title: Curvilinear effects of invasive plants on plant diversity: plant community invaded by Sphagneticola trilobata.
abstract: The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants.
authors.affiliation: Institute of Environment and Ecology, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Qi
authors.affiliation: Institute of Environment and Ecology, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China.
authors.forename: Zhi-Cong
authors.initials: ZC
authors.lastname: Dai
authors.affiliation: World Agroforestry Centre (ICRAF), Central and East Asia Office, Kunming, China; Centre for Mountain Ecosystem Studies (CMES), Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: De-Li
authors.initials: DL
authors.lastname: Zhai
authors.affiliation: Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, Australia.
authors.forename: Si-Chong
authors.initials: SC
authors.lastname: Chen
authors.affiliation: Institute of Environment and Ecology, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China; Department of Biological and Chemical Engineering, Jingdezhen University, Jingdezhen, China.
authors.forename: Chun-Can
authors.initials: CC
authors.lastname: Si
authors.affiliation: Institute of Environment and Ecology, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China; Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education & Jiangsu Province, Jiangsu University, Zhenjiang, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
authors.affiliation: College of Life Sciences, Hainan Normal University, Haikou, China.
authors.forename: Rui-Ping
authors.initials: RP
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Hainan Normal University, Haikou, China.
authors.forename: Qiong-Xin
authors.initials: QX
authors.lastname: Zhong
authors.affiliation: Institute of Environment and Ecology, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China; Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education & Jiangsu Province, Jiangsu University, Zhenjiang, China.
authors.forename: Dao-Lin
authors.initials: DL
authors.lastname: Du
mesh_terms: D019659:Asteraceae / Q000502:physiology*; D044822:Biodiversity; D002681:China; D017753:Ecosystem; D058865:Introduced Species; D018521:Plant Physiological Phenomena