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111.
The aim of the research was to investigate the effects of climate variability on selected water bodies in the Upper East Region of Ghana using time series decomposition and simple linear regression analyses. Data on temperature and rainfall (1960–2015), annual total fish catch (1996–2016), and the recorded water levels (1987–2015) of a major reservoir, the Tono, were used. Time series decomposition analyses were performed on the rainfall, temperature, and water level data to identify their trends. While temperature was increasing, rainfall was decreasing and resulted in a decrease in the water level in the Tono Reservoir. The decreasing water level in the reservoir made fish catch easier, which led to overfishing. Out of the other 39 dugouts studied, 8 (21%) were silted. Also, rainfall was decreasing at 4.4% per decade and minimum and maximum temperatures were increasing at 2.5% and 0.03% per decade, respectively. The minimum, maximum, and mean water levels of the Tono Reservoir were 3.7, 8.0, and 4.9 meters (m), respectively. The water level of the Tono Reservoir was decreasing by ?0.08 m per year. It is concluded that the water level in the Tono Reservoir was continually decreasing as a result of decreasing rainfall and increasing maximum and minimum temperatures. To maintain a much more stable microclimate and decrease the siltation rate of the reservoirs, farmers are advised to stop farming along the banks of water bodies and avoid clearing vegetation. Fishermen are also encouraged to adopt fish farming in enclosed areas within the reservoir to meet the growing protein demands in the Upper East Region of Ghana.  相似文献   
112.
The increasing use of toxic pesticides is a major environmental concern. Carbendazim is a systemic fungicide having wide applications for controlling fungal diseases in agriculture, forestry and veterinary medicines. Carbendazim is a major pollutant detectable in food, soil and water. Carbendazim extensive and repeated use induces acute and delayed toxic effects on humans, invertebrates, aquatic life forms and soil microorganisms. Here, we review the pollution, non-target toxicity and microbial degradation of carbendazim for crop and veterinary purposes. We found that carbendazim causes embryotoxicity, apoptosis, teratogenicity, infertility, hepatocellular dysfunction, endocrine-disrupting effects, disruption of haematological functions, mitotic spindle abnormalities, mutagenic and aneugenic effect. We also found that carbendazim disrupted the microbial community structure in various ecosystems. The detection of carbendazim in soil and reservoir sites is performed by spectroscopic, chromatographic, voltammetric, nanoparticles, carbon electrodes and mass spectrometry. A review of the degradation of carbendazim shows that carbendazim undergoes partial to complete biodegradation in the soil and water by Azospirillum, Aeromonas, Alternaria, Bacillus, Brevibacillus, Nocardioides, Pseudomonas, Ralstonia, Rhodococcus, Sphingomonas, Streptomyces and Trichoderma.  相似文献   
113.
Journal of Material Cycles and Waste Management - The accumulation of floatable litter load captured in gross pollutant trap (GPT) due to the hydrological runoff has become challenging due to rapid...  相似文献   
114.
Environmental Geochemistry and Health - Micronutrients deficiency in soil–plant and human is well-addressed; however, little is known about their spatial distribution, magnitude of deficiency...  相似文献   
115.
Environmental Science and Pollution Research - Climate change is occurring and is influencing biological systems through augmented temperatures, more inconstant precipitation, and rising CO2 in the...  相似文献   
116.
Environmental Science and Pollution Research - This study assessed the economic value of public urban green spaces (UGSs) in Kuala Lumpur (KL) city by using the hedonic price method (HPM). It...  相似文献   
117.
A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide–tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time decreases with the increase of the initial carbon dioxide pressure up to 2.96 MPa. Beyond this pressure, the induction time is becoming relatively constant with the increase of initial carbon dioxide pressure indicating that the liquid phase is completely supersaturated with carbon dioxide. Experimental results show that the inclusion of tetrahydrofuran reduces the induction time required for hydrate formation. These observations indicate hydrate nucleation process and onset growth are more readily to occur in the presence of tetrahydrofuran. In contrast, the presence of sodium chloride prolongs the induction time due to clustering of water molecules with the ions and the salting-out effects. It is also shown that the degree of subcooling required for hydrate formation is affected by the presence of tetrahydrofuran and sodium chloride in the hydrate forming system. The presence of tetrahydrofuran in the hydrate system significantly reduces the amount of carbon dioxide uptake. The apparent rate constant, k, for those systems are reported.  相似文献   
118.
A new mathematical model has been developed that expresses the toxicities (EC50 values) of a wide variety of ionic liquids (ILs) towards the freshwater flea Daphnia magna by means of a quantitative structure-activity relationship (QSAR). The data were analyzed using summed contributions from the cations, their alkyl substituents and anions. The model employed multiple linear regression analysis with polynomial model using the MATLAB software. The model predicted IL toxicities with R2 = 0.974 and standard error of estimate of 0.028. This model affords a practical, cost-effective and convenient alternative to experimental ecotoxicological assessment of many ILs.  相似文献   
119.
In this study, effect of fibre surface treatment on tensile, flexural and chemical resistance properties were studied for sisal fibre reinforced composites. Natural ligno cellulosic sisal fibre reinforced composites were prepared by different surface treatments by hand lay-up method. Fibre surface treatments were carried out to produce good interface between the fibre and the matrix to improve the mechanical properties. Fibre surface treatments were done by boiled the sisal fibres in different % of NaOH and treated the fibres in different % of NaOH, treated in acetic acid and methanol. Unsaturated polyester resin was used as the matrix for preparing the composites. For comparison, these properties for untreated sisal fibre reinforced composites were also studied. From the results it was observed that 18% aqueous NaOH boiled sisal fibre reinforced composites have higher tensile, flexural properties than other composites. Untreated sisal fibre composites show lower properties than treated composites. Chemical resistance properties indicate that all sisal fibre reinforced composites are resistance to all chemicals except carbon tetra chloride. The tests are carried out as per the ASTM standards.  相似文献   
120.
This study investigates the environmental Kuznets curve (EKC) hypothesis in 10 of the Organization of Petroleum Exporting Countries (OPEC). To realize the study’s aims a time series model is built based on the period 1977–2008, utilizing the ecological footprint as an environmental indicator and income, labour, capital, oil consumption and oil price as economic indicators. Employing the Autoregressive Distributed Lag (ARDL) approach, by comparing the short and long-run income elasticities, the EKC hypothesis is present in six OPEC countries namely Algeria, Iraq, Venezuela, Nigeria, Qatar and Kuwait. Moreover, the Toda–Yamamoto–Dolado–Lütkepohl (TYDL) causality tests outcome show that, after oil consumption, the most significant factors in increasing ecological footprint are labor and capital. This implies the relocation of pollution intensive industries to almost all of the OPEC countries. However, oil prices reduce environmental damage by its negative effect on the ecological footprint. From the outcome of this study it is important for the investigated countries to reduce their consumption of fossil fuel energy since it represents an important source of pollution. This can be achieved by allocating more labor and capital in projects and investments on renewable energy, energy efficiency and energy saving.  相似文献   
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