Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (8): 951-960.DOI: 10.17521/cjpe.2021.0267

• Research Articles • Previous Articles     Next Articles

Dominance of different plant life forms in the typical steppe evidenced from impacts of environmental factors on chlorophyll

ZHENG Ning1,3, LI Su-Ying1,3,*(), WANG Xin-Ting1,3, LÜ Shi-Hai2, ZHAO Peng-Cheng1,3, ZANG Chen1,3, XU Yu-Long1, HE Jing1, QIN Wen-Hao1, GAO Heng-Rui1   

  1. 1College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot 010051, China
    2Institute of Ecological Environment, Chinese Research Academy of Environmental Sciences, Beijing 100020, China
    3Key Laboratory of Environmental Pollution Control and Remediation at Universities of Inner Mongolia Autonomous Region, Hohhot 010051, China
  • Received:2021-07-16 Accepted:2022-01-12 Online:2022-08-20 Published:2022-08-20
  • Contact: LI Su-Ying
  • Supported by:
    Natural Science Foundation of Nei Mongol(2020MS03078);National Natural Science Foundation of China(32060251);National Key R&D Program of China(2018YFC0507304)


Aims This study aimed to understand whether the coupling between environmental factors and chlorophyll contents is related to the dominance of plant life forms in the grasslands.

Methods In July 2020, we measured chlorophyll contents in 185 plant samples from 50 forage species of 11 sampling plots of a typical steppe in Xilinhot. Through correlation analysis, single factor analysis of variance, redundancy analysis (RDA), stepwise regression analysis and path analysis, we analyzed the effects of multiple environmental factors on indices of plant chlorophyll and the mechanism underlying the competition advantage of different plant species.

Important findings 1) The contents of chlorophyll a and chlorophyll b were significantly positively correlated with that of total chlorophyll, with the correlation coefficients of 0.807 and 0.936, respectively. The contents of total chlorophyll were more affected by that of chlorophyll b. 2) The contents of chlorophyll a, chlorophyll b, and total chlorophyll of the four life forms followed an order of semi-shrubs > perennial grasses > annual or biennial plants > perennial forbs. 3) The variations of chlorophyll contents among plant life forms were differently explained by environmental factors. The RDA results showed that the explanatory degree of semi-shrubs was the highest (28.0%), followed by annual or biennial plants (18.3%) and perennial forbs (17.7%), and that of perennial grasses was the lowest (12.7%). 4) The chlorophyll index of plant life forms were affected by various environmental factors. The chlorophyll b contents in semi-shrubs were affected by soil organic carbon content and relative air humidity, while their total chlorophyll contents were mainly influenced by relative air humidity. Chlorophyll b contents of perennial forbs were mainly restricted by surface temperature. The contents of chlorophyll a, chlorophyll b, and total chlorophyll of annual or biennial species were mainly affected by soil pH. 5) Path analysis results showed that chlorophyll a contents of grasses were mainly affected by soil factors, chlorophyll b and total chlorophyll contents were mainly impacted by atmospheric factors in the grassland habitats. Comparatively, perennial grasses were not susceptible to environmental factors so that they become more tolerant to environmental changes than the other life forms. Therefore, these plants gradually became dominant during community succession and evolution.

Key words: typical steppe, environmental factor, chlorophyll content, redundancy analysis, plant types