Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (8): 844-859.DOI: 10.17521/cjpe.2020.0311

• Research Articles • Previous Articles     Next Articles

Characteristics of Distylium chinense communities and their relationships with soil environmental factors in different water level fluctuation zones of the Three Gorges Reservoir, China

HUANG Jie1,2, LI Xiao-Ling1,2,*, WANG Xue-Song1,2, YANG Jin1,2, HUANG Cheng-Ming3   

  1. 1College of Biological and Pharmaceutical Science of China Three Gorges University, Yichang, Hubei 443002, China
    2Engineering Research Center of Eco- environment in the Three Gorges Reservoir Region, Ministry of Education, Hubei International Scientific and Technological Center of Ecological Conservation and Management in the Three Gorges Area, Yichang, Hubei 443002, China
    3Three Gorges Botanical Garden, Yichang, Hubei 443111, China
  • Received:2020-09-17 Revised:2021-05-28 Online:2021-08-20 Published:2021-06-28
  • Contact: LI Xiao-Ling
  • Supported by:
    National Natural Science Foundation of China(51209122);National Natural Science Foundation of China(51779127)

Abstract:

Aims Distylium chinense is endemic to central China, and can be dominant species in parts of the Three Gorges Reservoir area. Studying the characteristics of D. chinense communities and their relationships with soil environmental factors under different habitat conditions could help gain knowledge assisting the community protection and vegetation restoration in the water level fluctuation zone of the Three Gorges Reservoir.
Methods Measurements were made on species composition, floristic characteristics, and plant diversity in D. chinense communities in 24 plots (4 m × 4 m) covering six study sites across the water level fluctuation zone of the Three Gorges Reservoir. The relationships of varying community traits with soil environmental factors were determined by quantitative classification and ordination methods.
Important findings A total of 56 plant species were recorded across the 24 sampling plots, belonging to 36 families and 54 genera. The plant communities mainly composed of the cosmopolitan species, pantropical and north temperate of D. chinense community, predominantly as herbs and shrubs. In the natural water level fluctuation zone, D. chinense scored the highest importance value in the shrub layer, and Ficus tikoua in the herb layer. The companion species of D. chinense commumities were shrubs and perennial herbs with flooding tolerance, such as Swida paucinervis, F. tikoua, Imperata cylindrica, etc. However, in the off-season water level fluctuation zone, D. chinense was the only plant in the shrub layer, with dominance of Cynodon dactylon in the herb layer and other companion species as annual herbs, such as Xanthium sibiricum, Abutilon theophrasti, etc. Two-way cluster analysis divided the six sites into four community types: D. chinense + S. paucinervis, D. chinense + F. tikoua, D. chinense + Adina rubella, and D. chinense + C. dactylon. Canonical correspondence analyses showed that altitude and soil pH were the main environmental factors affecting the species distribution of D. chinense community, followed by the content of soil organic matter, total phosphorus, total nitrogen, and available potassium, which were the main influencing factors of species diversity index with nitrogen being the limiting factor. In rehabilitation of the off-season water level fluctuation zones of the Three Gorges Reservoir, small shrubs such as A. rubella and S. paucinervis should be used as the companion species of the upper slopes with increased supply of soil nitrogen and potassium, in order to promote higher species diversity of the D. chinense community and to maintain the stability of water level fluctuation zone ecosystems.

Key words: the Three Gorges Reservoir area, Distylium chinense, community characteristics, soil environmental factors, canonical correspondence analysis