Andreu Bonet

Secondary succession of semi-arid Mediterranean old-fields in south-eastern Spain: insights for conservation and restoration of degraded lands

A 60-year chronosequence study of semi-arid old-fields indicates that abandonment age, litter depth, organic carbon soil content, carbonate content and soil moisture are related to vegetation ordination. The species turnover could be high in the recent abandoned fields. Species richness varies, holding a non-linear relation with time as a result of the coexistence of different functional groups. Land use history determines the ordination of communities and previous cropping influences the pathway of succession. Plant functional group and dispersal type richness and cover show significant differences between old-field age groups. The facilitation pathway of crop trees on bird-dispersed shrub species could promote the development of vegetation under these stressful conditions.

Species richness and cover along a 60-year chronosequence in old-fields of southeastern Spain

We analyse changes in plant cover and species richness along a 60-year chronosequence in semi-arid Mediterranean old-fields of southeastern Spain. The objectives were: (i) to study patterns of species richness along the abandonment gradient in semi-arid conditions (e.g., to test the “humped-back model” in our system); (ii) to test whether different broad life forms (annuals, forbs, grasses and woody species) showed different patterns along the abandonment gradient, and (iii) to examine to what extent plants with different dispersal strategies dominate at different stages of succession. The explained variance of the regression relating species richness to years since abandonment is improved when considering different life forms. The results suggest that cover and richness of different functional groups show a non-linear unimodal (often positive-skewed) pattern along the gradient (age since abandonment). Maximum total richness is found at young stages of abandonment (<20 years), when most life forms and dispersal strategies coexist. Annuals and perennial forbs reached their maximum richness during the first 10 years of abandonment. About 45% of total woody species richness is reached at this time as a consequence of early colonization of zoochorous shrubs. While the results showed a tendency towards a life-form replacement sequence, the pattern is not so clear when looking at the different dispersal strategies. The results complement previous results in Mediterranean conditions and emphasise the importance of considering different functional types when studying successional patterns.

Driving Forces of Land-Use Change in a Cultural Landscape of Spain

The aim of this chapter is to examine the processes of change in land cover and land use over the last 44 years, at regional scale, in a traditional, rural south-eastern Spanish catchment. Land use has changed dramatically over recent decades throughout the Mediterranean. Much of this change has been driven by shifts in agricultural and socioeconomic policy. Analysis of aerial photography for the Marina Baixa catchment has revealed a significant decline in traditional agriculture and conversion to forestry or intensive croplands. The consequences of economic globalisation are reflected here in a shift from traditional to intensive agriculture and in human migration from rural to urban areas, as well as in the development of tourism. Land-use changes are correlated with socioeconomic structural forces in order to demonstrate how these changes affect the basic resources of the area and to provide a clearer understanding of possible future trends.

Direct and indirect effects of invasion by the alien tree Ailanthus altissima on riparian plant communities and ecosystem multifunctionality

Most existing studies addressing the effects of invasive species on biodiversity focus on species richness ignoring better indicators of biodiversity and better predictors of ecosystem functioning such as the diversity of evolutionary histories (phylodiversity). Moreover, no previous study has separated the direct effect of alien plants on multiple ecosystem functions simultaneously (multifunctionality) from those indirect ones mediated by the decrease on biodiversity caused by alien plants. We aimed to analyze direct and indirect effects, mediated or not by its effect on biodiversity, of the invasive tree Ailanthus altissima on ecosystem multifunctionality of riparian habitats under Mediterranean climate. We measured vegetation attributes (species richness and phylodiversity) and several surrogates of ecosystem functioning (understory plant biomass, soil enzyme activities, available phosphorous and organic matter) in plots infested by A. altissima and in control (non-invaded) ones. We used structural equation modelling to tease apart the direct and indirect effects of A. altissima on ecosystem multifunctionality. Our results suggest that lower plant species richness, phylodiversity and multifunctionality were associated to the presence of A. altissima. When analyzing each function separately, we found that biodiversity has the opposite effect of the alien plant on all the different functions measured, therefore reducing the strength of the effect (either positive or negative) of A. altissima on them. This is one of the few existing studies addressing the effect of invasive species on phylodiversity and also studying the effect of invasive species on multiple ecosystem functions simultaneously.

Genetic variability modulates the effect of habitat type and environmental conditions on early invasion success of Ailanthus altissima in Mediterranean ecosystems

At the early stages of an invasion by an exotic species, there are diverse environmental and genetic factors that limit its expansion. Ailanthus altissima is a tree from China and northern Vietnam which has become an invasive species in numerous ecosystems around the word. Our objective was to identify the relative effect of both genetic and environmental factors and how they interact with the emergence and early establishment of this invasive tree under Mediterranean conditions. To achieve this, seed germination and early establishment from different maternal sources were analyzed under contrasted environmental conditions in a series of experiments, using both laboratory and field approaches. Seed germination and early survival were affected by environmental factors such as habitat-type, the percentage of bare soil and climatic conditions (rainfall pulses), although the influence of these factors changed depending on the maternal source. Our study reveals that the genetic component affected not only the performance of A. altissima, it also modulated its response to environmental factors, which seemed to be the main drivers of germination and early establishment for this species. Our results highlight the importance of considering both genetic and environmental factors when studying plant invasion risk and success, and may be helpful in predicting and reducing the spread of this species in Mediterranean ecosystems.

CARTOGRAFÍA DE LAS COBERTURAS Y USOS DEL SUELO DE LA MARINA BAIXA (ALICANTE) PARA 1956, 1978 Y 2000

The study of variations through time in land cover and land use as sources of information and geographical diagnosis, is due to many different factors: environmental, economical, social territorial planning (infrastructure, urban or farming planning), strategic research etc., and thus is a key element for decision makers. The analysis of the evolution of land cover and land use through time from a multidisciplinary point of view in the Marina Baixa allows for the evaluation of implemented policy as well as the anticipation of future planning policies. To this effect, we have developed a methodology of spatial data input and management, based on the use of Geographical Information Systems (G.I.S.) and aerial photographs.

Advances in camera trap data management tools: Towards collaborative development and integration with GIS

This project has been carried out thanks to the UNCROACH project (CGL-2011-30581-CC02-01) from the Spanish Ministry of Economy and Competitiveness; and has been partially funded by the public call for research projects of the Conselleria of Education (T6217-2010); and the Institute of Culture Juan Gil-Albert-Alicante.

Conservación de la biodiversidad y uso de las plantas cultivadas en huertos caseros de algunas áreas rurales de Cuba

Con el objetivo de evaluar las potencialidades de los huertos caseros en la conservacion in situ de los recursos geneticos de plantas cultivadas se visitaron 107 huertos caseros, y de ellos se seleccionaron 39 (13-12-14 respectivamente en cada region de Cuba en estudio: occidental, central y oriental). Se observaron en total 508 especies de plantas bajo cultivo con diferentes propositos de uso, las que pertenecen a 352 generos y 108 familias. Las regiones occidental y central poseen un mayor numero de especies comunes al ser comparadas con la region oriental, mientras que el porcentaje mas alto de especies que se encuentra solo en una de las areas de estudio correspondio a la region central. En general las plantas con uso medicinal ocupan una posicion importante dentro de los huertos caseros cubanos, tambien las especies de frutales, de acuerdo al numero de especies observadas. El estudio de las especies claves (Pouteria sapota, Phaseolus lunatus y Capsicum spp.) revelo la existencia de una considerable variabilidad infraespecifica a lo largo de la Isla, manifestandose la necesidad de complementar los mecanismos de conservacion in situ y ex situ. Con la integracion de la informacion socioeconomica, cultural, geografica y de diversidad util obtenida se proponen tres areas efectivas de conservacion in situ de recursos fitogeneticos.

Impacto del tráfico rodado en el P.N. del Carrascal de la Font Roja: ¿cómo influyen las características de la carretera en los atropellos de vertebrados?

The effect of the road CV-797 on the vertebrate community of Carrascal de la Font Roja Natural Park (north of Alicante) during the period 2000-2008 was studied, analysing environmental variables associated with the road and its surroundings, and their relation with the registered roadkills through a multivariate analysis. The distribution of total roadkills is centred on watercourses and four black spots with different composition, which don’t differ much compared to the three found for mammals. The worst affected group are reptiles, while mammal casualties are scarce. Although relationships with environmental variables are species-specific, reptile casualties are associated with areas that are more exposed to solar radiation. Among the birds, the clearest relation is the one between the common sparrow (Passer domesticus) and urban areas, while the rest of the species are roadkilled at their common habitats. Amphibian roadkill is concentrated on two species, thus the relative impact is greater. The small number of mammal casualties does not allow conclusions to be drawn for these species except for the European rabbit (Oryctolagus cuniculus) where roadkill was associated with open areas and crops. It is proposed to continue with sampling so as to better understand the factors which influence roadkills.

Efecto de la procedencia de las bellotas y el morfotipo sobre el éxito de germinación de Quercus coccifera L.

espanolEn el presente trabajo se ha estudiado el efecto de la procedencia y del morfotipo contrastado de plantas madre en el exito de germinacion de bellotas de Quercus coccifera L. Las procedencias que se han seleccionado difieren en las condiciones ambientales y origen geografico en la provincia de Alicante; una se asienta en territorios de clima semiarido con una precipitacion media de 271 mm y la otra presenta un clima subhumedo con una precipitacion media de 833 mm. Se comprueba la hipotesis de que las plantas pueden llegar a mostrar comportamientos morfologicos y fisiologicos diferentes como respuesta adaptativa frente a condiciones ambientales contrastadas, afectando a los procesos de germinacion. En cuanto a los morfotipos, se han seleccionado individuos que presentan diferencias en el tamano foliar de poblaciones de clima semiarido, como caracteristica morfologica indicadora que refleje una respuesta adaptativa frente a las condiciones ambientales locales. Los resultados muestran que existen diferencias entre las poblaciones a nivel de morfotipo, y en cuanto a la procedencia dependiendo de los morfotipos comparados. Tales resultados seran de ayuda para la seleccion de poblaciones o individuos que presenten bellotas de mayor exito de germinacion en tareas previas a la restauracion de zonas degradadas. EnglishThe aim of this paper is to determine the effect of the morphotype constraints and the provenance of Quercus coccifera L. acorns on the germination success. The selected two areas of provenance in the Alicante province (Spain) that have been analysed in this study differ in their environmental conditions and geographical origin: a semiarid area with an average precipitation of 271 mm. and a subhumid area with an average precipitation of 833 mm. The morphotypes analysed in this research have been selected according to the size of the leaves of individuals of populations growing in a semiarid area, for this morphological trait may well be an adaptive response to a particular environment. Our hypothesis is that the adaptive response of plants to different environments can result in significantly different morphological and physiological behaviours, which will in turn have an effect on the germination process. The results suggest that the germination success of acorns produced by different morphotypes vary from one population to another, whereas the effect of the provenance factor depends on the morphotype. Altogether, the evidence of this study can help identify the populations or individuals whose seeds are more likely to germinate successfully, this being an essential preliminary step to the restoration of degraded areas.