尔班通古特沙漠种子秋萌的环境依赖性  

Environment-dependence of seed germination in autumn in Grurbantonggut Desert

作　　者：曾晓玲[1] 刘彤[1] 沈雪莹[1] 牛攀新[2] 

机构地区：[1]石河子大学生命科学学院,新疆石河子832000 [2]石河子大学农学院林学系,新疆石河子832000

出　　处：《生态学杂志》2011年第8期1604-1611,共8页Chinese Journal of Ecology

基　　金：国家"十一"五科技支撑计划重大项目(2007BAC17B03)资助

摘　　要：种子的萌发时间分散在不同季节,有利于资源的利用,种群的延续与扩增。通过野外对秋萌物种种类与分布特征进行调查,结合种子生物学特征和萌发对温度、水分的响应,探究古尔班通古特沙漠秋萌物种种子的共性特征及萌发的环境依赖性。结果表明:67个样地中有33个样地有秋萌物种分布,物种以1年生短命植物为主。秋萌物种的果实易开裂,种子寿命较短,且不休眠。萌发的高温阈值宽泛,萌发类型不是早春低温类型,与9—11月秋季温度对应;萌发对土壤水分响应敏感,冗余分析发现水分是种子选择萌发时间的限制因子,影响秋萌物种的分布。在气候变化背景下,秋冬降水增多,冬季冻期缩短,推断古尔班通古特沙漠秋萌物种的种类和数量都会呈增加趋势。Seed germination time scatters in different seasons,being propitious to the resources utilization and the population continuation and growth.In this paper,a field survey was conducted on the autumn-germinating plant species and their distribution in Grurbantonggut Desert,and,based on the biological characteristics of their seeds and the responses of the seeds germination to air temperature and soil moisture,the common characteristics of the seeds and the environment-dependence of their germination were studied.Among the 67 sites surveyed,33 sites had autumn-germinating species,and most of them were ephemeral plants.The fruits of autumngerminating plants were easy to dehiscence,and the seeds had a shorter life span without dormancy.The seed germination had a broader high temperature threshold,and the germination type was not a low-temperature type of early spring but in correspondence to the temperature in autumn（September-November）.The germination was sensitive to soil moisture.Redundancy analysis further revealed that soil moisture was a limiting factor to the germination time of the seeds,and affected the distribution of autumn-germinating plants.Because of the increasing precipitation in autumn and winter and the shortening frozen period in winter under the background of climate change,it was deduced that that the species and number of autumn-germinating plants in Gurbantunggut Desert would be increased.

关 键 词：土壤水分 温度 萌发时间 短命植物 冗余分析 

分 类 号：Q948.112[生物学—植物学]