Sustainable Agriculture

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16S Rrna Gene Amplicon-Based Metagenomic Analysis of Bacterial Communities in the Rhizospheres of Selected Mangrove Species from Mida Creek and Gazi Bay, Kenya
(PLOS ONE, 2021-03-23) Muwawa Edith M.; Obieze Chinedu C.; Makonde Huxley M.; Jefwa Joyce M.; Kahindi James H. P.; Khasa Damase P.
Prokaryotic communities play key roles in biogeochemical transformation and cycling of nutrients in the productive mangrove ecosystem. In this study, the vertical distribution of rhizosphere bacteria was evaluated by profiling the bacterial diversity and community structure in the rhizospheres of four mangrove species (Sonneratia alba, Rhizophora mucronata, Ceriops tagal and Avicennia marina) from Mida Creek and Gazi Bay, Kenya, using DNA-metabarcoding. Alpha diversity was not significantly different between sites, but, significantly higher in the rhizospheres of S. alba and R. mucronata in Gazi Bay than in Mida Creek. Chemical parameters of the mangrove sediments significantly correlated inversely with alpha diversity metrics. The bacterial community structure was significantly differentiated by geographical location, mangrove species and sampling depth, however, differences in mangrove species and sediment chemical parameters explained more the variation in bacterial community structure. Proteobacteria (mainly Deltaproteobacteria and Gammaproteobacteria) was the dominant phylum while the families Desulfobacteraceae, Pirellulaceae and Syntrophobacteraceae were dominant in both study sites and across all mangrove species. Constrained redundancy analysis indicated that calcium, potassium, magnesium, electrical conductivity, pH, nitrogen, sodium, carbon and salinity contributed significantly to the species–environment relationship. Predicted functional profiling using PICRUSt2 revealed that pathways for sulfur and carbon metabolism were significantly enriched in Gazi Bay than Mida Creek. Overall, the results indicate that bacterial community composition and their potential function are influenced by mangrove species and a fluctuating influx of nutrients in the mangrove ecosystems of Gazi Bay and Mida Creek.
A Soil Tool Kit to Evaluate Soil Properties and Monitor Soil Health Changes in Smallholder Farming Contexts
(Elsevier Publishing Company, 2020-10-15) Nyamasoka-Magonziwa Blessing; Vanek Steven J.; Ojiem John O.; Fonte Steven J.
Smallholder farmers often face challenges in managing soil fertility due to limited inputs and high spatial variability on their farms. While improved knowledge of soil constraints could help them manage limited resources more effectively, formal soil analyses are typically out of reach due to high costs of testing and transport associated with regional analytical laboratories. To address these challenges, we assembled a tool kit that uses minimal reagents and low-cost equipment to provide in-field quantitative data that are comparable to formal laboratory methods. We validated our tool kit measurements against standard analyses conducted at national laboratories on soils collected from 36 smallholder farms in Kenya and 115 farms in Peru. Additionally, in Kenya, we evaluated two legume treatments, involving the incorporation of residues from: 1) Lablab purpureus (lablab), versus 2) Phaseolus vulgaris (common bean). The tool kit measurements that were considered include important indicators of soil health (such as permanganate oxidizable carbon (POXC), available P, pH, particulate organic matter (POM), and aggregate stability) that can influence crop yields and multiple soil functions. POXC and pH measured with the tool kit from Kenyan soils were highly correlated to those measured by a standard laboratory (R2 = 0.77; R2 = 0.56; respectively). The tool kit and standard laboratory available P were less well correlated, but also showed a highly significant positive relationship (R2 = 0.30). Similar patterns were noted for POXC, pH and available P measured in Peruvian soils (R2 = 0.75; R2 = 0.75; R2 = 0.35; respectively). Importantly, the tool kit and standard lab analyses also displayed similar abilities to predict maize grain yield in Kenya. When used to detect soil impacts of incorporating P. vulgaris versus L. purpureus, only POM differed significantly between the two legume treatments, although L. purpureus was slightly higher for most of the beneficial soil health properties. Our findings suggest that the tool kit methods proposed here have broad applicability to smallholder farms for explaining variability in crop yields, assessing soil contexts, and quantifying management-induced changes in soil health.
Adaptive Capacity to Climate Change among Smallholder Farmers’ in Busia County, Kenya
(IOSR Journal of Agriculture and Veterinary Science, 2017-11-30) Agnes Mugure Sorre; Alice Kurgat; Richard Musebe; Benard Sorre
This paper emanates from a study that was carried out to assess smallholder farmers’ adaptive capacity to climate change effects in Busia County. Qualitative and quantitative data was collected from 376 respondents selected using multistage and simple random sampling techniques. Six determinants (financial, social, knowledge and information, institutions and flexible decision making) of adaptive capacity to climate change were assessed using a five point Likert scale. Findings indicated a moderate (2.65) adaptive capacity among smallholder farmers in Busia County. Low adaptive capacity was indicated in financial/economic resources (2.4), but moderate in knowledge/information (2.5), social (2.8), technology and innovation (2.7), institutional (2.8) and informed farming decision making resources. Therefore, low financial and economic resources limit ability to plan, prepare for, facilitate and implement adaptation measures. This paper recommends that development and climate change efforts should focus on climate change awareness and diversification for both on-farm and off-farm livelihood activities.
Adoption and Implementation of Devolved Farm Forestry Extension Services from Kenya Forest Service to County Governments: Socio-Economic Wellbeing of Rural Communities and Experiences from Homabay County, Kenya
(East African Nature and Science Organization, 2022-01-31) Ojijo, Akoth Lucy; Kipkosgei, Sirmah Peter; Kibiwot, Matonyei Thomas
In Kenya, all forestry functions were National Government affairs until 2013 when farm forestry extension was devolved to the 47 Counties, Homabay County being one of them. However, the adoption and extent of implementation of the devolved farm forestry extension services are little known and its impact on rural livelihoods has not been effectively established as well as the implementation of the Transition Implementation Plan by the County Government of Homabay is not evident. Structured questionnaires were administered purposively to 399 respondents spread in eight Sub-Counties of Homabay to gather data on the extent of implementation of the devolved farm forestry extension services, to evaluate socio-economic effects of farm forestry extension services to rural communities and the extent of adoption of devolved farm forestry extension services. Results indicate the extent of adoption of farm forestry extension services is low with the farmers expressing that as much as it’s a devolved function, it is not an active process within the rural communities (82%). The key socio-economic factors that affect the adoption and implementation of devolved farm forestry are; farmers level of income for purchase of tree seeds (61%), market availability for tree seedlings (44%), land sizes and tenure systems (68%). The extent of implementation was influenced by County Government budget allocation and prioritization (67%), availability of qualified personnel (81%), government policies on interactions between the two levels of governments (49%) and obligation to the Transition Implementation Plan (89%). The results suggest that County Government needs to prioritize budget allocation and have adequate personnel as means to adequately implement the devolved functions and also to implement the Transition Implementation Plan as laid down by the Kenya Forest Service.
Adoption, constraints and economic returns of paddy rice under the system of rice intensification in Mwea, Kenya
(Elsevier, 2013-11-01) Ndiiri, J. A.; Mati, B. M.; Home, P. G.; Odongo, B.; Uphoff, N.
A detailed farm survey was conducted in Mwea Irrigation Scheme, Kenya during the 2010/2011 and 2011/2012 main growing seasons to assess the adoption and to quantify the net income advantages of using system of rice intensification (SRI) management over farmer practices (FP) for rice cultivation. Data were collected through questionnaires and structured interviews with farmers who were practicing both SRI and FP methods of rice production on their farms. Under FP, three seedlings aged 28 days are transplanted in respective hills at random spacing. The fields are then flooded with water throughout the growing period. For SRI practice, factors considered as essential were transplanting only one seedling per hill aged 8–15 days with spacing of at least 20cm by 20cm; weeding the crop at least three times at intervals of ten days; and intermittently irrigating the fields. The contributions of using organic manure for fertilization and soil-aeration weed control methods were not considerations in this study since the availability of organic materials and mechanical push-weeders were challenges at the time of study. A total of 40 farmers in 10 units out of the 50 SRI farmers from 18 units of the irrigation scheme were sampled. Benefit–cost relationships were estimated using tabular analysis of all the variable costs and income from production using the survey data. On average, yield under SRI management increased by 1.6t/ha (33%), with seed requirements reduced by 87% and, water savings of 28%. SRI required 9% more labor than FP on average, but this factor of production showed great variability; in three Mwea units, labor costs were reduced by an average of 13%. SRI required 30% more labor for weeding than FP in the first season, but this was reduced to 15% in the second season when push-weeders became available. The results showed SRI giving a higher benefit–cost ratio of 1.76 and 1.88 in the first and second seasons, respectively, compared to 1.3 and 1.35 for FP. The results indicated that SRI practices of planting younger seedlings, with wider spacing and intermittent irrigation, lead to increased paddy rice yields with concomitant rise in the income accruing to farmers. Possibly further increases in net benefit could come with enhanced availability of mechanical weeders and using organic material for fertilization. Up-scaling of SRI in Mwea can be expected to help achieve greater national and household food security
Aflatoxin B1: Chemistry, Environmental and Diet Sources and Potential Exposure in Human in Kenya
(IntechOpen, 2019-10-05) Lalah, Joseph Owuor; Omwoma, Solomon; Orony, Dora A. O.; Lalah, Joseph Owuor; Omwoma, Solomon; Orony, Dora A. O.
Cancer incidences and mortality in Kenya are increasing according to recent reports and now number among the top five causes of mortality in the country. The risk factors responsible for this increase in cancer incidences are assumed to be genetic and/or environmental in nature. The environmental factors include exposure to carcinogenic contaminants such aflatoxins (AFs). However, the exact causes of the increase in cancer incidences and prevalence in many developing countries are not fully known. Aflatoxins are known contaminants produced by the common fungi Aspergillus flavus and the closely related Aspergillus parasiticus which grow as moulds in human foods. Aflatoxin B1 (AFB1) is most common in food and is 1000 times more potent when compared with benzo(a)pyrene, the most potent carcinogenic polycyclic aromatic hydrocarbon (PAH). Aflatoxins have therefore drawn a lot of interest in research from food safety and human health point of view. In this chapter, the chemistry, synthesis, identification, toxicology and potential human health risks of AFB1 in Kenya are discussed.
Aflatoxin Contamination of Maize and Groundnut in Burundi: Distribution of Contamination, Identification of Causal Agents and Potential Biocontrol Genotypes of Aspergillus Flavus
(Frontiers, 2023) Nsabiyumva Gedeon; Muteg Charity K; Wagacha John M; Mohamed Asha B; Njeru Nancy K; Niyuhire Marie C; Joseph Atehnkeng; Njukwe Emmanuel; Cotty Peter J; OrtegaBeltran Alejandro; Bandyopadhyay Ranajit
Aflatoxin contamination of the staples maize and groundnut is a concern for health and economic impacts across sub-Saharan Africa. The current study (i) determined aflatoxin levels in maize and groundnut collected at harvest in Burundi, (ii) characterized populations of Aspergillus section Flavi associated with the two crops, and (iii) assessed aflatoxin-producing potentials among the recovered fungi. A total of 120 groundnut and 380 maize samples were collected at harvest from eight and 16 provinces, respectively. Most of the groundnut (93%) and maize (87%) contained aflatoxin below the European Union threshold, 4 μg/kg. Morphological characterization of the recovered Aspergillus section Flavi fungi revealed that the L-morphotype of A. flavus was the predominant species. Aflatoxin production potentials of the L-morphotype isolates were evaluated in maize fermentations. Some isolates produced over 137,000 μg/kg aflatoxin B1. Thus, despite the relatively low aflatoxin levels at harvest, the association of both crops with highly toxigenic fungi poses significant risk of post-harvest aflatoxin contamination and suggests measures to mitigate aflatoxin contamination in Burundi should be developed. Over 55% of the L-morphotype A. flavus did not produce aflatoxins. These atoxigenic L-morphotype fungi were characterized using molecular markers. Several atoxigenic genotypes were detected across the country and could be used as biocontrol agents. The results from the current study hold promise for developing aflatoxin management strategies centered on biocontrol for use in Burundi to reduce aflatoxin contamination throughout the value chain.
Aflatoxin Contamination of Maize and Groundnut in Burundi: Distribution of Contamination, Identification of Causal Agents and Potential Biocontrol Genotypes of Aspergillus Flavus
(Frontier, 2023) Nsabiyumva Gedeon; Mutegi Charity K; Wagacha John M; Mohamed Asha B; Njeru Nancy K; Ndayihanzamaso Privat; Niyuhire Marie C; Joseph Atehnkeng; Njukwe Emmanuel; Callicott Kenneth A; Cotty Peter J; Ortega-Beltran Alejandro; Bandyopadhyay Ranajit
Aflatoxin contamination of the staples maize and groundnut is a concern for health and economic impacts across sub-Saharan Africa. The current study (i) determined aflatoxin levels in maize and groundnut collected at harvest in Burundi, (ii) characterized populations of Aspergillus section Flavi associated with the two crops, and (iii) assessed aflatoxin-producing potentials among the recovered fungi. A total of 120 groundnut and 380 maize samples were collected at harvest from eight and 16 provinces, respectively. Most of the groundnut (93%) and maize (87%) contained aflatoxin below the European Union threshold, 4 μg/kg. Morphological characterization of the recovered Aspergillus section Flavi fungi revealed that the L-morphotype of A. flavus was the predominant species. Aflatoxin production potentials of the L-morphotype isolates were evaluated in maize fermentations. Some isolates produced over 137,000 μg/kg aflatoxin B1. Thus, despite the relatively low aflatoxin levels at harvest, the association of both crops with highly toxigenic fungi poses significant risk of post-harvest aflatoxin contamination and suggests measures to mitigate aflatoxin contamination in Burundi should be developed. Over 55% of the L-morphotype A. flavus did not produce aflatoxins. These atoxigenic L-morphotype fungi were characterized using molecular markers. Several atoxigenic genotypes were detected across the country and could be used as biocontrol agents. The results from the current study hold promise for developing aflatoxin management strategies centered on biocontrol for use in Burundi to reduce aflatoxin contamination throughout the value chain.
Agricultural Climate Atlas for Kajiado and Kiambu Counties, Kenya
(springer, 2021-11-04) Matsaba, Emmanuel Ochola; van Selm, Merlijn; Wesonga, John Mwibanda; Goosen, Hasse; Coninx, Ingrid; Koomen, Irene
Crop production in Kenya takes place mostly under rain-fed conditions, with weather fluctuations having a high impact on productivity. Significant changes in the climate are expected between now and the end of the century, while many smallholder farmers are ill-equipped to cope with climate-related risks. These challenges are exacerbated by the fact that agricultural investment decisions and policy aspects for systemic adaptation require long-term planning. Therefore, there is a need to know what kind of climate change to expect. A climate atlas was developed as an interactive and user-oriented tool to provide a first insight into the projected impact of climate change on the agricultural sector in Kajiado and Kiambu Counties in Kenya. The information is provided on a web-based platform and is easy to access by farmers, farmer organizations, agri-food businesses, policymakers, and investors for climate decisions and planning. The information results from downscaling global climate change models to the Kenyan context, combined with the local agricultural sector’s vulnerability information. Via graphs and interactive maps, projected climate impacts are presented. The climate atlas also comprises an expert tool that allows exploration of climate impacts for a tailored situation to evaluate particular crops and/or varieties’ suitability in a specific location. The climate atlas is critical for starting a dialogue on the climate challenges that affect the two counties. Results can be translated into investment portfolios for climate-proofing agribusinesses and accelerating investments due to the potential to mitigate climate-related risks.
Agricultural Residues as an Alternative Source of Fibre for the Production of Paper in Kenya A Review
(Asian Journal of Chemical Sciences, 2021-07-10) Otieno J. O; Okumu T. N; Adalla Morelly; Ogutu Fredrick; Oure Boniface
Abstract The pulp and paper industry is primarily dependent on fibrous wood for pulp and paper production. However, this over-dependence on fibrous wood poses serious environmental challenges such as the diminishing of the fibrous wood stocks, deforestation, emission of greenhouse gases, and global warming. Therefore, to mitigate these environmental challenges associated with its utilization for paper and pulp production, other sustainable raw material sources can also be considered for the production of paper and pulp. There are enormous benefits associated with the utilization of non-wood fibres as an alternative and sustainable raw materials source for the production of paper and pulp. These benefits have in the recent past prompted millers in China, India, Brazil, and the USA to consider the utilization of non-wood fibres in paper and pulp production. In Kenya, the pulp and paper industry is very much dependent on fibrous wood for production and the industry is yet to fully embrace the utilization of nonwood fibres for paper and pulp production. Further, the dependence on fibrous wood has contributed significantly to the decline of paper pulp and paper production, deforestation, and rise in paper importations due to insufficient raw material supplies. The importation of paper and pulp products has further led to the collapse of the paper industry in Kenya. The sector stands a chance of revival and vibrancy through the utilization of the abundant agricultural residues and feedstocks lying in the agricultural fields across the country. Similar experiences elsewhere have proved that the abundance of agricultural waste can be utilized for the production of paper and pulp due to their excellent fibre content for specialty papers, and easy pulpability. The agricultural residues are therefore considered a quintessential alternative and sustainable source of raw materials for the pulp and paper industry. Moreover, their utilization will mitigate environmental impacts such as deforestation, climate change, and pollution .
Agriculture Projects Offered for Examinations in Secondary Education:: Perceptions towards Factors Influencing Initiation and Implementation in Kisii District,Kenya Paperback
(‎ LAP LAMBERT Academic Publishing, 2012-03-14) Nyang'au Martha K.
Agriculture projects were introduced in Secondary Education examinations in 1989 to equip learners with basic skills for self-reliance. However, the primary objective is often down played. The initiation and implementation of the projects might be poor since schools struggle to exploit the examination process at the expense of equipping learners with the practical skills; hence there is need for improvement. It is recommended that the Ministry of Education should organize regular workshops to develop and sustain the positive perceptions of school principals and agriculture teachers towards factors influencing project initiation and implementation. And to encourage co-operation among them during initiation. Further, the Ministry, should incorporate in the training curriculum for agriculture educators the factors perceived to be influencing the projects. School principals, and possibly Board of Governors should provide financial resources to improve and sustain positive perceptions of learners towards the factors influencing implementation of the projects
An assessment of morphological and physiological traits that correlate with faster growth rate and high biomass production in Acacia tortilis (Forsk.) Hayne seedlings
(Advances in Life Science and Technology, 2015) Kireger, Eliud K.; Rop, Simon K.
Presently, there are no procedures for selecting superior genotypes at seedling stage. We do not know which morphological or physiological characteristics can be used to predict superior growth in trees. Field testing of genotypes requires a substantial amount of time and money before a genotype shows significant promise in the field. For this reason, morphological and physiological parameters that correlate with growth rate were sought as early indicators of field performance. Six seed provenances of Acacia tortilis (Forsk.) Hayne collected from areas of varying aridity where compared in biomass productivity and gas exchange traits. After 3.5 months of growth, biomass ranged from 1-2 g. Significant provenance variation was observed in total biomass productivity, root dry weight, leaf area, net photosynthetic rates per unit leaf area, stomatal conductance (P<0.001) and leaf transpiration rate (P<0.05). More xeric provenances exhibited lower biomass productivity compared to mesic ones. They also showed lower photosynthetic rates, stomatal conductance’s and low photosynthetic capacity. Larger leaf areas, high stomatal conductances and photosynthetic rates appeared to be positively correlated with total biomass productivity since faster growing provenances had a greater leaf area, higher stomatal conductance and photosynthetic rates. Taken together, the results suggest that differences in leaf area, stomatal conductance and photosynthetic rates (photosynthetic capacity) among provenances may be responsible for the variation in biomass productivity in Acacia tortilis provenances. The probable premise and sequence of physiological events responsible for the variability depends on photosynthetic rate, total leaf area and leaf longevity.
An Evaluation Of Farmers’ Perceptions Of And Adaptation To The Effects Of Climate Change In Kenya
(Alanya Alaaddin Keykubat University, Department of Economics and Finance, 2013) Ndambiri, Hilary K.; Ritho, Cecilia N.; Mbogoh, Stephen G.
The study was carried out to evaluate how farmers in Kyuso District have perceived and adapted to climate change. Data was collected from 246 farmers from six locations sampled out through a multistage and simple random sampling procedure. The Heckman probit model was fitted to the data to avoid sample selection bias since not every farmer who may perceive climate change responds by adapting. The analysis revealed that 94% of farmers in Kyuso District had a perception that climate was changing and as a result, 85% of these farmers had responded by adapting. In this regard, age of the household head, gender, education, farm experience, household size, distance to the nearest market, access to irrigation water, local agro-ecology, on and off farm income, access to information on climate change through extension services, access to credit, changes in temperature and precipitation were found to have significant influence on the probability of farmers to perceive and/or adapt to climate change. With the level of perception to climate change being more than that of adaptation, the study suggests that more policy efforts should be geared towards helping farmers to adapt to climate change.
Anthropogenic Nutrients and Phytoplankton Diversity in Kenya's Coastal Waters: An ecological Quality Assessment of Sea Turtle Foraging sites
(Marine polluition Bulletin, 2017) Oduor N. A; Munga C.M; Imbayi L.K; Botwe P.K; Nyanjong E.O; Muthama C.M; Mise N.A; Moosdorf Nils
Abstract We assessed ecological quality status (EQS) of coastal waters following claims of increasing sea turtle fibro-papillomatosis (FP) infections in Kenya, a disease hypothesized to be associated with ‘poor’ ecological health. We established widespread phosphate (P) and silicate (Si) limitation, dissolved ammonium contamination and an increase in potential harmful algal blooming species. Variations in the EQS was established in the sites depending on the indicators used and seasons. Generally, more sites located near hotels, tidal creeks, and estuarine areas showed ‘poor’, and ‘bad’ EQS during rainy period compared to dry season. Additionally, 90.1 % of the sites in ‘poor’ and ‘bad’ EQS based on dissolved inorganic nitrogen. Low dissolved oxygen, elevated temperature, salinity and ammonium, ‘poor’ EQS based on DIN, and potential bio-toxin-producing phytoplankton species characterized the FP prevalent areas, specifically during the dry season suggesting environmental stress pointing to the hypothesized connection between ecological and sea turtle health.
Antimalarial Activity of Nigella sativa L. Seed Extracts and Selection of Resistance in Plasmodium berghei ANKA in a Mouse Model
(Journal of Pathogens, 2021-02-03) Yusuf Rahma Udu; Oyweri Job; Gathirwa Jeremiah
Chemotherapy plays a crucial role in malaria control. However, the main obstacle to treatment has been the rise of parasite resistance to most antimalarial drugs. Artemisinin- based combination therapies (ACTs) remain the most effective antimalarial medicines available today. However, malaria parasite tolerance to ACTs is now increasingly prevalent especially in Southeast Asia presenting the danger of the spread of ACTs resistance to other parts of the world. Consequently, this creates the need for alternative effective antimalarials. (erefore, this study sought out to determine antimalarial potential, safety, and resistance development of the extracts in a mouse model. Method. Methanolic and ethyl acetate extracts were obtained by solvent extraction. (e extracts were assayed for acute toxicity in vivo. Additionally, the two extracts were evaluated for antimalarial activity in vivo against Plasmodium berghei ANKA strain by the 4-day suppressive test at 500, 250, and 125 mg/kg/day. Packed cell volume was evaluated to determine anemia manifestation. Finally, continuous drug pressure experiment at 500 mg/kg and DNA amplification via PCR were conducted. (e amplicons underwent through Sanger sequencing. Results. (ere was no toxicity realized in the animals at 2000 mg/kg. Importantly, high parasitemia suppression of 75.52% and 75.30% using a dose of 500 mg/kg of methanolic and ethyl acetate extracts, respectively, was noted. (e extracts were able to reverse packed cell volume reduction. Nigella sativa-resistant phenotype was selected as delayed parasite clearance. However, there was no change in the nucleotide sequences of PbMDR1 and PbCRT genes. Conclusion. (e results provide room for future exploitation of the plant as an antimalarial
Application of AquaCrop model in deficit irrigation management of cabbages in Keiyo Highlands
(2013-07-31) Kiptum C, K.; Kipkorir E, C.; Munyao T, M.; Ndambuki, J. M.
Crop growth can be simulated under different water application using simulation models. The main purpose of deficit irrigation is high water productivity with less application of water to plants. In this research, the potential of AquaCrop to simulate the growth of cabbages in Keiyo Highlands (0°22’45’’N and 35°32’9”, 2586 m.a.s.l) under nine different irrigation treatments in the dry season between December to February was studied. Statistical comparisons of observed and simulated biomass showed that R2 = 0.96, Root mean square error (RMSE) = 0.38 tons and coefficient of residuals = -0.17. The results showed that the model overestimated the biomass of cabbages. The model also provided excellent simulation of canopy and yield. In this study water productivity of 17 g/cm2 and Harvest index of 76% were found for cabbages. Key words: Deficit irrigation, AquaCrop, cabbage ‘Riana’ and water productivity.
Application of GIS on the Identification of Suitable Areas for Water Conservation Technologies in the Upper Tana Watershed of the Central Highlands of Kenya
(International Journal of Plant & Soil Science, 2019) Nganga B. W.; Nge’tich K. O.; Adamtey N.; Milka K.; Ngetich K. F.
Low adoption of soil water conservation technologies has been one of the main causes for decreased agricultural productivity in the Upper Tana Catchment of Kenya. Proper identification of locations to scale-out the individual technologies necessary to improve water conservation is a key determinant for the rate of adoption. Our main aim was to identify the suitable sites for water conservation technologies using the suitability model created by the model builder function in ArcGIS 10.5® . The model combined the thematic layers of soil texture, slope, rainfall, and stream order, which were acquired from assorted online sources. The factors were converted to raster format and reclassified based on their suitability and were assigned fixed scores and weights by use of multi influencing factor (MIF) method. The suitability evaluation was carried out by use of weighted overlay to produce suitability classes for each of the water conservation technique. The delineated suitability maps indicated that check dams are highly suitable in 50% of the study area. Mulching, on the other hand, is highly suitable for 49% of the study area. Zai pits are highly suitable in 43% of the study area. Majority of the study area is moderately suitable for the use of terraces, covering 41% of the study area. The highly suitable areas for the Checkdams are Machakos, Kitui, Tharaka-Nithi and lower parts of Embu. The highly suitable areas for mulching are Kirinyaga, Murang’a, Nyandarua and Nyeri. The highly suitable areas for the Zai pits are Kitui, lower parts of Tharaka-Nithi and the highly suitable areas for the terraces are Murang’a, Nyeri and Kirinyaga. Furthermore, the results demonstrated the effectiveness of GIS in delineating the suitable areas for the use of water conservation technologies.
Application of the DPSIR Framework to Coastal and Marine Fisheries Management in Kenya
(Ocean Science Journal, 2020-06-09) Dzoga, Mumini; Simatele, Danny Mulala; Munga, Cosmas; Yonge, Shadrack
Natural resource management frameworks are important in generating information that promotes the development of appropriate policies and regulation for effective management and utilization of different aspects of ecosystems. The Drivers-Pressure-State-Impact and Response (DPSIR) framework is one of such frameworks which has been widely applied globally in assessing, addressing and communicating with regard to environmental problems. This framework provides a nexus between the causes of environmental problems and the resultant pressures, associated impacts and responses needed to resolve and manage specific environmental issues and challenges. Based on improved management evidence for natural resources enabled by the application of the DPSIR framework globally, this paper is a review of the application of the framework in the management of coastal and marine fisheries resources in Kenya. Findings indicate that there exists a limited number of studies which have adopted the DPSIR framework approach in Kenya, and these are mainly focused on terrestrial ecosystems. However, coastal and marine resources have been well studied in Kenya using different methodological approaches that have given insights into the conditions of resources. This review, therefore, analyzed these studies to understand drivers, pressures, states, impacts and responses in relation to coastal and marine fisheries resources in Kenya. The main drivers observed were a high population growth rate of 3.7% as well as a high dependency rate on natural resources of 74% and 58% in Ngomeni and Kipini fishing areas of north coast Kenya, respectively. There is also a lack of understanding regarding the potential of the DPSIR framework to effectively manage coastal and marine fisheries resources, particularly in the context of sub-Saharan Africa, taking Kenya as a case study. This may result in the development of fisheries regulations that are not holistic in their approach, and therefore, ineffective from a management perspective. Within this context, this paper provides a discourse on how the DPSIR framework may enhance coastal and marine fisheries resources management in Kenya.
Assessing Sensory Characteristics and Consumer Preference of Legume-Cereal-Root Based Porridges in Nandi County
(Journal of Food Quality, 2019-06-18) Gitau Peninah W.; Kunyanga Catherine N.; Abong’ George O.; Ojiem John O.; Muthomi James W.
Previously, porridge has been cereal based, consumed as a beverage or weaning food. Malnutrition among children has necessitated inclusion of legumes and roots in an e ort to boost nutrient density. erefore, the current study aimed at identifying the most acceptable porridge based on di erent food ingredient combination. Composite porridge our included legumes (soybean, groundnut, and lablab), cereals ( nger millet, sorghum, maize, and wheat), pseudocereals (pumpkin seed, buckwheat, and amaranth seed), and roots (cassava and arrowroot). New composite porridge ours were formulated using Nutrisurvey linear programming software. Di erent composite ours formulated to target either school-going children or a family setup were subjected to sensory analysis and the consumer preference test. Eight new formulations were developed. Buckwheat, wheat, and arrowroot were eliminated, maize and lablab content (%) were reduced, and cassava and nger were increased in the new formulations. A total of 149 participants composed of men (30.9%) and women (69.1%) aged between 11 and >60 yrs were interviewed. Newly formulated porridges were more preferred to the previous porridge formulations on color (40–54.2%), smell (40–52.4%), taste (41.5–47.5%), texture (58.3%), viscosity (35.4–45.8%), and overall acceptability (35–54.2%). e most cited reason for liking or disliking a particular porridge was taste (38.9%) and texture (32.2%), respectively. However, all the sensory attributes positively correlated with overall acceptability. Increased nger millet and cassava proportions in the newly formulated composite porridge our highly in uenced their high acceptability. us, consumer acceptability of new products is key for their adoption.
Assessment of Ecological Vulnerability to Climate Variability on Coastal Fishing Communities: A Study of Ungwana Bay and Lower Tana Estuary, Kenya
(Elsevier, 2018-09-01) Dzoga, Mumini; Simatele, Danny; Munga, Cosmas
Fisheries resources are important in supporting the livelihood of many coastal communities especially in the developing tropical countries. Fisheries resources however, continue to face unprecedented pressure from the impacts of climate change, and this presents both ecological and socio-economic challenges to the dependent communities. This paper assessed the ecological vulnerability to climate variability of artisanal fishing communities in Ungwana Bay and the Lower Tana Delta in Kenya, using selected fin fish species. A combination of approaches were adopted and used to identify and determine exposure, sensitivity, and adaptation indicators. These included a critical review of existing literature, socio-economic survey, and computation of temperature and rainfall variation using long term data from 1983 to 2015. The method of Equal Weights (EW) was applied to all indicators after normalization. The data was normalized in a scale of 0–1, where 0 indicated low vulnerability level and 1 high vulnerability. By using composite index, the selected Ngomeni and Ozi fishing communities within the larger Ungwana Bay and Lower Tana Delta indicated high levels of vulnerability of 0.9 and 0.8 respectively. Due to high vulnerability level and poor adaptation capacity by the local fishing communities in the selected study sites, we recommend government and non-governmental agencies to reinforce community based organizations (CBOs) activities on ecological conservation and social network creation to promote short and long term adaptation measures.

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