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Butterflies highlight the conservation value of hay meadows highly threatened by land-use changes in a protected Mediterranean area 总被引:1,自引:0,他引:1
Butterfly assemblages were used to characterize and evaluate the conservation value of the main habitat types in the Aiguamolls de l’Empordà Natural Park (north-eastern Spain), an important protected wetland area on the Mediterranean coast. Butterfly data were obtained from a number of transects walked as part of the Catalan Butterfly Monitoring Scheme, which uses a standardized methodology for monitoring butterflies. A Mantel test indicated a strong association between habitat types and the composition of butterfly assemblages and a principal component analysis ordinated individual butterfly species along a gradient from woodland to open areas, thereby indicating various degrees of shade tolerance. In addition, cluster analysis distinguished two main groups of habitats based on the similarities of their butterfly fauna: woodland and bramble clumps and a group of three different kinds of grasslands (traditionally hay meadows, pastures, and alfalfa fields). Hay meadows flooded in winter (the so-called closes) appeared always as the highest ranked habitat in terms of conservation evaluation: they have more butterflies and a slight tendency to harbor more and generally rarer species. This conclusion coincides with that of previous investigations that have indicated that the most diverse and rare plant communities in the whole Natural Park are present in the closes, and highlights the importance of traditionally managed hay meadows for wildlife. However, these hay meadows - one of the rarest habitats in the Mediterranean region - are in alarming decline and have become the most threatened habitat in this protected area: no longer profitable, we believe that the future of the closes will depend ultimately on the existence of agri-environmental schemes. 相似文献
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Pla-Narbona Cludia Stefanescu Constant Pino Joan Cabrero-Saudo Francisco J. Garca-Barros Enrique Munguira Miguel L. Melero Yolanda 《Landscape Ecology》2022,37(1):81-92
Landscape Ecology - Urbanisation is an environmental filter for many species that leads to community homogenisation, with a few species inhabiting isolated patches (e.g. public and private gardens... 相似文献
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Walnut germplasm from three different sites in Oltenia region, located in the southwestern part of Romania, was evaluated to determine the variability and to identify promising types. A total of 64 genotypes were evaluated using morphological characteristics of nuts. Considerable genetic variation in the measured traits was found in native trees which were of seedling origin. Variability found was between 7.62–20.90?g in nut weight, between 31.17 and 53.60?mm in nut length, between 24.81 and 37.48?mm in nut diameter I, and between 23.64 and 36.18?mm in nut diameter II. Separation of the three areas in multivariate space was assessed by calculating the Mahalanobis distance. The highest inter-populations value was observed between Bechet and Ostroveni population (1.83), followed by Sadova and Ostroveni population (1.08), which indicates a wide genetic distance between these populations. Cluster analyses showed a considerable diversity within the same germplasm population. The results indicated that most of genotypes were suitable in terms of morphological traits of nut. These data demonstrated large phenotypic diversity of nut among the selected genotypes that can be considered as a valuable gene stock for breeding programs. 相似文献
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