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Livestock Browsing Threatens the Survival of Balanites aegyptiaca Seedlings and Saplings in Dinder Biosphere Reserve, Sudan
Get PDFThis research article published by Taylor & Francis Online, 2021While the impact of livestock grazing has been frequently assessed for grasses, little is known about how livestock affects tree seedlings and saplings. We explored the effects of goat, cattle and camel browsing on the survival of Balanites aegyptiaca seedlings and saplings, a broadleaved evergreen tree species indigenous to Sudan, in Dinder Biosphere Reserve-Sudan (DBR). We used a stratified sampling design with four sites: GOA (mainly browsed by goats), CAT and CAM being mainly browsed by cattle and camels, respectively, while CON was a control area without any livestock browsing. We tested the survival, mortality and recovery of seedlings and saplings across different sites. Our results revealed that mortalities of seedlings in GOA were almost four times higher than that of CAM and CON and twice that of CAT (F3,196 = 100.39, P < .001). Further, sapling mortality was three times higher in GOA than that observed in CAT and CON (F3,196 = 73.4, P < .001). We found that seedlings recover better than saplings, and, unexpectedly, goat browsing severely affected the natural regeneration of B. aegyptiaca in DBR compared to other livestock species. Our study findings contribute to sustainable forest management and show that particularly goat browsing needs to be suppressed for conservation of vulnerable tree species
Coastal upwelling and seasonal variation in phytoplankton biomass in the Pemba Channel
Get PDFThis research article published by African Journals Online, 2021This study was conducted in the Pemba Channel off Tanga Region in northern Tanzania to investigate physical and
chemical factors that drive changes in phytoplankton biomass. Three transects off Mwaboza, Vyeru and Sahare were
selected. For each transect, ten stations were sampled. Phytoplankton biomass was determined as chlorophyll-a
(Chl-a) concentration. Similarly, physico-chemical variables (temperature, salinity, dissolved oxygen, pH and nutrients) were determined. It was observed that the Chl-a concentration was significantly higher during the northeast
monsoon (median 1.44 mg m-3) as compared to the southeast monsoon (median 1.19 mg m-3; W = 2216, p = 0.029).
The higher productivity during the northeast monsoon is attributed to the presence of high-nutrient water caused
by coastal upwelling. It is concluded that indication of upwelling, observed through relatively low temperatures
during the northeast monsoon season, could be responsible for bringing nutrient-rich waters to the surface, which
in turn stimulated the increase in Chl-a concentration
Health Risk Assessment of Trace Elements in Soil for People Living and Working in a Mining Area
Get PDFThis research article published by Hindawi, 2021The present study used soils collected from a small-scale gold mine area to determine the health risks due to trace elements to the at-risk population in the study area. The work involved 74 soil samples from four sampling categories: 29 samples were from the mining pits (MD), 18 samples from the first washing area (WA), 17 samples from the second washing area (WB), and 10 samples from the control area (C). All samples were analyzed for Cr, Cu, As, Pb, Cd, Co, Ni, Zn, and Hg using the Energy Dispersive X-Ray Florescence (ED-XRF) method. Trace element levels were found to vary across the four sampling categories. The concentrations of trace elements recorded from different sampling categories varied in an increasing order of MD > WA > WB > C. Mercury was detected in the highest levels (max. 3.72 ± 0.15) at WB while it was not detected in the samples from C. Samples from MD indicated that Cu (max. 737.66 ± 1.3 mg/kg) was found in the highest levels whereas Hg (mean = 0.007 mg/kg) was the lowest. At WA, Cu (max. = 178.97 ± 2.46 mg/kg) registered the highest average concentration while Hg (mean = 0.05 mg/kg) had the lowest concentration. For WB, Cu (max. = 230.66 ± 3.99 mg/kg) was found in the highest concentration. The hazard index value for all exposure routes was found to be 1.77, making noncarcinogenic effects significant to the adult population. For children, the hazard index value was 9.11, showing a severe noncarcinogenic effect on children living in the study area. For the noncancer effects through the inhalation pathway, the risk posed by Ni, Cu, Zn, and Pb was negligible for both adults and children, while Co posed the highest noncancer risk for children. Cobalt also indicated the highest noncancer risk for children through the dermal pathway, while As indicated the highest noncancer risk to children through ingestion. For the cancer risk, the adults were more at risk compared to children, except for As and Co through the dermal pathway posing the highest threat. Trace element concentrations, hazard quotient, and hazard index values indicated that the area was polluted and that noncarcinogenic and carcinogenic effects on residents and miners were significant. Therefore, there is a need to put in place mining regulations aimed at protecting the at-risk human population in the study area
Effect of bat guano and rabbit urine liquid fertilizers on growth physiognomies of Spinacia oleracea under hydroponics
Get PDFThis research article published by Current Horticulture, 2021, Volume : 9, Issue : 2This pilot research study assessed the effect of bat guano and rabbit urine as organic nutrient sources for growing Spinacia oleracea (spinach) under a non-circulating hydroponic system. Three treatments; bat guano (5 g/L of water), rabbit urine (50 ml/L of water) and a commercial hydroponic fertilizer as the positive control were tested. Three-week-old spinach seedlings were transplanted into a small net cup fitted on a 4-litre bucket. Data collected on plant height, root length and number of leaves was analyzed using Origin Pro software. Single factor ANOVA results showed no significant difference in the height of spinach grown using bat guano, rabbit urine and commercial hydroponic fertilizer solutions (P<0.05). A significant difference was observed on the length of the root and number of leaves among the three hydroponic solutions (P<0.05). Results showed that both bat guano and rabbit urine have the potential to be used in hydroponic spinach production
Challenges facing community health workers in promoting maternal and neonatal health in Bagamoyo and Mkuranga districts, Tanzania
Get PDFThis research article was published by African Journals OnLine, 2021Objectives: Community health workers (CHWs) play significant roles in areas where professional health workforce
succumb to serious human resource deficiencies. This study explored challenges the CHWs face in promoting ma ternal and neonatal health in two districts of Tanzania.
Design: A cross-sectional study design was conducted in Bagamoyo and Mkuranga districts from March to May
2019.
Methods: Qualitative data were collected using in-depth interviews from 30 CHWs, thematic analysis was carried
out by identifying major key themes emerging from the data.
Results: The study found little community support resulted from jealousy of male household heads, mistrust, social cultural believes and lack of community appreciation on the role of CHWs. Little support from local government
resulted by political grievances among local leaders due to change in political administration. Other challenges were
lack of basic knowledge in maternal and neonatal health, including breastfeeding. Irregular working schedules due
to poor supervision, huge workload, old age and tiredness
Conclusion: CHWs programs in Bagamoyo and Mkuranga districts were inactive and required innovative strategies
to raise community and local government cooperation. Jealousy among male household’s heads and CHWs need
community members to participate in establishment of selection criteria. Socio-cultural beliefs call for community
sensitization on how they affect maternal and neonatal health. Lack of community appreciation on the role of
CHWs, irregular working schedule implied poor supervision and defined age limit would overcome challenges re lated to old age
Regeneration and carboxymethylation of cellulose and its derivatives: application assessment for brewery wastewater treatment
Get PDFThis research article published by Springer Nature Switzerland AG., 2021Coagulation–flocculation technique is usually employed in wastewater treatment by applying conventional inorganic materials such as alum and ferric chloride. Due cost to environmental challenges associated with the use of inorganic flocculants, biopolymers are gaining ground as alternative water treatment materials. In the present study, native cellulose and hemicelluloses isolated from sugarcane bagasse were used in the removal of turbidity and biological oxygen demand from industrial wastewater. Isolated native cellulose was modified to form regenerated cellulose (RC). Also, native cellulose, hemicellulose and RC were carboxymethylated using Na-chloroacetate. Thereafter, the functional groups on the carboxymethylated biopolymers were examined using Fourier transform infrared spectroscopy and the carbon–hydrogen–nitrogen–sulfur–oxygen elemental analysis. The degree of substitution (DS) for regenerated and carboxymethylated cellulosic materials was measured using recommended standard methods. Carboxymethyl cellulose (CMC) with 1.3 DS reduced turbidity and biological oxygen demand by 62.2 and 64%, respectively. Carboxymethyl regenerated cellulose (CMC-II) at 1.1 DS reduced turbidity and by 55.6 and 60%, respectively. Carboxymethyl hemicellulose (CMH) with 1.4 DS was capable of reducing turbidity and biological oxygen demand by 45.7 and 47%, respectively. Carboxymethyl cellulose and hemicellulose have rarely been used in the treatment of brewery wastewater. In the present study, these two novel materials showed a good prospect in removing biological oxygen demand and turbidity
Life cycle analysis of potential municipal solid wastes management scenarios in Tanzania: the case of Arusha City
Get PDFThis research article published by Springer Nature, 2021The municipal solid wastes (MSW) management technologies in most cities of developing countries pose a continuous risk of contaminating the environment and affecting human health adversely; often because MSW technologies are not comprehensively analyzed before their implementation. For this purpose, the life cycle assessment methodology was applied to access the different MSW management scenarios in Arusha City, Tanzania. Three different scenarios of recycling and sanitary landfilling (RSL) were developed as the business as usual scenario (RSL) (SN-1), RSL combined with composting (SN-2), and RSL combined with anaerobic digestion (SN-3). Results obtained showed that no scenario performed better in all impact categories, however with the current focus on climate change and limited funds in developing countries, the best option would be SN-2. The SN-2 which is the combination of recycling, composting and the landfill had the least economic cost and environmental burdens in most categories when compared to the other scenarios. The sensitivity analysis results indicated that improving diesel consumptions, reducing methane emissions to air and increasing the recycling rate of papers and plastics would reduce the total environmental impacts on all scenarios
Changing Patterns and Drivers of Increased Pesticides Use in Smallholder Vegetable Production Systems in Tanzania
Get PDFThis research article published BioRxiv, 2021Pesticides use has become a key component of smallholder horticulture production. Therefore, dynamics in pesticides handling need to be ascertained. This study assessed drivers of pesticides use and determinants of changing patterns of pesticides handling practices in smallholder vegetable systems. Data were collected from 385 farmers from Iringa, Arusha, Manyara, and Kilimanjaro regions in Tanzania through an in-depth survey and field observations. A binary probit model was used to derive factors fostering increased pesticides use. Results showed that 47.9 % of all pesticides were wrongly used. Most farmers (88.6%) lacked knowledge of pest control and 88.9% were unaware of safety practices. Disposal methods of empty pesticides foster occupational and environmental exposure (58%). There was an increasing trend in pesticides use (58.4%), accompanied by changing pesticides formulations. Over 60 pesticides with 29 different formulations were used. Mixing pesticides (71.2%), high dose rates with increased frequency of application were observed. Pesticides under Class II WHO hazard (68.9%) dominated. Extremely hazardous (Class Ia) and highly hazardous (Class Ib) were also used. Binary probit model showed that number of crops grown, pesticides mixing, and region contributed positively to the likelihood of increased pesticides use while farmers’ perception of effectiveness of pesticides, lack of access to safe use information, poor use of safety gears and inability to read pesticides labels had a negative impact. The fate of pesticides use in smallholder vegetable production systems is therefore the culmination of serious health and environmental implications. Excessive pesticides use escalated by increased number of crops, improper use of PPE, and pesticides mixing practices subjects the general population to pesticides environmental exposure thereby jeopardizing sustainability of smallholder vegetable production in Tanzania. Regular training to farmers and extension officers on current and emerging issues on pests and pesticide safe use is vital
Mathematical models for the dynamics of alcohol related health risks with changing behavior via cultural beliefs in Tanzania
Get PDFThis research article published by Communications in Mathematical Biology and Neuroscience, 2021Alcoholism has continually posed health challenges in many communities for decades. In this paper, a more realistic model for health related risks associated with alcoholism is formulated. It considers a population proportion that has social cultural protection from alcohol consumption. In the context of this paper, such protection emanates from religious beliefs. The Next Generation Matrix (NGM) approach is used to compute the basic risk reproduction number. The risk free equilibrium point is proved to be globally asymptotically stable whenever the basic risk reproduction is less than unity and unstable otherwise. The sensitivity analysis of the basic risk reproduction number and numerical simulation results reveal that for effective control of the health risk problem in the community, the deliberate intervention strategies and policies should focus on discouraging alcoholic behaviors on its onset during initiation stage than focusing other population proportions already at risk
Influence of land use change on nitrate sources and pollutant enrichment in surface and groundwater of a growing urban area in Tanzania
Get PDFThis research article published by Springer Nature Switzerland AG., 2021In the present study, 3-year (1997, 2008 and 2017) satellite images as well as different hydro-chemical parameters, nitrogen and oxygen isotopic composition of nitrate were used to examine the impacts of land use and land cover change on surface and groundwater quality. Through isotopic composition, sources of surface and groundwater pollutants were also elucidated. The results showed significant land use transition whereby land use changed from forest and bare land to agricultural land and built-up areas. A slight reduction in the size of areas covered by water bodies was also observed. Results indicate differences in nitrate concentration that mirror land use changes. Samples with elevated levels of nitrate above 10 mg/L were located near agricultural fields and areas with intensive livestock keeping activities. In groundwater, ẟ15N-nitrate and ẟ18O-nitrate ranged from 3.2‰ to 20.1‰ with a mean value of 11.7 ± 1.8‰ and from 2.1‰ to 12.0‰ with mean value of 5.4 ± 1.8‰, respectively. In surface water, ẟ15N-nitrate and ẟ18O-nitrate ranged from 2.4‰ to 19.3‰ with mean value of 4.9 ± 1.4‰ and from 1.5‰ to 21.9‰ with a mean value of 13.5 ± 2.8‰, respectively. Isotopic composition data suggest sources of nitrate in both ground and surface water dominated by synthetic and organic fertilizer application and to a lesser extent a natural soil nitrate source