Biodiv Sci ›› 2020, Vol. 28 ›› Issue (3): 323-332.DOI: 10.17520/biods.2019190

• Original Papers • Previous Articles     Next Articles

Physiological and morphological effects of different canopy densities on reintroduced Acer catalpifolium

Yuyang Zhang1,Tao Yu1,Wenbao Ma2,Fei Wang3,Cheng Tian1,Junqing Li1,*()   

  1. 1. Beijing Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, Beijing 100083
    2. Key Laboratory of National Forestry and Grassland Administration on Sichuan Forest Ecology, Resources and Environment, Sichuan Academy of Forestry Sciences, Chengdu 610081
    3. West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Dujiangyan, Sichuan 611843
  • Received:2019-06-06 Accepted:2019-07-10 Online:2020-03-20 Published:2019-12-24
  • Contact: Junqing Li

Abstract:

The reintroduction of an endangered plant is an effective way to increase its wild plant populations. Suitable habitat is a necessary condition for reintroduced species to survive. Studying the adaptability of a plant’s physiology to different habitats prior to reintroduction is key for evaluating how successful the endangered species would be in each habitat. In this study, Acer catalpifolium, a Wild Plant with Extremely Small Populations (WPESP), was studied to explore the effects of habitat conditions on the morphological traits, photosynthetic characteristics, flavonoid index and chlorophyll contents of A. catalpifolium seedlings. The habitat conditions, no shading, forest edge, gap and understory, are ordered in a gradient from low to high canopy density. The results show that: (1) The change in canopy density correlated with the differences in base diameter, crown width and number of new branches. (2) The maximum single leaf area and single leaf mass were found in the forest edge habitat, and the specific leaf area increased as canopy density increased. (3) With increasing canopy density, intercellular CO2 concentration, transpiration rate and stomatal conductance of A. catalpifolium showed an initial decrease before increasing. In contrast, the flavonoid index showed an initial increase before decreasing. Chlorophyll content showed a consistent upward trend. In summary, the light conditions of forest edge habitat make it more suitable than the other habitats in this study for the reintroduction of A. catalpifolium. This study establishes a theoretical and practical basis for field reintroductions of A. catalpifolium, and provides significant guidance for exploring suitable habitat for the reintroduction of other Wild Plant with Extremely Small Populations.

Key words: Acer catalpifolium, reintroduction in the wild, canopy density, morphological indicators, physiological indicators