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241.
Urbanization is a key driver of global biodiversity loss. Although sub-Saharan African countries are experiencing unprecedented urbanization and urban expansion, very little is known about how this impacts tropical biodiversity. Here, we assessed the effects of urban expansion and urban green space on local small mammal species diversity in Accra, Ghana. We surveyed small mammals in the University of Ghana botanical garden, an urban green area (UGA) and adjoining built-up environment (BE) and compared the results with baseline data (BLD) collected when large areas of the current city still remained mostly undeveloped. The methodology involved live-trapping using Sherman collapsible live-traps. Our data showed higher small mammal abundance and diversity in the UGA than BE. Similarity of species composition was higher between UGA and BLD than between BE and BLD. The small mammal species captured in BE (the rodents Mastomys erythroleucus, Rattus rattus, and Arvicanthis rufinus, and the shrew Crocidura olivieri) are known to easily adapt to human-modified landscapes. Our results suggest that urbanization negatively influenced the abundance, diversity, and community composition of small mammals. Efforts should be directed towards the integration of urban green areas into urban land development planning in developing countries in order to conserve local wildlife and ecological services that enhance the quality of urban life.  相似文献   
242.
Regional Environmental Change - The published online version contains mistake. Anna Maria Jönsson was inadvertently omitted in the author group section. Correct author group section is shown...  相似文献   
243.
The oil industry is a major source of contamination in Peru, and wastewater and sediments containing oil include harmful substances that may have acute and chronic effects. This study determined polycyclic aromatic hydrocarbon (PAH) concentrations by GC/MS, mutagenicity using TA98 and TA100 bacterial strains with and without metabolic activation in the Muta-ChromoPlate? test, and Microtox® 5-min EC50 values of Peruvian crude oil, and water and sediment pore water from the vicinity of San José de Saramuro on the Marañón River and Villa Trompeteros on the Corrientes River in Loreto, Peru. The highest total PAH concentration in both areas was found in water (Saramuro?=?210.15 μg/ml, Trompeteros?=?204.66 μg/ml). Total PAH concentrations in water from San José de Saramuro ranged from 9.90 to 210.15 μg/ml (mean?=?66.48 μg/ml), while sediment pore water concentrations ranged from 2.19 to 70.41 μg/ml (mean?=?24.33 μg/ml). All water samples tested from Saramuro and Trompeteros sites, and one out of four sediment pore water samples from Trompeteros, were found to be mutagenic (P?<?0.001). One sediment pore water sample in Saramuro was determined to have a measurable toxicity (Microtox EC50?=?335.1 mg/l), and in Trompeteros, the EC50 in water and sediment pore water ranged from 25.67 to 133.86 mg/l. Peruvian crude oil was mutagenic using the TA98 strain with metabolic activation, and the EC50 was 17.18 mg/l. The two areas sampled had very high PAH concentrations that were most likely associated with oil activities, but did not lead to acute toxic effects. However, since most of the samples were mutagenic, it is thought that there is a greater potential for chronic effects.  相似文献   
244.
Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723?±?0.448 mg/L and 0.032?±?0.012 mg/L, respectively. The mean cobalt concentration was 0.071?±?0.049 mg/L, while the mean Zn concentration in the samples was 0.060?±?0.097 mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178?±?0.091 mg/L and 0.053?±?0.063 mg/L respectively. About 78 % of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3 mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005 mg/L prescribed for cadmium. About 91 % of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks.  相似文献   
245.
To attempt to determine the effects of temperature and salinity on the dynamics of the dinoflagellate community, a monthly sampling was carried out from October 2008 to March 2009 at eight sampling stations in Ghar El Melh Lagoon (GML; Mediterranean Sea, Northern Tunisia). Dinoflagellates were dominant among plankton, accounting for 73.9 % of the lagoon’s overall plankton community, and were comprised of 25 different species among which 17 were reported in the literature as harmful. While no significant difference was found in the distribution of dinoflagellates among the stations, a strong monthly difference was observed. This temporal variability was due to an increase in the abundance of Prorocentrum micans from December to February, leading to a strong decrease in the Shannon diversity index from station to station. At the onset of P. micans development, dinoflagellate abundances reached 1.26.105 cells l?1. A redundance analysis indicates that both temperature and salinity have a significant effect on the dynamics of the dinoflagellate community. Using a generalized additive model, both temperature and salinity appear to have significant nonlinear relationships with P. micans abundances. Model predictions indicate that outbreaks of P. micans may occur at a temperature below 22.5 °C and with salinity above 32.5. We discuss our results against a backdrop of climate change which, by affecting temperature and salinity, is likely to have an antagonistic impact on P. micans development and subsequently on the dinoflagellate dynamics in GML.  相似文献   
246.
Much of the terrestrial biodiversity in sub-Saharan Africa is supported by tropical rainforest. Natural resource development, particularly surface mining in the rainforest, poses great risks to the region’s rich and endemic biodiversity. Here, we assessed the impact of surface mining and the success of forest rehabilitation on small mammal diversity in the Western Region of Ghana. We surveyed small mammals in the project area and two adjoining forest reserves (control sites) before the mining operation and 10 years after mine closure and forest rehabilitation (topsoil replacement and revegetation). The forest reserves recorded higher species abundance than the mining areas. Majority of the species captured in the forest reserves, including Hylomyscus alleni, Praomys tullbergi, Malacomys cansdalei, and Hybomys trivirgatus, are forest obligate species. Only one individual each of H. alleni and P. tullbergi was captured in the naturally regenerated areas (core areas of mining activities that were allowed to revegetate naturally), while 32 individuals belonging to four species (Lophuromys sikapusi, Mus musculoides, Mastomys erythroleucus, and Crocidura olivieri) were recorded in the rehabilitated areas. Our data suggested negative effects of mining on small mammal diversity and the restoration of species diversity and important ecological processes after rehabilitation of altered habitats. We strongly encourage deliberate conservation efforts, particularly the development of management plans that require the restoration of degraded land resulting from mining activities.  相似文献   
247.
The purpose of this study was to investigate the effect of moisture on the heat transfer through clothing in relation to the water vapour resistance, type of underwear, location of the moisture and climate. This forms part of the work performed for work package 2 of the European Union THERMPROTECT project. Thermal manikin results of dry and wet heat loss are presented from different laboratories for a range of 2-layer clothing with similar dry insulations but different water vapour permeabilities and absorptive properties. The results obtained from the different manikins are generally consistent with each other. For each climate, total wet heat loss is predominately dependent on the permeability of the outer layer. At 10 degrees C, the apparent evaporative heat loss is markedly higher than expected from evaporation alone (measured at 34 degrees C), which is attributed to condensation within the clothing and to increased conductivity of the wet clothing layers.  相似文献   
248.
Mayer and Frantz (2004) proposed that their connectedness to nature scale (CNS) provides a measure of people's emotional connection to nature. After reanalyzing data from their article, collecting and analyzing our own data, and conducting a content analysis of CNS scale items, we conclude that the CNS does not measure an emotional connection to nature. Although results from our Study 1 and Study 2 support Mayer and Frantz's conclusion that the CNS measures one predominant factor, we suggest that factor measures cognitive beliefs and not emotional connections. Results from our Studies 3 and 4 suggest that the self-referential, less negatively toned wording of CNS items may account for differences in correlations, between the CNS and environmentalism (a measure of environmental identity) and between the New Ecological Paradigm Scale (a measure of environmental beliefs) and environmentalism, reported by Mayer and Frantz. In Study 5, we suggest that correlation differences reported by Mayer and Frantz may also be attributable to method variance, as opposed to content differences between the CNS and the New Ecological Paradigm scale. We provide recommendations for revising the CNS to focus on beliefs about their connection to nature.  相似文献   
249.
Reactive filter materials used for phosphorus (P) removal from wastewater can be disposed of as soil amendments after treatment, thus recycling P and other macro- and micro-nutrients to plants. In addition, materials with a high pH and Ca content, such as Polonite, are potential soil conditioners, which can be particularly beneficial for acid soils. Polonite previously used for on-site wastewater treatment was applied as a soil amendment to a mountain meadow. The amendment significantly increased soil pH and decreased the hydrolytic acidity, thus reducing Al toxicity risks. The effects were comparable to those of liming. No difference in yield and P uptake by meadow plants was observed. The uptake of metals was lower for amended soils, especially the uptake of Mn. Using Polonite after wastewater treatment as a soil amendment is thus a viable disposal alternative that can replace liming, when necessary, being capable of recycling P and other nutrients to meadow plants.  相似文献   
250.
Source separation sanitation systems have attracted more and more attention recently.However, separate urine collection and treatment could induce odor issues, especially in large scale application. In order to avoid such issues, it is necessary to monitor the odor related compounds that might be generated during urine storage. This study investigated the odorous compounds that emitted from source-separated human urine under different hydrolysis conditions. Batch experiments were conducted to investigate the effect of temperature, stale/fresh urine ratio and urine dilution on odor emissions. It was found that ammonia, dimethyl disulfide, allyl methyl sulfide and 4-heptanone were the main odorous compounds generated from human urine, with headspace concentrations hundreds of times higher than their respective odor thresholds. Furthermore, the high temperature accelerated urine hydrolysis and liquid–gas mass transfer, resulting a remarkable increase of odor emissions from the urine solution. The addition of stale urine enhanced urine hydrolysis and expedited odor emissions. On the contrary, diluted urine emitted less odorous compounds ascribed to reduced concentrations of odorant precursors. In addition,this study quantified the odor emissions and revealed the constraints of urine source separation in real-world applications. To address the odor issue, several control strategies are recommended for odor mitigation or elimination from an engineering perspective.  相似文献   
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