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1.
This study examines the effects of recreational use on the soil and vegetation at a site of ecological importance (Nacimiento del Río Mundo, Albacete, Spain). The most visited sites showed increased soil compaction of approximately 50%, bare ground increase to 61 ± 10% and a decrease in richness (from 25 ± 2 to 15 ± 2 species), diversity (from 4.0 ± 0.1 to 2.7 ± 0.4) and stratification of plant species (from 80 ± 11 to 21 ± 4%). The most visited sites had 90% less plant species as compared to the least visited. Intense use was associated with the presence of nitrophilous plant and vegetal species with a morphology adapted to heavy trampling. The recreational areas showed a distribution pattern of impact radiating outwards from the most used and degraded point. At the most visited point, Los Chorros (the spring of the river), the impact radiated outwards for about 20 m. A pilot experiment examining the effects of one-year restriction to visitors for access to a formerly impacted area showed a plant cover increase by anthropic and not by native species of 57 percent units.  相似文献   
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The effects of permethrin (PER) on a panel of antoxidant enzymes; superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and indices of protein oxidation status (carbonylation and free thiols) were determined in digestive gland and gills of the clam Ruditapes decussatus. Animals were exposed to 100 ppb PER for 2 days. These enzyme activities increased significantly in digestive gland (p?<?0.05) after PER treatment and oxidative modification of proteins was detected in both gill and digestive gland extracts using redox proteomics. PER exposure significantly reduced the amount of protein free thiol groups in digestive gland rather than in gill, when compared to controls. Conversely, digestive gland showed significantly higher levels of carbonylated proteins than gill after PER exposure. Some proteins were successfully identified by mass spectrometry of tryptic peptides. Our data suggest that digestive gland of R. decussatus can be used as a model tissue for investigating environmental risk of PER contamination.  相似文献   
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Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade‐tree diversity and shade‐tree carbon stocks in 14 plots of a 35‐ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long‐term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation. Interacciones entre el Secuestro de Carbono y la Diversidad de Árboles de Sombra en una Cooperativa de Café de Pequeños Agricultores en El Salvador  相似文献   
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This work is a part of a wider study involving the economic and environmental implications of managing construction and demolition waste (CDW), focused on the operation of a large scale CDW recycling plant. This plant, to be operated in the Lisbon Metropolitan Area (including the Setúbal peninsula), is analysed for a 60 year period, using primary energy consumption and CO2eq emission impact factors as environmental impact performance indicators.Simplified estimation methods are used to calculate industrial equipment incorporated, and the operation and transport related impacts. Material recycling – sorted materials sent to other industries, to act as input – is taken into account by discounting the impacts related to industrial processes no longer needed.This first part focuses on calculating the selected impact factors for a base case scenario (with a 350 tonnes/h installed capacity), while a sensitivity analysis is provided in part two. Overall, a 60 year global primary energy consumption of 71.4 thousand toe (tonne of oil equivalent) and a total CO2eq emission of 135.4 thousand tonnes are expected. Under this operating regime, around 563 thousand toe and 1465 thousand tonnes CO2eq could be prevented by replacing raw materials in several construction materials industries (e.g.: ferrous and non-ferrous metals, plastics, paper and cardboard).  相似文献   
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Abstract: The links between species–environment relations and species’ responses to protection are unclear, but the objectives of marine protected areas (MPAs) are most likely to be achieved when those relations are known and inform MPA design. The components of a species’ habitat vary with the spatial resolution of the area considered. We characterized areas at two resolutions: 250 m2 (transect) and approximately 30,000 m2 (seascape). We considered three categories of environmental variables: substrate type, bottom complexity, and depth. We sought to determine at which resolution habitat characteristics were a better predictor of abundance and species composition of fishes and whether the relations with environmental variables at either resolution affected species’ responses to protection. Habitat features accounted for a larger proportion of spatial variation in species composition and abundances than differences in protection status. This spatial variation was explained best by habitat characteristics at the seascape level than at the transect level. Species’ responses to protected areas were specific to particular seascape characteristics, primarily depth, and bottom complexity. Our method may be useful for prioritizing marine areas for protection, designing MPAs, and monitoring their effectiveness. It identified areas that provided natural shelter, areas acting as buffer zones, and areas where fish species were most responsive to protection. The identification of such areas is necessary for cost‐effective establishment and monitoring of MPAs.  相似文献   
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Abstract: There is an intense debate about the effects of postfire salvage logging versus nonintervention policies on regeneration of forest communities, but scant information from experimental studies is available. We manipulated a burned forest area on a Mediterranean mountain to experimentally analyze the effect of salvage logging on bird–species abundance, diversity, and assemblage composition. We used a randomized block design with three plots of approximately 25 ha each, established along an elevational gradient in a recently burned area in Sierra Nevada Natural and National Park (southeastern Spain). Three replicates of three treatments differing in postfire burned wood management were established per plot: salvage logging, nonintervention, and an intermediate degree of intervention (felling and lopping most of the trees but leaving all the biomass). Starting 1 year after the fire, we used point sampling to monitor bird abundance in each treatment for 2 consecutive years during the breeding and winter seasons (720 censuses total). Postfire burned‐wood management altered species assemblages. Salvage logged areas had species typical of open‐ and early‐successional habitats. Bird species that inhabit forests were still present in the unsalvaged treatments even though trees were burned, but were almost absent in salvage‐logged areas. Indeed, the main dispersers of mid‐ and late‐successional shrubs and trees, such as thrushes (Turdus spp.) and the European Jay (Garrulus glandarius) were almost restricted to unsalvaged treatments. Salvage logging might thus hamper the natural regeneration of the forest through its impact on assemblages of bird species. Moreover, salvage logging reduced species abundance by 50% and richness by 40%, approximately. The highest diversity at the landscape level (gamma diversity) resulted from a combination of all treatments. Salvage logging may be positive for bird conservation if combined in a mosaic with other, less‐aggressive postfire management, but stand‐wide management with harvest operations has undesirable conservation effects.  相似文献   
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As plants constitute the foundation of the food chain, concerns have been raised about the possibility of toxic concentrations of metals and metalloids being transported from plants to the higher food chain strata. In this perspective, the use of important phytotoxicity endpoints may be of utmost significance in assessing the hazardous nature of metals and metalloids and also in developing ecological soil screening levels. The current study aimed to investigate the role of glutathione (GSH) and its associated enzymes in the metabolic adaptation of two grass species namely Eriophorum angustifolium Honck. and Lolium perenne L. to metals and metalloids stress in the vicinity of a chemical industrial complex (Estarreja, Portugal). Soil and plant samples were collected from contaminated (C) and non-contaminated (reference, R) sites, respectively, near and away from the Estarreja Chemical Complex, Portugal. Soils (from 0 to 10 and 10 to 20 cm depths) were analyzed for pH, organic carbon, and metals and metalloids concentrations. Plant samples were processed fresh for physiological and biochemical estimations, while oven-dried plant samples were used for metals and metalloids determinations following standard methodologies. Both soils and plants from the industrial area exhibited differential concentrations of major metals and metalloids including As, Cu, Hg, Pb, and Zn. In particular, L. perenne shoot displayed significantly higher and lower concentrations of Pb and As, respectively at contaminated site (vs. E. angustifolium). Irrespective of sites, L. perenne shoot exhibited significantly higher total GSH pool, oxidized glutathione (GSSG) and oxidized protein (vs. E. angustifolium). Additionally, severe damages to photosynthetic pigments, proteins, cellular membrane integrity (in terms of electrolyte leakage), and lipid peroxidation were also perceptible in L. perenne shoot. Contrarily, irrespective of the sites, activities of catalase and GSH-regenerating enzyme, GSH reductase, and GSH-metabolizing enzymes such as GSH peroxidase and GSH sulfotransferase were significantly higher in shoot of E. angustifolium. Despite the higher total GSH content, L. perenne is vulnerable to multi-metals-induced stress in comparison to E. angustifolium as depicted by increased GSH- and protein oxidation, low reactive oxygen radical-processing potential (exhibited in terms of low catalase activity) and poor GSH pool utilization efficiency (in terms of lower GSH-associated enzymes activities). The outcome of the present study may be significant for understanding vital GSH-mediated metals and metalloids tolerance mechanisms in plants as well as their unsuitability for animal consumption due to higher metals and metalloids burdens.  相似文献   
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Abstract: Marine protected areas (MPAs) have been highlighted as a means toward effective conservation of coral reefs. New strategies are required to more effectively select MPA locations and increase the pace of their implementation. Many criteria exist to design MPA networks, but generally, it is recommended that networks conserve a diversity of species selected for, among other attributes, their representativeness, rarity, or endemicity. Because knowledge of species’ spatial distribution remains scarce, efficient surrogates are urgently needed. We used five different levels of habitat maps and six spatial scales of analysis to identify under which circumstances habitat data used to design MPA networks for Wallis Island provided better representation of species than random choice alone. Protected‐area site selections were derived from a rarity–complementarity algorithm. Habitat surrogacy was tested for commercial fish species, all fish species, commercially harvested invertebrates, corals, and algae species. Efficiency of habitat surrogacy varied by species group, type of habitat map, and spatial scale of analysis. Maps with the highest habitat thematic complexity provided better surrogates than simpler maps and were more robust to changes in spatial scales. Surrogates were most efficient for commercial fishes, corals, and algae but not for commercial invertebrates. Conversely, other measurements of species‐habitat associations, such as richness congruence and composition similarities provided weak results. We provide, in part, a habitat‐mapping methodology for designation of MPAs for Pacific Ocean islands that are characterized by habitat zonations similar to Wallis. Given the increasing availability and affordability of space‐borne imagery to map habitats, our approach could appreciably facilitate and improve current approaches to coral reef conservation and enhance MPA implementation.  相似文献   
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