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Calama R.,CIFOR INIA | Calama R.,Instituto Universitario Of Gestion Forestal Sostenible | Manso R.,French National Institute for Agricultural Research | Barbeito I.,French National Institute for Agricultural Research | And 10 more authors.
Applied Ecology and Environmental Research | Year: 2015

Inter-specific difference in seed size is one of the main factors influencing regeneration strategies in plant species. The classical trade-off theory postulates that the species with larger seeds produce smaller amounts of offspring that colonize fewer microsites, although a large amount of reserves permits seeds to germinate and survive in a broader range of conditions. Contrarily, the species with smaller seeds are assumed to widely disseminate their seeds, attaining lower rates of seedling establishment and survival. We tested this hypothesis by analysing regeneration traits in Pinus pinea L. (large-seeded species, average seed weight: 700 mg, SD: ±200 mg) and Pinus sylvestrais L. (small-seeded species: average seed weight: 13 mg, SD: ±4.2 mg). We used data from regeneration trials in inland Spain to analyse five different attributes: 1) seed production and masting habit, 2) seed shadow, 3) annual pattern of emergence and seed success, 4) spatial pattern of seedling emergence, and 5) seedling survival. Our results show that those attributes defining the spatial pattern of regeneration in both species match the assumptions related to their seed size. However, when these species grow under limiting environments, the annual pattern of emergence and seedling survival does not follow the expected trade-off theory. © 2015, ALÖKI Kft., Budapest, Hungary. All rights reserved.

Sustainable territorial management requires reliable assessment of the impact of conservation policies on landscape structure and dynamics. Euro-Mediterranean regions present a remarkable biodiversity which is linked in part to traditional land use practices and which is currently threatened by global change. The effectiveness of one-decade conservation policies against land use changes was examined in Central Spain (Madrid Autonomous Community). A Markov model of landscape dynamics was parameterized with CORINE Land Cover information and transition matrices were obtained. The methods were applied in both protected and unprotected areas to examine whether the intensity and direction of key land use changes -urbanisation, agricultural intensification and land abandonment- differed significantly depending on the protection status of those areas. Protected areas experienced slower rates of agricultural intensification processes and faster rates of land abandonment, with respect to those which occurred in unprotected areas. It illustrates how simple mathematical tools and models -parameterized with available data- can provide to managers and policy makers useful indicators for conservation policy assessment and identification of land use transitions.

Santos-del-Blanco L.,University of Lausanne | Santos-del-Blanco L.,Instituto Universitario Of Gestion Forestal Sostenible | Climent J.,CIFOR INIA | Climent J.,Instituto Universitario Of Gestion Forestal Sostenible
Journal of Ecology | Year: 2014

Summary: Costs of reproduction lie at the core of basic ecological and evolutionary theories, and their existence is commonly invoked to explain adaptive processes. Despite their sheer importance, empirical evidence for the existence and quantification of costs of reproduction in tree species comes mostly from correlational studies, while more comprehensive approaches remain missing. Manipulative experiments are a preferred approach to study cost of reproduction, as they allow controlling for otherwise inherent confounding factors like size or genetic background. Here, we conducted a manipulative experiment in a Pinus halepensis common garden, removing developing cones from a group of trees and comparing growth and reproduction after treatment with a control group. We also estimated phenotypic and genetic correlations between reproductive and vegetative traits. Manipulated trees grew slightly more than control trees just after treatment, with just a transient, marginally non-significant difference. By contrast, larger differences were observed for the number of female cones initiated 1 year after treatment, with an increase of 70% more cones in the manipulated group. Phenotypic and genetic correlations showed that smaller trees invested a higher proportion of their resources in reproduction, compared with larger trees, which could be interpreted as an indirect evidence for costs of reproduction. Synthesis. This research showed a high impact of current reproduction on reproductive potential, even when not significant on vegetative growth. This has strong implications for how we understand adaptive strategies in forest trees and should encourage further interest on their still poorly known reproductive life-history traits. © 2014 British Ecological Society.

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