Tree structure and growth in wetland forests along a hydrological gradient in southern Europe
In forested wetlands, hydrology exerts complex and sometimes compensatory influences on tree growth, particularly in semi-arid ecosystems, where water can be both a limiting resource and a stressor. We are studying the effects of site waterlogging and edaphic controls (soil nutrient content and texture) on the density, growth patterns and overall productivity of forested wetlands dominated by alder (Alnus glutinosa) and willow (Salix atrocinerea) in coastal Portugal and Spain. We are using dendrochronology to compare radial growth in trees between sites with varying levels of waterlogging, and between trees showing various degrees of ‘shrubbiness,’ or multi-stemmed architecture. Understanding whether flooding is a subsidy or stress to wetland trees in this arid region is important in considering the conservation value of these rare forests and the impacts of human modifications to natural hydrology.
Related publication: (* indicates student contributors)
Rodríguez-González, P.M.*, J.C. Stella, F. Campelo, T. Ferreira, A. Albuquerque. 2010. Subsidy or stress? Tree structure and growth in wetland forests along a hydrological gradient in southern Europe. Forest Ecology and Management 259: 2015–2025. DOI:10.1016/j.foreco.2010.02.012. [pdf]