Life-history traits in an evergreen Mediterranean oak respond differentially to previous experimental environments

Living organisms respond both to current and previous environments, which can have important consequences on population dynamics. However, there is little experimental evidence based on long-term field studies of the effects of previous environments on the performance of individuals. We tested the hypothesis that trees that establish under different environmental conditions perform differently under similar post-establishment conditions. We used the slow-growing, evergreen Mediterranean oak <i>Quercus ilex</i> subsp. <i>rotundifolia</i> as target species. We analyzed the effects of previous environments, competition effects and tradeoffs among life-history traits (survival, growth, and reproduction). We enhanced seedling establishment for three years by reducing abiotic environmental harshness by means of summer irrigation and artificial shading in 12 experimental plots, while four plots remained as controls. Then these treatments were interrupted for ten years. Seedlings under ameliorated environmental conditions survived and grew faster during early establishment. During the post-management period, previous treatments 1) did not have any effect on survival, 2) experienced a slower above-ground growth, 3) decreased root biomass as indicated from reflectivity of Ground Penetration Radar, 4) increased acorn production mostly through a greater canopy volume and 5) increased acorn production effort. The trees exhibited a combination of effects related to acclimation for coping with abiotic stress and effects of intra-specific competition. In accordance with our hypothesis, tree performance overall depended on previous environmental conditions, and the response was different for different life-history traits. We recommend early management because it increased plot cover, shortened the time to attain sexual maturity and increased the amount of acorn production. Plots such as those assessed in this study may act as sources of propagules in deforested agricultural landscapes thus aiding natural establishment of new plants

Monitoring land cover change of the dryland forest landscape of Central Chile (1975–2008)

Las figuras que contiene el documento se localizan al final del mismo.Land cover and its configuration in the landscape are crucial components in the provision of biodiversity and ecosystem services. In Mediterranean regions, natural landscapes mostly covered by evergreen vegetation have been to a large extent transformed into cultural landscapes since long time ago. We investigated land cover changes in Central Chile using multi-temporal satellite imagery taken in 1975, 1985, 1999 and 2008. The major trends in this highly dynamic landscape were reduction of dryland forest and conversion of shrubland to intensive land uses such as farmland. The average net annual deforestation rate was −1.7%, and shrubland reduction occurred at an annual rate of −0.7%; agriculture, urban areas and timber plantations increased at annual rates of 1.1%, 2.7% and 3.2%, respectively, during the 1975–2008 period. Total forest and shrubland loss rates were partly offset by passive revegetation. However, most of the areas that were passively revegetated remained as shrubland and did not turn into forests due to a low capacity of forest recovery. This resulted in a progressive loss and degradation of dryland forest over the entire region. Overall, the documented land cover changes increase provisioning services such as crops, cattle, and timber that are characteristic of cultural landscapes in the area but may cause an irreversible loss of biodiversity and a depletion of other ecological services provided by forests and shrubland. The implications for conservation of this area and the need for territorial planning and adapted land-use strategies are discussed

Factors influencing vegetation cover change in Mediterranean Central Chile (1975-2008)

Las figuras y apéndices que contiene el documento se localizan al final del mismo.Questions: Which are the factors that influence forest and shrubland loss and regeneration and their underlying drivers?\ud \ud Location: Central Chile, a world biodiversity hotspot.\ud \ud Methods: Using land-cover data from the years 1975, 1985, 1999 and 2008, we fitted classification trees and multiple logistic regression models to account for the relationship between different trajectories of vegetation change and a range of biophysical and socio-economic factors.\ud \ud Results: The variables that most consistently showed significant effects on vegetation change across all time-intervals were slope and distance to primary roads. We found that forest and shrubland loss on one side and regeneration on the other often displayed opposite patterns in relation to the different explanatory variables. Deforestation was positively related to distance to primary roads and to distance within forest edges and was favoured by a low insolation and a low slope. In turn, forest regeneration was negatively related to the distance to primary roads and positively to the distance to the nearest forest patch, insolation and slope. Shrubland loss was positively influenced by slope and distance to cities and primary roads and negatively influenced by distance to rivers. Conversely, shrubland regeneration was negatively related to slope, distance to cities and distance to primary roads and positively related to distance from existing forest patches and distance to rivers.\ud \ud Conclusions: This article reveals how biophysical and socioeconomic factors influence vegetation cover change and the underlying social, political and economical drivers. This assessment provides a basis for management decisions, considering the crucial role of perennial vegetation cover for sustaining biodiversity and ecosystem services.This work was financed by the REFORLAN Project, INCO Contract CT2006-032132 (European Commission), with additional input from projects CGL2010-18312 (Spanish Ministry of Science and Innovation) and S2009AMB-1783 (Madrid Government REMEDINAL-2). We are in-\ud debted to Javier Salas and Cristian Echeverría for their input in this project. The manuscript benefited from\ud useful comments from Jorge Aubad and two anonymous\ud reviewers, who improved the contents and presentation\ud of this stud

Geographic patterns of vertebrate diversity and identification of relevant areas for conservation in Europe

The ‘EU Council conclusions on biodiversity post–2010′ re–enforced Europe’s commitment to halt biodiversity loss by 2020. Identifying areas of high–value for biodiversity conservation is an important issue to meet this target. We investigated the geographic pattern of terrestrial vertebrate diversity status in Europe by assessing the species richness, rarity, vulnerability (according to IUCN criteria), and a combined index of the three former for the amphibians, reptiles, bird and mammals of this region. We also correlated the value of all indices with climate and human influence variables. Overall, clear geographic gradients of species diversity were found. The combined biodiversity index indicated that high–value biodiversity areas were mostly located in the Mediterranean basin and the highest vulnerability was found in the Iberian peninsula for most taxa. Across all indexes, the proportion of variance explained by climate and human influence factors was moderate to low. The results obtained in this study have the potential to provide valuable support for nature conservation policies in Europe and, consequently, might contribute to mitigate biodiversity decline in this region

The differential influences of human-induced disturbances on tree regeneration community: a landscape approach

Understanding the processes shaping biological communities under interacting disturbances is\ud a core challenge in ecology. Although the impacts of human-induced disturbances on forest ecosystems have\ud been extensively studied, less attention has been paid to understanding how tree regeneration at the\ud community level responds to such disturbances. Moreover, these previous studies have not considered how\ud these effects change according to major social and environmental factors that can influence forest use at a\ud landscape scale. In this study, we investigate the effects of cattle grazing and selective logging on the\ud composition of tree regeneration communities in relation to forest successional stage and land tenure regime\ud in Chilean temperate forests, a global biodiversity hotspot. We recorded seedlings, saplings and basal area of\ud stumps of tree species (as a surrogate for selective logging), and number of cattle dung pats (as a surrogate\ud for cattle pressure) in 129 25 3 20 m plots in small (,200 ha) and large properties in different successional\ud stages (old-growth, intermediate, secondary forests). The regeneration of the ten more abundant species as\ud predicted by human disturbance, land tenure, forest successional stage, and number of parent trees was\ud modelled using generalised linear models. Predictions for each individual model were made under different\ud scenarios of human disturbance. The predicted regeneration results were assembled and subjected to\ud ordination analyses and permutation multivariate analyses of variance to determine differences in\ud regeneration composition under each scenario. In most cases, best-fit models contained at least one of the\ud explanatory variables accounting for human disturbance. The effects of selective logging on tree regeneration\ud varied depending on land tenure regime, but cattle grazing always exhibited a negative effect. Our results\ud revealed that cattle have a more negative effect on forest regeneration than selective logging, especially in\ud old-growth forests and small properties. Our analytical approach contributes to the understanding of the\ud differential influence of human-induced disturbances on the tree regeneration community at a landscape\ud scale. It can inform conservation policies and actions, which should focus on addressing themain disturbance\ud factors and on developing strategies to conserve the most sensitive species to such disturbances.C. Zamorano-Elgueta was supported by a CON-\ud ICYT pre-doctoral fellowship (Government of Chile),\ud the European Comission (Project contract DCI-ENV/\ud 2010/222-412), the Chilean NGO Forest Engineers for\ud Native Forest (Forestales por el Bosque Nativo, www.\ud bosquenativo.cl) and project REMEDINAL-2 (Comu-\ud nidad de Madrid, S2009/AMB-1783). L. Cayuela was\ud supported by project REMEDINAL-2. This work is\ud part of the objectives of projects CGL2010-18312\ud (CICYT, Ministerio de Economı́a y Competividad de\ud Espana). The authors acknowledge the valuable\ud support of Vero ́nica Pı́riz, Cony Becerra, Rodrigo\ud Gangas, Oscar Concha, Eduardo Neira and staff from\ud the Valdivian Coastal Reserve, as well as the National\ud Forest Service of Chile (Corporación Nacional Forestal

Effects of land use on nocturnal birds in a Mediterranean agricultural landscape.

Abstract. Knowledge on the effects of land use on community composition and species abundance is crucial for designing realistic conservation strategies, particularly in highly dynamic systems such as Mediterranean agricultural mosaics that are subjected to intensive cultivation. We investigated these effects on the nocturnal bird species occurring in the study area (Stone Curlew Burhinus oedicnemus, Red-necked Nightjar Caprimulgus ruficollis, Barn Owl Tyto alba, Eurasian Scops Owl Otus scops, Little Owl Athene noctua, Tawny Owl Strix aluco, Long-eared Owl Asio otus, Short-eared Owl Asio flammeus and Eagle Owl Bubo bubo) across an agricultural-natural habitat mosaic in Central Spain for three consecutive years. Shares of vineyards, scrubland, herbaceous cropland, water bodies, and roads significantly affected the composition of the nocturnal bird community. Herbaceous cropland and olive groves, which covered 50% of the study area, proved to be neutral for all species. Remnant patches of natural and semi-natural scrubland (around 10% of the study area) and water bodies (only 1.5% of the study area) showed a positive effect on Eagle Owls, Eurasian Scops Owls, Long-eared Owls, and Red-necked Nightjars. Vineyard (35% of the study area) had a negative influence on Eagle Owls, Long-eared Owls, and Eurasian Scops Owls. Our results indicate, first, that the relative extent of land use types was apparently not related with the presence of nocturnal bird species and, second, that natural scrublands and water bodies are key habitats for assuring the persistence of nocturnal birds in agricultural Mediterranean landscapes. Current land planning focused toward land use intensification will likely increase the areas of habitats that are neutral or have adverse effects on nocturnal birds

An assessment of the causes and consequences of agricultural land abandonment in Europe

The agriculture sector is the principal source of income for around 20% of the EU-26 population, which live in predominantly rural regions that would be devastated without its contribution. Moreover, the combined agricultural and food sector forms an important part of the EU economy, accounting for 15 million jobs (8.3% of total employment) and 4.4% of GDP. The 12 million active farmers across Europe today, have an average farm size of about 15 ha, and are expected to meet the needs of 500 million Europeans. In addition, they are also expected to promote a sustainable and balanced development of their land, also in areas where production conditions are difficult. Yet, despite the relevance of the sector, the use of land for agriculture purposes is not very sustainable. Among other issues, there is a serious problem in respect of the abandonment of agricultural land. Based on the perceived need for research on this topic, the aim of this paper is to examine the causes and consequences of agricultural land abandonment, outlining its social, economic and environmental impacts, as well as the implications for territorial integration

Gravel pits support waterbird diversity in an urban landscape

We assessed the benefit of 11 gravel pits for the settlement of waterbird communities in an urbanized area lacking natural wetlands. Gravel pits captured 57% of the regional species pool of aquatic birds. We identified 39 species, among which five were regionally rare. We used the Self Organizing Map algorithm to calculate the probabilities of presence of species, and to bring out habitat conditions that predict assemblage patterns. The age of the pits did not correlate with assemblage composition and species richness. There was a positive influence of macrophyte cover on waterbird species richness. Larger pits did not support more species, but species richness increased with connectivity. As alternative wetland habitats, gravel pits are attractive to waterbirds, when they act as stepping stones that ensure connectivity between larger natural and/or artificial wetlands separated in space

Restoration of Ailing Wetlands

The science of ecological restoration involves building the technical understanding needed to restore damaged ecosystems, such as wetlands, which provide critical services needed to support human health and economic well-being

Toward integrated analysis of human impacts on forest biodiversity: lessons from Latin America.

Although sustainable forest management (SFM) has been widely adopted as a policy and management goal, high rates of forest loss and degradation are still occurring in many areas. Human activities such as logging, livestock husbandry, crop cultivation, infrastructural development, and use of fire are causing widespread loss of biodiversity, restricting progress toward SFM. In such situations, there is an urgent need for tools that can provide an integrated assessment of human impacts on forest biodiversity and that can support decision making related to forest use. This paper summarizes the experience gained by an international collaborative research effort spanning more than a decade, focusing on the tropical montane forests of Mexico and the temperate rain forests of southern South America, both of which are global conservation priorities. The lessons learned from this research are identified, specifically in relation to developing an integrated modeling framework for achieving SFM. Experience has highlighted a number of challenges that need to be overcome in such areas, including the lack of information regarding ecological processes and species characteristics and a lack of forest inventory data, which hinders model parameterization. Quantitative models are poorly developed for some ecological phenomena, such as edge effects and genetic diversity, limiting model integration. Establishment of participatory approaches to forest management is difficult, as a supportive institutional and policy environment is often lacking. However, experience to date suggests that the modeling toolkit approach suggested by Sturvetant et al. (2008) could be of value in such areas. Suggestions are made regarding desirable elements of such a toolkit to support participatory-research approaches in domains characterized by high uncertainty, including Bayesian Belief Networks, spatial multi-criteria analysis, and scenario planning.Most of the research described here was undertaken in three projects supported by the European Commission (INCO programme), namely SUCRE (ERBIC18CT970146), BIOCORES (ICA4- CT-2001-10095), and ReForLan (INCO-DEV-3 N° 032132), and three Darwin Initiative (DEFRA, UK Government) grants to the senior author. Additional funding was provided by a variety of sources within the partner countries. All sources of financial support are gratefully acknowledged