4 resultados para Transnational advocacy networks, Biodiversity and CyberPolitics
em Repositório Científico da Universidade de Évora - Portugal
Resumo:
Aim Positive regional correlations between biodiversity and human population have been detected for several taxonomic groups and geographical regions. Such correlations could have important conservation implications and have been mainly attributed to ecological factors, with little testing for an artefactual explanation: more populated regions may show higher biodiversity because they are more thoroughly surveyed. We tested the hypothesis that the correlation between people and herptile diversity in Europe is influenced by survey effort
Resumo:
Sediment digging is an anthropogenic activity connected to the exploitation of living resources in estuarine and marine environments. The knowledge on the functional responses of the benthic assemblages to the physical disturbance is an important baseline to understand the ecological processes of the habitat recovery and restoration and to develop tools for the management of the harvesting activities. To investigate the effects of the digging activity of the bivalves on Zostera noltii seagrass beds a manipulative field experiment was conducted that included the enzymatic activity of sediments and the associated nematode assemblages. Four plots (two undisturbed serving as control and two dug to collect bivalves - treatment) with 18 subplots were randomly located at seagrass beds in the Mira estuary at the SW coast of Portugal. Samples were randomly and unrepeatably collected from three subplots of each plot in five different occasions, before sediment digging (T0) up to six months after disturbance (T5). Microbial activity in sediments was assess by determining the extracelular enzymatic activity of six hydrolytic enzymes (sulfatase, phosphatase, b -N-acetilglucosaminidase, b-glucosidase, urease, protease) and two oxidoreductases (phenol oxidase and peroxidase). The microbial community status was also assessed through the measurement of dehydrogenase, which reflects microbial respiration. The nematode assemblages composition, biodiversity and trophic composition at different sampling occasions were also analyzed. The fluorometric and biochemical parameters analysed of the Z. noltii plants during the experimental period showed a recovery of the seagrass beds, and it was detected an increase of the enzymatic activity of the sediments after disturbance. The nematodes assemblages were similar in all sampling occasions. The seagrass beds and the nematodes assemblages associated showed a high resilience to the stress caused by the traditional bivalves digging activity. The obtained results allow the development of a management programme for the commercial fishing activity to maintain the good environmental status and minimized the secondary environmental effects on marine and estuarine habitats through the establishment of a baseline for the regulation of the harvesting frequency.
Resumo:
The tribe Longidorini within the subfamily Longidorinae (Longidorus spp. and Paralongidorus spp.) and the subfamily Xiphineminae (Xiphinema spp.) are two large nematode groups with about 260 and 230 known species, respectively. They are globally two important groups of ectoparasitic nematodes considered to be major pests because of their activity as vectors of important plant nepovirus, with some species included in the list of quarantine pathogenic organisms in many European countries. Knowledge of the biodiversity and occurrence of this nematode group is a prerequisite for the establishment of sound management strategies and control measures. According to data collected from the databases (such as EPPO, FSTA, and Web of Science) and published in specialised literature, a total of 15 Longidorus, 1 Paralongidorus and 40 Xiphinema species have been recorded as present in Portugal. However, the taxonomic status of some species is controversial, and thus needs to be clarified. A comprehensive review for unravelling the biodiversity and occurrence of nematode species of the genus Longidorus, Paralongidorus and Xiphinema in Portugal is herein provided. This review includes an updated checklist of species with information on the localities, host plants and geographical distribution. Additionally, maps on the species distributions of Longidorinae and Xiphineminae nematodes present in Continental Portugal and the Portuguese Macaronesian islands are provided, as well as unpublished data on authors and comments on the current taxonomic status. Finally, new insights and directions for future research on Longidoridae in Portugal are presented.
Resumo:
Non-perennial rivers and streams (NPRS) cover >50% of the global river network. They are particularly predominant in Mediterranean Europe as a result of dry climate conditions, climate change and land use development. Historically, both scientists and policy makers underestimated the importance of NRPS for nature and humans alike, mainly because they have been considered as systems of low ecological and economic value. During the past decades, diminishing water resources have increased the spatial and temporal extent of artificial NPRS as well as their exposure to multiple stressors, which threatening their ecological integrity, biodiversity and ecosystem services. In this paper, we provide a comprehensive overview of the structural and functional characteristics of NPRS in the European Mediterranean, and discuss gaps and problems in their management, concerning their typology, ecological assessment, legislative and policy protection, and incorporation in River Basin Management Plans. Because NPRS comprise highly unstable ecosystems, with strong and often unpredictable temporal and spatial variability - at least as far as it is possible to assess - we outline the future research needs required to better understand, manage and conserve them as highly valuable and sensitive ecosystems. Efficient collaborative activities among multidisciplinary research groups aiming to create innovative knowledge, water managers and policy makers are urgently needed in order to establish an appropriate methodological and legislative background. The incorporation of NPRS in EU-Med River Basin Management Plans in combination with the application of ecological flows is a first step towards enhancing NPRS management and conservation in order to effectively safeguard these highly valuable albeit threatened ecosystems