云南省西双版纳勐腊县橡胶林下植物多样性分析

Analysis of undergrowth plant diversity of rubber plantations in Mengla County,Xishuangbanna,Yunnan Province

为探究云南省勐腊县橡胶林下植物物种组成及多样性等基本情况,对勐腊县内94个橡胶林下植物样方(20 m×20 m)和20个土壤样方进行调查,分析环境、空间因素对林下植物物种分布和植物多样性影响情况。结果显示:勐腊县橡胶林下植物共计87科、197属、300种,优势物种为银柴(Aporusa dioica)、阔叶箬竹(Indocalamus latifolius)、葛藤(Pueraria lobata)等;20个土壤样地中,全氮、全磷、全钾等成分均存在中程度变异,其最高含量分别为1.0927%、0.1726%、2.6499%。对植物物种及优势物种分布影响因素分析(RDA)表明:地形对优势物种分布显著影响;土壤全磷和坡度对植物物种分布达到极显著影响(P<0.01)。在植物多样性分析中,坡度对植物多样性影响显著高于其他影响因子(P<0.05),辛普森指数(Simpson,D)和香农指数(Shannon-Wiener,H)在坡度大于35°时最高,并且在回归分析中拟合度较高;海拔大于600 m时,Simpson指数和Shannon-Wiener指数较高,物种丰富度(S)在600~700 m整体高于其他海拔梯度;橡胶树(Hevea brasiliensis)在8~14树龄时,植物物种丰富度最高。勐腊县橡胶林下植物物种较丰富,但受人工干扰影响导致植物多样性较差,如果通过合理的管控会使橡胶林下植物多样性变高,有助于生态恢复。

In order to explore the species composition and diversity of plants in the rubber plantations of Mengla County,Xishuangbanna,Yunnan,China,94 plant quadrates(20×20 m)and 20 soil quadrates were arranged for observation in the understory of the rubber plantations in Mengla County to analyze the effects of environmental and spatial factors on the species distribution and plant diversity in the rubber plantations.The results showed that there were 87 families,197 genera and 300 species of understory plants in the rubber plantations in Mengla County,and that the dominant species were Aporusa dioica,Indocalamus latifolius,Pueraria lobata and so on.The contents of total nitrogen,phosphorus and potassium in the 20 soil quadrates varied moderately,and their highest contents were 1.09%,0.17%and 2.65%,respectively.The analysis of factors influencing the distribution of plant species and dominant species by using the RDA method showed that topography had significant effect on the distribution of dominant species,and that soil total phosphorus and slope had significant effects on plant species distribution(P<0.01).In the analysis of plant diversity,the effect of slope on plant diversity was significantly higher than that of other factors(P<0.05).Simpson(D)index and Shannon-Wiener(H)index were the highest at the slope>35°,and the fit degree was higher in regression analysis.The D and H were higher at the altitudes greater than 600 m,and species richness(S)was higher at the elevations between 600 m and 700 m than at the other elevations.The plant species richness was the highest in the rubber plantations at the age of 8~14 years old.The plant species under the rubber plantations in Mengla County are abundant,but the plant diversity is poor due to artificial disturbance.The plant diversity under the rubber plantations can be increased through reasonable management and control,which is conducive to ecological recovery.