Articles, Conference and Workshop Papers Collection

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Klerksdorp Tornado on March 4, 2007, in South Africa: a synoptic overview
(World Scientific Publishing Company., 2024-06-22) Kimambo, Offoro Neema
This research delves into the factors contributing to tornado formation in South Africa, with a specific focus on the Klerksdorp tornado that occurred on March 4, 2007, in Northwest Province. Despite their recurrent occurrence and significant potential for damage, tornadoes have received relatively little attention. Between 1990 and 2014, these weather phenomena incurred estimated costs exceeding half a billion American dollars in addition to other weather-related disasters. In this study, data from multiple observation systems, including the National Oceanic and Atmospheric Administration (NOAA), the National Centers for Environmental Prediction (NCEP), the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) in Germany, and the South African Weather Service (SAWS), were thoroughly analyzed. The findings reveal that the Klerksdorp tor- nado was linked to a cold front and a cut-off low, which were the dominant weather systems on the day of the tornado. This case study enhances our comprehension of tornado dynamics in South Africa, aiding in improving short-term forecasts and potentially early warning systems. Future research should concentrate on the recurring nature of tornadoes in association with tropical weather systems and locally-driven factors.
Ethnobotanical study of medicinal plants used to manage HIV/AIDS opportunistic infections in Rungwe, Mbeya region, Tanzania
(Academic Journal, 2018) Kibonde, Suma F.; Augustino, Suzana; Mabiki, Faith P.; Mdegela, Robinson
The current ethnobotanical study identified medicinal plant species used to manage HIV/AIDS opportunistic infections by the communities in Rungwe District, Tanzania. Data were collected using questionnaires (n=193), interviews (n=9) and field observations. A total of 31 plant species from 23 families are used in managing HIV/AIDS opportunistic infections. Compositae and Rosaceae were predominantly used in disease management by 15% each. Of the plant parts, leaves were the most used (44%), followed by roots (28%), bark (7%), fruits, seeds and stem (5%) while the least used plant parts were tubers (4%) and the whole (2%). Tuberculosis utilized 60% of the species, Herpes simplex 55%, chronic diarrhea 40%, oral candidiasis 35% and Herpes zoster 30%. Dissotis phaeotricha scored the highest fidelity value (73%), followed by Berberis holstii (60%). The knowledge on medicinal plants among respondents was influenced by; informal education (p<0.01), village location (p<0.01) and ethnic background (p<0.05). The study exposed the presence of reasonable knowledge of traditional medicinal plants among communities in Rungwe District. The results contribute to the conservation of experimental experiential knowledge of medicinal plants used in the management of HIV/AIDS opportunistic infections hence, shouldering world’s efforts geared towards anti-HIV/AIDS innovations.
Urban climate and bioclimate of Dar es Salaam, Tanzania – preliminary results
(Meteorological Institute, Albert-Ludwigs University Freiburg, Freiburg im Breisgau, Germany, 2012) Ndetto, Emmanuel L; Matzarakis, Andreas
Understanding of the urban climate of a city is important for future planning and human wellbeing. The well known Physiologically Equivalent Temperature (PET) and the Universal Thermal Climate Index (UTCI) indices were calculated with RayMan model using meteorological data (2001-2011) in order to study the human thermal bioclimate of Dar es Salaam. Results indicate that afternoons from late September to May is the heat stressful period. On the other hand, the June-August period is relatively a comfortable time of the year especially the morning hours. These results are however treated as preliminary to the detailed and reliable study that uses hourly datasets and of a long duration.
Response of gstase and L iver esterase in goldf ish (Ca rra sius aura tus) and topmouth gudegon (Pseudora sboraparva ) after sublethal exposure to cyhalofop-butyl and profur ite-am in ium
(Chinese journal of pesicide science, 2002) ZHU, Guo-nian; Hui ming, WU; Mwalilino, Jilisa K.; Shao-nan, L I
Investigations w ere carried to assess the sublethal effects of a herbicide clincher ( 100 EC) containing cyhalofop2butyl [ 100 g (a. i) ·L - 1 ] as the active ingredient and the insecticide p rofurite2am inium [ 78% SP, 780 g (a. i) ·kg - 1 ] on liver esterases and hepatic glutath ione2S 2transferase (GST ) in go ldfish (Carassius au ratus) and topmouth gudgeon (P seud orasbora p arva). GST w as found to be induced in bo th go ldfish and topmouth gudgeon by the p rofurite2am inium at concentration of 0. 234 m g·L - 1 . Clincher bo th at concentration of 1 and 2 m g·L - 1 caused GST induction in topmouth gudgeon. The m ixture of clincher and p rofurite2am inium had the h ighest effect in topmouth gudgeon 722. 3 nmo l· (m in - 1·m g - 1 p ro tein ) w ith a po ssible indication of additive toxicity. L iver esterases w ere induced by bo th clincher (1 and 2m g·L - 1 ) and p rofurite2am inium (0. 117 and 0. 234m g·L - 1 ) in go ldfish. In topmouth gudgeon liver esterases w ere induced by p rofurite2am inium but inh ibited by clincher. It is suggested that the two bio transfo rm ation enzym es m ay be directly o r indirectly affected by the tested chem icals and that there are differences betw een them
A radiological risk Assessment of 226Ra, 228Ra and 40K isotopes in tilapia fish and its granitic environment in Singida municipality, Tanzania
(MDPI, 2023) Kazoka, Amin R; Mwalilino, Jilisa; Mtoni, Paul
: Consumption of fish containing elevated levels of radionuclides can lead to undesirable health effects for consumers. People in the Singida Municipality harvest fish from lakes and ponds of granite rocks which are linked with hazardous radioisotopes that may be bio-concentrated by fishes they consume. Currently, no study has ascertained the levels of radioisotopes in fish from these environments. This study was carried out to analyse the radioactivity levels of 226Ra, 228Ra and 40K isotopes in order to assess the radiological risk associated with Tilapia fish consumption and its environment in Singida Municipality. Some 51 samples, which included water (20), sediment (20), Nile tilapia (8) and Manyara tilapia (3), were randomly sampled and composited; then, they were analysed using a high-purity germanium (HPGe) detector, between May and June 2022. The results revealed that (i) the activity levels of 228Ra were below the detection limit for fish and water samples, while in sediment, the combined activity of 228Ra was within the acceptable international levels; (ii) the mean activity concentrations of 226Ra and 40K in all other samples were within the recommended levels; (iii) the activities of radionuclides in the samples analysed were high in sediments, followed by fish, and lastly water; (iv) the bioaccumulation results show that only 40K was bio-accumulated (with 1.26 in Nile tilapia), while other radionuclides (226Ra, 228Ra) were not bio-accumulated; (vi) the radionuclide transfer from water to fish was higher compared to the radionuclide transfer from sediment to fish; (vii) the human effective doses due to consumption of Nile tilapia and Manyara tilapia were 0.00973 and 0.005 mSv/y, respectively, which is below the 1 mSv/y international limit. These findings therefore show that the current levels of radioactivity in fish in the study area do not pose a significant radiological risk to fish consumers. However, more studies on other types of fish are recommended.
Health risks assessment for paddy rice farmers during rice crop production in Eastern Tanzania
(Journal of Entomology and Zoology Studies, 2020) Mwalilino, JK; Kyando, I; Kilonzo, BS; Mnyone, LL; Mulungu, LS
The study was conducted to assess health risks of paddy rice farmers using agrochemicals in System Rice Intensification (SRI) and non SRI farms in Mkindo and Hembeti villages in Mvomero District, Eastern Tanzania. Structured questionnaires and face to face interviews were used for data collection. The majority of paddy rice farmers in the study villages (96.67% and 86.6% of respondents in Hembeti and Mkindo respectively) confirmed using agrochemicals in their paddy fields. Generally, the use of agrochemicals was higher in non SRI than in SRI farms. Most of agrochemicals used in these study villages were found to be in class II hazard with moderate effects on both human and environment health. The storage and disposal systems of pesticide containers in the study villages were observed to be reasonably good and hence risks of pesticides poisoning and contamination of soil and water sources were considered to be limited. It was further noted that most paddy rice farmers do not use complete person protective equipment (PPE) probably due to poverty and limited knowledge on the importance of such equipment in protecting themselves against effects of pesticides on health. Furthermore, the study revealed that there was substantial shortage of extension officers who could educate the paddy rice farmers and agrochemicals shop sellers on the health effects of pesticides used in rice production. On the basis of the findings in the current study, increasing farmer’s awareness and training aimed at equipping farmers with knowledge on sustainable agriculture, agrochemicals uses and integrated pest management, so as to lower the potential health effects of such chemicals, is recommended.
Analytical methods for Cyhalofop-butyl and its metabolites in Soil and water
(China academic journal electronic publishing house, 2001) Mwalilino, Jilisa K; L i, Zhao; Guonian, Zhu; Yingxu, Chen
A relatively simp le and less expensive m ethod is p ropo sed fo r the determ ination of cyhalofop2butyl (XDE2537) and its m etabo lites: R2(+ ) 222[ 42(22fluo ro242 cyanophenoxy) phenoxy ] p ropano ic acid (AC ID ); R2(+ ) 222[42 (42 carboxyl222fluo ro242 cyanophenoxy) phenoxy ] p ropano ic acid ( D IAC ID ); and 22[42(42carbamoyl222 fluo rophenoxy) phenoxy ] p ropano ic acid (AM IDE). Conversion of the parent compound to its arylöalkylöo r halide derivative fo r determ ination by GC w as found unnecessary. O nly HPLC w as used and under gradient elution all the four compounds separated w ell. Good recoveries w ere obtained w ith the fo rtified so il and w ater samp les. Low pH w as impo rtant fo r the extraction of the four components
Accumulation of SOC in relatively undisturbed tropical mountain foothills under climate change scenarios: the case of Uluguru mountain, Tanzania
(Saudi Society for Geosciences and Springer Nature Switzerland AG, 2023-07-01) Mkonda, Msafiri Y.; Minja, Gileard S.; Ligate, Elly J.; Kaganga, Laison S.; Haule, Tiemo R.; Msemwa, Ubaya S.
Soil nutrients form an important part of agro-ecosystems in various landscapes, including mountainous areas. Most foothills in tropical mountains are heterogeneous in terms of the accumulation of soil nutrients due climatic location and ecological endowments. Since most mountain foothills have potential for the provision of environmental services, it is imperative to assess the salient soil nutrients including carbon in order to determine the amount. This study assessed the accumulation of soil organic carbon (SOC) in the relatively undisturbed foothills of Uluguru Mountains whose geology indicates that they were formed during cretaceous age (i.e. ≈50 million years ago). The study also determined the trends of rainfall and temperature because these elements of climate have important influence on carbon accumulation. In conducting this study, we sampled Kiroka Village (in Kiroka Ward) because it is found at the foothills of the Uluguru Mountain and most of its parts are relatively undisturbed. In this place, sixteen soil sampling points were established within one hectare and these points involved two soil depths (i.e. 0-20 cm and 20-40 cm) and two locations (i.e. lowland and upland). The Walkley–Black Method was used for SOC analysis while Mann–Kendall Test was employed for climate data analysis. The results exhibit that there have been significant variations in SOC accumulation under the two soil depths and locations. In the lowland areas, SOC was 1.1 and 0.43 MgC ha −1 for the depths 0–20 cm and 20–40, respectively. Besides, in upland areas, SOC was 0.38 and 0.31 MgC ha −1 for the depths 0–20 cm and 20–40, respectively. Most cereal crops require a considerable amount of SOC in the soil that ranges between 0.5 and 2 MgC ha −1 . Additionally, the mean annual rainfall and temperature patterns from 1980 to 2020 declined and intensified at R2 = 0.15 and 0.19, respectively. Therefore, these results inform environmental experts, climate practitioners and other relevant stakeholders to endorse suitable and sustainable environmental management methods in the mountainous areas.
Stakeholders’ engagement in the process of adapting to climate change impacts: a case of central Tanzania
(Emerald Publishing Limited, 2022-02-13) Mkonda, Msafiri Yusuph
Purpose – It is imperative to intensively engage stakeholders in the process of adapting to climate change impacts because stakeholders are important components in adaptation process and policy formulation. However, there is slight empirical evidence that has been established to indicate whether the stakeholders are significantly involved in developing various adaptations plans. Design/methodology/approach – As a way of bridging that gap, this study adopted both primary and secondary data and assumed various techniques. In-depth, semi-structured interview was the major approach and most interviews were conducted between June and August 2020. Here, 20 stakeholders were involved in this kind of participatory process. To make results more rigorous, the data from interviews were enriched with data from documentary reviews. Generally, the data were analyzed through theme content analysis. Findings – The results exhibit that there has been little engagement of stakeholders in undertaking various researches especially in marginalized areas. In some instances, several stakeholders have been included; however, the most important ones have been excluded in the process, thus affecting the provision of data. The inconsistences affect the whole adaptation process and bring numerous controversies with the existing realities which recognize stakeholders as important entity in the adaptation process. Subsequently, this has widely affected even the set ups of decision-making organs and the policy formulation processes at large. Originality/value – Explicitly, the results of this study are essential to climate scientists and practitioners, as the results reveal the real situation in the field. Similarly, the results inform how various sustainable projects, plans and policies related to climate change adaptations can be developed. Conclusions are therefore drawn to strengthen sustainable adaptation to climate change impacts through increased stakeholder involvement.
Socio-economic and ecological benefits of forest reserves in Tanzania, a case of Nambinga forest in Ulanga district
(Allerton Press, Inc., 2022-03-22) Ngwembe, J. F.; Minja, G. S.; Tegeje, A. J.; Mkonda, M. Y.
Forest reserves have numerous advantages ranging from economic to ecological in various areas of the globe. Recently, there have been increased anthropogenic activities in the forest reserves for subsistence, commercial and ecological purposes. These activities are mainly done around the forest reserves as livelihood options. The present paper aims at (i) assessing the perception of the local population living near the forest reserves on the values of forest, (ii) assessing the anthropogenic activities done in the forest, (iii) examining the temporal changes of the forest, and (iv) investigating the social, economic and ecological benefits of the forest resources. Although this paper applied mixed approaches in data collection; it mostly applied household survey, key informant interview, and snow bowling approaches. Quantitative data were mainly analyzed through SPSS version 22, while qualitative data were analyzed through theme content analysis. The results exhibit that; more that 70% of the respondents are aware of the actual and potential resources of the forest, while more than 50 are harnessing the resources (e.g. firewood, charcoal, and medicines). In addition, the forests have numerous economic and ecological benefits including increased income and infrastructure. However, deforestation and impacts of climate change are some of the major challenges affecting the forest reserves. The findings of this study would provide useful information about benefits of anthropogenic activities on the forest and these findings would be made available to development planners of various ministries of various countries including Tanzania.
Robust variation in the potentials of Tanzanian soils under sisal plantation to stabilize organic carbon and nitrogen: a case of Handeni district
(Journal of Geography & Natural Disasters, 2023-03-21) Mkonda, Msafiri Yusuph
Understanding the impacts of tillage erosion on Soil Organic Carbon (SOC) and Nitrogen (N) fractions is essential for targeted soil conservation in cropland areas. SOC and N play significant role in the global Carbon (C) and N cycles. Establishing SOC and N stock is a good step towards implementing the “4 per 1000” (4p1000) initiative which was launched at the COP21 conference in Paris aiming to slow down the rising levels of atmospheric carbon dioxide (CO 2 ). Thus, it is essential to understand how much SOC and N are stored in the soil and if possible to determine how long these nutrients persist belowground. Previous studies indicate that the storage of SOC and N strongly affected the interaction of climate and minerals. However, most of these results have not consistently considered the cropland soils (sisal plantation) as specific ecosystem. In attempting this study, we sampled the sisal plantation of Handeni District because the area partly represents the grassland of Tanzania. Sixteen soil sampling points were established within ten hectares and they involved two soil depths (i.e. 0-20 cm and 20-40 cm) and two locations (lowland and upland). The results exhibit that there have been significant variations of SOC and N accumulations under the two soil depths and locations. In the lowland areas, SOC was 1.3 and 0.45 MgC ha −1 for the depths 0–20 cm and 20-40 cm, respectively. Besides, in upland areas, SOC was 0.60 and 0.34 MgC ha −1 for the depths 0–20 cm and 20-40 cm, respectively. Similarly, the total N was significantly higher 2.12 Mg (0-20cm) in lowland than in upland 1.80 Mg (0-20 cm). The same pattern happened in the depth (20-40 cm) where lowland had 1.40 Mg and upland had 1.16 Mg. These insights in cropland soils allow us to infer that the alterations of SOC and N are significantly influenced by climate change and minerals. Biologically, the microbial activity and microbial biomass correlate with SOC and N. This means, different agro-ecological zones of the country can have different SOC and N storages.
The influence of soil organic carbon and climate variability on crop yields in Kongwa district, Tanzania
(Springer, 2022-01-07) Mkonda, Msafiri Y.; He, Xinhua
This study assessed the influence of soil organic carbon (SOC) accumulation and climate variability on crop yields in Kongwa District, central Tanzania. In doing so, climate data and soil samples were collected from Mnyakongo and Ugogoni villages through soil sampling, interviews and surveys. Walkley–Black method, Mann–Kendall test, and MS Excel were used to analyze SOC, climate, crop yields respectively. The results exhibited that the accumulation of SOC was significantly greater in soils under organic fertilization (1.15 and 0.80 MgC ha −1 at soil 0–20 cm and 20–30 cm depth) than under no- fertilization (0.35 and 0.30 MgC ha −1 at 0–20 cm and 20–30 cm) and decreased with increasing soil depths. Under these two soil treatments, the average yields for maize, sorghum and millet were almost 1.8 tn ha −1 under organic fertilization and 0.6 tn ha −1 under no-fertilization. Specifically, maize yields ranged from 1.5 to 2.2 tn ha −1 , while both sorghum and millet had 1.1–1.7 tn ha −1 . Therefore, yields were significantly higher under organic fertilizations than under no-fertilizations. Besides, the mean annual rainfall or temperature (1980‒2020) fluctuated at a decreasing (R 2 = 0.21) or an increasing trend (R 2 = 0.30). Comparatively, the yields for maize, sorghum or millet fluctuated at a decreasing trend at R 2 = 0.07, 0.05, or 0.85, respectively. Correspondingly, it was found that the temporal increase in rainfall and temperature had positive (R 2~0.5) and negative (R 2 ~0.3) correlations with crop yields, respectively. In contrast, the decline in rain’s intensity and frequency had negative impacts on crop yields. Thus, both SOC and climate correlated with crop yields.
The underway to pragmatic implementations of sustainable and intensive agricultural systems in Tanzania
(Elsevier, 2021-05-06) Mkonda, Msafiri Yusuph
For the past five decades, Tanzanian has regarded agriculture as a lead sector to economic development. However, more than 70% of the agricultural production has been for subsistence due to weak economic and technological investments. This happens despite the establishment of numerous programs, plans and initiatives to limit the problem. Therefore, there is an increased need to assess some important aspects of agro-ecosystems such as climate, soil and crops as significant factors for determining yields potentials in Tanzania. This approach is particularly important in the fifth term of Tanzanian government (2015–2025) which devotes serious efforts to transform the country to a middle income economy by 2025, whereas, industrial sector will be the key engine to capture this objective. In doing so, crop and climate data were collected from the Ministry of Agriculture and Tanzania Meteorological Agency. Microsoft excel and Theme content were the major methods for data analyses. Although there has been a slight increase in land expansion for crop production, the results exhibit that the overall agricultural trend (tn/ha) has been fluctuating at a declining trend. This yield decline has been significantly caused by rainfall climate change and soil infertility. This scenario is evidenced by the fact that the maximum potential photosynthetic yields in the study area is around 3–5 Mg/ha while that of the developed countries is 160 Mg/ha (10 − 6 Mg/g). Therefore, stoichiometric of fertilizer, rain water harvest or/and artificial rainfall, exploitation of ground water for irrigation, proper mapping or review of soil characteristics based on agro-ecological zones, proper breeding of various crops, intensive investments of finance and technology in agriculture should be adopted to maximize yields in the country.
Awareness and adaptations to climate change among the rural farmers in different agro-ecological zones of Tanzania
(Emerald Publishing Limited, 2022-04-18) Mkonda, Msafiri Yusuph
Purpose – This paper generally aimed to evaluate the knowledge of rural farmers towards climate change (CC) and their adaptation practices as a way of reducing the vulnerability in different agro-ecological zones (AEZs) of Tanzania. This establishment is quite important because rural farmers are most vulnerable to impacts of CC. Therefore, there is a need to establish the actual knowledge on this aspect in order to meet the urgency for action on CC by using the endowed environmental resources. This knowledge will assist policy makers and CC practitioners. Design/methodology/approach – This study employed systematic and simple random sampling procedures in selecting the districts and villages as study sites. It used both quantitative and qualitative data sets derived from climatic records, questionnaires survey, interviews and discussion. The Mann-Kendall test and Sen’s slope, and theme content were used for data analyses. Findings – The results exhibited that most farmers have been greatly adapting to CC through numerous and well-known practices. However, there has been adoption of other new practices mainly influenced by new knowledge from extension services, environmental endowments and temporal environmental change. Although there has been varied perceptions on CC, the results indicate that most farmers (>70%) are aware of the changing climate and their knowledge corresponds to meteorological data. Originality/value – Most farmers perceived that prolonged drought and erratic rains are the main indicators of CC. These indicators were the base of copping and adaptation mechanisms. Despite this, there is a need for all climate practitioners to join hands in improving the existing adaptation practices that can limit climate impacts in local areas.
Agricultural sustainability and food security in agroecological zones of Tanzania
(Springer Nature Switzerland AG, 2021) Mkonda, Msafiri Yusuph
Agricultural sustainability is crucial for developing countries, including Tanzania whose economy and food security entirely depend on agriculture. Tanzania has seven agro-ecological zones with different potentials and challenges to attain agricultural sustainability. These agro-ecological zones are coastal, arid, semi-arid, plateau, southern and western highlands, northern highlands, and alluvial. To attain agricultural sustainability and food security in the country, it is essential to explore biophysical, economic and social dimensions. This chapter reviews the climatic situation, agricultural potentials and agronomic practices. Arid and semi-arid zones are more vulnerable to environmental stress, especially climate change, than plateau, alluvial, and northern and southern highlands. Efficient agricultural sustainability has increased peoples’ income and food security in resilient agro-ecological zones by 50%, and by 10% in vulnerable zones. This has eventually improved the livelihoods of the people in resilient agro-ecological zones, and has allowed cultivation of few crop varieties such as sorghum and millet in vulnerable zones. Areas with the best agronomic practices such as animal manure fertilization have increased crop yields from 0.75 to 1.95 tons ha −1 . As a result, this yield increment has improved the livelihoods of about 70% of Tanzanian farmers who entirely depend in agriculture.
Sustainable management of wetlands in East Africa: a case of Akagera wetland in the north-western Tanzania
(Elsevier, 2022-10-25) Mkonda, Msafiri Yusuph
Although numerous studies have established some pertinent approaches for sustainable management of wetlands in Tanzania, it has been difficult to succeed. Akagera is among the most potential trans-boundary wetland ecosystems in east Africa. However, the wetland is exposed to vast challenges that hinder its sustainability. This study aims to establish the reasons for why it has been difficult to achieve sustainable management of natural resources. This establishment is quite important because wetlands serve the community livelihoods and envi ronmental conservation. To execute such objective, important resources found in the area, their socio-economic potentials, current management situation, and challenges hampering their sustainability have been adequately established. Key informant interviews (especially from elders and experts), and theme content analysis were the major methods for data collection and analysis, respectively. The study exhibits that the Akagera wetland has various biophysical resources such as rivers, national parks, fertile soils and forests, just to mention a few, and these resources are major sources of livelihoods. Despite of that, financial constraint, poaching, deforestation, climate change impacts, encroachment to wetland and national parks, cultural barriers, political instability, and uncoordinated wildlife policies among the east African countries are some of the serious challenges that impede the sustainability of the wetland. Most of these challenges bring tensions and debates on how to intervene issues surrounding wetland management in east Africa and African continent at large. Therefore, it is important to address these challenges to ensure sustainable management of available environmental resources. This study proposes a management approach that is multi-stakeholder and involves communities as applied in China, North America, South Africa, and other Mediterranean countries where the management of wetlands has been more pronounced and proactive.
Hydrochemical characteristics of groundwater and its suitability for drinking and irrigation uses in makutupora sub-basin, Tanzania
(AIP Publishing, 2023-01-10) Mjemah, Ibrahimu Chikira; Mariki, Eliapenda Elisante
The focus of this study was to assess the suitability of groundwater for drinking and irrigation uses in Dodoma Municipality. Hydrochemical investigations was conducted in Dodoma urban where twenty water samples were collected from boreholes/wells to monitor physico-chemical quality. Groundwater samples were measured for pH, Chloride, Nitrate, Electric Conductivity, Total Dissolved Solids and Temperature in situ while major ions (Na + , Ca 2+ , K + , Mg 2+ , NO 3- , Cl - , SO4 2- and HCO 3- ) were analyzed in the laboratory. It was found that the physico-chemical properties of the groundwater varies from fresh to brackish and it is slightly acidic to alkaline. The Na + and Mg 2+ were dominant cations while Cl − and HCO 3− were dominant anions. Furthermore, the results show that for most groundwater quality parameters in Dodoma Municipality are suitable for drinking and irrigation uses. As for Chloride, the average concentration of about 1568.21mg/l seems to be unpalatable for drinking. However, for the Chloride which was found at a range of 710-960mg/l in few boreholes can be used for grapes irrigation, the main crop in the area, and 180-600 mg/l that was found in only one borehole is suitable for stone fruits irrigation. The Nitrate concentration complies with the Tanzania Bureau of Standards (TBS) and the World Health Organisation (WHO) limits for drinking purposes since its concentration was below 50 mg/l. Several groundwater management strategies and recommendations were proposed to control the quality of the groundwater and to get rid of groundwater problems. Furthermore, the study recommends frequent groundwater quality monitoring and integration of groundwater into the water resources management for the benefit of all of Dodoma Municipal people
Impacts of climate variability and hydrological modifications on cyanobacteria potentials in aquaculture systems in the ngerengere catchment, Morogoro, Tanzania
(University of Venda, 2021-04) Kimambo, Offoro Neema
The scientific consensus is that the global increase in cyanobacterial harmful algal blooms (CyanoHABs) is attributed to eutrophication, hydrological variations, and anthropogenic activities compounded by climate change. Cyanobacteria are known to produce a wide range of toxins (cyanotoxins) and hypoxia conditions that can alter the food web. Besides the fact that Tanzania is rich in water resources such as the ocean, lakes, rivers, dams, and ponds and shreds of evidence of environmental constraints, climate and hydrological variations (episodic events and altered river flows), on HABs, much is yet to be done. Their growth is not spatially homogenous, and that there is an information gap on their dynamics. CyanoHABs have registered impacts on food security, tourism, water resources, fishery, and human health. The only recorded incidences (recurrence) are the mass fatalities of Lesser flamingo in Lake Manyara, Arusha. Some recent reports, for instance, gauged the rapid growth of the aquaculture sector as a result of livelihood diversification, but the sector is facing management and environmental constraints. Since the aquaculture farms/fishponds are hydrologically connected with the domestic water reservoirs in the Ngerengere catchment, there is a need for a thorough analysis. The study explored the impacts of climate variability and hydrological modification on cyanobacteria potentials in aquaculture systems in the Ngerengere catchment in Morogoro, in the United Republic of Tanzania. In this study, a review of the literature (i.e., historical reconstruction) on CyanoHABs occurrences in Tanzania and their link with climate and hydrological variation was conducted. A stakeholders’ perception and experience (questionnaire, focus group discussions, and key informant interviews) and anecdotal observations were also conducted and examined. Water samples were collected and analyzed for the identification and characterization of common species of cyanobacteria and in-situ measurements of physicochemical characteristics. Also, case studies were also diagnosed to examined how CyanoHABs link with other key environmental observations. The study also involved obtaining online data for chlorophyll-a to analyze their trends and how they are teleconnected with climate and hydrological variation in Mindu, Dam situated in the Ngerengere catchment. The methods and procedures followed in the study are detailed under the specific chapters. The study found that on HABs, the field is still at its nascent stage in Tanzania, and research iiin the field is lagging. Most studies are events driven, for example, post-mortem analysis and that there is no limnological data to perform time series analysis. Regarding the survey on stakeholders’ perception of CyanoHABs in the Ngerengere catchment, 95% of the respondents could recognize blooms as displayed to them, with 70% noting that algal blooms proliferate more during the dry season. On the other hand, respondents were uncertain about any health effects associated with blooms. During the survey, farmers revealed that they sometimes feel itching during and after fishing, which is linked to toxic effects from CyanoHABs. The morphological assessment shows the occurrences of common species of CyanoHABs in the Ngerengere catchment, such as Microcystis, Cylindrospermopsis, Anabaena, Lyngbya, as well as other species such as diatoms and Euglenophytes, which at times might be a nuisance to the environment. It was further observed that colony-forming cyanobacteria dominated the fishponds while filamentous species were dominant in Mindu Dam (a domestic water supply in the catchment). However, the eutrophic state of the sampling points varied from eutrophic to hypereutrophic state for all the sampling schedules. Moreover, Mindu Dam was eutrophic, becoming hypereutrophic toward the end of sampling (September 2018, usually the dry season). During the study period, two unique cases, namely, heavy rainfall, which caused flash flood (in this study defined as an episodic hydrological event) and unusual observation of reddish colouration (red algae) fishponds at Kingolwira National Fish Farming Centre were gauged and examined. The heavy rainfall event happened between the first (October 2017) and the second (February 2018) sampling phases, which showed to be affecting the equivalent spherical diameter (ESD) and area-based diameter (ABD) of the community structure. The heavy rain phenomenon was localized (enhanced by the orographic nature of the place) but also steered by the presence of the Intertropical Convergence Zone (ITCZ) and the tropical cyclone Berguitta (which was the dominant weather over the Indian Ocean). Regarding the unusual observation of reddish bloom in the fishpond, the associated physicochemical characteristics during the event were also studied. To the best of our knowledge, the observed red algae is the first to be reported in fishponds in Tanzania. These results show that the fishponds were significantly (p<0.05) different from each other except for water temperatures. Microcystis and euglenophytes species respectively dominated non-reddish and reddish fishponds. The study findings demonstrate the dynamics of harmful cyanobacterial blooms in iiithe study area. The use of case studies and observations synergistically can be utilized in understanding the local context hence studying the dynamics of CyanoHABs. A retrospective analysis of chlorophyll-a was conducted in Mindu Dam, which demonstrated increasing Chlorophyll-a trends (defined as a chlorophyll-a index and a ratio between bands characteristics using Landsat 7 surface reflectances), minimum and maximum temperatures, and solar radiation. While rainfall trends were neutral, wind speed and directions and water levels for the Mindu Dam showed a significant decreasing trend with time. However, there was a strong correlation between wind speed and maximum temperature but weak with minimum temperature. There was also a significant weak correlation between Nino-3.4 monthly rainfall as well as water levels. The study area is to the leeward side of the Uluguru mountains. The patterns suggest links and causality between the CyanoHABs variations and meteorological parameters such as temperatures, solar radiations, and water levels. Findings in this study contribute to the understanding of CyanoHABs with climate and hydrological variation in a region in the face of data paucity. The study further provides an insight into state of the art, cause of CyanoHABs, and their link with climate and hydrological variation hence informing policies and practices and professional development. The findings also provide a basis for the development of the CyanoHABs management framework and health risk assessment.
Using land-use change to mitigate impacts of future droughts on water yield in South Africa
(Water Research Commission, 2022-02) Abiodun, Babatunde J.; Naik, Myra; Mogebisa, Tlakale; Makhanya, Nokwethaba; Nguvava, Mariam; Adaramola, Rhoda; Yocgo, Rosita
Conceptualization integrating endemic medicinal plants into the global value chains: the ecological degradation challenges and opportunities
(University of Venda, 2018-11-02) Tom, Volenzo; Odiyo, John; Kimambo, Offoro
Though innovations for sustainable management of natural resources have emerged over time, the rising demand for nature based health solutions and integration of endemic flora into global value chains could have adverse impacts on ecosystems. The ecological risks in the exploitation of wild medicinal plant resources are exacerbated by a myriad of agrotechnological risks and challenges that highly constrain their domestication. Successful exploitation and commercialization of medicinal plants thus require a clear understanding of their demand and production systems or value chain analysis. Accordingly there is need for innovative approaches towards their integration into global value chains. Since quality and safety, traceability, certification, as well as, consumer tastes and preferences are critical drivers in purchasing decisions by global consumers, they are inadvertently exploited to weaken Indigenous knowledge (IK), undermine common property rights and entrench value chains that favour a few elite buyers. This tend to create pervasive incentives for overexploitation of medicinal plant resources and environmental degradation. Potential solution lies in the recognition of drivers of vulnerability to environmental degradation and the innovative use of policy bricolage, feedback loops and interactions between knowledge, power and agency on one hand, and collective action and property rights institutions on the other hand. We conceptualise a framework that can mediate a transformational agenda and enhance systematic understanding of sustainability lenses in endemic medicinal plant resources value chains. This could in turn strengthen IK, enhance collective action and promote participation of local actors with positive impact on the utilisation and integration of endemic medicinal plant resources into global value chains.

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