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611.
Coal combustion by-products such as fly ash (FA), brine and CO(2) from coal fired power plants have the potential to impact negatively on the environment. FA and brine can contaminate the soil, surface and ground water through leaching of toxic elements present in their matrices while CO(2) has been identified as a green house gas that contributes significantly towards the global warming effect. Reaction of CO(2) with FA/brine slurry can potentially provide a viable route for CO(2) sequestration via formation of mineral carbonates. Fractionated FA has varying amounts of CaO which not only increases the brine pH but can also be converted into an environmentally benign calcite. Carbonation efficiency of fractionated and brine impacted FA was investigated in this study. Controlled carbonation reactions were carried out in a reactor set-up to evaluate the effect of fractionation on the carbonation efficiency of FA. Chemical and mineralogical characteristics of fresh and carbonated ash were evaluated using XRF, SEM, and XRD. Brine effluents were characterized using ICP-MS and IC. A factorial experimental approach was employed in testing the variables. The 20-150 μm size fraction was observed to have the highest CO(2) sequestration potential of 71.84 kg of CO(2) per ton of FA while the >150 μm particles had the lowest potential of 36.47 kg of CO(2) per ton of FA. Carbonation using brine resulted in higher degree of calcite formation compared to the ultra-pure water carbonated residues. 相似文献
612.
Geographic variation in the population dynamics of a species can result from regional variability in climate and how it affects reproduction and survival. Identifying such effects for migratory birds requires the integration of population models with knowledge of migratory connectivity between breeding and nonbreeding areas. We used Bayesian hierarchical models with 26 years of Breeding Bird Survey data (1982-2007) to investigate the impacts of breeding- and nonbreeding-season climate on abundance of American Redstarts (Setophaga ruticilla) across the species range. We focused on 15 populations defined by Bird Conservation Regions, and we included variation across routes and observers as well as temporal trends and climate effects. American Redstart populations that breed in eastern North America showed increased abundance following winters with higher plant productivity in the Caribbean where they are expected to overwinter. In contrast, western breeding populations showed little response to conditions in their expected wintering areas in west Mexico, perhaps reflecting lower migratory connectivity or differential effects of winter rainfall on individuals across the species range. Unlike the case with winter climate, we found few effects of temperature prior to arrival in spring (March-April) or during the nesting period (May-June) on abundance the following year. Eight populations showed significant changes in abundance, with the steepest declines in the Atlantic Northern Forest (-3.4%/yr) and the greatest increases in the Prairie Hardwood Transition (4%/yr). This study emphasizes how the effects of climate on populations of migratory birds are context dependent and can vary depending on geographic location and the period of the annual cycle. Such knowledge is essential for predicting regional variation in how populations of a species might vary in their response to climate change. 相似文献
613.
Nicolas Goñi John Logan Haritz Arrizabalaga Marc Jarry Molly Lutcavage 《Marine Biology》2011,158(5):1057-1073
This study aims to describe the variability of albacore (Thunnus alalunga) diet in the Northeast Atlantic and Mediterranean Sea and to identify possible relationships between this variability and
the features of different feeding areas, the behavior, and the energetic needs of albacore. Stomach contents from albacore
caught in five zones of the Bay of Biscay and surrounding waters (n = 654) and three zones of the Mediterranean Sea (n = 152) were analyzed in terms of diet composition and stomach fullness. Carbon and nitrogen stable isotope and C/N ratios
were measured for white muscle and liver from albacore in the Bay of Biscay (n = 41) and Mediterranean Sea (n = 60). Our results showed a spatial, seasonal, inter-annual, and size-related variability in the diet of albacore. Albacore
diet varied by location in the Mediterranean Sea, with a particularly high proportion of cephalopods, and low δ15N values in the Tyrrhenian Sea. In the Northeast Atlantic, albacore consumed a higher proportion of crustaceans and a lower
proportion of fishes in the most offshore sampling zone than inshore. The digestion states of the major prey reflected a diurnal
feeding activity, indicative of feeding in deeper waters offshore, whereas on the continental slope, feeding probably occurred
in surface waters at night. Important seasonal and inter-annual diet variability was observed in the southeast of the Bay
of Biscay, where preferred albacore prey appeared to be anchovy (Engraulis encrasicolus). Stomach fullness was inversely related to body size, probably reflecting higher energetic needs for smaller individuals.
Albacore from the Bay of Biscay had significantly lower δ13C and higher δ15N values compared with albacore from the Mediterranean Sea, indicative of regional baseline shifts, and trophic position and
muscle lipid stores in albacore increased with body size. 相似文献
614.
Ako AA Shimada J Hosono T Ichiyanagi K Nkeng GE Fantong WY Eyong GE Roger NN 《Environmental geochemistry and health》2011,33(6):559-575
Groundwater quality of the Banana Plain (Mbanga, Njombe, Penja—Cameroon) was assessed for its suitability for drinking, domestic,
and agricultural uses. A total of 67 groundwater samples were collected from open wells, springs, and boreholes. Samples were
analyzed for physicochemical properties, major ions, and dissolved silica. In 95% of groundwater samples, calcium is the dominant
cation, while sodium dominates in 5% of the samples. Eighty percent of the samples have HCO3 as major anion, and in 20%, NO3 is the major anion. Main water types in the study area are CaHCO3, CaMgHCO3, CaNaHCO3, and CaNaNO3ClHCO3. CO2-driven weathering of silicate minerals followed by cation exchange seemingly controls largely the concentrations of major
ions in the groundwaters of this area. Nitrate, sulfate, and chloride concentrations strongly express the impact of anthropogenic
activities (agriculture and domestic activities) on groundwater quality. Sixty-four percent of the waters have nitrate concentrations
higher than the drinking water limit. Also limiting groundwater use for potable and domestic purposes are contents of Ca2+, Mg2+ and HCO3
− and total hardness (TH) that exceed World Health Organization (WHO) standards. Irrigational suitability of groundwaters in
the study area was also evaluated, and results show that all the samples are fit for irrigation. Groundwater quality in the
Banana Plain is impeded by natural geology and anthropogenic activities, and proper groundwater management strategies are
necessary to protect sustainably this valuable resource. 相似文献
615.
616.
Merrington Graham Peters Adam Wilson Iain Cooper Chris Van Assche Frank Ryan Adam 《Environmental science and pollution research international》2021,28(2):1789-1800
Environmental Science and Pollution Research - National Environmental Quality Standards (EQS) for zinc used for the assessment of ecological status in freshwaters have been shown to vary by over... 相似文献
617.
Venancio Wilson Augusto Lima Rodrigues-Silva Caio Spina Mylena Diniz Vinicius Guimarães José Roberto 《Environmental science and pollution research international》2021,28(19):23742-23752
Environmental Science and Pollution Research - Benzimidazoles (BZ) are among the most used drugs to treat parasitic diseases in both human and veterinary medicine. In this study, solutions... 相似文献
618.
Spina Mylena Venâncio Wilson Rodrigues-Silva Caio Pivetta Rhannanda Copetti Diniz Vinicius Rath Susanne Guimarães José Roberto 《Environmental science and pollution research international》2021,28(19):24034-24045
Environmental Science and Pollution Research - Photoperoxidation (UV/H2O2) was used to degrade three of the worldwide most consumed antidepressant pharmaceuticals—bupropion, escitalopram, and... 相似文献
619.
The proliferation of community-based collaborative approaches to public land management and planning has spawned many questions regarding issues of community representation and the effects of participation for local residents. This paper presents a longitudinal assessment of local resident participation in collaborative forest planning on local community–forest relations in southwestern Colorado. Using survey data of participants involved in the San Juan National Forest's forest plan revision community study groups from 1998 to 2003, we assess participation in terms of community representation and the effects of community-based collaboration upon individuals' forest uses, forest values, and the level and form of involvement in forest management and planning activities. Results show that community representation remains slanted towards existing active stakeholders, and that while forest values, uses, and frequencies of involvement change little, participants cite positive effects in terms of the development of new knowledge, personal relationships, and greater confidence to engage in forest management affairs. 相似文献
620.
No clear ecological footprint calculation strategy is available for small- and mid-sized communities within Canada. By adjusting provincial or national footprint findings using data sets available in the public domain, we develop and test a calculation strategy to estimate municipal ecological footprints. Because the calculation approach is consistent with the Global Footprint Network standardised methodology, it permits meaningful comparisons between communities and with global and national footprint estimates. It offers planners, policy-makers, and community leaders an accessible, straight forward, and cost effective strategy for estimating the ecological footprint at the community and municipal level. The suggested approach is best suited for using the ecological footprint as an awareness and education tool. The large number of limitations associated with calculating the municipal approach and limitations associated with calculating ecological footprints in general at the local level make it an unsuitable tool to inform community planning and policy development. 相似文献