西藏拉萨市入侵植物曼陀罗群落物种多样性研究OA北大核心CSTPCD

Lhasa is at the forefront and is central to the construction of the national ecological security barrier.Datura stramonium has become a serious invasion trend in Lhasa,posing significant bioecological safety risks to urban environments.This study selected the D.stramonium communities in the urban area of Lhasa as the research subject,and used the typical plot survey method to analyze the species composition,community similarity coefficient,importance value,and other quantitative characteristics of the plant communities in the D.stramonium invasion areas in Lhasa,as well as the preliminary impact on the diversity of the invaded plant communities.This provides data for the study of the diversity of invasive plant communities within urban areas using Lhasa as a case study.The results showed that 1)the plant community species composition in the D.stramonium invasion areas in Lhasa totaled 74 species across 62 genera and 22 families,among which the Asteraceae,Poaceae,and Amaranthaceae families had the most species,with as many as 23 species of alien plants.The annual herbaceous plants accounted for 47.30%of the total number of plants.2)There are 4 plant species with a high frequency of occurrence(91%-100%)in the D.stramonium communities,accounting for 5.41%of the total number of species,which is a very small proportion,indicating a clear dominance of certain species;the native plants Dysphania schraderiana and Chenopodium album,along with D.stramonium,have the highest co-occurrence frequency,while Kali monopterum and Taraxacum grypodon also have significant frequencies.Among the invasive plants,the highest co-occurrence frequencies with D.stramonium were found in Galinsoga parviflora and Amaranthus retroflexus,and the Bray-Curtis similarity coefficient of the community quadrats was generally low,indicating significant variation in the species diversity composition of the D.stramonium communities and a wide ecological niche breadth.3)The Pearson correlation analysis results indicated that the species richness of the quadrats was negatively correlated with the importance value of D.stramonium,meaning that as the coverage of D.stramonium increased,the species richness significantly decreased.D.stramonium plant communities in Lhasa contain a considerable number of invasive companion species.Future efforts should focus on conducting a comprehensive baseline survey of alien invasive plants throughout the urban area of Lhasa,and on strengthening basic research related to the invasion mechanisms of D.stramonium in high-altitude areas.The results of this study provide plant ecology data for the invasion and prevention of D.stramonium in built-up areas of Lhasa.