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Item Extracellular enzymes from brown-rot fungus Laetiporus sulphureus isolated from mangrove forests of coastal Tanzania(2008) Mtui, Godliving; Masalu, RoseA brown-rot fungus, Laetiporus sulphureus (Fr.) Murr., was isolated from Mbweni, Oyster Bay and Mtoni Mangove Forests in Dar es Salaam, Tanzania, and the biochemical properties of its extracellular enzymes were investigated. The crude culture filtrate was concentrated by ultrafiltration. Protein content and lignocellololytic enzyme activities were measured by photometric methods. The crude enzyme extract was purified by gel chromatography and characterized by sodium docecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The fungal filtrate had maximum manganese peroxidase (MnP) of 2.5 U/mL and lignin peroxidase (LiP) of 1 U/mL, but showed no laccase (Lac) activity. The enzyme extracts were able to oxidize rhemazol brilliant blue-R (RBB-R) dye and phenol, and could remove up to 90% color from raw textile effluent in immobilized culture. The purified peroxidases showed that the MnP from S. sulphureus has a molecular weight of 48 kDA. The study elucidated the extracellular enzymes profile of facultative marine L. sulphureus and provided basic information on their potential for biological wastewater treatment systemsItem Lignocellulosic Enzymes from Flavodon Flavus, a Fungus Isolated from Western Indian Ocean off the Coast of Dar es Salaam, Tanzania(African Journal of Biotechnology, 2008-07-17) Mtui,Godliving; Nakamura, YoshitoshiMarine basidiomycetes fungus Flavodon flavus (Klotzsch) Ryvarden was isolated from sea grass at Mjimwema in the Western Indian Ocean off the Coast of Dar es Salaam, Tanzania, and cultured in the laboratory. Protein content and lignocellulosic enzyme activities were measured by photometric methods. Desalted and size-separated enzyme filtrates were resolved by sodium docecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing (IEF). The fungal filtrate had maximum lignin peroxidase (LiP), manganese peroxidase (MnP) and Laccase (Lac) activities of 42, 25 and 15 U/mL, respectively. At low carbon medium, F. flavus showed effective (92 - 100%) decolorization of raw textile wastewater and synthetic dyes such as rhemazol brilliant blue-R (RBB-R), Brilliant green, Congo red, Reactive black and Reactive yellow. SDS-PAGE analysis showed major bands of size separated enzymes from F. flavus at relative molecular weights between 45 and 70 kDa. The LiP of F. flavus, purified by ion exchange chromatography, revealed that it has a molecular weight of 46 kDa and isoelectric point (pI) of 3.8. The study confirmed extracellular enzymes from F. flavus to be potential degraders of organic pollutants and showed that facultative marine fungi that live under harsh seawater conditions are suitable for bioremediation of recalcitrant environmental pollutants.Item Forestland tenure systems in Tanzania: an overview of policy changes in relation to forest management(Norwegian University of Life Sciences, 2009-12-28) Eliakimu Zahabu; Tron Eid; George Kajembe; Lawrence Mbwambo; Cellina Mongo; Anthony Sangeda; Rogers Malimbwi; Josiah Katani; Japhet Kashaigili; Emmanuel LuogaA review of the role of forestland tenure systems in Tanzania, and how different forestland tenure approaches and reforms have influenced forest management is presented. The complexity of land reforms and processes that have taken place in Tanzania during the pre-colonial, colonial and post-independence periods is discussed. The pre-colonial period, though not much is written, was characterised by forest management through traditional institutions, low population and low forest resources exploitation. Colonial governments undermined the role of local traditions in managing the forests related to for example burial areas and springs. They also established forest reserves and in some areas cleared indigenous forests to establish tea, coffee and exotic fruit and timber plantations. Different land reforms that were geared towards sustainable development occurred after independence, forests depletion continued, however. Currently, it is observed that there coexists state, village, private and collective rights on forests without clear ownership. This is greatly linked to the ongoing deforestation and forest degradation in the country. In this situation, sustainable forestland use may be attained through establishing an enabling environment that allows effective local communities’ participation in forest management. Sustainable management, however, always presupposes effective control of harvesting and other activities to secure the carrying capacity of forests and woodlands, whether it is undertaken by central authorities or local people. Studies on forestland tenures and rights, and the impact of changes in tenures and rights on forest resources and rural livelihoods are therefore important. Such studies are required for the provision of facts for the establishment of proper future policy means that aim at reducing forest degradation and improving livelihoods in Tanzania.Item Optimization of Laccase and Manganese Peroxidase Production in Submerged Culture of Pleurotus Sajor - caju(African Journal of Biotechnology, 2011-07-08) Patrick ,Ferdinandi; Mtui, Godliving; Mshandete ,Anthony Manoni; Kivaisi, AmeliaA white-rot fungus, Pleurotus sajor-caju, was isolated from coastal Tanzania and screened for crude lignolytic enzymes production using rhemazol brilliant blue R (RBBR) dye, 2,2-azino-bis (3 ethylbenzthiazoline)-6-sulfonate (ABTS) and guaiacol in a semi-solid medium. Laccase (Lac) and manganese peroxidase (MnP) were detected by α αα α-napthol and pyrogallol solutions, respectively, on the guaiacol supplemented semi-solid media. The effect of temperature, pH, carbon, nitrogen, Cu2+, 2,5 xylidine, ferulic acid, Mn2+ and immobilization using Luffa cylindrica sponges in submerged culture fermentations were investigated for maximum enzymes production. After 7 days of incubation, 83 to 100% oxidation of RBBR, ABTS and guaiacol was observed. With optimized culture conditions, the fungal filtrate had maximum Lac and MnP activities of 80 and 0.94 U/ml, respectively compared to 0.62 and 0.0003 U/ml obtained with non-optimized ones; amounting to 129 and 3133 times increase in Lac and MnP activities, respectively. The improved crude enzymes activities, RBBR decolourization, ABTS and guaiacol oxidation capabilities of P. sajor-caju show its potential as a source of industrial enzymes for biotechnological applicationsItem Periodic Flooding and Land Use Effects on Soil Properties in Lake Victoria Basin(Academic Journals, 2011-09-19) Nancy Mungai W.; Njue A. M.; Abaya Samuel G.; Vuai Said A. H.; Ibembe John D.Frequent periodic flooding and land use changes taking place in the Lake Victoria basin (LVB) in east Africa may cause soil deterioration and further exacerbating food insecurity. Surface (0 to 20 cm) soil samples were collected at three locations along Sondu Miriu (Kenya) and Simiyu-Duma (Tanzania) rivers. Samples were collected from fields that were periodically flooded (1-28 d) and those that never flood, either under grass or crops. Samples were analysed for soil texture, organic carbon (OC), total nitrogen (TN), pH, extractable phosphorus (P), exchangeable potassium (K) and -glucosidase activities. -glucosidase activities, clay and P contents were higher in some of the soils that flood, while OC, exchangeable K and sand contents were lower at P< 0.05 in flooded soils. Observed differences account for 11% of comparisons in the two river basins. Soils under grass had higher -glucosidase activities and silt content but lower sand content than cultivated soils in 6% of samples in the two basins. However, conversion of natural ecosystems to grassland or cropped lands resulted in a 17 to 113% reduction in OC, TN, and exchangeable K in Sondu, and a 129% decline in TN in Simiyu. Soil properties exhibited clear but different patterns from upstream to downstream in the two basins. OC, TN, clay and -glucosidase activities were higher in Sondu upstream, while OC, TN, extractable P and exchangeable K were lower in Simiyu upstream. Observed difference across each basin underscore the importance of inherent soil characteristics in influencing soil properties compared to short-term flooding or short duration changes in land use.Item Quantifying Rooftop Rainwater Harvest Potential: Case of Mbeya University of Science and Technology in Mbeya Tanzania(Mbeya University of Science and Technology Journal of Research and Development (MJRD), 2013-07-21) Katambara, ZachariaThe advantages that the rooftop rainwater harvesting system has as a source of water supply have been examined. The observed daily rainfall records of 10 years and the current total roof area of the facilities at Mbeya University of Science and Technology as the catchment area were used. Using a water balance model to determine the suitable water use that will cover 100% of the time, the model indicated that for the current roof area a water supply of 120 lts per day can be met when a storage tank whose capacity is 13.5 m3 is installed. When values higher than 120 l/day are simulated, a tank of higher capacity is required to meet the water demand. The study recommends on the necessity of installing rooftop rainwater harvesting system so as to increase the water supply reliability and reduction of cost. The selection of a suitable storage tank capacity should take into consideration the future development plans so as to reduce the construction cost of new storage tank.Item Does Tanzania Social Action Fund Intervention a Panacea to Food Insecure Vulnerable Rural Poor People?(IJRSS, 2014-08) M, Mwidege Asheri; Mlambiti, M.E.; Damas, PDevelopment intervention is increasingly reported as a means of improving the livelihoods of the vulnerable poor people. However, little information on what could have been happened if there could be no intervention is available. This study was conducted to assess the livelihood impact of Tanzania Social Action Fund intervention in Agriculture for vulnerable communities in Makete and Rungwe Districts. This research examined whether intervention in food security is a panacea for the vulnerable communities. A quasi-experimental design was used to collect a sample of 239 and 115 recipient and non-recipient households and triangulation approaches were employed, respectively. Pairedt -test, chi-square test and phi-coefficient were used to ascertain the significance of the means of differences, comparing sample variance and strength of relationship between qualitative variables, respectively. Results showed that recipients were food insecure than non recipients. Based on these findings, it is concluded that intervention on food security through participation is not a panacea to vulnerable communities. Therefore, it is recommended that intervention should be on prevention basis rather than coping strategies.Item Characteristics of Rice Produced Under Direct and Indirect SRI Practices in Chimala Area in Mbarali District Tanzania.(Infinite, 2016) Katambara, Zacharia; Mng’ong’o, Marco; Chambi, Consolatha; Malley, ZachariaThe current status of rice production in Chimala Area in Mbarali is dominated by conventional rice growing practices with limited adoption of the system of rice intensification (SRI), which has been reported of having more advantages. This study evaluated the characteristic of rice produced under SRI and conventional practices in Chimala Area in Mbarali District of Mbeya Region in Tanzania. The evaluation considered the farm management practices, rice yields and the characteristic of the rice grains. The unlevelled characteristics of the farms and the variation of the soil influence the rice yields and the quality of the grains. The transplanting age of the seedling was within the age limit preferred when SRI practices are implemented and the limited water availability for conventional rice growing practice necessitated the intermittent wetting and drying of the rice fields which is preferred for SRI practices. The application of agrochemicals such herbicides limit the aeration of the root system and the development of a healthy roots system. Bird scaring is among the activities which increased the production cost of rice grown under SRI practices. Rice yields under SRI practices where more than 16ton/ha against less than 8ton/ha for conventional rice growing practices. The rice grains grown under SRI practices was observed to be suitable for seeds. With regard to milling, conventionally grown rice produced more good rice (69%) SRI (51%) grown. However, the large percentage of husks (24%) likely suggest that rice grains produced under SRI are more protected and further provide evidence as a good rice seed producing practice. The quality of cooked rice indicate that rice produced under SRI practices has higher aroma and fragrance when compared to that produced under conventional practices. Further studies should consider the effect of the number of seedling per hill, application of herbicide instead of applying push weeder and the suitability of using by-product, rice husks as a source of energy.Item Performance evaluation of rainwater harvesting system and strategy for dry season challenge(IWA Publisher, 2016) Mwamila, Tulinave Burton; Han, Moo Young; Ndomba, Preksedis Marco; Katambara, ZachariaThe extensive application of rainwater harvesting (RWH) projects is inhibited by the challenge posed by the dry seasons. In a case study of Mnyundo Primary School, Tanzania, the performance of the RWH system was eval- uated using a daily water balance model. The methodology is based on defined dry season parameters – no water days (NWDs), rainwater usage ratio (RUR), and water level in local water storages; while the system oper- ational methods involve users adopting either fixed (constant) demand or variable demand (demand varying with respect to available water in the storage tank), throughout the system utilization. Additionally, the cost of instal- ling an RWH system to achieve a substantial reduction of NWDs to zero was calculated. It was established that the existing system cannot achieve zero NWDs under consideration of both operational methods. However, the greater the number of tanks, the lower the NWD, and in the variable demand operational method, better RUR was achieved. For mitigating water shortages in the dry season, the school should adopt RWH in two buildings under the demand scenario (300 demand 900 L/d, for the respective water levels in the storage tanks), yielding 58% RUR. The performance of the system can be improved by monitoring water levels and adhering to demand guide- lines. These are useful strategies for practitioners in water supply.Item Aflatoxins and Fumonisin Contamination of Marketed Maize, Maize Bran and Maize Used as Animal Feed in Northern Tanzania.(AFRICAN SCHOLARLY SCIENCE COMMUNICATIONS TRUST, 2016-07) Nyangi Chacha; Mugula J.K; Beed F.; Boni S.; Koyano E.; Sulyok, M.The objective of this study was to investigate the occurrence of total aflatoxin and total fumonisin in maize and maize-based products in Babati, northern Tanzania. A total of 160 samples were collected in 2013-14. Quantification for total aflatoxin and fumonisin was done using enzyme-linked immunosorbent assay (Reveal AccuScan® Neogen, USA) and the results were confirmed using Liquid Chromatography Tandem Mass Spectrometer. Aflatoxin was detected in 32% of maize samples (mean 3.4 ± 0.3 µg/kg; range 2.1–16.2 µg/kg) and fumonisin in 39% of samples (mean 5.6 ± 1.40 mg/kg; range 0.4–62.0 mg/kg). Among marketed products, maize bran (used for animal feed) was the most contaminated (2.4 µg/kg aflatoxin and 1 mg/kg fumonisin), followed by whole maize in market stalls (1.9 µg/kg aflatoxin and 0.4 mg/kg fumonisin) and then maize flour (1.4 µg/kg aflatoxin and 0.3 mg/kg fumonisin). Un-marketed maize sorted out by farmers as “bad” and intended for animal feeding was the most contaminated (overall mean aflatoxin and fumonisin levels of 1.7 µg/kg and 7.4 mg/kg, respectively). The results indicate that levels of aflatoxin and fumonisin contamination in marketed maize were within tolerable limits.Item ASSESSMENT OF PRE-HARVEST AFLATOXIN AND FUMONISIN CONTAMINATION OF MAIZE IN BABATI DISTRICT, TANZANIA(AFRICAN SCHOLARY SCIENCE TRUST, 2016-07) NYANGI, C; BEED, FA survey was conducted in 2013 to establish total aflatoxin and total fumonisin in maize, as well as farmers’ practices relating to maize cultivation and awareness of mycotoxins, in three villages of Babati District, northern Tanzania. Quantification of total aflatoxin and fumonisin was done using enzyme-linked immunosorbent assay (Reveal AccuScan® Neogen, USA) and the results were confirmed using Liquid Chromatography Tandem Mass Spectrometer. The mean aflatoxin was 2.94 µg/kg and all samples (n=440) were within the East African Community (EAC) standard of 10 µg/kg for total aflatoxin, but the mean fumonisin was 5.15 mg/kg, more than double the EAC standard of 2 mg/kg, and 35% of samples exceeded this standard. Maize samples obtained from farmers in the village in the mid altitude, dry zone had significantly higher mean aflatoxin (3.32 µg/kg) and significantly lower mean fumonisin (3.17 mg/kg) than maize from the other two villages (in the high and mid altitude, high rainfall zones). Most farmers (n=442) were male (72%), educated to primary school level (77%) and aware of mycotoxins (62%). As well as participating in a development program, Africa Research in Sustainable Intensification for the Next Generation, most (86%) farmers had experience of working with other development programs. All farmers used flat planting, most used improved seeds (98%), ox ploughing (78%), insecticides (78%) and early planting (36%). Practices associated with mycotoxins were planting time, tillage methods, previous season planted crops, and use of insecticides. Awareness of mycotoxins and climatic conditions were also associated with mycotoxin prevalence. In conclusion, good practices are associated with acceptable aflatoxin levels and should be continued. However, the high level of fumonisins warrants further investigation.Item Strategy to Overcome Barriers of Rainwater Harvesting, Case Study Tanzania(Scientific Research Publishing, 2016-09-12) Burton, Mwamila Tulinave; Young, Han Moo; Katambara, ZachariaThere are Socio-Technological Challenges Towards Extension of The Application of Rainwater Harvesting (RWH) Practicesin Developing Countries. an Attempt to Ad- Dress this was Done Using the Mnyundo Primary School, Tanzania, as A Study Area For Evaluating the Technical, Economic, and Social Challenges of RWH Practices. A Sto- Rage Water Level Monitoring Gauge was Used so as to Simplify Rainwater Quantity Con- Trol and Utilization Strategy. Basic Quality Control Components Such as First Flush Tank Were Incorporated so as to Reduce the Particle Load Flowing Into The Storage. Cost Re- Duction Strategies Such As The One (1) Company One (1) Community Campaign Were Applied To Address The Cost Implication. To Enhance Ownership, Participatory Ap- Proach Of The Beneficiaries In All Stages Including Planning, Designing And Imple- Mentation Was Adopted. In Order To Ensure Project Sustainability, Training On How To Operate And Maintain Were Provided As Well As A Maintenance Manual To Impart A Sense Of Ownership. For The Challenges Of Imparting RWH Practices In Tanzania, 19 Solutions Have Been Identified And They Include Provision Of RWH Manuals, Guide- Lines And Regulations, Government Incentives, And Promotion Of Self-Financing Initia- Tives. For Developing Countries, The Study Proposes The Following Strategies: Estab- Lishing Relevant Regulations And Research Centers, Enhancing Individual And Commu- Nity Financial Stability, Conducting Demonstration Projects, And Increased Investment By Government On Promotion. PrivateItem Aflatoxin and Fumonisin Contamination of at-harvest and Storage Beans in Babati District, Northern Tanzania(Greener Journal of Agricultural Sciences, 2016-11) NYANGI,CHACHAThe natural occurrence of total aflatoxin and fumonisin was determined in 38 bean at-harvest samples and 106 storage beans samples in the year 2013 in Babati District Northern Tanzania. Quantification for total aflatoxin and fumonisin was done using Enzymes Linked Immunosorbent Assay - ELISA (Reveal AccuScan® Neogen, USA), and the results were confirmed using Liquid Chromatography Tandem Mass Spectrometer (LC-MS/MS). Eighteen percent (7/38) of bean at harvest samples were contaminated with up to 3 µg/kg aflatoxins and no bean sample was contaminated with fumonisins. There was a significant correlation (p < 0.05) between the concentration of aflatoxins and fumonisins with climatic zones and agronomic practices. Only bean samples from the high-altitude high rain zone were contaminated with aflatoxins (mean level of 1.53 µg/kg). For storage beans, samples from Seloto village were associated with higher aflatoxin concentration (mean of 3.74 µg/kg) and those from long village were associated with higher fumonisin levels (mean of 9.0 mg/kg). These results indicate that beans consumers in the study area are exposed to the danger of chronic exposure to aflatoxin and fumonisin poisoning. Thus, those practices that reduce contamination should be adopted by all farmers in the study area to reduce the health hazards associated with consumption of contaminated beans. This also calls for further research to investigate human exposure to aflatoxin and fumonisin in the study area.Item Integrated Agricultural Landscape Management: Case Study on Inclusive Innovation Processes, Monitoring and Evaluation in The Mbeya Region, Tanzania.(SAGE, 2017-06-08) Malley, Zacharia J.; Hart, Abigail; Buck, Louise; Mwambene, Pius L.; Katambara, Zacharia; Mng’ong’o, Marco; Chambi, ConsolathaIntegrated landscape management is a process for achieving multiple objectives related to agricultural production, ecosystem conservation, and sustainable natural resource management. These multiple livelihood functions are important features of an agricultural landscape in Mbeya, Tanzania. Due to environmental damage caused by agricultural expansion and charcoal burning, a process called integrated agricultural landscape management (IALM) was implemented to address this problem. This encompassed the identification and involvement of a range of key landscape actors and processes like awareness creation and joint problem analysis, solution framing, learning, planning and implementation of actions, and monitoring and evaluation. A multistakeholder innovation platform was formed for creating a coordination mechanism, common understanding, vision and goals, and networking. Fifty IALM ideas were identified and six selected by the stakeholders. Outcomes of using the IALM process included policy recommendations, joint learning, and innovative actions and were codeveloped, implemented, monitored, and evaluated with the local communities.Item Harvest and Postharvest Factors Affecting Bruise Damage of Fresh Fruits(CSHS, 2019) Hussein, Zaharan; Fawole, Olaniyi A.; Opara, Umezuruike L.Fresh fruits are susceptible to bruising, a common type of mechanical damage during harvest and at all stages of postharvest handling. In quest of developing and adoption of strategies to reduce bruise damage, it is of utmost importance to understand major factors influencing bruise susceptibility of fresh produce at these stages. This review presents a critical discussion of factors affecting bruising during harvest and postharvest handling of fresh fruits. Excessive compression forces during harvesting by handpicking or machines, and a series of impacts during harvesting, transport and packhouse operations can cause severe bruise damage. The review has further revealed that bruising is dependent on a number of other factors such as produce maturity, ripening, harvest time (during the day or season) and time lapse after harvest. The susceptibility to bruising is partly dependent on how these factors alter the produce physiological and biochemical properties, and the environ- mental conditions such as temperature, humidity and several other postharvest treatments. Hence, the successful applications of harvesting techniques by use of trained personnel and proper harvesting equipment are essential to reduce both the incidence and severity of bruising. Furthermore, the careful selection of postharvest handling temperature and other treatments can increase resistance of fresh produce to bruise damage.Item Effect of Chia Seeds (Salvia Hispanica) on Postprandial Glycaemia, Body Weight and Hematological Parameters in Rats Fed A High Fat and Fructose Diet(IFG, 2020) Mihafu, Fabian D.; Kiage, Beatrice N.; Kimang’a, Andrew N.; Okoth, Judith K.Chia seeds (Salvia hispanica) are currently consumed by varied populations as superfoods due to their protective, functional and antioxidant properties. The aim of this study was to determine the effect of ground chia seeds/extracts on postprandial glycaemia, body weight, hematological parameters and cellular morphology in rats. Twenty male Wistar rats were assigned into three experimental groups and a control (n =5). Each experimental group received 10 g/20 g fructose/lard. Additionally, 90 g rat pellet was fed to group 1 and 3 which was supplemented with 20 g chia seed extract, group 2 received ground chia seeds only. Control group received 90 g rat pellet only for 28 days. The results on body weight changes indicated a gradual increase in body weight of chia seeds/extract fed rats as compared to fructose/lard group. There was an increase in postprandial blood glucose levels in group 1 from week I to IV contrary to groups supplemented with chia seeds/extract. Complete blood counts showed a significant increase (p = 0.008) in mean corpuscular hemoglobin concentration, basophils (p = 0.035), platelets (p = 0.025) and red cell distribution width (p = 0.008) in experimental groups compared to control. These results pinpoint the benefits of chia seedsItem Challenges and Opportunities Toward Sustainable Consumption and Value Addition of Cashew Apples in Tanzania(SAGE, 2020) Dimoso, Noel; Aluko, Angela; Makule, Edna; Kassim, NeemaCashew apple is an important healthy fruit due to its high nutrient contents, particularly vitamin C. However, its full potential is yet to be realized in low technological countries. This paper explores farmers’ consumption habits, processing methods, and utilization constraints faced. Also, osmotic-solar dried product was developed. In an exploratory survey, 600 farmers across the surveyed districts were interviewed. The study revealed that the majority of farmers consume raw cashew apples, with 61.9% consuming more than five fruits a day and about 56.0% consuming almost every day during the season. About 43.7% of farmers traditionally process cashew apple porridge and alcohol. Lack of knowledge on post harvest handling (86.2%), and processing technologies (82.7%) were mostly claimed to hamper the utilization. The developed dried products retained 59.4% of total acidity, 37.4% of total ascorbic acid, and 68.5% tannins. In addition, the product received better sensory scores and overall acceptability. Though solar drying relies heavily on weather condi tions, where possible it could be a better alternative to traditional methods. The combination of blanching, osmotic dehydration and solar drying could provide economically feasible value added products to both urban and rural settings and ultimately reduce the post-harvest losses and unleash their economic potentialItem Climate change mitigation through carbon dioxide (CO2) sequestration in community reserved forests of northwest Tanzania(Agriculture and Environmental Science Academy, 2020) Malunguja, Gisandu K.; Devi, Ashalata; Kilonzo, Mhuji; Rubanza, Chrispinus D.K.Forests play a key role in climate change mitigation through sequestering and storing carbon dioxide from the atmosphere. However, there is inadequate information about carbon accumulation and sequestered by community reserved forests in Tanzania. A study was carried to quantify the amount of carbon sequestered in two forests namely; Nyasamba and Bubinza of Kishapu district, northwestern Tanzania. A ground-based field survey design under a systematic sampling technique was adopted. A total of 45 circular plots (15 m radius) along transects were established. The distances between transect and plots were maintained at 550 and 300 m, respectively. Data on herbaceous C stocking potential was determined using destructive harvest method while tree carbon stocking was estimated by allometric equations. The collected data were organized on excel datasheet followed by descriptive analysis for quantitative information using Computer Microsoft Excel and SPSS software version 20, while soil samples were analyzed based on the standard laboratory procedures. Results revealed higher carbon sequestration of 102.49±39.87 and 117.52±10.27 for soil pools than plants both herbaceous (3.01±1.12 and 6.27±3.79 t CO2e/yr) and trees (5.70±3.15 and 6.60±2.88 t CO2e/yr) for Nyasamba and Bubinza respectively. The study recorded a potential variation of soil carbon sequestration, which varied across depths category (P < 0.05). However, there was no difference across sites (P >0.05) and species (P > 0.05) for herbaceous and trees. The findings of this study portrayed a significantly low value for carbon stocking and sequestration potential for enhanced climate change mitigation. Therefore, proper management of community reserved forest is required to accumulate more C for enhancing stocking potential hence climate change mitigation through CO2 sequestration offsets mechanism.Item An Assessment of the Current Status and Regeneration Potential of the Traditional Conserved Forests (Ngitili) in Kishapu District, Tanzania(TROPICAL PLANT RESEARCH, 2020) Malunguja, Gisandu K.; Rubanza, Chrispinus K. D.; Devi, AshalataThe current study was carried out in the community forests conserved under the indigenous knowledge known as “Ngitili” in Kishapu district of Tanzania. The aim was to assess the current status and determines its regeneration potential in terms of plant species diversity, herbaceous productivity and tree stocking. A field survey was conducted for recording the current status while the phytosociological was carried to recognize vegetation composition and diversity. Regeneration potential was determined based on the population size of seedlings, saplings and adults. Disturbance index was used to calculate the level of disturbances while herbaceous productivity and tree stocking were estimated based on allometric models. Descriptive statistics for quantitative data was analysed using SPSS version 20. The study recorded a total of 10 Ngitili in Kishapu district, out of which, 9 still existing but highly threatened and disturbed, only 1 Ngitili was recorded to be dead (not existing). A total of 66 plant species were recorded of which 20 were grasses, 18 were forbs, and 28 species (17 genera and 13 families) were trees and shrubs. The dominant grass species were Aristida funiculata (28.9%) and Cynodon dactylon, while Monechma debile (4.6%) was the dominant forb. Similarly, Acacia drepanolobium (45.4) and Balanites aegyptiaca (42.9) trees dominated the area. The majority of tree species exhibited a “not regenerating” condition (51.8%) only a few (2.11%) showed a “good regeneration” condition while “newly regeneration” condition recorded 0.00%, with a diversity ranging from 1.86–2.44. Herbaceous and tree stocking potential was 1.23±0.05 t DM ha-1 and 5.66±0.21 t Cha-1 respectively, with a standing stem density (stems ha-1) of 512.07±193.86. The study observed great degradation of the Ngitili characterized by low diversity and poor regeneration conditions. This signified that these community forests are currently threatened and its sustainability is highly at risk unless strong initiatives take place.Item Experimental evaluation of drying of banana using a double-pass solar collector (DPSC) and theoretical analysis using a CFD model(TAYLOR & FRANCIS, 2020-07-13) Mutabilwa, Philemon X.; Nwaigwe, Kevin N.Preservation of banana through drying is a recommended method for improving the shelf life. In this study, an experimental and theoretical evaluation of a developed forced-convection indirect solar drying system with a double-pass solar collector (DPSC) was undertaken. Experimentation using banana slices of 4 mm thickness was carried out. The DPSC achieved an optimal peak outlet temperature of 72°C with a maximum operational efficiency of 72.5%. A computational fluid dynamic (CFD) model was developed for prediction of the dryer temperature and 3D airflow distribution within the dryer unit using ANSYS 18.2. The CFD model was validated using experimental data and good agreement was achieved. The devel oped dryer demonstrated improved efficiency over similar dryers, and this is attri butable to the unique arrangement of component parts. Dried banana chips were evaluated for quality through taste, color and shape and the results indicated good quality products. This was attributed to the pretreatment of banana chips with lemon juice prior to drying.
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