Department of Geography and Environmental Sciences

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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.
Accumulation of SOC under organic and no-fertilizations, and its influence on crop yields in Tanzania’s semiarid zone
(Informa UK Limited, trading as Taylor & Francis, 2018-04-15) Mkonda, M. Y.; He, X.
Introduction: To estimate differential accumulation of soil organic carbon (SOC) and its ecological significance is very important to smallholder farmers in the Tanzania’s semiarid areas. This study investigated the accumulation of SOC and other important soil nutrients under organic and no-fertilizations, and correlated SOC with crop yields. Using data from long-term experimental study sites of semiarid in Tanzania, we estimated SOC accumulation in different soil treatments and depths where a total of 128 soil samples were collected at the depths of 0–20 cm and 20–40 cm from two villages (sites) with organic fertilization and nofertilization treatments. Sites under organic fertilization were defined as those which have received manure fertilization for more than 5 years on continuum basis. Outcomes: The accumulation of SOC was significantly greater in soils under organic fertilizations (1.15 and 0.80 MgC ha−1 at soil depth and 20–40 cm) and decreased with increasing soil depths. Similarly, TN and P decreased from 0.40 and 2.40 Mg (0–20 cm) to 0.16 and 2.10 Mg (20–40 cm), respectively. Other important soil nutrients such as calcium (Ca2+), potassium (K+), magnesium (Mg2+), and sodium (Na+) had similar pattern. In addition, soil bulk density was less under organic fertilization (1.1 g/cm3) than under no-fertilization (1.2 g/cm3) and it increased with soil depths. Correspondingly, the crop yields were significantly higher (1.6 tn ha−1) under organic fertilizations than (0.6 tn ha−1) under no-fertilizations indicating that crop yields were significantly affected by SOC. Discussion: Organic fertilization i.e., especially cattle manure in the area has considerable fertility potential. To optimize soil fertility potential, we need to consider such kind of fertilization from household to national level. Conclusion: Our results demonstrated that manure application was the best fertilization method for improving soil fertility in most croplands of Tanzania’s semiarid areas, especially in this era of climate change scenarios.
Agricultural history nexus food security and policy framework in Tanzania
(2018) Mkonda, M. Y.; He, X.
Background: Understanding the production trend of the major food crops is an important step for any nation that evaluates her agricultural progress. This evaluation should mostly focus on the yields per unit area. So far, it can also earmark the expansion of farms to determine the general yields trend. The main objective of this paper is to assess the production trend of the major food crops and their efficacy to food security in Tanzania. This is particular important because for the past three decades, the country has failed to control food security (especially food availability and accessibility). Results: Here, crop data from 1980 to 2015 were gathered from the Ministry of Agriculture, Livestock and Fishery (MALF), and in the respective regions. In some incidences, the regional data were averaged to elicit their preciseness. To determine the objectivity of this study, agricultural policy, programs, and plans from MALF were reviewed for similar purpose. Mostly, the Mann-Kendal Test and Microsoft Excel were used for data analyses. The results show that the production of the total yields had a positive trend (i.e., growing at R2 = 0.4 and 0.8), while that of the yields (ton/ha) had a negative trend (i.e., declining at R2 = 0.02 and 0.3). It was further realized that the total yields mostly boomed due to farm expansion. Conclusions: Despite the efforts from various agricultural stakeholders, the country has not yet achieved a sustainable crop yield and food security. Explicitly, this situation has been affecting peoples’ livelihoods, and other sectors either directly or indirectly. Therefore, there is a need to improve the production strategies and approaches (i.e., more especially technology and marketing) to limit this problem.
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.
Analyses of past extremes precipitation– evapotranspiration indices over Sub-saharan Countries
(World Scientific Publishing Company., 2022-08-31) Mbaye, Mamadou Lamine; Bodian, Amy; Kimambo, Offoro Neema; Rouamba, Fabienne Inès; Gaveta, Elias
Extreme weather and climate events including extreme precipitation have increased in frequency, intensity, and severity due to climate change and hit vulnerable communities disproportionately hard. However, there is a gap in the understanding of the characteristics of extreme precipitation and their effects on socio-economic activities in sub-Saharan Africa societies. The study utilized climate hazards group infrared precipitation with station data (CHIRPS) to analyze the climate characteristics from 1981 to 2019 over Senegal, Burkina Faso, Tanzania, and Malawi. Standardized precipitation evapotranspiration index (SPEI) and standardized precipitation index (SPI) were used to classify the precipitation and water balance anomalies with respect to the long-term observations. It was found that Burkina Faso and Senegal have a similar climate signal with more rainfall in Burkina Faso. Malawi recorded more rainfall than Tanzania. All the four countries recorded a high rainfall variability of extreme events. Standardized hydro climatic indices have shown that these sub-Saharan countries have suffered severe droughts which have negatively affected the socio-economic activities among the rural populations.
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
Are rainfall and temperature really changing? Farmer’s perceptions, meteorological data, and policy implications in the Tanzanian semi-arid zone
(Sustainability, 2017) Mkonda, M. Y.; He, X.
Although various climate models, statistical crop models and economic simulations have been established to determine the level of farmers’ vulnerability, there has been little systematic assessment of farmers’ perception towards climate change in association with meteorological analyses and policy implications in Tanzania. The results from this assessment will enhance the formation of robust policies that improve resilient livelihoods and the capacity to adapt to climate change and variability. This paper seeks to (i) reveal the farmers’ perception on variation, change of rainfall, and temperature in the Tanzanian semi-arid area; (ii) depict meteorological evidence for the perceived rainfall and temperature changes; (iii) assess the policy perception and responses for the changing climate; and (iv) discuss the correlation between farmers’ perception and meteorological data. Household surveys, informative interviews and discussions were employed during data collection. The Mann-Kendall Test and SPSS (version 20) were used for climate data analyses, while qualitative data were thematically analyzed. The results showed that from 1980 to 2015 the mean annual rainfall decreased ( R2 = 0.21) while temperature increased (R2 = 0.30). Even though majority farmers agreed with these results, they had not yet taken serious measures to curb the situation. Besides, Agricultural Policy has lightly addressed and enforced the implementations of adaptation strategies to reduce climate impacts and vulnerability. Thereby, creation of awareness and intensification of climate adaptation strategies is needed at both farm and policy level.
Assessing the impact of human activities on the health condition of the Lukosi River catchment using selected physico-chemical parameters as indicators of water quality
(Frontiers Water, 2024-11-15) Nyagongo, Ahmad A.; Ndibalema, Vedasto G.; Lalika, Makarius C. S.
The Lukosi River catchment plays a crucial role in the economic and ecological framework of the country, serving as a major contributor to the Great Ruaha River (GRR). This study aimed to assess the impact of human activities on the health of the Lukosi River by analyzing key water parameters. Three sampling sites across the catchment were selected, and water samples were collected and analyzed using the American Public Health Association technique. A one-sample t-test was used to measure the significance of the difference between the measured water quality parameters and the water quality criteria established by the Tanzania Bureau of Standards (TBS) and the World Health Organization (WHO). The results revealed mean values for various parameters: pH (8.67 ± 0.57), temperature (24.803 ± 1.361°C), EC (93.30 ± 3.34 mgL−1), BOD (14.85 ± 1.49 mgL−1), TDS (46.95 ± 1.55 mgL−1), total hardness (27.53 ± 1.28 mgL−1), DO (3.4 ± 0.53 mgL−1), turbidity (109.83 ± 40.99 mgL−1), NO2 (79.04 ± 0.73 mgL−1), Cu (6.07 ± 0.60 mgL−1), Ca (7.88 ± 0.36 mgL−1), Mn (0.16 ± 0.07 mgL−1), Cl (7.58 ± 3.97 mgL−1), F (0.12 ± 0.0008 mgL−1), SO4 (20.42 ± 4.12 mgL−1), Mg (1.92 ± 0.13 mgL−1), Zn (0.14 ± 0.11 mgL−1), Fe (3.56 ± 0.15 mgL−1), and NH3 (4.67 ± 0.51 mgL−1). Parameters such as DO, turbidity, NH3, NO3, and BOD significantly (p = 0.05) exceeded the permissible limits set by the TBS and the WHO. Furthermore, elements including Fe and Cu exceeded allowable limits. Moreover, the WQI was used to indicate that the water in the catchment is unsuitable for sustaining aquatic organisms and is unfit for domestic use. Household questionnaires and direct observations identified key human activities in the catchment: gardening (78.3%), agriculture (68%), livestock keeping (50%), sand mining (21%), and brick-making (21%). Less prevalent were car washing (7%) and fishing (4%). These findings underscore the urgent need for conservation efforts and sustainable management practices to safeguard the Lukosi River catchment (LRC).
Assessment of water, sanitation and hygiene practices on diarrhoea among under-five children in Temeke Municipality, Dar Es Salaam - Tanzania
(Sokoine University of Agriculture, 2021) Munissi, Hafidh S.
Water, sanitation and hygiene are essential determinants of both physical and mental human health and acts as the prerequisites for human development. For decades water, sanitation and hygiene have been treated as a single sector regardless of their impacts on human health. This study investigated WASH practices and associated infections among under-five children in selected wards of Temeke Municipality in Dar es Salaam region. The study was cross-sectional and involved 220 respondents randomly selected from three wards namely Azimio, Mtoni and Tandika. The study employed a mixed method approach, whereby both quantitative and qualitative data were obtained from the household survey and key informant (KI) interview. Quantitative data which were collected from household interviews with mothers and caregivers were analysed with the aid of IBM-Statistics SPSS v.20. The findings show that, 40% of all the respondents depend on public tap/ standpipe as their major sources of water. The findings revealed further that, the majority (99.6%) of the respondents were aware about the importance of washing hands; however, only 22.6% wash their hands with soap before meals and 45.2% use soap to wash hands after meals. The overall perception towards hand washing behaviour varied among the respondents; the majority (71.7%) reported to have been washing their hands. Others (17.8%) suggested that hand washing is hygienic, and 16.5% said it is a primary preventive measure against communicable diseases. Furthermore, findings in the present study on personal hygiene activities revealed that 79.1%, 43.4% and 35.6% of all the respondents cited bathing, wearing clothes (washing), and tooth brushing as leading. On the part of proper utilization of latrine, majority (60.8%) reported to have been washing their hands after visiting the toilet saying that it is a preventive measure against transmission of diseases, while 46.5% said they washed their hands just to keep them clean. Moreover, the study found that 9.1% of all the households have latrines that can be accessed within their plot. The study revealed further that, 96.5% of all the households in a range of 6-10 households share latrine facilities, which are located near their respective compounds. The most common type of latrine available in the study area was pour flush without water seal linked to pit (57.3%) in Tandika, 65.3% in Mtoni, and 36.3% in Azimio. The other type was traditional pit latrines, 47.6% of which are found in Azimio, 13.3% in Mtoni, and 1.3% in Tandika. In addition, only 26%of all the latrines available were clean and 6% had water available inside the facility. As for hand washing facilities, 97.4% of the respondents reported to use a bowl for hand washing and only 0.9% had tap connected to water distribution. About 1.7% reported to have facilities available inside the house right next to the latrine, 0.9% reported to have facilities outside the house within 10 metres and only 1.3% reported to have soap available at the facility. The respondents reported that, of all the widely known WASH related infection in the areas, diarrhoea was the leading accounting for 10% followed by cholera accounting for 7.8% of all other infections. Overall, the most vulnerable group to these infections was the under-five children accounting for 10.4% of the population. Moreover, 32.5%, 22.7%, and 17.3% of the respondents from Azimio, Mtoni and Tandika respectively suggested self- cleanliness as among the preventive measures against known water-borne diseases. Other measures were food safety from preparation to the actual eating as suggested by 32.5% from Azimio, 14.7% from Mtoni, and 6.7% from Tandika. Hand washing before meals was significantly associated with respondents’ contracting of diarrhoea (p ≤ 0.05). Generally, it can be concluded that water is still a problem in the informal settlements. Sanitary conditions and hygienic measures are even worse and these can be attributed to socio-economic factors such as income levels, education status, and place of residence. Factors such as hand washing behaviours during critical times, water treatment measures, and education levels were positively associated with diarrhoea incidences among the under-five. The study recommends that, both infrastructural improvement and education provision should be employed in these areas with the emphasis in awareness creation regarding public health and the importance of each practice. Both sanitation and hygiene should be dealt with separately as they both impact human health at large. Projects should be implemented based on the needs of the areas such as urban slums, informal settlements, and special groups such as children, elders, and women.
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.
Bandwidth prediction schemes for defining bitrate levels in SDN-enabled adaptive streaming
(PEARL, 2019) Al-Issa, Ali Edan; Bentaleb, Abdelhak; Barakabitze, Alcardo Alex; Zinner, Thomas; Ghita, Bogdan
The majority of Internet video traffic today is delivered via HTTP Adaptive Streaming (HAS). Recent studies concluded that pure client-driven HAS adaptation is likely to be sub-optimal, given clients adjust quality based on local feedback. In [1], we introduced a network-assisted streaming architecture (BBGDASH) that provides bounded bitrate guidance for a video client while preserving quality control and adaptation at the client. Although BBGDASH is an efficient approach for video delivery, deploying it in a wireless network environment could result in sub-optimal decisions due to the high fluctuations. To this end, we propose in this paper an intelligent streaming archi tecture (denoted BBGDASH +), which leverages the power of time series forecasting to allow for an accurate and scalable network- based guidance. Further, we conduct an initial investigation of parameter settings for the forecasting algorithms in a wireless testbed. Overall, the experimental results indicate the potential of the proposed approach to improve video delivery in wireless network conditions.
The biological importance of the Eastern Arc Mountains of Tanzania and Kenya
(Elsevier, 2006-10) Burgess, N.D.; Butynski, T.M.; Cordeiro, N.J.; Doggart, N.H.; Fjeldså, J.; Howell, K.M.; Kilahama, F.B.; Loader, S.P.; Lovett, J.C.; Mbilinyi, B.; Menegon, M.; Moyer, D.C.; Nashanda, E.; Perking, A.
The Eastern Arc Mountains are renown in Africa for high concentrations of endemic Received 17 June 2005 species of animals and plants. Thirteen separate mountain blocks comprise the Eastern Received in revised Arc, supporting around 3300 km 2 of sub-montane, montane and upper montane forest, less form 29 June 2006 than 30% of the estimated original forested area. At least 96 vertebrate species are endemic, Accepted 8 August 2006 split as follows: 10 mammal, 19 bird, 29 reptile and 38 amphibian species. This includes Available online 12 October 2006 four endemic or nearly endemic species of primate – the Sanje Mangabey, the Iringa Red Colobus, the Mountain Galago and the new Kipunji monkey that forms its own monotypic Keywords: genus. A further 71 vertebrate species are near-endemic. At least 800 vascular plant species Biodiversity conservation are endemic, almost 10% of these being trees. These endemics include the majority of the Eastern Arc Mountains species of African violet – Saintpaulia, a well-known flowering plant in Western households. Protected areas An additional 32 species of bryophytes are also endemic. Many hundreds of invertebrates Diversity are also likely to be endemic, with data for butterflies, millipedes and dragonflies indicating Endemism potential trends in importance. Seventy-one of the endemic or near-endemic vertebrates are threatened by extinction (8 critical, 27 endangered, 36 vulnerable), with an additional seven wide ranging threatened species. Hundreds of plant species are also threatened
Boundary layer perspective assessment of air pollution status in Wuhan city from 2013 to 2017
(Springer Nature Switzerland, 2019) Mbululo, Yassin; Qin, Jun; Yuan, Zhengxuan; Nyihirani, Fatuma; Zheng, Xiang
This study used daily air pollution data (PM2.5, PM10, SO2, NO2, CO, and O3) from nine monitoring stations inWuhan city to calculate the air quality index (AQI) from 2013 to 2017. Together with this data, L-band sounding data, ground meteorological data, and air mass back trajectories were also used to describe the dynamics of atmospheric boundary layer (ABL) during pollution process. Analysis of the results shows that, even though the city is still polluted, the number of polluted days was decreasing. Ranking the years in terms of pollution status shows that the year 2013 was the most polluted year while the year 2017 was the cleanest year. Average annual limit of PM10, PM2.5, and NO2 during these 5 years were 1.3~1.8, 1.5~2.7, and 1.2~1.5 times higher than the annual average acceptable limit, respectively. The average ratio of PM2.5/ PM10 for 5 years was 0.67 which signifies that a significant portion of PM2.5 accounted for the total mass of PM10. Moreover, the condition of ABL during the pollution process shows the dominance of strong ground inversion and weak to calm winds. These conditions are not favorable for horizontal and vertical mixing of air pollutants and prevent dilution of pollutants with clean air. Mean cluster analysis of air mass back trajectory shows that pollutants of local origin were more important than the trans-boundary movement of air pollutants. This indicates that the observed pollution in Wuhan was more of local origin
Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania
(Elsevier, 2015-12-26) Comte, Jean-Christophe; Cassidy, Rachel; Obando, Joy; Robins, Nicholas; Ibrahim, Kassim; Melchioly, Simon; Mjemah, Ibrahimu; Shauri, Halimu; Bourhane, Anli; Mohamed, Ibrahim; Noe, Christine; Mwega, Beatrice; Makokha, Mary; Join, Jean-Lambert; Banton, Olivier; Davies, Jeffrey
Study region: Coastal areas of Kenya (Kilifi County), Tanzania (Kilwa district) and Comoros (Ngazidja island), East Africa. Study focus: Research aimed to understand the physical and societal drivers of groundwa- ter accessibility and identify critical aspects of groundwater access and knowledge gaps that require further monitoring and research. Interdisciplinary societal, environmental and hydrogeological investigations were consistently undertaken in the three areas consid- ered as exemplars of the diversity of the coastal fringes of the wider region. This paper focuses on the hydrogeological outcomes of the research, framed within the principal socio-environmental issues identified. New hydrological insights: Results confirm the fundamental importance of coastal ground- water resources for the development of the region and the urgent need to match groundwater development with demographic and economic growth. Hydrogeological knowledge is fragmented, groundwater lacks a long-term monitoring infrastructure and information transfer from stakeholders to users is limited. Current trends in demog- raphy, climate, sea-level and land-use are further threatening freshwater availability. Despite possessing high-productivity aquifers, water quality from wells and boreholes is generally impacted by saltwater intrusion. Shallow large-diameter wells, following the tra- ditional model of these areas, consistently prove to be less saline and more durable than deeper small-diameter boreholes. However, promoting the use of large numbers of shallow wells poses a significant challenge for governance, requiring coherent management of the resource at local and national scales and the engagement of local communities.
Characteristics of atmospheric boundary layer structure during pm2.5 and ozone pollution events in Wuhan, China
(MDPI, 2018) Mbululo, Yassin; Qin, Jun; Hong, Jun; Yuan, Zhengxuan
In this study, we investigated six air pollutants from 21 monitoring stations scattered throughout Wuhan city by analyzing meteorological variables in the atmospheric boundary layer (ABL) and air mass backward trajectories from HYSPLIT during the pollution events. Together with this, ground meteorological variables were also used throughout the investigation period: 1 December 2015 to 30 November 2016. Analysis results during this period show that the city was polluted in winter by PM2.5 (particulate matter with aerodynamics of less than 2.5 microns) and in summer by ozone (O3). The most polluted day during the investigation period was 25 December 2015 with an air quality index (AQI) of 330 which indicates ‘severe pollution’, while the cleanest day was 26 August 2016 with an AQI of 27 indicating ‘excellent’ air quality. The average concentration of PM2.5 (O3) on the most polluted day was 265.04 (135.82) g/m3 and 9.10 (86.40) g/m3 on the cleanest day. Moreover, the percentage of days which exceeded the daily average limit of NO2, PM10, PM2.5, and O3 for the whole year was 2.46%, 14.48%, 23.50%, and 39.07%, respectively, while SO2 and CO were found to be below the set daily limit. The analysis of ABL during PM2.5 pollution events showed the existence of a strong inversion layer, low relative humidity, and calm wind. These observed conditions are not favorable for horizontal and vertical dispersion of air pollutants and therefore result in pollutant accumulation. Likewise, ozone pollution events were accompanied by extended sunshine hours, high temperature, a calm wind, a strongly suspended inversion layer, and zero recorded rainfall. These general characteristics are favorable for photochemical production of ozone and accumulation of pollutants. Apart from the conditions of ABL, the results from backward trajectories suggest trans-boundary movement of air masses to be one of the important factors which determines the air quality ofWuhan.
Chemical composition and deposition fluxes of water-soluble inorganic ions on dry and wet deposition samples in Wuhan, China
(MDPI, 2019) Qin, Jun; Mbululo, Yassin; Yang, Muyi; Yuan, Zhengxuan; Nyihirani, Fatuma; Zheng, Xiang
Measurement of PM2.5 concentration, dry and wet deposition of water-soluble inorganic ions (WSII) and their deposition flux was carried out. During sampling, a total number of 31 samples of PM2.5, five wet deposition samples and seven dry deposition samples were collected. The analyses results showed that the average concentration of PM2.5 was 122.95 g/m3 whilst that of WSII was 51.63 g/m3, equivalent to 42% of the total mass of PM2.5. The correlation coefficients between WSII in samples of PM2.5 was significant (r = 0.50 and p-value of 0.0019). Ions of SO2􀀀 4 , NO􀀀 3 , Cl􀀀, and NH+ 4 were dominant in the entire samples (PM2.5, dry and wet depositions), nevertheless, the average concentration of both SO2􀀀 4 and Cl􀀀 were below the China environmental quality standard for surface water. The ratio of dominant anions in wet deposition (SO2􀀀 4 /NO􀀀 3 ) was 1.59, whilst that for dry deposition (SO2􀀀 4 /Cl􀀀) was 1.4, indicating that acidity was mainly derived from sulphate. In the case of dominant cations, the dry and wet deposition ratios (Ca2+/NH+ 4 ) were 1.36 and 1.37, respectively, suggesting the alkaline substances were mainly dominated by calcium salts. Days with higher recorded concentrations of PM2.5 were accompanied by dry and warm boundary layer structure, weak low-level wind and strong inversion layer.
Climate change and harsh weather conditions in developing countries: implications on water resources, public health and food security
(International Journal of Scientific & Engineering Research,, 2013) Okoyeh, E. I.; Egboka, B.C.E.; Anike, O.L.; Enekwechi, E.K.; Mjemah, I.C.
The changes in weather and climate in Nigeria and other developing countries have precipitated ecological and health problems. Variations in rainfall pattern/amount have resulted in negative implications on water resources, agriculture and food security. Surface waters are affected by the prevailing climate change resulting in the drying/total loss. Excessive evaporation with attendant heavy rainfall causes water pollution/contamination, erosion and landslide. Low crop yields due to change in rainfall amount results in food insecurity and increase in poverty. The sudden severe climatic changes with attendant rapid southward desert encroachment encourage migration. Many ensuing diseases such as malaria, meningitis, diarrhea, bronchitis, asthma, eye problem, cholera and typhoid attributed to the recent climate change are commonplace. The resultant implications are more severe in the rural areas and disproportionately affect the rural poor especially women and children. Public health and food security implications of the recent climate changes are yet to receive the deserved attention. The ecological scourge of heat waves, desertification, windstorms, flood disasters, soil and gully erosion and pollution of water resources require multi-objective and integrated approach and management measures. Involvement of expertise from relevant fields in climatic change study for the containment of the resultant global implications is recommended.
Climate change impacts and adaptation among coastal and mangrove dependent communities: a case of Bagamoyo district
(2012) Mbwambo, J.S; Madalla, D; Zahabu, E; Ndelolia, D; Mnembuka, B; Lamtane, H. A; Mwandya, A. W
The study was done to determine perception, impacts and adaptation of coastal communities towards climate change. A total of three villages and 120 respondents were involved in the study. Both Focus Group Interviews and a structured questionnaire survey were employed for collection of both qualitative and quantitative data. Content and structural functional analysis was used for qualitative data while descriptive and logistic and regression analysis was employed for quantitative data. Results indicates that majority of the community are involved in both fishing and farming activities for both food and cash income. Results indicates further that majority of the respondents are aware of climate change and they perceive the same in relation to unusual rainfall (87.5%), drought (93.3%), floods (74.1%) and increased incidence of pest and diseases (55.8%). It was also found that farmers are coping with food insecurity as a result of declining food stocks and they have also developed adaptation strategies related to farming operations and livelihoods. However, adaptation varies depending on various farm and household factors and in this income, number of plots, extension services and farm size were highly significant and showed strong positive influence on adaptation to climate change. It is concluded that farmers are aware of climate change and have developed both coping and adaptation strategies against climate hazards. Promotion of extension and enhancement of off-farm activities are recommended for enhancing adaptive capacity of the population in the study area.
Climate characteristics over southern highlands Tanzania
(Scientific Research, 2012) Mbululo, Yassin; Nyihirani, Fatuma
This study was conducted to examine the climate characteristic of southern highland Tanzania (Latitude 6°S - 12°S and Longitude 29°E - 38°E). The study findings reveal that rainfall over the region is linked with SST over the Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high (low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger) equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act to reduce (enhance) the export of equatorial moisture away from East Africa. The wettest (driest) season was found to be 1978/79 (1999/00) which can be classified as the severely wet (moderate drought). Two different modes of rainfall have been identified at time scale of 1.5 and 6 years which have been associated with the quasi biennial oscillation (QBO) and El Nino Southern Oscillation (ENSO), respectively.
Climate variability and crop yields synergies in Tanzania’s semiarid agroecological zone
(Informa UK Limited, trading as Taylor & Francis, 2018) Mkonda, M. Y.; He, X.
The consequences of climate change have been considerably high to smallholders in most of Sub-Saharan Africa. These impacts have been more enormous to crop production and other attached livelihoods. However, the comprehensive assessment of these impacts has suffered numerous challenges because crop productivity is also susceptible to other factors involved in the production process. This study aimed to understand how crop yields are affected by climate change in the semiarid zone of Tanzania. The findings would establish a thorough literature within smallholder adaptation in the area. Furthermore, they will intensify strategies to cope with reduced yields attributed by climate-change impacts. Outcomes: There has been a dramatic decrease in rainfall (R2 = 0.21) and increase in temperature (R2 = 0.30). In addition, we found that rainfall and temperature variability had positive (R2 ~ 0.5) and negative (R2 ~ 0.3) correlations with crop yields, respectively. Discussion: The decline in yields at both local and national levels elevated the magnitude of food shortage and poverty. The increasing climate impacts necessitate undertakings of various studies to plan, design, recommend, and implement various useful adaptation measures, especially in the vulnerable communities. Conclusion: To limit climate effects, we need to increase investments in adaptation and mitigation measures.

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