Landscape structure shapes carnivore-mediated seed dispersal kernels

Context Seed dispersal is recognized as having profound effects on the distribution, dynamics and structure of plant populations and communities. However, knowledge of how landscape structure shapes carnivore-mediated seed dispersal patterns is still scarce, thereby limiting our understanding of large-scale plant population processes. Objectives We aim to determine how the amount and spatial configuration of forest cover impacted the relative abundance of carnivorous mammals, and how these effects cascaded through the seed dispersal kernels they generated. Methods Camera traps activated by animal movement were used for carnivore sampling. Colour-coded seed mimics embedded in common figs were used to know the exact origin of the dispersed seed mimics later found in carnivore scats. We applied this procedure in two sites differing in landscape structure. Results We did not find between-site differences in the relative abundance of the principal carnivore species contributing to seed dispersal patterns, Martes foina. Mean dispersal distance and the probability of long dispersal events were higher in the site with spatially continuous and abundant forest cover, compared to the site with spatially aggregated and scarcer forest cover. Seed deposition closely matched the spatial patterning of forest cover in both study sites, suggesting behaviour-based mechanisms underpinning seed dispersal patterns generated by individual frugivore species. Conclusions Our results provide the first empirical evidence of the impact of landscape structure on carnivore-mediated seed dispersal kernels. They also indicate that seed dispersal kernels generated strongly depend on the effect that landscape structure exerts on carnivore populations, particularly on habitat-use preferences.

Urban public policies: towards the improvement of landscape ecological system. The case-study of the city of Évora, Portugal.

The Charter of European Planning 2013 presents a Vision for the future of European cities and regions, highlighting the sustainability of cities and the preservation of urban ecosystems, integrating the man-made environment with the natural ecosystems and contribute to the well-being and quality of life of their inhabitants and other stakeholders. Thus, urban public policies are crucial to the improvement of the landscape ecological system, achievable by city planning and design. The paper aims to analyse if public urban policies in Portugal have been integrating strategies and/or guidelines to enhance the ecological system of the landscape. Then, which new perspectives are possible, framed by the recently approved law Bases of Public Policy of Soils, Land Management and Urban Planning (2014). This new law, in contrast with the previous ones, don’t allow reserving land to urbanize, in municipal master plans. Moreover, it is possible to revert land classified for urban purposes in those plans into rustic soils (when it is not yet infra-structured or built). It allows creating new planning and design dynamics, convert several areas and including them in the urban ecological structure, essential to the enhancement of landscape ecological system. This is a filed of work where landscape architecture has huge responsibilities, by associating and harmonize man-made environment with natural systems, enlightening sustainability consistent with conservation and improvement of Nature while contributing to the well-being and quality of life of Man. A sustainability that is ethical, aesthetic, ecological and cultural. The study is supported by a case study – the city of Évora. The ultimate goal is to propose measures to promote larger and better integration of ecological component in urban public policies, framed by the new territorial management law, taking into account and highlighting the specificities of the landscape system – Man and Nature – at the local level.

Hierarchical spatial segregation of two Mediterranean vole species: the role of patch‑network structure and matrix composition

According to ecological theory, the coexistence of competitors in patchy environments may be facilitated by hierarchical spatial segregation along axes of environmental variation, but empirical evidence is limited. Cabrera and water voles show a metapopulation-like structure in Mediterranean farmland, where they are known to segregate along space, habitat, and time axes within habitat patches. Here, we assess whether segregation also occurs among and within landscapes, and how this is influenced by patch-network and matrix composition. We surveyed 75 landscapes, each covering 78 ha, where we mapped all habitat patches potentially suitable for Cabrera and water voles, and the area effectively occupied by each species (extent of occupancy). The relatively large water vole tended to be the sole occupant of landscapes with high habitat amount but relatively low patch density (i.e., with a few large patches), and with a predominantly agricultural matrix, whereas landscapes with high patch density (i.e.,many small patches) and low agricultural cover, tended to be occupied exclusively by the small Cabrera vole. The two species tended to co-occur in landscapes with intermediate patch-network and matrix characteristics, though their extents of occurrence were negatively correlated after controlling for environmental effects. In combination with our previous studies on the Cabrera-water vole system, these findings illustrated empirically the occurrence of hierarchical spatial segregation, ranging from withinpatches to among-landscapes. Overall, our study suggests that recognizing the hierarchical nature of spatial segregation patterns and their major environmental drivers should enhance our understanding of species coexistence in patchy environments.