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111.
Gamma-hexachlorocyclohexane (gamma-HCH or lindane), one of the most commonly used insecticides, has been mainly used in agriculture. Organochloride compounds are known to be highly toxic and persistent, causing serious water and soil pollution. The objective of the present study is the evaluation of the anaerobic degradation of alpha-, beta-, gamma-, delta-HCH in liquid and slurry cultures. The slurry system with anaerobic sludge appears as an effective alternative in the detoxification of polluted soils with HCH, as total degradation of the four isomers was attained. While alpha- and gamma-HCH disappeared after 20-40d, the most recalcitrant isomers: beta- and delta-HCH were only degraded after 102d. Intermediate metabolites of HCH degradation as pentachlorocyclohexane (PCCH), tetrachlorocyclohexene (TCCH), tri-, di- and mono-chlorobenzenes were observed during degradation time.  相似文献   
112.
Laboratory toxicity tests, using ciliated protozoa, are scarce and they have been carried out usually with freshwater species. In this study, we have analysed the acute cytotoxicity of Cd, Zn and Cu in five different strains of very common soil ciliate species (Colpoda steinii, Colpoda inflata and Cyrtolophosis elongata), which were isolated from very different soil samples (polluted or not with heavy metals). Soil ciliates are quite resistant to heavy metals pollution with regard to ciliates from other habitats. The toxicity sequence was Cd>Cu>Zn. Results from Cd+Zn mixtures indicated that Cd cytotoxicity decreases in the presence of low or moderate Zn concentrations. A broad heavy metal resistance level diversity exists among isolates of colpodid ciliates and it is seen to be a genetic feature rather than a habitat dependence. Bioaccumulation is seen to be the main mechanism involved in the metal resistance, except for Cu. For the first time in ciliates, a fluorescent method has been applied to detect Zn intracellular deposits. This methodology might be an useful tool for monitoring heavy metal pollution in soils.  相似文献   
113.
Environmental Science and Pollution Research - Wastewater and effluent discharges are the main causes of receiving water body pollution and important challenges in water quality management. Among...  相似文献   
114.
Environmental Science and Pollution Research - Denitrification and NH3 volatilization are the main removal processes of nitrogen in coastal saline soils. In this incubation study, the effects of...  相似文献   
115.
Hull, a city in the East Riding of Yorkshire, United Kingdom, suffered severe flooding in June 2007, affecting some 8,600 households and most schools. Despite the potential for damage in such disasters, no studies of the effects of floods on teachers and schools in the UK appear to have been published previously. This study analysed the impacts of the floods on teachers in Hull in two stages: first through correspondence with Hull City Council and a mailed questionnaire to 91 head teachers of primary, secondary, and special schools; and second, through in‐depth interviews with head teachers from six flooded schools, representing different degrees of flood experience, and a questionnaire completed by eight teachers from the same schools. The findings reveal the importance and the complexity of the role of the school in the wider community in a time of crisis. The study highlights issues concerning preparedness for floods, support for schools, and flood protection for schools.  相似文献   
116.
Conservation science involves the collection and analysis of data. These scientific practices emerge from values that shape who and what is counted. Currently, conservation data are filtered through a value system that considers native life the only appropriate subject of conservation concern. We examined how trends in species richness, distribution, and threats change when all wildlife count by adding so-called non-native and feral populations to the International Union for Conservation of Nature Red List and local species richness assessments. We focused on vertebrate populations with founding members taken into and out of Australia by humans (i.e., migrants). We identified 87 immigrant and 47 emigrant vertebrate species. Formal conservation accounts underestimated global ranges by an average of 30% for immigrants and 7% for emigrants; immigrations surpassed extinctions in Australia by 52 species; migrants were disproportionately threatened (33% of immigrants and 29% of emigrants were threatened or decreasing in their native ranges); and incorporating migrant populations into risk assessments reduced global threat statuses for 15 of 18 species. Australian policies defined most immigrants as pests (76%), and conservation was the most commonly stated motivation for targeting these species in killing programs (37% of immigrants). Inclusive biodiversity data open space for dialogue on the ethical and empirical assumptions underlying conservation science.  相似文献   
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The switch from hunting wild meat for home consumption to supplying more lucrative city markets in Amazonia can adversely affect some game species. Despite this, information on the amounts of wild meat eaten in Amazonian cities is still limited. We estimated wild meat consumption rates in 5 cities in the State of Amazonas in Brazil through 1046 door-to-door household interviews conducted from 2004 to 2012. With these data, we modeled the relationship between wild meat use and a selection of socioeconomic indices. We then scaled up our model to determine the amounts of wild meat likely to be consumed annually in the 62 urban centers in central Amazonia. A total of 80.3% of all interviewees reported consuming wild meat during an average of 29.3 (CI 11.6) days per year. Most wild meat was reported as bought in local markets (80.1%) or hunted by a family member (14.9%). Twenty-one taxa were cited as consumed, mostly mammals (71.6%), followed by reptiles (23.2%) and then birds (5.2%). The declared frequency of wild meat consumption was positively correlated with the proportion of rural population as well as with the per capita gross domestic product of the municipality (administrative divisions) where the cities were seated. We estimated that as much as 10,691 t of wild meat might be consumed annually in the 62 urban centers within central Amazonia, the equivalent of 6.49 kg per person per year. In monetary terms, this amounts to US$21.72 per person per year or US$35.1 million overall, the latter figure is comparable to fish and timber production in the region. Given this magnitude of wild meat trade in central Amazonia, it is fundamental to integrate this activity into the formal economy and actively develop policies that allow the trade of more resilient taxa and restrict trade in species sensitive to hunting.  相似文献   
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The International Union for Conservation of Nature (IUCN) Red List Index (RLI) is used to measure trends in extinction risk of species over time. The development of 2 red lists for Spanish vascular flora during the past decade allowed us to apply the IUCN RLI to vascular plants in an area belonging to a global biodiversity hotspot. We used the Spanish Red Lists from 2000 and 2010 to assess changes in level of threat at a national scale and at the subnational scales of Canary Islands, Balearic Islands, and peninsular Spain. We assigned retrospective IUCN categories of threat to 98 species included in the Spanish Red List of 2010 but absent in the Spanish Red List of 2000. In addition, we tested the effect of different random and taxonomic and spatial Spanish samples on the overall RLI value. From 2000 to 2010, the IUCN categories of 768 species changed (10% of Spanish flora), mainly due to improved knowledge (63%), modifications in IUCN criteria (14%), and changes in threat status (12%). All measured national and subnational RLI values decreased during this period, indicating a general decline in the conservation status of the Spanish vascular flora. The Canarian RLI value (0.84) was the lowest, although the fastest deterioration in conservation status occurred on peninsular Spain (from 0.93 in 2000 to 0.92 in 2010). The RLI values based on subsamples of the Spanish Red List were not representative of RLI values for the entire country, which would discourage the use of small areas or small taxonomic samples to assess general trends in the endangerment of national biotas. The role of the RLI in monitoring of changes in biodiversity at the global and regional scales needs further reassessment because additional areas and taxa are necessary to determine whether the index is sufficiently sensitive for use in assessing temporal changes in species’ risk of extinction.  相似文献   
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