荒漠一年生植物小画眉草的种群动态调节与模拟  

Population regulation and dynamical simulation of annual plant Eragrostis poaeoides in desert region

作　　者：徐彩琳[1] 李自珍[1] 

机构地区：[1]兰州大学干旱农业生态国家重点实验室,兰州730000

出　　处：《西北植物学报》2002年第6期1415-1420,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金资助项目 ( 39970 135

摘　　要：以分布在沙坡头沙漠试验研究站人工固沙植被中的一年生植物小画眉草为例 ,研究了荒漠一年生植物不同时间尺度上的种群动态与调节机制 ,试验结果表明 :1一年生植物小画眉草种群的续存与其种子库中种子的分批萌发对策密切相关 ;2同一个生长季内 ,制约小画眉草种群数量变动的关键因子随降水条件的不同而变化 ,即当环境适宜度较小时 (干旱胁迫 ) ,非生物因子 (降水 )限制种群数量 ;当环境适宜度较大时 ,密度依赖的竞争作用调节种群大小 ;3在较长的生态时间尺度上土壤特性 (结皮厚度、养分含量 )也是影响小画眉草种群动态的一个重要因素 ;4小画眉草种群的存活曲线属于 C型 ,说明该种是较为典型的 r-对策者。Taking the annual plant Eragrostis poaeoides ,which distributes in the planted vegetation for fixing sand dunes of Shapotou Desert Experimental Research Station,as an example,the population dynamics and its regulative mechanisms of desert plant in different time scales were studied.The conclusions are as the following:① Persistence of the annual plant Eragrostis poaeoides is closely related to the germination behavior of seeds in seed bank.② In a growth season,the key factor restricting population size of Eragrostis poaeoides changes with rainfall.When the environmental fitness (water stress) is small,precipitation restricts the population size,but density dependent competition regulates the population size if the environmental fitness is large.③ In long term ecological time scale the soil characteristics,such as the thickness of soil crust and nutrient content,play a key role in affecting the population dynamics of Eragrostis poaeoides .④ The C type survival curve of Eragrostis poaeoides means the species is a r stratigist.

关 键 词：一年生植物 小画眉草 种群动态调节 模拟 荒漠生境 时间尺度 生活史 

分 类 号：Q948.154[生物学—植物学] Q948.44