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991.
Joana Garrido Nogueira Ronaldo Sousa Hassan Benaissa Geert De Knijf Sónia Ferreira Mohamed Ghamizi Duarte V. Gonçalves Richard Lansdown Catherine Numa Vincent Prié Nicoletta Riccardi Mary Seddon Maria Urbańska Alice Valentini Ilya Vikhrev Simone Varandas Amílcar Teixeira Manuel Lopes-Lima 《Conservation biology》2021,35(5):1367-1379
Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species that trigger either the vulnerability and or the irreplaceability criterion and thus identify a site as a KBA). However, to our knowledge, many of these KBAs have not been validated. Therefore, classical surveys of the taxa used to identify freshwater KBAs (fishes, molluscs, odonates, and aquatic plants) were conducted in Douro (Iberian Peninsula) and Sebou (Morocco) River basins in the Mediterranean Biodiversity Hotspot. Environmental DNA analyses were undertaken in the Moroccan KBAs. There was a mismatch between the supposed and actual presence of trigger species. None of the trigger species were found in 43% and 50% of all KBAs surveyed in the Douro and Sebou basins, respectively. Shortcomings of freshwater KBA identification relate to flawed or lack of distribution data for trigger species. This situation results from a misleading initial identification of KBAs based on poor (or even inaccurate) ecological information or due to increased human disturbance between initial KBA identification and the present. To improve identification of future freshwater KBAs, we suggest selecting trigger species with a more conservative approach; use of local expert knowledge and digital data (to assess habitat quality, species distribution, and potential threats); consideration of the subcatchment when delineating KBAs boundaries; thoughtful consideration of terrestrial special areas for conservation limits; and periodic field validation. 相似文献
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Salas-Zapata Walter Posada-Castaño Anny Mejía-Durango Diana 《The Environmentalist》2021,41(4):487-500
Environment Systems and Decisions - Natural resources are a type of good whose individual utility maximization is not desirable, as it could lead to their depletion. This problem, raised several... 相似文献
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Paula?Adánez SanjuánEmail author Belinda?Flem Juan?F.?Llamas Borrajo Juan?Locutura Rupérez Angel?Garcia Cortés 《Environmental geochemistry and health》2016,38(2):449-468
Changes in the principal sources of Pb in overbank sediment profiles have been documented for two Spanish areas by using Pb isotopes and Pb concentrations. These locations (Madrid and Tinto–Odiel basin) represent two of the most contaminated regions in Spain. The Community of Madrid is characterized by heavy industrial and urban activity, focused mainly in Madrid City. The Tinto–Odiel basin drains the Iberian Pyrite Belt, which hosts many polymetallic massive sulphides and is heavily affected by mining activities in their headwaters. It has been proven that the influence of anthropogenic activity is reflected in these overbank deposits by variations in Pb concentrations that, in general, correlate with shifts in the 206Pb/207Pb ratio. Rivas profile (downstream of Madrid) was found to be the most anthropogenically influenced site. The sediments within this profile which were recently deposited (170 ± 40 years BP) have the least radiogenic signatures. 206Pb/207Pb ratios ranged between 1.1763 and 1.1876 indicating significant contributions of anthropogenic Pb. In contrast, profiles upstream of Madrid possess an average 206Pb/207Pb ratio of 1.2272. It is difficult to clearly identify the most prominent source as the sediments appear to be characterized by an input from several sources. The floodplain profiles in the Tinto–Odiel basin exhibit uniform 206Pb/207Pb ratios ranging from 1.1627 (Odiel river) to 1.1665 (Tinto river). These ratios are similar to the ones possessed by sulphide ores in the area and differ from the ratios of other nonmineralized formations in the basin, indicating that mining activities are the primary, if not sole, source of Pb to the sediments. 相似文献
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Morton-Bermea Ofelia Beramendi-Orosco Laura Martínez-Reyes Ángeles Hernández-Álvarez Elizabeth González-Hernández Galia 《Environmental geochemistry and health》2016,38(1):195-202
Environmental Geochemistry and Health - Tree rings may be used as indicators of contamination events providing information on the chronology and the elemental composition of the contamination. In... 相似文献
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Cellular damage of plant pathogenic fungi by antifungal compounds produced by Bacillus spp. isolates
Estibaliz Sansinenea Mauro Almaraz Maria Dolores Ramírez Aurelio Ortiz 《Chemistry and Ecology》2016,32(8):722-732
The use of microorganisms as biological control agents (BCAs) has become an effective alternative to chemical means of controlling plant pathogens. The antagonistic and inhibitory activity of 71 Bacillus spp. strains, which were isolated from different Mexican sites, were tested against several phytopathogen fungi, Fusarium oxysporum, Fusarium equiseti, Fusarium avenaceum, Bipolaris spp. and Alternaria spp. From the antagonism study, the strain ELI149 showed a marked inhibition of growth against all tested fungi; therefore crude metabolites from this strain were extracted using ethyl acetate and amberlite resin and probed against the same fungi as well as strains of Mucor sp., Penicillium spp. and Paecilomyces spp. The results indicated that amberlite was more suitable for extraction of secondary metabolites with antifungal activity. Finally, observation of cell damage in the tested pathogenic fungi showed marked morphological changes on reproductive structures in all tested fungi indicating that antibiosis was the mechanism of the antagonistic effect. These results suggest that metabolites from the Bacillus strains have a wide spectrum of antibiotic activities, which can be used as biocontrol agents for controlling fungal plant diseases of agricultural importance. 相似文献