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Carrying assorted cargo and covered with paints of varying toxicity, lost intermodal containers may take centuries to degrade on the deep seafloor. In June 2004, scientists from Monterey Bay Aquarium Research Institute (MBARI) discovered a recently lost container during a Remotely Operated Vehicle (ROV) dive on a sediment-covered seabed at 1281 m depth in Monterey Bay National Marine Sanctuary (MBNMS). The site was revisited by ROV in March 2011. Analyses of sediment samples and high-definition video indicate that faunal assemblages on the container’s exterior and the seabed within 10 m of the container differed significantly from those up to 500 m. The container surface provides hard substratum for colonization by taxa typically found in rocky habitats. However, some key taxa that dominate rocky areas were absent or rare on the container, perhaps related to its potential toxicity or limited time for colonization and growth. Ecological effects appear to be restricted to the container surface and the benthos within ∼10 m.  相似文献   
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Environmental monitoring is performed on seafloor communities since these organisms are relatively stationary and integrate the environmental conditions over many years. Standard practices involve sampling by grab. Epifaunal taxa, often missed by grab sampling, are likely to have different ecological functions. We investigate how current environmental assessments represent the benthic community as a whole by comparing taxonomic and functional components sampled by grabs and epibenthic trawls. Faunal communities sampled by trawl (filtrating or predator, epifauna) and grab (infaunal, detrivore) differs widely by sampling distinct functional components, and these may be expected to respond to different human-induced stressors. Neither component appears to be a good surrogate for the community as a whole. We suggest a benthic monitoring by combining both techniques. Sustainable ecosystem functioning is intimately tied to the health of both components of the benthic community, and is recognized as an important goal by signatories of the Convention on Biological Diversity.  相似文献   
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In the late 1950s, Soviet researchers collected benthic infaunal samples from the southeastern Bering Sea shelf. Approximately 17 years later, researchers at University of Alaska Fairbanks also sampled the region to assess infaunal biomass and abundance. Here, the two data sets were examined to document patterns and reveal any consistent differences in infaunal biomass among major feeding groups between the two time periods. No significant differences in the geometric mean biomass of all taxa pooled were indicated between the two study periods (1958–1959=49.1 g m−2; 1975–1976=60.8 g m−2; P=0.14); however, significant differences were observed for specific functional groups, namely carnivores, omnivores and surface detritivores. Of the 64 families identified from both data sets from all functional groups, 21 showed statistically significant (P0.05) differences in mean biomass. Of the 21 families showing significant differences, 19 (91%) of the families had higher mean biomass in the 1975–1976 data set. The above differences suggest a trend toward higher overall infaunal biomass for specific functional groups during mid 1970s compared with the late 1950s. Temperature measurements and literature data indicate that the mid-1970s was an unusually cold period relative to the period before and after, suggesting a mechanistic link between temperature changes and infaunal biomass. Food-web relationships and ecosystem dynamics in the southeastern Bering Sea indicate that during cold periods, infaunal biomass will be elevated relative to warm periods due to elevated carbon flux to the benthos and exclusion of benthic predators on infaunal invertebrates by the cold bottom water on the shelf. As long-term observations of temperature and sea-ice cover indicate a secular warming trend on the Bering Sea shelf, the potential changes in food-web relationships could markedly alter trophic structure and energy flow to apex consumers, potentially impacting the commercial, tourist and subsistence economies.  相似文献   
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The distributions of hydrocarbons and infauna in sediments below a permitted mixing zone for the disposal of treated ballast waters in Port Valdez, Alaska were examined annually, 1999–2001. The associations of biological measures and the abundance of selected benthic organisms to total aromatic hydrocarbons (TARO) ranged up to large-sized effects, as compared against minimum-effect criteria (|r|0.63). The apparent sensitivity of three polychaete worms to low levels of hydrocarbons makes them particularly useful as indicators of future changes in spatial distributions of hydrocarbons associated with discharged effluent. In 2001, sediment TARO concentrations decreased and the correlation values of TARO to biotic variables were generally less than in 1999 and 2000. Evidence supports a conclusion of a strong but spatially limited association of some fauna with accumulations of petroleum hydrocarbons in these sediments.  相似文献   
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