How do Light and Water Acquisition Strategies Affect Species Selection during Secondary Succession in Moist Tropical Forests?

Forests

Leonie Schönbeck²  Madelon Lohbeck²  Frans Bongers²  Miguel Martínez Ramos¹  Frank Sterck² 

[1] Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Campus Morelia, Antigua Carretera a Pátzcuaro 8701, Ex-hacienda de San José de la Huerta, Morelia, Michoacán 58190, Mexico; E-Mail:;Forest Ecology and Forest Management Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands; E-Mails:

关键词: Chiapas;    environmental filtering;    Evaporative flux method;    functional traits;    leaf drought tolerance;    leaf shade tolerance;    Mexico;    secondary succession;    tropical moist forest;    vulnerability;   

DOI  :  10.3390/f6062047

来源: mdpi

【 摘 要 】

Pioneer tree species have acquisitive leaf characteristics associated with high demand of light and water, and are expected to be shade and drought intolerant. Using leaf functional traits (specific leaf area, photosynthetic rate, relative water content and stomatal conductance) and tree performance (mortality rate) in the field, we assessed how shade and drought tolerance of leaves are related to the species’ positions along a successional gradient in moist tropical forest in Chiapas, Mexico. We quantified morphological and physiological leaf shade and drought tolerance indicators for 25 dominant species that characterize different successional stages. We found that light demand decreases with succession, confirming the importance of light availability for species filtering during early stages of succession. In addition, water transport levels in the leaves decreased with succession, but high water transport did not increase the leaf’s vulnerability to drought. In fact, late successional species showed higher mortality in dry years than early successional ones, against suggestions from leaf drought tolerance traits. It is likely that pioneer species have other drought-avoiding strategies, like deep rooting systems and water storage in roots and stems. More research on belowground plant physiology is needed to understand how plants adapt to changing environments, which is crucial to anticipate the effects of climate change on secondary forests.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.