American Journal of Environmental Sciences最新文献

{"title":"Understanding the Relationship between Aquaculture and Poverty: The Case of Gurudaspur, Natore","authors":"Saman Saad, Raisa Bashar, F. Yeasmin, N. Khan","doi":"10.3844/AJESSP.2018.1.11","DOIUrl":"https://doi.org/10.3844/AJESSP.2018.1.11","url":null,"abstract":"Aquaculture is perceived as a source of income and economic raise in several small towns and villages of Bangladesh and Gurudaspur of Natore region is no different. From the 1990s onward it brought about a great economic boost. However, in the last decade and at present, several negative externalities of this practice have started to surface, including severe water-logging (after flooding), depletion of water resources and economic losses. These issues can be attributed to unplanned fish pond-cutting and unrestricted entry into the aquaculture business. Based on this background, this study tried to capture the change in the economic condition of people associated with small-scale aquaculture, through focused group discussions, participatory rural appraisal and individual interviews, with the owners and workers about their past and present incomes, before and after they started fish-farming, in two villages of Gurudaspur, namely Brigarila and Moharajpur. Additionally, basic GIS analysis was performed to analyze the changes in land use patterns and their impacts on the surroundings. The authors’ observations about the present status of the owners of the fish-farms were also noted, along with some recommendations based on the local governments’ advice and initiatives to stop new pond-cutting (which is not seeing much success). There is no doubt that even though aquaculture in Gurudaspur saw a positive inception, its progression was flawed and, consequently, the mentioned problems are becoming bigger as days go by. Although, Moharajpur’s water-logging problem (some of which still exists because much needed canal building is ongoing) is not that severe (due to higher years of experience and hence more development in this sector), Hence, Brigarila’s condition is already very dire and worsening day by day. It is the conclusion of the authors that Gurudaspur’s aquaculture practices are unplanned and hence, unsustainable and will soon not yield any more profits, leaving several hundred in an economic downturn, if proper drainage systems and laws are not implemented, coupled with relevant training and education.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"2 1","pages":"1-11"},"PeriodicalIF":0.0,"publicationDate":"2018-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78041552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Building Resilience in Natural Capital to Reduce Disaster Risks and Adapt to Climate Change: A Case of Wetlands in the Eastern Free State; South Africa","authors":"J. Belle, N. Collins, A. Jordaan","doi":"10.3844/AJESSP.2017.358.377","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.358.377","url":null,"abstract":"Wetlands are a form of natural capital which provide services that improve the welbeing of the local community. Unfortunately many wetlands have been degraded before their values and functions were realised. Using a system thing appraoach and a mixed research method, this article collected primary data from 176 respondents using questionnaires. Besides, 21 wetlands were observed using field observation data sheet while interviews were conducted with 31 environmental, disaster and climate change experts. Lastly secondary data were obtained from the South Africa Weather Service on two climate parameters. All these data were used to investigate the vulnerability and functions of wetlands as a natural capital and how to build wetland resilience in the eastern Free State of South Africa. The main findings were that wetlands especially those in communal land were still very vulnerable partly due to ignorance of wetland values and functions. The dominant function of the wetlands in the study area was agriculture (both crop production and grazing). These wetlands also perform other functions that support the welbeing and safety of the local community. Despites these valuable functions, wetland degradation is still going on and the management is still predominantly reactive. The main recommendation therefore was a proposed integrated management framework that build wetland resilience to the changing environment characterised by increasing extreme weather events and disaster risks exacerbated by negative impacts of climate change.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"4 1","pages":"358-377"},"PeriodicalIF":0.0,"publicationDate":"2017-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78867151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation the Anaerobic Digestion Performance of Organic Waste from a Landfill in Morocco","authors":"Fatima Ebich, R. Ramdan, A. Essamri","doi":"10.3844/AJESSP.2017.351.357","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.351.357","url":null,"abstract":"Organic household waste has a high organic content (69 g/kg), value of pH equal to 6,3 with 94% of moisture. Anaerobic digestion is one of the technologies for recycling and stabilization of organic waste, the process is carried out in 3L reactor at semi continuous and mesophelic conditions. During the anaerobic digestion of OHW, pH was around neutrality (between 6,5 and 8), a decrease of alkalinity was observed reaching a value of 900 mg CaCo3/L), total and volatile solid were accumulated at the end of the experiment. Result of biogas production indicates that a higher methane yield was obtained for the load 0,5 g VS/L, methanogenic potential for the anaerobic digestion of OHW was 0,15LSTP/g VS.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"22 1","pages":"351-357"},"PeriodicalIF":0.0,"publicationDate":"2017-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76513113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Temperature and Precipitation on Global Mangrove Rhizophora Species Distribution","authors":"Aroloye O. Numbere, G. Camilo","doi":"10.3844/AJESSP.2017.342.350","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.342.350","url":null,"abstract":"Climate change influences the distribution of mangroves towards tropical or temperate regions of the world. We hypothesized that Rhizophora species organized along complex spatial and temporal temperature and precipitation gradient. To determine the affinity of different mangroves with climatic parameters, the response of eight Rhizophora species to seven climatic parameters (i.e., annual mean temperature, annual precipitation, maximum temperature of warmest month, minimum temperature of coldest month, temperature annual range and temperature of driest month and precipitation of warmest month) was analyzed with Arc GIS and Maxent software. For temperature and precipitation there was significant difference (p<0.001) among species location. Only R. selala (p<0.001) differed most from the rest taxa in temperature. The jackknife test in Maxent revealed that minimum temperature of coldest month (regularized training gain ~0.71), temperature annual range, (regularized training gain ~0.66) and annual mean temperature (regularized training gain ~0.36) were the most important environmental parameters that determine the occurrence of R. mangle, being the most dominant species. This outcome was further validated by an accuracy of 91%. This implies thattemperature  was a better predictive parameter  than precipitation in the distribution of R. mangle.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"98 1","pages":"342-350"},"PeriodicalIF":0.0,"publicationDate":"2017-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76547264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Seasonal Autoregressive Integrated Moving Average Models for River Flow Forecasting","authors":"K. Tadesse, M. Dinka, T. Alamirew, S. Moges","doi":"10.3844/AJESSP.2017.378.387","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.378.387","url":null,"abstract":"Reservoir operation policies cannot be functional in instant decision making without forecasting the future reservoir inflows. For forecasting inflows into reservoirs with only hydrological data is available like Koga irrigation dam, multivariate forecasting models cannot be used to generate accurate river flow information. As a result, an evaluation of univariate Seasonal Autoregressive Integrated Moving Average (SARIMA) models was done for forecasting monthly Koga River flow with Gnu Regression, Econometrics and Time-series Library (GRETL) software. The stationarity of historical river flow sequence was checked by Augmented Dickey-Fuller (ADF) unit root analysis. Then, seasonality was removed from the river flow time series by seasonal differencing. Using seasonally differenced correlogram characteristics various SARIMA models were identified and evaluated, their parameters were optimized and diagnostic checks of forecasts were performed using residual correlograms and Ljung-Box tests. Finally, based on minimum Akaike Information criteria, SARIMA (1, 0, 1) (3, 1, 3)12 model was selected for Koga River flow forecasting. The stationarity test of the forecasted values of this model has proved the similarity of forecast values and patterns with those of the historical ones. Thus, irrigation managers could use this model and forecast information for optimal irrigation planning and development of reservoir operation strategies in order to protect farmers and downstream environment from water shortages. Moreover, the use of stationarity test of forecast flow patterns is useful and applicable in selecting best forecast model during forecasting of any river flows.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"29 1","pages":"378-387"},"PeriodicalIF":0.0,"publicationDate":"2017-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83618097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Different Environments on Reinforcement Concrete Corrosion","authors":"Mohammed Awwad, O. Ahmad","doi":"10.3844/AJESSP.2017.307.314","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.307.314","url":null,"abstract":"This research focuses on various forms of steel bar corrosion located in different environments and the factors affecting the corrosion process, both the external (surrounding environment around concrete elements) and the internal environment (concrete itself), as well as on the investigations and tests for this type of damage, in order to develop measurements and recommendations that will reduce harmful investment as much as possible, by increasing the durability and resistance to aggressive environments throughout their life span.The results showed that the concentration (100%-75%) of sulfuric acid decreases more in steel bars diameter than in the second week, but the difference is negligible, and there is no change in the color of precipitation. Concentration (50%-25%) of sulfuric acid also showed decreases in bars diameter than in the second week, but the difference could be omitted, except for the concentration (50%) of sulfuric acid white layer appearance on the steel. In the fourth week, in NAOH, there has been no obvious change in the diameter of steel and an increase was noticed in the deposits substance as well as the appearance of external rust of Steel. HNO3 with a 25% concentration continued a dramatic corrosion of steel and a large decrease in the diameter of steel was observed, which led to a change in the color of the liquid to brown, due to the fragmentation of steel, and the corrosion of the non- soaked steel. When exposing the reinforcing bars for acid and base at different concentrations to investigate the ultimate tensile stress, a high decrease in the tensile strength of the steel bar was found, due to the concentration of nitric acid (25-50%) compared to the other acids and base, and this decrease is caused by a high degree of corrosion.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"119 12 1","pages":"307-314"},"PeriodicalIF":0.0,"publicationDate":"2017-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84036772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lead Phytotoxicity Induced Changes in Biochemical Markers in Germination and Seedlings in Durum Wheat Triticum durum Desf. Cv.Vitron and Gta","authors":"S. Slimani, M. Boudelaa, Saddek Abdelmadjid, A. Ladjama, Imène Nedjah, M. Benkaddour","doi":"10.3844/ajessp.2017.334.341","DOIUrl":"https://doi.org/10.3844/ajessp.2017.334.341","url":null,"abstract":"Among the heavy metals most commonly found on land, lead is a strongly represented pollutant in soil and sediments. It is easily absorbed and accumulated in different parts of plants. On the macroscopic scale, lead causes unfavorable effects on plants. First and in the event of excess, it may exert toxicity affecting several stages of germination development in leaf formation and root elongation in the early stages of development. The effect of lead on two varieties of durum wheat Triticum durum cv Gta and Vitron have been analyzed on germination under laboratory conditions. The objective is to determine the influence of lead on (i) germinal parameters and (ii) the stress physiological markers. The experiment was set up in a completely randomized design with 3 replications of 20 seeds per variety, including 4 concentrations of Pb(NO3)2 (0, 320, 430 and 660 ppm) on the germination. Average ambient temperature was 22°C, the humidity was 32% and photoperiod light/dark was 16/8 h. The obtained results showed a real sensitivity of germination to lead. Indeed, it was noted a total absence of germination of the two varieties in all seeds treated with the highest concentration. The treatment of seeds by the increasing doses of lead decreased the germinative faculty considerably, the content of pigments and disrupted the cellular metabolism, the proteins, the proline and glutathione levels. These results indicated that lead stress caused a decrease in germinal parameters and significant impairment of cell biochemical markers. Such effect was inversely proportional to the doses used. It was also noted that the Gta variety was less sensitive to lead toxicity than Vitron.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"126 1","pages":"334-341"},"PeriodicalIF":0.0,"publicationDate":"2017-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79805590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vermicompost Incorporation into Soil Contaminated with Deltamethrin as an Attempt to Reduce the Toxicity Caused by this Pyrethroid: A Structural Study of Soil","authors":"Fernanda Benetti, L. B. F. Pigatin, M. M. Kanashiro, R. N. Rodrigues, M. O. Rezende","doi":"10.3844/AJESSP.2017.297.306","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.297.306","url":null,"abstract":"The use of vermicompost for remediating soil contaminated with the commercial formulation containing deltamethrin was proposed. Biotoxicity tests with the goal of evaluating the potential remediation degree of the vermicompost after its addition to contaminated soils were performed. The tests lasted 56 days and involved Eisenia foetida earthworms. Possible structural changes in humic acids from these soils were evaluated by means of FTIR spectroscopy. The soil contaminated with deltamethrin offers toxicity to the earthworms. However, the vermicompost addition caused great positive impact on soil contamination level, which became quite similar to the reference soil. The vermicompost remedial effect depends on the source material. In this study the vermicompost were from filter cake and orange peel. The results obtained by FTIR pointed out for a weak interaction such as van der Waals type between the pyretroid and humic acids.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"74 1","pages":"297-306"},"PeriodicalIF":0.0,"publicationDate":"2017-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73140214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Studies on Proximate Composition and Phytochemical Screening of Mango, Key lime, African star apple and African pear Seeds as Possible Coagulant Aids for Water Treatment","authors":"A. Seghosime, J. Awudza, R. Buamah, Sampson Oduro Kwarteng","doi":"10.3844/AJESSP.2017.325.333","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.325.333","url":null,"abstract":"Many fruits including mango (Mangifera indica), key lime (Citrus aurantiifolia), African star apple (Chrysophyllum albidum) and African or bush pear (Dacryodes edulis) are nutritionally valuable as human food, however after consumption of the fruits, their seeds are discarded as wastes since they are of no commercial value and this results in disposal problems. Hence assessment of the constituents of such waste seeds will enable their application to be considered. In this study the proximate composition and phytochemical constituents of the seeds of Duncan mango (Mangifera indica), key lime (Citrus aurantiifolia), African star apple (Chrysophyllum albidum: C. acreanum) and African or bush pear (Dacryodes edulis: D.e.var.edulis) obtained from southern part of Nigeria have been investigated and compared for the four different seeds. The results obtained from the proximate analyses showed that the major constituent of the seeds are carbohydrates, proteins and fats. The key lime seed was found to contain more protein and fat compared to the other seeds while the African star apple seed was found to contain the least fat and more carbohydrate compared to the other seeds. The phytochemicals detected in all the seeds were tannins, glycoside, coumarins and phenols, however steroids were absent. Only African star apple seed contained saponins and alkaloids. The results further indicated that only the key lime seed was devoid of flavonoid and starch. Tannins in plants have been reported to be among the active agents that bring about coagulation and natural polymers (proteins, carbohydrate (starch) etc.) act as bridging flocculants. Saponins, flavonoids coumarins and phenols have also been reported to posses antibacterial potentials against pathogenic organisms. This study shows that these seeds contain these constituents and they are present in reasonable amount. Therefore it is concluded that these seeds can be investigated as possible coagulant aids for drinking water treatment.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"13 1","pages":"325-333"},"PeriodicalIF":0.0,"publicationDate":"2017-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81858701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reassessment of Molecular Variation in Isolated Populations of Deschampsia cespitosa from Metal Contaminated Regions in Northern Ontario (Canada) after 17 Years of Potential Genetic Recombination","authors":"S. Rainville, P. Beckett, K. Nkongolo","doi":"10.3844/AJESSP.2017.289.296","DOIUrl":"https://doi.org/10.3844/AJESSP.2017.289.296","url":null,"abstract":"The effects of ore extraction and processing procedures in the Greater Sudbury and Cobalt regions have been long-lasting. The objective of this study is to determine the current level of genetic variation in Deschampsia cespitosa populations from metal contaminated and uncontaminated sites in samples collected in Northern Ontario in 2016 after 17 years of potential genetic recombination since the last study in 1999. D. cespitosa leaf samples collected from the City of Greater Sudbury (CGS), Cobalt and Little Current were analyzed using ISSR primers. The levels of genetic variation were moderate to high within targeted populations. There was no significant difference (p≤0.05) in the overall percent of polymorphic loci in metal-uncontaminated site of Little Current (from 70% in 1999 to 77% in 2016) and in a Cobalt Cart Lake site (from 48% in 1999 to 55% in 2016). But a significant decrease in genetic variation was observed in CGS Wahnapitae site (from 72% in 1999 to 54% in 2016). On the other hand, a significant increase was observed in Cobalt Nipissing (from 46% in 1999 to 64% in 2016). The Kelly Lake site in the CGS with the lowest level of polymorphic loci (42.5%) in 2016 was not surveyed in 1999. The degree of genetic relatedness among sites has increased since the populations are more genetically closely related than 17 years ago. No population-specific ISSR marker was identified. The clustering of Cobalt and Sudbury populations strengthens the earlier theory that Sudbury populations of D. cespitosa might be from the Cobalt region.","PeriodicalId":7487,"journal":{"name":"American Journal of Environmental Sciences","volume":"403 1","pages":"289-296"},"PeriodicalIF":0.0,"publicationDate":"2017-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79746405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}