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The establishment and development of oak ( Quercus spp.) seedlings are frequently impaired by site heterogeneity resulting from historical anthropogenic disturbances in Mediterranean basin woodlands. In particular, the alteration of forest structure and soil biotic and abiotic components can compromise the natural regeneration of Persian oak ( Quercus brantii Lindl.) in western Iran. This study aimed to investigate how soil properties, soil mesofauna diversity and stand structural indices differ between well and poorly regenerated areas. We sampled 105 plots in an oak woodland subjected to past disturbances but protected from human activities for the last 20 years. These 100-m 2 plots were distributed into two groups: i) poorly regenerated plots (PRP) with only 0 or 1 newly established oak seedling, and ii) well regenerated plots (WRP) with ≥3 seedlings. In each plot, we characterized the forest structure using three structural indices, and determined the soil properties and mesofauna diversity. Structural indices were higher in WRP than in PRP for height (0.83 and 0.23), diameter differentiation (0.74 and 0.36) and species mixture (0.90 and 0.21). Also, richness and diversity of soil mesofauna were lower in PRP than in WRP.A canonical correspondence analysis (CCA) ordination clearly separated WRP, which were characterized by a clumped spatial distribution of mature oak trees on fertile soils, from PRP that exhibited a uniform spatial distribution of trees established on soils with a higher sand content (63 and 59%) and a higher bulk density (1.7 and 1.3).The uniform spatial distribution of trees, which was less favourable to oak seedling establishment, was inherited from intensive past human disturbances. To favour oak regeneration, we recommend applying management actions in cooperation with land-users, in particular the conservation of small patches of tree clumps to act as islands of fertility and seed sources. [ABSTRACT FROM AUTHOR]

Background: A previous multi-locus lineage (MLL) analysis of SSR-microsatellite data of old olive trees in the southeast Mediterranean area had shown the predominance of the Souri cultivar (MLL1) among grafted trees. The MLL analysis had also identified an MLL (MLL7) that was more common among rootstocks than other MLLs. We here present a comparison of the MLL combinations MLL1 (scion)/MLL7 (rootstock) and MLL1/MLL1 in order to investigate the possible influence of rootstock on scion phenotype. Results: A linear regression analysis demonstrated that the abundance of MLL1/MLL7 trees decreases and of MLL1/MLL1 trees increases along a gradient of increasing aridity. Hypothesizing that grafting on MLL7 provides an advantage under certain conditions, Akaike information criterion (AIC) model selection procedure was used to assess the influence of different environmental conditions on phenotypic characteristics of the fruits and oil of the two MLL combinations. The most parsimonious models indicated differential influences of environmental conditions on parameters of olive oil quality in trees belonging to the MLL1/MLL7 and MLL1/MLL1 combinations, but a similar influence on fruit characteristics and oil content. These results suggest that in certain environments grafting of the local Souri cultivar on MLL7 rootstocks and the MLL1/MLL1 combination result in improved oil quality. The decreasing number of MLL1/MLL7 trees along an aridity gradient suggests that use of this genotype combination in arid sites was not favoured because of sensitivity of MLL7 to drought. Conclusions: Our results thus suggest that MLL1/MLL7 and MLL1/MLL1 combinations were selected by growers in traditional rain-fed cultivation under Mediterranean climate conditions in the southeast Mediterranean area. [ABSTRACT FROM AUTHOR]

Abstract: We assessed the linkages between environmental variables and the spatio-temporal distribution patterns of larval abundance of coastal fish assemblages within and outside the Medes Islands marine protected area (MPA; NW Mediterranean) to explore possible fisheries effects such as larvae export of the latter. We analyzed small-scale fish larvae distribution of 28 representative taxa from the rocky fish assemblage and combined the former in different groups with the help of cluster analysis. Further we assessed the influence of selected abiotic variables on group and species distributions using Generalized Additive Models (GAM’s). We found a high level of variability in the response of larvae groups and species to environmental variables over the two studied periods (spring and summer); depth and habitat of the adults being the most important factors. In addition, distance to the MPA was found as an important variable in defining the location of larvae of strictly coastal species. Our results provided evidence of larval export of three commercial species affected by the MPA (Epinephelus marginatus, Pagellus erythrinus and Scorpaena porcus). Thus our study contributes to the few empirical assessments of larvae export from MPAs and adds to the understanding of the functioning of MPAs as fisheries management tools. Nevertheless, in the future integrated assessments of fisheries effects of MPAs are required that measure the effect of larvae and biomass export on increased fishing yield while taking into account fishing effort dynamics. [Copyright &y& Elsevier]

Hydrological and hydrodynamic characteristics are important controls in all wetlands including coastal lagoons. Enhanced understanding of lagoon functioning can be obtained through the acquisition and interpretation of hydrological, meteorological and related data. The MELMARINA Project investigated links between hydrological and ecological conditions within North African coastal lagoons. It employed three primary sites: Merja Zerga in Morocco, Ghar El Melh in Tunisia and Lake Manzala in Egypt. Hydrological, meteorological and related data were acquired for these lagoons. Data included precipitation, evaporation, wind speed and direction, freshwater discharges into the lagoons, tides beyond the lagoons in the open sea, lagoon bathymetry and time series of lagoon water levels/depths. Data were acquired from secondary sources (including online archives) and targeted field survey and monitoring programmes. Interpretation of these data provides insights into the hydrological functioning of the lagoons and contributed to the modelling requirements of MELMARINA. The functioning of Merja Zerga is dominated by the exchange of water between the Atlantic and the lagoon. Large, tidally induced oscillations in water level are responsible for the inundation of extensive inter-tidal mudflats whilst the rapid replacement of water by exchanges with the sea diminishes the influence of freshwater inflows and winter rainfall. The smaller Mediterranean tides reduce the magnitude of lagoon–sea exchanges and result in much smaller water level oscillations within Ghar El Melh. As a result, this lagoon lacks the inter-tidal environments found within the Moroccan site and hydrodynamic conditions are more likely influenced by wind set up. Although freshwater inflows to Ghar El Melh are smaller than those in Merja Zerga, their effects, coupled with heavy winter rainfall, can persist due to longer residence times of water within the lagoon. Freshwater inflows are central to the... [ABSTRACT FROM AUTHOR]