Biodiv Sci ›› 2019, Vol. 27 ›› Issue (10): 1047-1055.DOI: 10.17520/biods.2019221

• Original Papers:Plant Diversity •     Next Articles

Elevational patterns of invasive nonnative and native herbaceous species in Jiuwan Mountain National Nature Reserve of Guangxi

Gao Kexiao,Li Feifei,Liu Xiaoyan,Xiong Yunqi,Li Junsheng,Zhao Caiyun()   

  1. Chinese Research Academy of Environmental Sciences, Beijing 100012
  • Received:2019-07-09 Accepted:2019-10-29 Online:2019-10-20 Published:2019-12-20
  • Contact: Zhao Caiyun

Abstract:

Invasive nonnative plants spread rapidly. Many have invaded into national nature reserves and are a threat to biodiversity. Based on a survey of 134 plots of herbaceous species in Jiuwan Mountain National Nature Reserve, we compared spatial distribution patterns of invasive and native herbaceous species diversity and examined the impact of climate factors on these patterns. A total of 143 native herbs were recorded, belonging to 54 families and 115 genera. Another 16 were invasive nonnative herbs, belonging to 7 families and 13 genera. With increasing altitude, species richness and the Shannon-Wiener index of native herbs increased significantly (P < 0.05), whereas that of invasive herbs decreased (P > 0.05). Evenness of neither native herbs nor invasive herbs changed significantly with altitude (P > 0.05). At different altitude gradients, the Shannon-Wiener index of native herbs was significantly higher than that of invasive herbs, but evenness was significantly lower. Regression analysis revealed that 41.6% of variance in native herb richness could be explained by temperature and precipitation (temperature = 21.4% of variance and precipitation = 10.7%), and native herb richness was significantly related to temperature (P < 0.05). Neither temperature nor precipitation was significantly related to invasive herb richness (P > 0.05), and variance explained by these two factors was low (temperature = 0.9% and precipitation = 0.4%). Our results suggest that in Jiuwan Mountain National Nature Reserve, invasive and native species diversity display opposite spatial distribution patterns with altitude, and that climate factors had differential effects on these patterns. Invasive herbs had a relatively diverse community composition and stable community structure at altitudes of 800-1,000 m, which may threaten native herb diversity. We propose that the management of reserves should pay more attention to invasive and nonnative herbs at this altitude range.

Key words: invasive herbs, native herbs, climatic factors, elevational pattern, generalized additive model