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排序方式: 共有333条查询结果,搜索用时 15 毫秒
331.
Joshua G. Smith Christopher M. Free Cori Lopazanski Julien Brun Clarissa R. Anderson Mark H. Carr Joachim Claudet Jenifer E. Dugan Jacob G. Eurich Tessa B. Francis Scott L. Hamilton David Mouillot Peter T. Raimondi Richard M. Starr Shelby L. Ziegler Kerry J. Nickols Jennifer E. Caselle 《Global Change Biology》2023,29(19):5634-5651
Marine protected areas (MPAs) have gained attention as a conservation tool for enhancing ecosystem resilience to climate change. However, empirical evidence explicitly linking MPAs to enhanced ecological resilience is limited and mixed. To better understand whether MPAs can buffer climate impacts, we tested the resistance and recovery of marine communities to the 2014–2016 Northeast Pacific heatwave in the largest scientifically designed MPA network in the world off the coast of California, United States. The network consists of 124 MPAs (48 no-take state marine reserves, and 76 partial-take or special regulation conservation areas) implemented at different times, with full implementation completed in 2012. We compared fish, benthic invertebrate, and macroalgal community structure inside and outside of 13 no-take MPAs across rocky intertidal, kelp forest, shallow reef, and deep reef nearshore habitats in California's Central Coast region from 2007 to 2020. We also explored whether MPA features, including age, size, depth, proportion rock, historic fishing pressure, habitat diversity and richness, connectivity, and fish biomass response ratios (proxy for ecological performance), conferred climate resilience for kelp forest and rocky intertidal habitats spanning 28 MPAs across the full network. Ecological communities dramatically shifted due to the marine heatwave across all four nearshore habitats, and MPAs did not facilitate habitat-wide resistance or recovery. Only in protected rocky intertidal habitats did community structure significantly resist marine heatwave impacts. Community shifts were associated with a pronounced decline in the relative proportion of cold water species and an increase in warm water species. MPA features did not explain resistance or recovery to the marine heatwave. Collectively, our findings suggest that MPAs have limited ability to mitigate the impacts of marine heatwaves on community structure. Given that mechanisms of resilience to climate perturbations are complex, there is a clear need to expand assessments of ecosystem-wide consequences resulting from acute climate-driven perturbations, and the potential role of regulatory protection in mitigating community structure changes. 相似文献
332.
The aim of this study is to analyse the structural characteristics, educational level, professed religion, composition of
the family nucleus in Italy and in the home country, and work conditions in Italy and in the home country, in order to describe
the anthropological stress of the sample of immigrants examined. A series of questions was given to Albanian population immigrating
to the province of Bari after 1991, Albanian refugees of 1997, Chinese population resident in Bari, and a sample of immigrants
in Metaponto, regarding their specific motives for immigration. 相似文献
333.
Ludvik M. Gomulski Cristina Torti Mariangela Bonizzoni Daniela Moralli Elena Raimondi Pierre Capy Giuliano Gasperi Anna R. Malacrida 《Journal of molecular evolution》2001,53(6):597-606
Several copies of highly related transposable elements, Crmar2, Almar1, and Asmar1, are described from the genomes of Ceratitis rosa, Anastrepha ludens, and A. suspensa, respectively. One copy from C. rosa, Crmar2.5, contains a full-length, uninterrupted ORF. All the other copies, from the three species contain a long deletion within the putative ORF. The consensus Crmar2 element has features typical of the mariner/Tc1 superfamily of transposable elements. In particular, the Crmar2 consensus encodes a D,D41D motif, a variant of the D,D34D catalytic domain of mariner elements. Phylogenetic analysis of the relationships of these three elements and other members of the mariner/Tc1 superfamily, based on their encoded amino acid sequences, suggests that they form a new basal subfamily of mariner elements, the rosa subfamily. BLAST analyses identified sequences from other diptera, including Drosophila melanogaster, which appear to be members of the rosa subfamily of mariner elements. Analyses of their molecular evolution suggests that Crmar2 entered the genome of C. rosa in the recent past, a consequence of horizontal transfer. 相似文献