Browsing by Author "Munishi, Linus"

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Accumulation and bioconcentration of heavy metals in two phases from agricultural soil to plants in Usangu agroecosystem-Tanzania
(Heliyon, 2021-07-07) Mng’ong’o, Marco; Munishi, Linus; Ndakidemi, Patrick; Blake, William; Comber, Sean; Hutchinson, Thomas
The build-up of heavy metals (HM) in agricultural soils accelerates the HM uptake by plants, which could potentially affect food quality and food safety. Here we studied the status and bioaccumulation of HM from soils to plant parts (roots, stem, and grains) in Usangu agro-ecosystem-Tanzania. In total 68 soil samples and 42 rice plant samples from six irrigation schemes were studied. The concentrations of cadmium-Cd, chromium-Cr, copper-Cu, lead-Pb, zinc-Zn, nickel-Ni, and iron-Fe were determined to estimate accumulation, distribution, bioconcentration. Total soil HM concentration in soil and plant samples was determined by acid digestion. The concentration of HM in soils samples (in mg/kg) were Cr (4.58–42.76), Co (1.486–6.12), Fe (3513.56–12593.99), Zn (7.89–29.17), Cd (0.008–0.073), Cu (0.84–9.25), Ni (0.92–7.98), and Pb (1.82–18.86). The total HM concentration in plant samples were (in mg/kg) were Cu (5.18–33.56), Zn (57.03–120.88), Fe (963.51–27918.95), Mn (613.15–2280.98), Cd (4.3–17.46), Pb (0.01–28.25), Cr (12.88–57.34) and Ni (9.65–103.33). The concentration of HM in soil and plant parts was observed to vary among locations where high concentrations of HM were detected in stems and roots compared to grains. The ratio HM in plants and soil samples (bioconcentration) was higher than one for some sites indicating higher HM uptakes by plants leading to possible health risk to soil invertebrates, animals, and humans. The bioconcentration factor varied among schemes, with the highest values at Igalako and Mahongole, which could be caused by artisanal gold mining and mining quarry existed in the area. Therefore, steps are needed to reverse the situation to balance the HM in agricultural soils and plant tissues to be within acceptable limits. Keywords
Assessing the Ethnobotanical Uses, Harvesting Practices, and Conservation Awareness of Warburgia ugandensis in Northern Tanzania
(Scientific Research Publishing, 2024-12-09) Mollel, Letan; Munishi, Linus; Giliba, Richard
Warburgia ugandensis is unsustainably harvested commercially, threatening its survival and potentially leading to local extinction in its native range areas in Northern Tanzania. Our study aimed to assess the extent of harvesting of W. ugandensis in Northern Tanzania, ethno-botanical uses, community perceptions of species utilization, and conservation measures across its native range in Northern Tanzania. From each of the 128 randomly selected grids, we laid down a sampling plot measuring 100 m × 100 m (1 ha) for the identification, and collection of data on the extent of harvesting of W. ugandensis. Additionally, we interviewed 221 respondents using open-ended questionnaires to gather data on ethno-botanical uses, perceptions of product utilization, and conservation measures. We analyzed the data using descriptive statistics and Kruskal-Wallis tests. Our findings reveal significant variation in the extent of harvesting, with Mt. Ketumbeine experiencing the most severe harvesting while Mt. Kilimanjaro holds the highest number of intact trees. Community knowledge of the medicinal uses of W. ugandensis was highest in Mt. Kilimanjaro, particularly for treating gastrointestinal disorders, coughs, and malaria. Perceptions of species utilization were very high in Mt. Gelai and Mt. Monduli, while Mt. Kilimanjaro, Ketumbeine, and Longido showed more variability. Awareness of W. ugandensis conservation measures was high in Mt. Kilimanjaro, compared to the rest of the species’ native range areas. Therefore, our study findings underscore the urgent need for targeted conservation initiatives, particularly in regions like Mt. Ketumbeine and Mt. Longido, where W. ugandensis faces the severe extent of harvesting.
Assessing Vulnerability of Food Availability to Climate Change in Hai District, Kilimanjaro Region, Tanzania
(Scientific Research Publishing Inc, 2014-09) Lema, Anza; Munishi, Linus; Ndakidemi, Patrick
Climate change has a large effect on agriculture sector and, consequently, on the food available for residents of Hai District and other regions of Tanzania. Based on four decades of climate data, this study assessed the impacts of climate change and its potential vulnerability on food availability in Hai District, Kilimanjaro region. The results from this study suggest an association between food crop production and variation in climate (temperature and rainfall) in Hai District. Considering the aspect of rainfall and temperature, we demonstrate that rainfall and temperature have significant relationship with maize and bean outputs. The rainfall had a strong positive association with maize and beans production and whereas temperature had inverse relationship with maize and beans yields. With the annual loss $0.04 million and $0.01 million per year from cattle and goats/sheep respectively and the additional annual loss of $29 million and $10.8 million from maize and bean crops respectively in Hai District during years of severe and prolonged droughts, our study highlighted how severe droughts can dramatically affect agriculture production and food security in the area. To mitigate climate change and provide effective adaptation measures, it is imperative to develop a broader research framework, which integrates bio-physical and socioeconomic aspects of food systems which addresses its vulnerability and thereby improve food security.
Assessment of arsenic status and distribution in Usangu agro-ecosystem-Tanzania.
(Elsevier Ltd., 2021-06-09) Mng'ong'o, Marco; Comber, Sean; Munishi, Linus; Blake, William; Ndakidemi, Patrick; Hutchinson, Thomas H
This study was conducted to assess arsenic (As) status and distribution in Usangu agroecosystem-Tanzania, including three land use. About 198 soil samples were collected in ten irrigation schemes in three land uses. Total and bioavailable As were determined by acid digestion (Aqua regia (AQ)) and Mehlich 3 method (M3) to estimate status, distribution and bioavailability. Arsenic concentration were variable among land use and irrigation schemes where total arsenic ranged 567.74-2909.84 μg/kg and bioavailable As ranged 26.17-712.37 μg/kg. About 12-16% of total arsenic were available for plant uptake. Approximately 86.53% of studied agricultural soils had total As concentration above Tanzania maximum allowable limit. Bioavailable As were lower compared to total As and were within the acceptable threshold. Total arsenic concentration were variable among schemes and higher values were observed in schemes which are highly intensified and mechanized. Thus, this study provides essential site specific preliminary baseline information for As status and distribution in agricultural soils to initiate monitoring and management strategies for increased land productivity and environmental safety.
Balancing African Elephant Conservation with Human Well-Being in Rombo Area, Tanzania
(Hindawi Advances in Ecology, 2017-05-31) Mmbaga, Naza; Munishi, Linus; Treydte, Anna
The critical assessment of the nature and extent of human-elephant conflict (HEC) and its impact on conservation efforts are essential if we are to meet the challenges related to extinction of local population, as well as loss biodiversity. Conservationists need detailed information on HEC in areas where these challenges prevail to improve intervention in the face of limited funds/resources. We assessed the status of HEC at Rombo area over the last six years. Data based on household surveys, focus group discussions, spatiotemporal analysis of site observations, and reported incidents of damage within the last six years were mapped. Out of all HEC cases analyzed, the most were crop damage which took place at night and the damage was severe between May and July, when cereal crops were mature. In upland areas of Rombo, HEC hotspots were observed inside the protected forest plantation where local people cultivated their annual crops. Cold spots concentrated in upland areas outside the protected forest plantation dominated by settlement and agroforestry less preferred by elephants. In lowland areas,HEChotspotswere observed in village lands close to the PAs, within settlement and farmland dominated by seasonal crops. This suggests that HEC management efforts such as establishment of buffer zones should be directed around the areas adjacent to PAs and prevention should focus on cultivation of the alternative crops and farming systems that are less preferred by elephants. Our study highlights the importance of using a combination of data collection techniques to pinpoint fine-scale HEC hotspots in a highly conflict-prone location of Tanzania.
Can Cynodon dactylon Suppress the Growth and Development of the Invasive Weeds Tagetes minuta and Gutenbergia cordifolia?
(MDPI, 2019-12-06) Ngondya, Issakwisa; Treydte, Anna; Ndakidemi, Patrick; Munishi, Linus
Approaches to managing invasive plants is challenging, particularly in protected areas where conventional methods, such as chemical herbicide applications are limited. We studied the effects of varying densities of Cynodon dactylon on the growth and development of the invasive weeds Tagetes minuta and Gutenbergia cordifolia in northern Tanzania. We conducted pot and field plot experiments following a completely randomized block design that was replicated three times. Increasing densities of C. dactylon significantly reduced growth, leaf total chlorophyll, biomass and significantly increased leaf anthocyanin of both T. minuta and G. cordifolia invasives. Our results further showed that the critical density of C. dactylon to suppress the two invasive species is ≥ 8 plants/m2. We suggest that C. dactylon can successfully be used as an alternative eco-friendly and sustainable approach for managing invasive weeds, such as T. minuta and G. cordifolia. This management technique can additionally improve forage production and biomass for wild and domestic herbivores in the affected areas.
Characterization of land use influence on soil phosphate bioavailability in Usangu agro-ecosystem-Tanzania
(Elsevier B.V., 2021-12) Mng’ong’o, Marco; Munishi, Linus; Ndakidemi, Patrick
Phosphorus (P) is an important nutrient required for plant growth. Land use influences concentration and bioavailability of P in agricultural soils. About 198 soil samples (0-30 cm soil depth) were collected from three land-use types (maize, paddy, and conserved areas) in Usangu basin located in Southern Highland Tanzania. The concentration of soil P determined were compared among different land-use types and locations. The total P (TP), complexed (Po), and bioavailable P (B-P) were measured. The concentration of TP and B-P was determined by acid digestion and Mehlich 3 method, respectivelly, The Po concentration in soil extract was obtained by subtracting B-P from TP. TP, B-P and Po concentration in collected soils samples were in range of; Total P (63.12-1350.9 mg/kg), Bioavailable P (0.52-49.87 mg/kg), and complexed P (62.60-1301.03 mg/kg). The cropping area had high TP but very low B-P, especially in paddy farming areas indicating cropping and associated activity decrease bioavailable P in agricultural soils. Furthermore, soils from cropping areas had higher Al, Fe, and Mg concentrations than conserved areas, which caused a substantial reduction in B-P due to increased P fixation and adsorption. It is important to note that converting natural land to farming land could potentially influence soil P dynamics thus affecting P bioavailability, crop productivity, and environmental safety.
Characterization of soil phosphate status, sorption and saturation in paddy wetlands in usangu basin-Tanzania
(Elsevier Ltd., 2021-09) Mng’ong’o, Marco; Munishi, Linus; Blake, William; Ndakidemi, Patrick; Comber, Sean; Hutchinson, Thomas
Phosphorus (P) is a vital plant macronutrient required for plant growth which usually available in limited amount. P availability for plant uptake in highly weathered soil is controlled by soil erosion and high fixation. The availability of P applied from fertilizers depend on the soil pH, soil sorption capacity (PSC) and P saturation status (PSD), which determines P storage, losses, fixation, and additional P to be added with minimal loss to the environment. PSC and PSD are agroenvironmental indicators used to estimate P availability and P loss to the environment. However, PSC and PSD of agricultural soils had been never studied in Tanzanian soils. This study was conducted to assess and estimate P availability, PSC and PSD and the risks of P losses in tropical soils from Usangu basin popular for paddy farming. In total, 198 soil samples from 10 paddy irrigation schemes were collected (November–December 2019) and analyzed for inherent P (PM3), metal oxides of Aluminium (Al M3), iron (Fe M3), and calcium (Ca M3) as main PSC and PSD determinant. The determined concentrations were in range of; P M3 014.9–974.69 mg/kg, Al M3 234.56–3789.36 mg/kg, Fe M3 456.78–2980.23 mg/kg, and Ca M3 234.67–973.34 mg/kg. Estimated PSCM3 ranged 5.62–34.85 mmol/kg with a mean value of 14.14 mmol/kg corresponding to high status, ensuring high P holding capacity for plant uptake. However, some soils had very low PSCM3 creating a risk of P loss to environment. Among soils, the estimated PSD M3 ranged from 0.01 to 17.57% and was below (<24%), indicating low P loss risks to surface and groundwater, however, some soils were observed to have PSDM3 above 15% which correspond to a critical degree of phosphate saturation of 25% in a watershed using oxalate extraction method. Therefore some sites were associated with high P loss to the environment, immediate and precautionary actions for sustainable P management to increase productivity, environmental safety and sustainability are needed to be in place.
Climate change and decline in water resources in Kikuletwa Catchment, Pangani, Northern Tanzania
(African Journal of Environmental Science and Technology, 2014-01) Munishi, Linus; Sawere, Pudensiana
The sensitivity of hydrology and water resources to climate variation in Kikuletwa Catchment, Pangani Basin, northern Tanzania was assessed using 30 years of river level and climate data as well as questionnaire, focused group discussion (FGD) and participant observation. The results show a significant association between mean annual river level for Kikuletwa River and mean annual rainfall in the past thirty years. The results further indicate an inverse relationship between river level and temperature in the catchment suggesting the effects of climate change on water resources at Kikuletwa Catchment area. Although the results of our study indicate an upward trend in precipitation (from the two rain stations) over the past three decades, there was a consistent decline in river level in the main rivers. The eight villages covered by this study face a variety of water shortage and environmental challenges that are intertwined with the causes and consequences of a changing climate. Access to water is the primary natural resource concern in Pangani Basin and Kikuletwa catchment villages and a lack of infrastructure for storing and directing water during rainy periods limits opportunities for harvesting water for irrigation and other household uses. More than seventy percent of heads of household are farmers whose crop production depends mainly on rainfall. While water deficit remains a major concern, its severity is not immune to the challenges of shifting climate and environmental destruction resulting from livelihood activities in the study area.
Climate-smart solutions for tropical mountain environments
(Frontiers, 2024-02-15) Munishi, Linus; Kimaro, Didas; Feger, Karl; Desie, Ellen
Comparative Assessment of UAV and Sentinel-2 NDVI and GNDVI for Preliminary Diagnosis of Habitat Conditions in Burunge Wildlife Management Area, Tanzania
(MDPI, 2022-06-28) Mangewa, Lazaro; Ndakidemi, Patrick; Alward, Richard; Kija, Hamza; Bukombe, John; Nasolwa, Emmanuel; Munishi, Linus
Habitat condition is a vital ecological attribute in wildlife conservation and management in protected areas, including the Burunge wildlife management areas in Tanzania. Traditional techniques, including satellite remote sensing and ground-based techniques used to assess habitat condition, have limitations in terms of costs and low resolution of satellite platforms. The Normalized Difference Vegetation Index (NDVI) and Green NDVI (GNDVI) have potential for assessing habitat condition, e.g., forage quantity and quality, vegetation cover and degradation, soil erosion and salinization, fire, and pollution of vegetation cover. We, therefore, examined how the recently emerged Unmanned Aerial Vehicle (UAV) platform and the traditional Sentinel-2 differs in indications of habitat condition using NDVI and GNDVI. We assigned 13 survey plots to random locations in the major land cover types: three survey plots in grasslands, shrublands, and woodlands, and two in riverine and mosaics cover types. We used a UAV-mounted, multi-spectral sensor and obtained Sentinel-2 imagery between February and March 2020. We categorized NDVI and GNDVI values into habitat condition classes (very good, good, poor, and very poor). We analyzed data using descriptive statistics and linear regression model in R-software. The results revealed higher sensitivity and ability of UAV to provide the necessary preliminary diagnostic indications of habitat condition. The UAV-based NDVI and GNDVI maps showed more details of all classes of habitat conditions than the Sentinel-2 maps. The linear regressions results showed strong positive correlations between the two platforms (p < 0.001). The differences were attributed primarily to spatial resolution and minor atmospheric effects. We recommend further studies to test other vegetation indices.
Connectivity between land, water, and people: integrating process concepts and assessment evidence across disciplines for co-design of soil erosion solutions
(Authorea, 2020-04-20) Blake, William; Kelly, Claire; Wynants, Mona; Patrick, Aloyce; Lewin, Shaun; Lawson, Joseph; Nasolwa, Emmanuel; Page, Annabel; Nasseri, Mona; Marks, Carey; Gilvear, David; Mtei, Kelvin; Munishi, Linus; Ndakidemi, Patrick
Soil resources in East Africa are being rapidly depleted by erosion, threatening food-, water- and livelihood security in the region. Here we demonstrate how integration of evidence from natural and social sciences has supported community-led change in land management in an agro-pastoral community in northern Tanzania impacted by soil erosion. Drone survey data and geospatial analysis of erosion extent and risk, supported by communication of ‘process’ and ‘structural’ hydrological connectivity, was integrated with local environmental knowledge within participatory community workshops. Rill density data were compared between cultivated plots that had been converted from pastoral land recently and more established plots where slow-forming terrace boundaries were more established. Slope length and connectivity between plots were key factors in development of rill networks. At the two extremes, recently converted land had a rill density ca 14 times greater than equivalent established slow forming terraces. Direction of cultivation, regardless of plot boundary orientation with contours, also enhanced rill development. Evidence of this critical time window of hillslope-scale rill erosion risk during early phases of slow-forming terrace development successfully underpinned and catalysed a community-led tree planting and grass seed sowing programme to mitigate soil erosion by water. This was grounded in an implicit community understanding of the need for effective governance mechanisms at both community and District levels, to enable community-led actions to be implemented effectively. The study demonstrates the wide-reaching impact of integrated and interdisciplinary ‘upslope-downslope’ thinking to tackle global soil erosion challenges.
Conservation and Management Challenges Facing a Medicinal Plant Zanthoxylum chalybeum in Simanjiro Area, Northern Tanzania
(MDPI, 2020-05-19) Mbinile, Scholastica; Munishi, Linus; Ngondya, Issakwisa; Ngondya, Issakwisa; Ndakidemi, Patrick
The information on the medicinal use, availability, challenges, and future conservation strategies for the medicinal plant Zanthoxylum chalybeum were gathered by using a semi-structured questionnaire, focused group discussions, and field observations in Simanjiro Area, Tanzania. Data were collected from local village members who were familiar with the tree and the key informants. Data were analyzed using Statistical Package for the Social Sciences (SPSS). The extent of use was found to be very high, with more than three-quarters of harvested parts used for treating women’s health system (86.4%). The most used plant parts for medicinal purposes were reported to be the roots and the stem bark (90.3% and 81.6%, respectively), possibly suggesting mortality caused by heavy harvesting. In addition to unsustainable harvesting methods, minimal and unpredictable propagation methods were the key factors affecting the recruitment rate, with perhaps an addition of continued climate and land-use change (93.2%), indicative of low precipitation and high agriculture and settlement expansions. Given these challenges, the future conservation and persistence of Z. chalybeum looks uncertain, which requires such measures as the provision of education and awareness and ensuring proper land-use plans that encompass active recruitment of the species in these areas.
Conservation and Management Challenges Facing a Medicinal Plant Zanthoxylum chalybeum in Simanjiro Area, Northern Tanzania
(MDPI, 2020-05-19) Mbinile, Scholastica; Munishi, Linus; Ngondya, Issakwisa; Ndakidemi, Patrick
The information on the medicinal use, availability, challenges, and future conservation strategies for the medicinal plant Zanthoxylum chalybeum were gathered by using a semi-structured questionnaire, focused group discussions, and field observations in Simanjiro Area, Tanzania. Data were collected from local village members who were familiar with the tree and the key informants. Data were analyzed using Statistical Package for the Social Sciences (SPSS). The extent of use was found to be very high, with more than three-quarters of harvested parts used for treating women’s health system (86.4%). The most used plant parts for medicinal purposes were reported to be the roots and the stem bark (90.3% and 81.6%, respectively), possibly suggesting mortality caused by heavy harvesting. In addition to unsustainable harvesting methods, minimal and unpredictable propagation methods were the key factors affecting the recruitment rate, with perhaps an addition of continued climate and land-use change (93.2%), indicative of low precipitation and high agriculture and settlement expansions. Given these challenges, the future conservation and persistence of Z. chalybeum looks uncertain, which requires such measures as the provision of education and awareness and ensuring proper land-use plans that encompass active recruitment of the species in these areas
Cropping patterns along an altitudinal gradient and their implications to wildlife conservation in Rombo, Tanzania
(Elsevier B.V., 2021-08) Mmbaga, Naza; Munishi, Linus; Treydte, Anna
Ecosystem and livelihood sustainability of small-scale farmers in Eastern Africa are often challenged by climate change and unsustainable land use practices. Little is known on the small-scale temporal processes of cropping systems in relation to long-term climatic conditions. To understand the climatic influence on the cropping patterns, and its implications to wildlife/elephant conservation, our study used a combination of time-series datasets on crop and climate as well as geo-spatial layers spanning more than three decades. To validate the information analyzed from secondary data, we carried out participatory observation and interviews, whereby about 5% of village households were selected along an altitudinal gradient of Rombo area, Tanzania. We generated land use change maps using Geographical Information System (ArcGIS 10.4) and used Spearman’s correlation analysis to assess the influence of rainfall, temperature, and crop yield on the observed longitudinal changes in the crop types and other land use patterns both within and across altitudinal gradients. We found that perennial crops like coffee and banana concentrated in upper agro-ecological zones, with a clear division line above 1230 masl while seasonal crops like maize and beans were mostly cultivated in lowlands (below 1230 masl). The results further showed that coffee yields significantly declined with higher average annual minimum temperatures over the last 16 years. Within the same time period, there was a disproportionate shift from coffee to seasonal crop cultivation such as maize and beans. Elephant numbers declined by about 38%, while human settlement area increased by 28% over the last 30 years. We conclude that changes in land use and shifts in climate and cropping patterns have important implications for elephant conservation and sustainability of the ecosystem in Rombo area, Tanzania.
Culex quinquefasciatus mosquito avoids ovipositing in habitats with the annual fish (Nothobranchius neumanni) in Tanzania
(Springer Netherlands, 2024-05-03) Mataba, Gordian; Munishi, Linus; Brendonck, Luc; Vanschoenwinkel, Bram
Mosquitoes are known to choose oviposition habitats actively based on their suitability for survival of their offspring. They thus avoid laying eggs in dangerous habitats with aquatic predators through detection of their cues. Visual, tactile, and chemical cues emitted by certain predators have been shown to reduce oviposition in some mosquitoes, which in turn may affect their adult population sizes. However, those tests tend to be limited to species from temperate regions. Moreover, mosquito oviposition response to predator cues have been shown to be predator specific, but this has not been investigated for many potential predators worldwide. In the African subtropics, temporary ponds can be important mosquito breeding habitats and the same habitats are also used by a group of specialized killifish that can survive dry periods using drought resistant eggs. Although they are reported as mosquito predators, it is unknown whether mosquitoes actively avoid laying eggs in ponds with annual killifish. We investigated this using the mosquito Culex quinquefasciatus and the free and caged killifish Nothobranchius neumanni in the outdoor mesocosm experiments in Tanzania. We found that Cx. quinquefasciatus had 71% lower oviposition in mesocosms with free swimming killifish and 68% lower oviposition in mesocosms with caged killifish. We conclude that predator-released chemical cues alone are enough to explain the observed responses. If the cues can be isolated and chemically identified can be developed into a biological mosquito control strategy and used to safeguard public health in areas where mosquito borne diseases are endemic.
Curbing the major and growing threats from invasive alien species is urgent and achievable
(Nature Publishing Group UK, 2024-06-03) Roy, Helen; Pauchard, Aníbal; Stoett, Peter; Truong, Tanara; Meyerson, Laura; Bacher, Sven; Galil, Bella; Hulme, Philip; Kavileveettil, Sankaran; McGeoch, Melodie; Nuñez, Martin; Ordonez, Alejandro; Mungi, Ninad; Munishi, Linus
Although invasive alien species have long been recognized as a major threat to nature and people, until now there has been no comprehensive global review of the status, trends, drivers, impacts, management and governance challenges of biological invasions. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Thematic Assessment Report on Invasive Alien Species and Their Control (hereafter ‘IPBES invasive alien species assessment’) drew on more than 13,000 scientific publications and reports in 15 languages as well as Indigenous and local knowledge on all taxa, ecosystems and regions across the globe. Therefore, it provides unequivocal evidence of the major and growing threat of invasive alien species alongside ambitious but realistic approaches to manage biological invasions. The extent of the threat and impacts has been recognized by the 143 member states of IPBES who approved the summary for policymakers of this assessment. Here, the authors of the IPBES assessment outline the main findings of the IPBES invasive alien species assessment and highlight the urgency to act now.
Dataset: SNP genotyping of indigenous goats of Uganda based on the Goat_IGGC_65K_v2 illumina chip
(2024-05-23) Nantongo, Ziwena; Birungi, Josephine; Obol Opiyo, Stephen; Shirima, Gabriel; Mugerwa, Swidiq; Mutai, Collins; Kyalo, Martina; Munishi, Linus; Agaba, Morris; Mrode, Raphael
Uganda's indigenous goats are characterised based on ethnic communities that raise them, average mature weight, and hair coat characteristics. Uganda's indigenous goats have been genotyped based on the Goat_IGGC_65K_v2 illumina chip to study their population structure and genetic characteristics. Information generated from this data is vital for the sustainable utilisation, development, and conservation of Uganda's goat genetic resources.
Decline in maize and beans production in the face of climate change at Hai District in Kilimanjaro Region, Tanzania
(Emerald Group Publishing Limited, 2015) Munishi, Linus; Lema, Anza; Ndakidemi, Patrick
Purpose – The purpose of this paper is to show how climatic change in Africa is expected to lead to a higher occurrence of severe droughts in semiarid and arid ecosystems. Understanding how crop productions react to such events is, thus, crucial for addressing future challenges for food security and poverty alleviation. Design/methodology/approach – The authors explored how temperature and rainfall patterns determined maize and beans production in Hai District in Kilimanjaro Region, Tanzania. Findings – Annual food crops were particularly sensitive to the drought and maize and beans yields were lower than perennial crops during the years of drought. The authors also report strong and significant association between maize and beans production with temperature and rainfall patterns. Practical implications – This study highlights how severe droughts can dramatically affect yields of annual crops and suggests that extreme climatic events might act as a major factor affecting agriculture production and food security, delaying or preventing the realization of the Millennium Development Goals. Originality/value – This is the first study that highlights how severe droughts can dramatically affect yields of annual crops in Hai District contributing to other climate studies done elsewhere in Tanzania and the world at large.
A deconvolutional Bayesian mixing model approach for river basin sediment source apportionment
(Scientific Reports, 2018-08-30) Blake, William; Boeckx, Pascal; Stock, Brian; Smith, Hugh; Bodé, Samuel; Upadhayay, Hari; Gaspar, Leticia; Goddard, Rupert; Lennard, Amy; Lizaga, Ivan; Lobb, David; Owens, Philip; Petticrew, Ellen; Kuzyk, Zou; Gari, Bayu; Munishi, Linus; Mtei, Kelvin; Nebiyu, Amsalu; Mabit, Lionel; Navas, Ana; Semmens, Brice
Increasing complexity in human-environment interactions at multiple watershed scales presents major challenges to sediment source apportionment data acquisition and analysis. Herein, we present a step-change in the application of Bayesian mixing models: Deconvolutional-MixSIAR (D-MIXSIAR) to underpin sustainable management of soil and sediment. This new mixing model approach allows users to directly account for the ‘structural hierarchy’ of a river basin in terms of sub-watershed distribution. It works by deconvoluting apportionment data derived for multiple nodes along the stream-river network where sources are stratified by sub-watershed. Source and mixture samples were collected from two watersheds that represented (i) a longitudinal mixed agricultural watershed in the south west of England which had a distinct upper and lower zone related to topography and (ii) a distributed mixed agricultural and forested watershed in the mid-hills of Nepal with two distinct sub-watersheds. In the former, geochemical fingerprints were based upon weathering profiles and anthropogenic soil amendments. In the latter compound-specific stable isotope markers based on soil vegetation cover were applied. Mixing model posterior distributions of proportional sediment source contributions differed when sources were pooled across the watersheds (pooled-MixSIAR) compared to those where source terms were stratified by sub-watershed and the outputs deconvoluted (D-MixSIAR). In the first example, the stratified source data and the deconvolutional approach provided greater distinction between pasture and cultivated topsoil source signatures resulting in a different posterior distribution to non-deconvolutional model (conventional approaches over-estimated the contribution of cultivated land to downstream sediment by 2 to 5 times). In the second example, the deconvolutional model elucidated a large input of sediment delivered from a small tributary resulting in differences in the reported contribution of a discrete mixed forest source. Overall D-MixSIAR model posterior distributions had lower (by ca 25–50%) uncertainty and quicker model run times. In both cases, the structured, deconvoluted output cohered more closely with field observations and local knowledge underpinning the need for closer attention to hierarchy in source and mixture terms in river basin source apportionment. Soil erosion and siltation challenge the energy-food-water-environment nexus. This new tool for source apportionment offers wider application across complex environmental systems affected by natural and human-induced change and the lessons learned are relevant to source apportionment applications in other disciplines.