西双版纳尚勇热带季节雨林物种组成及其与环境因子关系

Species Composition and Its Relationship with Environmental Factors in Seasonal Tropical Rainforest in Shangyong of Xishuangbanna

西双版纳热带雨林群落结构复杂,物种组成丰富,是生物多样性维持机制研究的天然试验平台。基于西双版纳国家级自然保护区尚勇片区1 hm 2热带季节雨林动态监测样地,分析了该群落的物种组成、物种丰富度及重要值特征,揭示影响群落物种组成的环境因子差异。结果表明,热带季节雨林样地中发现胸径≥1 cm的木本植物共计2677株,属于65科225种;乔木、灌木和藤本植物分别有150、16、59种,物种数量随样方数量累计呈较快增长趋势。千果榄仁、思茅崖豆和木奶果是样地内重要值排前3位的物种,累计重要值为22.17%,优势种分布不明显。木本植物丰富度与土壤pH、速效磷含量间呈显著或极显著的负相关;热带季节雨林的物种分布与土壤pH、速效磷含量、全氮含量及毛管持水量等4个环境因子间存在密切关系,其中,土壤pH、速效磷含量和毛管持水量对物种分布具有积极影响,而土壤全氮含量对物种分布具有消极影响。

The tropical rainforest community in Xishuangbanna has a complex structure and rich species composition,which is the natural study platform for biodiversity maintenance mechanism.Based on a dynamic monitoring sample plot of 1 hm 2 seasonal tropical rainforest in Shangyong area of Xishuangbanna National Nature Reserve,the species composition,species richness,and important value characteristics of the community were analyzed,revealing differences in environmental factors affecting the species composition of the community.The results showed that there were a total of 2677 woody plants with a diameter at breast height≥1 cm,belonging to 225 species and 65 families;there were 150 species of arbors,16 species of shrubs and 59 species of vines,and the number of species increased rapidly with the cumulative number of plots.Terminalia myriocarpa,Millettia leptobotrya and Baccaurea ramiflora were most dominant species in the plot with 22.17% of cumulative importance value,which suggested that no significant dominant species were found in this community.The species richness of woody plant had significant or extremely significant negative correlation with soil pH and available phosphorus.The species distribution of seasonal tropical rainforest had close relationship with four environmental factors,including soil pH,available phosphorus content,total nitrogen content,and capillary water capacity.Soil pH,available phosphorus content and capillary water capacity had a positive impact,while soil total nitrogen had a negative impact on species distribution.