不同生境下假臭草生长特征分析

通过测定庄稼地、弃耕地、桉树林、公路边4种生境下假臭草叶面积(LA)、比叶面积(SLA)、LDMC和株高等形态特征、植株各构件生物量及生物量分配比和假臭草种群盖度、密度等种群数量性状,研究不同生境类型下假臭草个体的形态特征、生物量及生物量分配和种群生长状况的差异。结果表明:光照和土壤养分对假臭草的形态特征、生物量及生物量分配和种群数量性状的影响显著;低光照、高土壤养分生境下假臭草的LA、SLA、株高较高,假臭草叶片的LDMC较小,植株的花序数较少,生物量主要向叶和茎器官进行分配,根和花果器官的生物量分配则受到限制;高光照、养分贫瘠生境下假臭草的LA、SLA、株高较低,假臭草叶片的LDMC较大,生物量主要向根和花果器官进行分配,种群的盖度、密度、生物量和高度等种群数量性状较低,种群生长状况较差;高光照、肥沃养分生境为假臭草的最适生境,假臭草构件的资源配置较为优化,株高、基径粗、冠宽和花序数等形态指标较大,种群盖度、密度、生物量等种群数量性状较大,种群生长较好。

Analysis on the growth characteristics of Eupatorium catarium in different types of habitats

Morphological characteristics such as LA,SLA,LDMC and plant height,biomass and biomass distribution and population quantitative trait of Eupatorium catarium such as population coverage and density,were determinated to study the differences of morphological characteristics,biomass and biomass distribution and population quantitative trait of E. catarium in farmland,wastelands Eucalyptus forest and roadside 4 different kinds of habitats. The results were as followed:Light and soil nutrients had significant influence on the morphological characteristics,biomass and biomass distribution and population quantitative trait of E. catarium,indicating that E. catarium in low-light but high soil nutrient habitats had larger LA,SLA and plant height, but smaller leaf LDMC and fewer plants inflorescence. Biomass of E. catarium was mainly allocated to the leaf and stem organs,but limited to the root and the flower organ. Whereas,LA,SLA and plant height of E. catarium in high-light but low soil nutrient habitats were smaller,but leaf LDMC lager. Biomass of E. catarium was mainly allocated to the root and the flower organs. Population traits such as population coverage,density,biomass and height are smaller,indicating poor population growth. High-light and high soil nutrient habitats was optimum habitat for E. catarium,in which morphological indicators of E. catarium such as plant height,base diameter,crown width and number of inflorescences,as well as the population traits such as population coverage,density and biomass were larger,indicating better population growth.