Chin J Plant Ecol ›› 2024, Vol. 48 ›› Issue (5): 577-589.DOI: 10.17521/cjpe.2023.0374  cstr: 32100.14.cjpe.2023.0374

Special Issue: 入侵生态学

• Research Articles • Previous Articles     Next Articles

Mechanisms of the invasion of Cenchrus spinifex and drought effects on productivity of Leymus chinensis community

BAI Hao-Ran1,2, HOU Meng1, LIU Yan-Jie1,*()   

  1. 1Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2023-12-14 Accepted:2024-01-23 Online:2024-05-20 Published:2024-01-24
  • Contact: (ecoyj.liu@gmail.com)
  • Supported by:
    Chinese Academy of Sciences Pioneering Young Talent Program(Y9B7041001)

Abstract:

Aims The Leymus chinensis community is one of the most precious natural wealth in China’s grassland resources. However, its productivity is constrained by a variety of global change factors. Although, the invasion of Cenchrus spinifex (hereafter as “invasion”) and drought are two of most important global change factors that significantly affected the productivity of L. chinensis community in the northeast Songnen grassland area, the relevant mechanisms have still not received sufficient attention.

Methods Through the microcosmic control experiments and a complete interaction design with two factors, we explored the mechanism of invasion and drought on the productivity of the L. chinensis community. Factor one was the invasion treatment (invasion vs control), factor two was the water treatment (drought vs normal water), and a total of 10 replications were set up under each treatment, with a total of 40 pots in the experiment.

Important findings The results showed that invasion and drought significantly reduced the aboveground biomass of the L. chinensis community and the dominant species L. chinensis. Soil available nitrogen content and soil arthropod richness significantly decreased under drought treatment, while soil bacterial abundance and arbuscular mycorrhiza fungi (AMF) of the family Glomeraceae increased significantly. The effect of invasion on the effective number of species of soil fungi is moderated by drought, showed that invasion did not affect the effective number of species of soil fungi under normal water conditions, but significantly increased the effective number of species of soil fungi under drought conditions. The results of the structural equation modeling indicated that invasion and drought directly suppressed the L. chinensis community productivity. Drought has indirectly mitigate negative effect on native community productivity by increasing the abundance of dominant soil fungi. In addition, the interaction of invasion and drought suppressed native community productivity by increasing soil fungal community diversity. This study provides a theoretical basis for better protection of grassland productivity and conservation of high-quality forage in the future.

Key words: Cenchrus spinifex, drought, grassland productivity, Leymus chinensis community, plant invasion