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941.
942.
In present study, several marine water samples collected from the North Goa Beaches, India for isolation of luminescent bacterial species. Isolates obtained labelled as DP1-5 and AB1-6. Molecular characterization including identification of a microbial culture using 16S rRNA gene based molecular technique and phylogenetic analysis confirmed that DP3 & AB1 isolates were Vibrio harveyi. All of the isolates demonstrated multiple metal resistances in terms of growth, with altered luminescence with variable metal concentration. Present investigations were an attempt towards exploring and reporting an updated diversity of bioluminescent bacterial species from various sites around the Goa, India which would be explored in future for constructing luminescence based biosensor for efficiently monitoring the level of hazardous metals in the environment.
Electronic supplementary material
The online version of this article (doi:10.1007/s12088-015-0531-y) contains supplementary material, which is available to authorized users. 相似文献943.
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946.
The aim of the study is to assess the probabilistic non-cancer and cancer risks by recreational bathing in Tres Arroyos creeks (southeastern Buenos Aires Province, Argentina). In these waters, hazardous substances (heavy metals, pesticides) have been detected, possibly related to agricultural activities. To assess such risk, USEPA models in aggregated (exposure through accidental oral water intake and dermal contact simultaneously) and cumulative approaches (combined exposure to more than one substance) were applied, performed for bathers of 5, 10, 15, and 20 years old. The results show that chronic bathing in these waters is not harmful at the concentrations and the exposure scenarios considered. Arsenic was the riskiest substance for both non-cancer and cancer effects, affecting mainly the youngest age group, and the accidental water intake during bathing was the most relevant pathway of exposure. On the other hand, the study highlights the key role of the frequency and duration of the bath event. We discuss the results in light of a previous paper of our authorship concluding that the health risk assessment is a valid alternative to analyze recreational water quality, which, unfortunately, is unused by water management agencies in Argentina. 相似文献
947.
Surface sediment samples were collected from 10 typical locations throughout the Dongting Lake, China, in January 2009. Samples were assayed by atom absorption spectrophotometer and cold atomic fluorescent spectrophotometer for Pb, Cd, As, Hg. In order to investigate the spatial distribution characteristics, sources, and potential ecological risks of heavy metals, the geostatistics method, potential ecological risk index, and multivariate statistical analysis were applied. The results showed that except for the content of Hg, the contents of Pb, Cd, and As had similar spatial distribution characteristics. The average contents of Cd and As exceeded the second class contents of the National Standard for Soil Environment Quality (GB15618-1995), especially that for Cd. The potential ecological risk posed by these heavy metals decreased in the order of the outlet of the Dongting Lake > the East Dongting Lake > the South Dongting Lake > the West Dongting Lake spatially. From the results of multivariate statistical analysis, Pb and Cd, as the first group, were considered to be rooted in mining smelting processes for developed mining and heavy industry. And Hg, as the second group, was mainly derived from parent material weathering, while As was probably considered to originate from both sources above. 相似文献
948.
Thomas Dirnböck Ulf Grandin Markus Bernhardt‐Römermann Burkhardt Beudert Roberto Canullo Martin Forsius Maria‐Theresia Grabner Maria Holmberg Sirpa Kleemola Lars Lundin Michael Mirtl Markus Neumann Enrico Pompei Maija Salemaa Franz Starlinger Tomasz Staszewski Aldona Katarzyna Uziębło 《Global Change Biology》2014,20(2):429-440
Chronic nitrogen (N) deposition is a threat to biodiversity that results from the eutrophication of ecosystems. We studied long‐term monitoring data from 28 forest sites with a total of 1,335 permanent forest floor vegetation plots from northern Fennoscandia to southern Italy to analyse temporal trends in vascular plant species cover and diversity. We found that the cover of plant species which prefer nutrient‐poor soils (oligotrophic species) decreased the more the measured N deposition exceeded the empirical critical load (CL) for eutrophication effects (P = 0.002). Although species preferring nutrient‐rich sites (eutrophic species) did not experience a significantly increase in cover (P = 0.440), in comparison to oligotrophic species they had a marginally higher proportion among new occurring species (P = 0.091). The observed gradual replacement of oligotrophic species by eutrophic species as a response to N deposition seems to be a general pattern, as it was consistent on the European scale. Contrary to species cover changes, neither the decrease in species richness nor of homogeneity correlated with nitrogen CL exceedance (ExCLempN). We assume that the lack of diversity changes resulted from the restricted time period of our observations. Although existing habitat‐specific empirical CL still hold some uncertainty, we exemplify that they are useful indicators for the sensitivity of forest floor vegetation to N deposition. 相似文献
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The deterioration of high quality waters has become an issue of great concern in China. The Chinese government has implemented a series of policies, laws and regulations to control water pollution and improve the surface water quality. However, these measures cannot fundamentally change the status of surface water pollution in China. Some high quality waters have been degraded and do not obtain effective protection. In this paper, we present our views that the lack of antidegradation policy restricts the protection of high quality waters in China. The viewpoint will be beneficial in solving the problem of water pollution in China and also to support other countries in their protection of high quality waters. 相似文献