不同空间分布方式对刺穗藜生长格局的影响  

Effects of different spatial distributions on growth pattern of Chenopodium aristatum

作　　者：刘振国[1] 李镇清[2] 

机构地区：[1]上海大学生命科学学院,上海200444 [2]中国科学院植物研究所植被与环境变化国家重点实验室,北京100093

出　　处：《草业科学》2008年第12期56-61,共6页Pratacultural Science

基　　金：国家重点基础研究发展计划项目(2007CB108904)

摘　　要：在内蒙古退化草原上一年生植物刺穗藜Chenopodium aristatum呈聚集分布。经过长期进化而形成的聚集分布是否在其个体的生长格局上表现出显著的优势?为探讨此问题,用盆栽控制试验的方法研究了不同空间分布方式(均匀、聚集和随机分布)下刺穗藜种群的生长格局。结果表明,不同空间分布方式对刺穗藜个体的高度(P=0.026)、地上生物量(P=0.004)、地下生物量(P=0.049)以及总生物量(P=0.004)均具有显著影响。刺穗藜个体的高度在均匀分布下最大,并且显著大于聚集分布(P=0.014)和随机分布(P=0.023)下的高度,后两者间无显著差异。相反,在聚集分布和随机分布下各生物量指标都显著大于均匀分布下的指标,而聚集分布和随机分布下比较各指标无显著差异。由此看来,在刺穗藜个体高度上,聚集分布并没有表现出比均匀分布和随机分布显著的优势,但在各生物量指标上,聚集分布表现出比均匀分布显著的优势,而和随机分布相比没有表现出显著优势。因此,刺穗藜的这种自然聚集分布的进化优势只是体现在其个体生长格局的某些指标上,此结果可能是控制试验条件下,人为排除了自然条件下种间相互作用(种间竞争)和各种外界干扰(如动物的直接取食、动物的来回践踏活动等)的原因造成的。On degraded Inner Mongolia grassland, Chenopodium aristaturn was companion species and normally aggregated. In order to explore whether natural spatial distribution type formed after long term evolution affect the existence of C. aristaturn, this paper studied the growth pattern of C. aristaturn population under regular, aggregate and random spatial distributions. Results showed that the spatial distribution type significantly affected height of individuals, aboveground biomass, below- ground biomass and total biomass of C. aristaturn population. Height of individuals was the tallest under regular distribution and significant taller than those under both aggregate and random distributions. At the same time, there was no significant difference under aggregate and random distributions. However, biomass indices （aboveground biomass, belowground biomass and total biomass） under aggregate and random distribution were significantly larger than those under regular distribution, but there was no si tribution. The individual gnificant difference between biomass indices under aggregate and random dis height of C. aristatum aggregate distribution did not show a significant advantage over regular and random distributions, while the three biomass indices of aggregate distribution showed significant advantage over regular distribution but not random distribution. The advantage of aggregate distribution formed after long term evolution was put up only on some indices of growth pattern. The reason was that interspecific interactions and exotic disturbances were excluded artificially under the controlled experiment.

关 键 词：刺穗藜 空间分布 竞争 种子分散 适应策略 

分 类 号：S812[农业科学—草业科学]