The use of stable isotope measurements can help in our understanding of relationships between plants and their environment, like the strategies for plant-resource acquisition, plant interactions with other organisms, and influence of plant species on soil functioning. Carbon isotopic ratio (ð 13C) is a useful index for assessing intrinsic water use efficiency (WUE), i.e. the ratio of carbon acquired to water vapor losses via stomatal conductance. Values more negative of ð 13C are associated with a lower WUE. Natural nitrogen isotopic ratio (ð15N) in soils and plants is used for studying the transformation of nitrogen compounds in soils, determining the sources of nitrogen for plants, and assessing the contribution of symbiotic nitrogen fixation to the nitrogen budget of ecosystems. This work aims to analyze the effects of different afforested tree species growing under common environmental conditions in the Guadiamar Green Corridor, after a mine-spill and subsequent soil clean-up and remediation. Seven species with contrasted leaf habit were selected: three deciduous (Populus alba, Celtis australis, Fraxinus angustifolia) and four evergreen (Quercus ilex, Olea europaea, Ceratonia siliqua and Pinus pinea) The isotopic composition of carbon and nitrogen was analyzed in plant tissues and in the soil underneath at different depths. We tested the differences among tree species as well as the differences among plant tissues and soil depth and their implications on nitrogen and carbon cycles of the ecosystem.

Communication presented in the session "Stable isotopes in ecology" at the 4th Iberian Congress of Ecology, Coimbra (Portugal), 16-19 June 2015.

Peer reviewed