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671.
Journal of Polymers and the Environment - Bioactive biodegradable films are emerging biomaterials in the food packaging field. This study aims to investigate the effect of different Cenostigma...  相似文献   
672.
Environmental Fluid Mechanics - The sudden increase in air temperature associated with strong gusty winds of northerly direction is a phenomenon occasionally observed during the cold season in the...  相似文献   
673.
Environmental Science and Pollution Research - Algal organic matter (AOM) in water reservoirs is a worldwide concern for drinking water treatment; once it is one of the main precursors for...  相似文献   
674.
Environmental Science and Pollution Research - Rhizosphere bacteria, for example, rhizobia, can play several roles, and one of the most important, the protection of plant roots against toxic...  相似文献   
675.
Environmental Science and Pollution Research - The presence of microplastics in the sea is a global issue widely studied and discussed in the last years. The whole marine ecosystem is now...  相似文献   
676.
Environmental Science and Pollution Research - In this work, graphene oxide (GO) was synthesized by the modified Hummers method. The nanomaterial was characterized by FTIR and Raman spectroscopy,...  相似文献   
677.
Environmental Science and Pollution Research - This paper discussed the possibility of replacing the internal combustion engine of the series plug-in hybrid electric vehicle (PHEV) powered by...  相似文献   
678.
The effect of predation on artificial reef juvenile demersal fish species   总被引:1,自引:0,他引:1  
There is a concern that artificial reefs (AR) may act purely as fishing aggregation devices. Predators attracted to ARs can influence the distribution and abundance of prey fish species. Determining the role of predators in AR is important in advancing the understanding of community interactions. This paper documents the effects of predation on fish assemblages of AR located near a coastal lagoon fish nursery. The Dicentrarchus labrax is a very opportunistic species preying on juveniles (0+ and 1+ age classes) of several demersal fish species on the ARs. Reef prey and sea bass abundance were negatively correlated. The mean numbers of prey per sea bass stomach increased with the increase of reef fish prey abundance, suggesting that predation has a significant influence, resulting in a decrease in prey abundance. Prey mortality (4–48%) of demersal reef fish associated species depends on bass density. Prey selection was related both with prey abundance and vulnerability. Results showed that D. labrax predation on AR-fish associated species can increase prey natural mortality. However, the role of bass predation on the ecological functioning of exploited ARs is not clear. There may be increases in local fishing yields due either to an increase in predator biomass through aggregation of sea bass attracted to ARs or to greater production. In contrast, predation on juveniles of economically important reef fish preys, especially the most frequent and abundant (Boops boops), can contribute to a decrease in recruitment to the fishery. Our results indicate that inter-specific interactions (predator–prey) are important in terms of conservation and management, as well as for the evaluation of the long-term effects of reef deployment. Thus, it is necessary to consider ecological interactions, such as predation, prior to the development and deployment of artificial habitats as a tool for rehabilitation.  相似文献   
679.
The aim of this work is to investigate the activity of the antioxidant enzyme superoxide dismutase in the cosmopolitan sponge Cliona celata (Grant, 1826), since this enzyme has been described as a useful biomarker for marine pollution in other marine invertebrates. The quantification of the catalytic activity for superoxide dismutase is quite complex because its substrate is an unstable free radical. Several methods have been developed for this enzymatic activity determination; most of them are based on inhibition of a redox reaction involving the superoxide radical. In this work, two methods are compared, for crude sponge extracts, as far as repeatability, reproducibility and sensibility are concerned. The adrenaline oxidation method seems to be the most adequate for these determinations. Statistical treatment of the data indicates that the reference value for the specific superoxide dismutase activity in C. celata should be in the interval [0–535.5] U/mg of total protein in wet tissues, for normal populations.  相似文献   
680.
The genus Nyctiphanes (Malacostraca, Euphausiacea) comprises four neritic species that display antitropical geographic distribution in the Pacific (N. simplex and N. australis) and Atlantic (N. couchii and N. capensis) Oceans. We studied the origin of this distribution applying methods for phylogenetic reconstruction and molecular dating of nodes using a Bayesian MCMC analysis and the DNA sequence information contained in mtDNA 16S rDNA and cytochrome oxidase (COI). We tested hypotheses of vicariance by contrasting the time estimates of cladogenesis with the onset of the major barriers to ocean circulation. It was estimated that Nyctiphanes originated in the Pacific Ocean during the Miocene, with a lower limit of 18 miilion years ago (Mya). An Atlantic–Pacific cladogenic event (95% HPD 3.2–9.6) took place after the closure of the Tethyan Sea, suggesting that dispersal occurred from the Indo-Pacific, most likely via southern Africa. Similarly, the antitropical distribution pattern observed in the eastern Atlantic Ocean likely resulted from recent Pliocene–Pleistocene (95% HPD 1.0–4.97) northward dispersal from the southern hemisphere. Our results imply that dispersal appears to have had a significant role to play in the evolution of this group. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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