Browsing by Author "Mbilinyi, B. P."

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Comparative assessment of soil and nutrient losses from three land uses in the central highlands of Ethiopia
(Academic journals) Jaleta, D.; Mbilinyi, B. P.; Mahoo, H. F.; Lemenih, M.
Comparative assessment of soil and nutrient losses from three land uses in the central highlands of Ethiopia
(Academic journals, 2017) Jaleta, D.; Mbilinyi, B. P.; Mahoo, H. F.; Lemenih, M.
Land use/land cover change drive changes in several ecosystem processes over short and long terms. In Ethiopia, the main land use/land cover change involves conversion of natural ecosystem into cultivated land. However, a recent change also involves conversion of cultivated and gra zing land into Eucalyptus woodlots. This study was conducted to analyse the effects of such land use/land cover change on soil and nutrient losses. Three land use/ land cove r types (cultivated land, grassland and Eucalyptus woodlot) were selected for a comparative assessment. A total of twelve runoff plots, each with 43.3 m2 area and with four replications, were installed. Rainfall depth, runoff volume and sediment samples (500 ml) were collected from each plots every morning and evening for 91 days (from 4th July to 2nd October, 2015) in the main rainy season. The sediment samples for ten consecutive days were stored in separate containers and composite sediment concentration samples were weighed after being filtered and oven dried for 24 hours at 105o c. From the samples taken at the end of the rainy season, separate composite a sample before filtration of one litre was analysed in the laboratory for nutrient losses. The effect of land use/land cover on soil and nutrients losses was statistically tested using analysis of variance. The study found that soil loss significantly differed between the land use /land cover types. Soil loss from cultivated land (16.8 ton/ha) was significantly higher than loss from grassland (7 ton/ha) and Eucalyptus stand (8.1 ton/ha). The soil and nutrient losses were positively correlated with runoff volume. There was higher nutrient (N and P) loss from cultivated land than grassland and Eucalyptus. From the results, it can be concluded that soil and nutrients losses are above tolerable limit, and perennial land covers including Eucalyptus stand reduce soil and nutrient losses significantly. This re-affirms the multi-purpose nature of Eucalyptus not only for socioeconomic benefit but also for soil erosion control when planted in appropriate locations
Deforestation and CO 2 emissions in coastal Tanzania from 1990 to 2007
(Foundation for Environmental Conservation) Godoy, F. L.; Tabor, K.; Burgess, N. D.; Mbilinyi, B. P.; Kashaigili, J. P.; Steininger, M. K.
Forest and woodland cover and change in coastal Tanzania and Kenya, 1990 to 2000
(Nature Kenya/East African Natural History Society) Tabor, K.; Burgess, N. D.; Mbilinyi, B. P.; Kashaigili, J. J.; Steininger, M. K.
Forest and woodland cover and change in coastal Tanzania and Kenya, 1990 to 2000
(Nature Kenya/East African Natural History Society, 2010) Tabor, K.; Burgess, N. D.; Mbilinyi, B. P.; Kashaigili, J. J.; Steininger, M. K.
Forest and woodland cover and change were calculated for the Zanzibar-Inhambane biogeographical region of Tanzania and Kenya from ~1990 to ~2000. A cover and change map was derived from high-resolution satellite imagery from Landsat and supplemental data from aerial overflights, field surveys, and local knowledge. Analyses showed that around 6820 km2 of coastal forest habitat remained in ~2000 (2260 km2 in Kenya and 4560 km2 in Tanzania). In terms of change, a total of 424 km2 (6%) of forest was cleared between ~1990 and ~2000; 53 km2 in Kenya and 371 km2 in Tanzania. Rates of forest loss were 8 times higher in unprotected areas than in protected sites such as Forest Reserves and National Parks. Key Biodiversity Areas had forest loss rates 2.5 times faster than protected areas while Alliance for Zero Extinction sites had the slowest rates of forest loss for the region. These baseline forest cover and change estimates along with future updates can contribute to national and sub-national carbon emission baselines and assessments of species threat within the global Red List.
GIS-based decision support system for identifying potential sites for rainwater harvesting
(Physics and Chemistry of the Earth) Mbilinyi, B. P.; Tumbo, S. D.; Mahoo, H. F.; Mkiramwinyi, F. O.
GIS-based decision support system for identifying potential sites for rainwater harvesting
(Physics and Chemistry of the Earth, 2007) Mbilinyi, B. P.; Tumbo, S. D.; Mahoo, H. F.; Mkiramwinyi, F. O.
Identification of potential sites for rainwater harvesting (RWH) is an important step towards maximizing water availability and land productivity in the semi-arid areas. However, selection of appropriate sites for different RWH technologies on a large scale presents a great challenge, since the necessary biophysical data and infrastructure are often lacking. This paper presents a geographic information system (GIS)-based decision support system (DSS) that uses remote sensing (RS), limited field survey to identify potential sites for RWH technologies. The input into the DSS include maps of rainfall, slope, soil texture, soil depth, drainage and land use/cover and the outputs are maps showing potential sites of water storage systems (ndiva), stone terraces, bench terraces and borders. The Model Builder in the Arc View GIS was used as a platform for the DSS. Two sites in the Makanya watershed, in Kilimanjaro Region, Tanzania, were used for testing and validation of the DSS. The results reflect specific suitability levels of parameters and weight of factors; for example, near streams (drainage) with slope ranges from moderately steep to steep (10 –30 ) are potential sites for ndiva locations whereas moderately undulating to steep slopes (5 –30 ) with unstable soils are potential sites for stone terraces. Moderately undulating slopes (5 –10 ) with clay, silt clay and sandy clay soils are potential sites for bench terrace and gently undulating slopes (2 –5 ) with clay, silt clay and sandy clay soils are potential sites for borders. The results from testing and validation of the developed DSS indicated that the tool can be used reliably to predict potential sites for RWH technologies in semi-arid areas. Most of predicted RWH technologies during testing were found within very highly and highly suitable locations (41.4% and 40%, respectively) also in validation 36.9% of RWH technologies were found within the moderately suitable followed by very highly suitable and highly suitable both with 23.6%. Despite the good results, it is recommended that more work be carried out to refine the model and to include other pertinent ancillary data like socio-economic factors to increase its usefulness.
Identification of suitable indices for identification of potential sites for rainwater harvesting
Tumbo, S.D.; Mbilinyi, B. P.; Mahoo, H. F.; Mkilamwinyi, F.O.
Impact of projected climate change on agricultural production in semi-arid areas of Tanzania: A case of Same district
Tumbo, S. D.; Kahimba, F. C.; Mbilinyi, B. P.; Rwehumbiza, F. B.; Mahoo, H. F.; Mbungu, W. B.; Enfors, E.
Integrated assessment of forest cover change and above-ground carbon stock in Pugu and Kazimzumbwi forest reserves, Tanzania
(SciRes) Kashaigili, J. J.; Mdemu, M. V.; Nduganda, A. R.; Mbilinyi, B. P.
Mapping Socio-Economic Scenarios of Land Cover Change: A GIS Method to Enable Ecosystem Service Modelling
(Elsevier) Swetnam, R. D.; Fisher, B.; Mbilinyi, B. P.; Munishi, P. K. T.; Willcock, S.; Ricketts, T.; Mwakalila, S.; Balmford, A.; Burgess, Neil D.; Marshall, A. R.; Lewis, S. L.
Two decades of change in state, pressure and conservation responses in the coastal forest biodiversity hotspot of Tanzania
(Cambridge CB3 0DL, UK) Burgess, N. D.; Malugu, I.; Sumbi, P.; Kashindye, A.; Kijazi, A.; Tabor, K.; Mbilinyi, B. P.; Kashaigili, J. J.; Wright, T. M.; Gereau, R. E.; Coad, L.; Knights, K.; Carr, J.; Jeahrends, A.; Newh, R. L.
Two decades of change in state, pressure and conservation responses in the coastal forest biodiversity hotspot of Tanzania
(Cambridge CB3 0DL, UK, 2016) Burgess, N. D.; Malugu, I.; Sumbi, P.; Kashindye, A.; Kijazi, A.; Tabor, K.; Mbilinyi, B. P.; Kashaigili, J. J.; Wright, T. M.; Gereau, R. E.; Coad, L.; Knights, K.; Carr, J.; Jeahrends, A.; Newh, R. L.
We present an analysis of changes of state, pres- sures and conservation responses over 20 years in the Tanzanian portion of the Coastal Forests of Eastern Africa biodiversity hotspot. Baseline data collected during 1989-1995 are compared with data from a synthesis of recently published papers and reports and new field work carried out across the region during 2010-2014. We show that bio- diversity endemism values are largely unchanged, although two new species (amphibian and mammal) have been named and two extremely rare tree species have been relo- cated. However, forest habitat continues to be lost and de- graded, largely as a result of agricultural expansion, charcoal production to supply cities with cooking fuel, log- ging for timber and cutting of wood for firewood and build- ing poles. Habitat loss is linked to an increase in the number of species threatened over time. The government-managed forest reserve network has expanded slightly but has low ef- fectiveness. Three forest reserves have been upgraded to National Parks and Nature Reserves, which have stricter protection and more effective enforcement. There has also been rapid development of village-owned forest reserves, with more than 140 now existing; although usually small, they are an important addition to the areas being managed for sustainable resource use, and also provide tangible benefits to local people. Human-use pressures remain in- tense in many areas, and combined with emerging pressures from mining, gas and oil exploration, many endemic species remain threatened with extinction.
Unmanned aerial vehicle-based remote sensing in monitoring smallholder, heterogeneous crop fields in Tanzania
(International journal of remote sensing) Yonah, I. B.; Mourice, S. K.; Tumbo, S. D.; Mbilinyi, B. P.; Dempewolf, J.
Unmanned aerial vehicle-based remote sensing in monitoring smallholder, heterogeneous crop fields in Tanzania
(International journal of remote sensing, 2018) Yonah, I. B.; Mourice, S. K.; Tumbo, S. D.; Mbilinyi, B. P.; Dempewolf, J.
Obtaining information to characterize smallholder farm fields remains elusive and has undermined efforts to determine crop conditions for food security monitoring. We hypothesize that unmanned aerial vehicles (UAV) would provide high-resolution spectral signatures for effectively discerning agronomic and crop conditions, management practices, and yields in smallholder farms for crop yield outlooks. The current study explores potential in using UAV-mounted sensor spectral signatures for monitoring crop conditions in smallholder agriculture. Images were collected using a 4-band multispectral camera mounted on a small fixed wing UAV, flown at 8-day interval over maize–pigeonpea experimental plots at Sokoine University of Agriculture and maize monocrop in farmers’ fields nearby, during 2015/2016 growing season. Four spectral vegetation indices (VIs) namely; normalized difference vegetation index (NDVI), wide dynamic range vegetation index (WDRVI), red edge chlorophyll index (CIred-edge), and the green chlorophyll index (CIgreen), were evaluated under maize monocrop, maize pigeonpea-intercrop, fertilizer and non-fertilizer and two maize varieties conditions. VIs were used also to detect differences in farm management practices of two farmers’ maize fields. The response of the spectral VIs varied depending on phenological stage of the crop and imposed treatments or management practices. In experimental plots, NDVI was able to distinguish fertilized from non-fertilized plots at all times, distinguish between two maize varieties at 52 days after sowing (DAS), and differentiate monocropped maize from maize–pigeonpea intercrop at 60 DAS. CIred-edge could detect effect of maize–pigeonpea intercrop and maize varieties at 44 DAS, whereas CIgreen could detect variety differences at 44 DAS, intercropping effect at all times and fertilizer effects at 60 and 68 DAS. WDRVI could only detect variety differences and maize–pigeonpea intercrop at 44 DAS. Moreover, NDVI was slightly associated with maize yield in non-fertilized plots (coefficient of determination – R2 = 0.58) and CIgreen was associated with leaf area index (LAI) (R2 = 0.62) in fertilized plots and in monocropped plots (R2 = 0.61). CIgreen could also differentiate well managed from poorly managed farmer’s fields. We conclude that UAV-derived spectral signatures can provide detailed information for characterizing agronomic and crop conditions under smallholder agricultural settings and aid food security monitoring efforts.