The Open Environmental Engineering Journal最新文献

{"title":"Modelling of Non-Point Source Pollution Around Lake Victoria Using SWAT Model: A Case of Simiyu Catchment Tanzania","authors":"R. Kimwaga, D. Mashauri, F. Bukirwa, N. Banadda, U. Wali, I. Nhapi, I. Nansubuga","doi":"10.2174/1874829501104010112","DOIUrl":"https://doi.org/10.2174/1874829501104010112","url":null,"abstract":"Pollutant loading in Lake Victoria is resulting from a wide range of anthropogenic activities. This study fo- cused on Non-Point Sources (NPS) of pollution and it was carried out to identify and characterize land-use activities and to quantify the sediment and nutrient loads (nitrogen and phosphorus). The study was conducted in Simiyu catchment of Lake Victoria using land-use data of 1975 and 2006 and comparing the relative impact of land-use change on sediment and nutrient load (P and N) into the lake. Possible best management practices were also identified for those sub-basins with the highest pollution yield. Remote sensing using the package ILIWIS 3.0 was used to identify and characterize the land-use and the Soil and Water Assessment Tool (SWAT) model was used to quantify sediment and nutrient load from these two different land-use scenarios. Land use classification according to the SWAT model shows that Agricultural Land-Generic (AGRL) contributes about 73.43%, Range-brush (RNGB) contributes 24.42%, Pasture (PAST), 2.10% Sa- vanna (SAVA) 0.03% and Water (WATR) 0.02% of the total catchment area of Simiyu. It was also found out that there was an expansion of agricultural land from covering 19.33% of the catchment to 73.43% at an annual change rate of 2.9%. However, average Nitrate load was higher for 1975 than 2006. The P load of 1975 was less compared to that in 2006. Model simulation at the catchment outlet for N gave 77.2 kg/km 2 .yr while observed values were 146 kg/km 2 .yr, simulated P was 47 kg/km 2 .yr while observed was 164 kg/km 2 .yr. Hence, the model underestimated nutrient yield in the catchment. Therefore, the applicability of the SWAT modelling tool in studying NPS pollution yields poor model per- formance due to the scantiness of data used for model calibration. More rigorous data campaigns have to be carried out along the two rivers of Duma and Simiyu for purposes of gaining enough information for model calibration and valida- tion. With good model performance, developing management plans to control NPS pollution around Lake Victoria could be achieved using the SWAT model.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126944794","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":"Greywater Reuse And Recycling Potential: The Case Of Mwanza City","authors":"Esnati Osinde Chaggu","doi":"10.2174/1874829501104010078","DOIUrl":"https://doi.org/10.2174/1874829501104010078","url":null,"abstract":"Greywater is wastewater emanating from domestic activities such as laundry, dishwashing, and bathing. This water can have useful on-site uses like irrigating landscape and vegetables in tower gardens. However, its user potential need to include quality studies for determining its safety and achieving public health and environmental protection. Lake Victoria receives greywater from Mwanza City environs and therefore, protecting it from greywater pollution is very important. This research work with study components including socio-economic and the quality of greywater is adding to the need of protecting the lake from pollution. The results, Faecal Coliforms values ranging from 12 to too numerous to count (count/100 ml.) and Total coliforms values of 17 to too numerous to count (count/100 ml.) are clearly showing that, the greywater available in Mwanza is not safe. Moreover, it is evident from the heavy metals' results from liquid samples that, the values are insignificantly very low (<0.01 mg/L for Pb and Cu). The pH values are ranging from 5.9 to 7.5 while the recommended World Health Organisation (WHO) range is 6.76 - 8.0. The research is proposing tower gardens as treatment facility for greywater in Mwanza City.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"387 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134326211","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":"Modeling Diffusive Flux of Non Point Source Pollutants in Lake Victoria: A Comparison Study of Fick's Law and the Fokker-Planck Law","authors":"N. Banadda, F. Ayaa, I. Nhapi, U. Wali, R. Kimwaga, D. Mashauri","doi":"10.2174/1874829501104010105","DOIUrl":"https://doi.org/10.2174/1874829501104010105","url":null,"abstract":"Mathematical models have the potential to conceptually quantify, link and simulate the interactive processes of nature. In this study 68 samples were collected at Gaba landing site in Uganda during a rainy season and were analyzed for nutrients, namely, Ammonia, Nitrite, Nitrate, and Phosphate. In addition, portable meters were used to measure Total Dissolved Solids (TDS) and Dissolved Oxygen (DO) instantaneously at point of sample collection. Within the lake, sam- ples were taken at for horizontal transects of 10 metres (m) interval over a distance of 50 m from the shore where surface runoff was released. At each 10 m sampling point, three samples were drawn at vertical distances of 0.5 m, 1.0 m and 1.5 m from water surface using a hand pump with graduated delivery pipe. This paper presents the results obtained from the application of two alternative expressions, fick's law and Fokker-Planck law to gain insight into the pollutants diffusive flux patterns within the lake. We conclude that in general the Fokker-Planck model should be given preference, in model- ling Ammonia and Phosphate flux profiles while Fickian model should be deployed in modelling DO, TDS, Nitrites and Nitrates.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129522514","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":"Characterization of Brewery Wastewater for Reuse in Kigali, Rwanda","authors":"Nakure Nyilimbabazi, N. Banadda, I. Nhapi, U. Wali","doi":"10.2174/1874829501104010089","DOIUrl":"https://doi.org/10.2174/1874829501104010089","url":null,"abstract":"Like many developing countries, Rwanda is grappling with water shortages in the face of both increased urbanization and industrialization. Other options that will provide water for industrial activities without necessarily tapping into new water sources must be explored. This study investigates the prospects of wastewater re-use using a case study of Bralirwa soft drink factory (BSDF) in Kigali City, Rwanda. From August 2009 to January 2010, laboratory experiments were conducted at both Bralirwa wastewater treatment plant laboratory and National University of Rwanda water laboratory. The main objective was to characterize wastewater from BBSDF so as to determine its reuse options. The parameters analyzed included Temperature (T), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Turbidity, Ammonium Nitrogen (NH4-N), Total Nitrogen (TN), Total Phosphorus (TP), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Electro-Conductivity (EC), Salinity, equivalent OH- and Residual Chloride. The Bralirwa soft drink factory wastewater removal efficiencies for TSS, BOD5, EC, TDS, NH4N, TP, Residual Chloride, and equivalent OH-, was 72%; 93%; 30%; 25%; 78%; 30%; 84% and 92%, respectively. Based on recommended Rwandan wastewater quality re-use standards, this study concluded that Bralirwa wastewater re-use options are lawn irrigation, agricultural irrigation, factory reuse etc.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"11 8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125739449","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":"Assessing the Challenge of Settlement in Budalangi and Yala Swamp Area in Western Kenya Using Landsat Satellite Imagery","authors":"S. Onywere, Z. Getenga, S. Mwakalila, C. Twesigye, J. K. Nakiranda","doi":"10.2174/1874829501104010097","DOIUrl":"https://doi.org/10.2174/1874829501104010097","url":null,"abstract":"The Budalangi area of Kenya exhibits high levels of rural poverty despite its natural resources potential and favourable climate. The area was mapped using multi-temporal remote sensing image data from 1973 to 2009 and participatory data collection. Floods are a recurrent environmental hazard and impede access to environmental resources and agricultural production. The physical setting of Budalangi at the floodplain of Nzoia River and increased runoff from degraded catchments are contributory factors to the flooding. Floods lead to disruption of human settlements and destruction of crops, shelter, dykes and infrastructural facilities. Disease outbreaks also increase due to destruction of sanitation facilities and relocation of settlements in makeshift camps. This implies that the policy measures that have been instituted by the government to mitigate the problem have had dismal impact in the Budalangi and Yala Swamp area. The degradation of the catchment is reflected in its sediment loading and deposition into Lake Victoria which has seen the morphology of the coastline at the mouth of Nzoia River and the aerial coverage by water in the lake change over the years. The overall loss in the area under Yala Swamp is 54 Kmfrom 186 Kmin 1973 to 132 Kmin 2009. The encroachment has significant implication on the wellbeing of the Yala Swamp and the Nzoia Floodplain ecosystem. The study therefore underscores the need to evolve an integrated watershed management plan for effective management of Budalangi and Yala Swamp area and the region in general.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128747510","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":"Environmental Quality and Fish Communities in Selected Catchments of Lake Victoria","authors":"F. Muyodi, F. Mwanuzi, Raphael Kapiyo","doi":"10.2174/1874829501104010054","DOIUrl":"https://doi.org/10.2174/1874829501104010054","url":null,"abstract":"Water quality and fish species are studied in selected catchments of Lake Victoria. The major aim of the study is to establish the relationship between the environmental quality and fish communities in the selected study sites of Lake Victoria. Physico-chemical characteristics of water in selected sites were determined on-site while nutrients and heavy metals were determined in the laboratory using standard methods. Fish samples were collected using experimental multi- filament gillnets with varying mesh sizes. Fish identification was done using external morphological characteristics and identification keys. Physico-chemical results in Thruston bay revealed rise in water column temperature and turbidity as compared to those measured by earlier studies on the lake. Dissolved oxygen (DO) ranged from 0.9 mg L -1 in Yala catchment to 11.56 mg L -1 in Thruston bay. Phosphorus (P) ranged from 9.78 � g L -1 to 120.67 � g L -1 in Thruston bay and in Yala catchment, it ranged from 185.2 � g L -1 to 1526.9 � g L -1 . The nitrate-nitrogen loading in the Geita catchment ranged from 130 to 7465 kg N between the years 2006 and 2008. The results in the inshore sites show a potential for higher photosynthetic rates than in the offshore sites implying that there is more food for the fish in the inshore sites than in the offshore sites. Results further reveal that in Thruston bay there are 13 fish species and Haplochromines dominate the fish catch in terms of numbers. Heavy metals including mercury resulting from artisanal and commercial gold mining in the Geita study site were also detected in the discharges into the lake. This paper also presents measures for the sustain- able management of the lake environment, its quality and fisheries.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124302963","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":"Assessment of Water Pollution Levels in the Nyabugogo Catchment, Rwanda","authors":"I. Nhapi, U. Wali, B. K. Uwonkunda, H. Nsengimana, N. Banadda, R. Kimwaga","doi":"10.2174/1874829501104010040","DOIUrl":"https://doi.org/10.2174/1874829501104010040","url":null,"abstract":"This study aims to develop a comprehensive system of pollution monitoring and control in the Nyabugogo catchment of Rwanda, which also includes the capital city, Kigali, through locating and highlighting pollution and its sources. Pollution hotspots were identified, covering areas of both anthropogenic and natural pollution. The study focused on water quality assessment especially the identification of the critical points of pollution (hotspots), by measuring selected physico-chemical parameters in the Nyabugogo River system. An extensive monthly water quality monitoring study was conducted from October 2008 to May 2009 and covered nutrients, organic and heavy metal pollutants. The parameters covered are Ammonium-Nitrogen (NH4 + -N), Nitric-Nitrogen (NO2 — N), Nitrate-Nitrogen (NO3 — N), Sulphates (SO4), Phosphates (PO4-P), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Dissolved Oxygen (DO), Total Dissolved Solids (TDS), Chromium (Cr), Iron (Fe), Lead (Pb), Manganese (Mn), Zinc (Zn), Conductivity (EC), pH, and Turbidity. The samples were collected, preserved and analyzed in the laboratory using standard methods whilst TDS, conductivity, turbidity and pH were measured in the field using HACH field kits. The water quality study revealed that both urbanized and rural sub-catchments have serious but different types of pollution. For example, the water from rural areas is heavily contaminated with nutrients, suspended sediments (due to a lot of erosion upstream) and organic materials whilst from urban areas the predominant pollutants are heavy metals and some nutrients. It was therefore concluded that the Nyabugogo River system is very heavily polluted and urgent action to control both rural and urban pollution is required. Further studies are required to isolate and quantify the sources of this pollution.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116958672","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":"The Impact of Land Use Activities on Vegetation Cover and Water Quality in the Lake Victoria Watershed","authors":"C. Twesigye, S. Onywere, Z. Getenga, S. S. Mwakalila, J. K. Nakiranda","doi":"10.2174/1874829501104010066","DOIUrl":"https://doi.org/10.2174/1874829501104010066","url":null,"abstract":"The impact of land use activities on loss of vegetation cover and water quality was assessed in three selected sites within the Lake Victoria Basin using remote sensing technologies and standard water quality analysis techniques. The three study sites were: (i) Nzoia River Basin (Kenya), (ii) Nakivubo Wetland (Uganda) and (iii) Simiyu drainage basin (Tanzania). Lake Victoria is the second largest fresh water lake in the world and is served by a drainage basin area of over 193,000 km 2 , traversing five East African Community States; Kenya, Uganda, Tanzania, Rwanda and Burundi. This paper examines the impact of land use activities on vegetation cover and water quality based on remote sensing and Geographical Information Systems analysis combined with chemical and physical water analysis. The quality of the effluent generated by the industries found within the study sites and their effects on downstream discharge was also determined. Pesticide residues in soil and water samples were determined using analytical standard methods. Soils from some selected fields in Nzoia River basin showed high levels of compounds such as aldrin, dieldrin, endosulfan, DDT, and endrin which are together referred to as persistent organic pollutants (POPs). The physical and chemical analysis of water quality revealed high levels of phosphates and nitrates along the agricultural zones of River Nzoia Basin. The satellite images revealed that in all the three study sites land vegetation cover has continuously reduced in size. The extent of environmental degradation caused by agricultural, domestic and industrial wastes and how this affects loss of vegeta- tion cover and water quality is discussed.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127941865","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":"The Potential of a Low Cost Technology for The Greywater Treatment","authors":"F. Kariuki, K. Kotut, Victor G. Nganga","doi":"10.2174/1874829501104010032","DOIUrl":"https://doi.org/10.2174/1874829501104010032","url":null,"abstract":"Greywater (GW) is household wastewater effluent originating from baths, showers, kitchen and hand wash basins and laundry and constitutes 50-80% of indoor household water use. It represents water that can potentially be intercepted at the household level for use. In Kenya, GW use is practiced on an informal basis to supplement irrigation water, either in urban gardens in middle to upper income suburbs or in food gardens in lower income informal, periurban and rural areas. However, the reuse of greywater for irrigation without any significant pre-treatment poses a potential risk to both human and environmental health due to microbial and chemical contamination. This study investigated the potential of a low cost greywater treatment (GWT) system for safe greywater reuse by households. The system comprises of discrete units of barrels that allows for filtration, flocculation, sedimentation and disinfection. GWT system produced water with both pH and electrical conductivity suitable for irrigation according to WHO guidelines. It was also efficient at eliminating Salmonella sp. and reducing total coli form in composite greywater from households in Homa Bay after the effluent was disinfected with commercial disinfectant, sodium hypochlorite (NaOCl). The cleaned greywater had a total coli form count (2.5x10 6 cfu/100 ml) comparable to 0->2.4 � 10 6 cfu/100 ml obtained when greywater was treated using an expensive biological aerated filter (BAF). Fecal coli form counts (2.1� 10 2 cfu/100 ml) compare well with 10 3 cfu/100 ml provided in WHO guidelines for public parks and crops likely to be eaten uncooked. The treatment had no effect on dissolved oxygen, pH, salinity and electrical conductivity. The study concludes that the GWT system can be a sustainable and promising low cost low technology treatment system that can be run and maintained by unskilled operators.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114414364","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":"Applicability of Engineered Wetland Systems for Wastewater Treatment in Tanzania – A Review","authors":"S. Mbuligwe, M. Kaseva, G. Kassenga","doi":"10.2174/1874829501104010018","DOIUrl":"https://doi.org/10.2174/1874829501104010018","url":null,"abstract":"In the literature on treatment wetlands, a technology that is fast gaining popularity in Tanzania as well as else- where in the world, there are misconceptions and missing background links which do not auger well for the development and dissemination of the technology. The misconceptions and missing links pertain to the background, types and classifi- cation, treatment mechanisms, and applicability of the technology. These deficiencies constitute the premise of this paper. The paper outlines the background of engineered wetland systems (EWSs) starting with natural treatment systems as a whole, expounding on the reversible transformations between wetlands and aquatic as well as land treatment systems. It particularly dwells on the background, classification, components, functions, treatment mechanisms, and performance as well as applicability of EWSs. Notably, the paper encompasses a discussion on mechanisms that affect pollutants removal in non - conventional EWSs like those employed in environmental remediation of contaminated sites. The paper also pro- files treatment performance efficiency data for some existing EWSs. Furthermore, it discusses the applicability of the technology in Tanzania.","PeriodicalId":344616,"journal":{"name":"The Open Environmental Engineering Journal","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115477733","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}