放牧和割草条件下瑞香狼毒种群生物学特性比较

A Comparative Study on Biological Traits of Stellera chamaejasme Population Under Grazing and Mowing Conditions

研究了科尔沁草地放牧和割草两种利用方式下瑞香狼毒植株的生物学特性异同。结果表明:两种生境中的瑞香狼毒在某些特性上存在很大的差异,叶片厚度、叶片体积和叶片自然含水量均以割草地大于放牧地,但叶片饱和含水量放牧地却比割草地大。两种生境中瑞香狼毒的其他特性没有显著差异,这可能与牲畜对有毒植物不采食有关。运用Pearson相关系数分析两种生境中两两特性间的相关关系可知:两种生境中的构件特性间大多数为不相关,而且两生境的正负相关的成对特性也不尽相同。其中,茎干重与地上干生物量之间均表现出最强的正相关性,它们的Pearson相关系数分别为0.981(放牧地)和0.990(割草地),而叶片自然含水量与叶片干物质含量则表现最强的负相关性,其Pearson相关系数均为-0.998。线性回归分析表明:两组相关特性之间的R2值均大于90%,这说明它们之间的相关性极强。

21 modular traits of Stellera chamaejasme in two different habitats were studied. Results indicated that there were significant differences between some modular traits. The leaf thickness, leaf volume and the natural water content of Stellera chamaejasme in mowing land were more than in grazing land, but the leaf saturated water con- tent in grazing land was more than in mowing land. There was no significant difference between other modular traits, which was probably due to the poisonous plants not being eated. Using Pearson correlation coefficients to analysis the relationship of modular traits pairs in two different habitats, most of traits pairs were not correlated; the most positive correlation occurred between shoot dry biomass and above -ground dry biomass, with r values of 0. 981 （ grazing land） and 0. 990 （ mowing land）. However, the most negative correlation between leaf natural water content and leaf dry matter content, with r values of - 0. 998. The regression analysis had R^2 values 〉 90%, which indicated the relationships were significant.