羽毛针禾（Stipagrostis pennata）克隆构型及不同环境中的分株种群特征

以古尔班通古特沙漠不同环境（沙丘不同坡位、不同伴生植物、不同流动性沙丘）中的羽毛针禾（Stipagrostis pennata）种群为研究对象，通过测定羽毛针禾分株平均高度、节间长、分蘖株数、根茎直径、地下根状茎数、平均地下根状茎长等指标，分析羽毛针禾的克隆构型及不同环境中的分株种群特征。结果表明：羽毛针禾分株强度大，分枝多，分株间的间隔物（节间长）高度缩短，表现出典型的“密集型”克隆生长构型。同时，比较半固定沙丘不同坡位羽毛针禾的分株种群特征，坡顶上的羽毛针禾在分蘖株数和平均根状茎长均显著高于坡底；分析羽毛针禾与不同伴生植物的分株种群特征表明，羽毛针禾与鹤虱的伴生群落中，其分蘖枝数显著高于羽毛针禾与白茎绢蒿的伴生群落，且有较高的分枝密度和较短的平均根状茎长；与半固定沙丘相比，生长于固定沙丘的羽毛针禾分株种群具有显著的分蘖株数、根状茎数，以及较长的根茎直径、较大的地上部分生物量和地下根状茎生物量。最后，结合克隆植物对资源的利用对策及表型的可塑性，对不同环境中的羽毛针禾分株种群特征进行了讨论。

Clonal Configuration and Ramet Population Characteristics of Stipagrostis pennata in Different Habitats

This paper researched the morphological plasticity of clonal plant ramets at individual and population level, clonal configuration and ramet population characteristics of Stipagrostis pennata in different habitats (different slope positions, associated with different plant communities, different mobile dunes) in the Gurbantunggut Desert, Junggar Basin, Xinjiang. The average height of ramets, internode length, number of tillers, root diameter, underground rhizomes, average length of underground rhizomes of S. pennata were measured and analyzed, and the parameters of clonal configuration and the ramet  population characteristics of S. pennata in different habitats were studied. The results showed that the strength of ramets of S. pennata was high, the branches were more, and the spacer among ramets (internode length) was highly reduced, so S. pennata was in a typical “intensive” clonal growth pattern. Moreover, after compared the ramet population characteristics of S. pennata at different slope positions of semi-fixed sand dunes, it was revealed that the number of tillers and the average rhizome length of S. pennata at the dune top were significantly higher than those at the dune bottom. After analyzing the ramet population characteristics of S. pennata associated with different plant communities, it was revealed that the branches of S. pennata associated with Lappula myosotis community were obviously more than those associated with Seriphidium terraealbae, the branching density was higher, and the average rhizome length was shorter. Compared with semi-fixed dune, S. pennata growing at fixed dune had significantly the larger numbers of tillers and rhizomes, longer root diameter and higher aboveground biomass and underground rhizome biomass. The ramet population characteristics of S. pennata in different habitats were discussed based on the integration of clonal plants at the aspects of resources utilization and phenotypic plasticity.