Natural Resources Management

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Aluminum tolerance mechanisms in Kenyan maize germplasm are independent from the citrate transporter ZmMATE1
(Scientific reports, 2020) Matonyei, Thomas K.; Barros, Beatriz A.; Guimaraes, Roberta G. N.; Ouma, Evans O.; Cheprot, Reuben K.; Apolinário, Leandro C.; Ligeyo, Dickson O.; Costa, Marcella B. R.; Were, Beatrice A.; Kisinyo, Peter O.; Onkware, Augustino O.; Noda, RobertoW.; Gudu, Samuel O.; Magalhaes, JurandirV.; Guimaraes, Claudia T.
Aluminum (Al) toxicity on acid soils adversely affects maize yields, which can be overcome by combining soil amendments with genetic tolerance. In maize, ZmMATE1 confers Al tolerance via Al-activated citrate release, whereby citrate forms non-toxic complexes with Al3+ in the rhizosphere. Here, we investigated Al tolerance mechanisms in maize germplasm originated from Kenya based on quantitative trait loci (QTL) mapping. Five QTLs and four epistatic interactions explained ~51% of the phenotypic variation for Al tolerance. The lack of Al tolerance QTL on chromosome 6 and the much lower expression of ZmMATE1 in both Kenyan lines than in Cateto Al237, which donates the superior allele of ZmMATE1, strongly indicate that this gene does not play a significant role in Al tolerance in neither parent. In turn, maize homologs to genes previously implicated in Al tolerance in other species, ZmNrat1, ZmMATE3, ZmWRKY and ZmART1, co-localized with Al tolerance QTL and were more highly expressed in the parent that donate favorable QTL alleles. However, these candidate genes will require further studies for functional validation on maize Al tolerance. The existence of Al tolerance mechanisms independent from ZmMATE1 suggests it is possible to develop highly Al tolerant cultivars by pyramiding complementary Al tolerance genes in maize.
Wildlife Population Change in Africa from the Eyes of the Public—The Case of Mara Enoonkishu Conservancy in Southern Kenya
(Scientific Research Publishing, 2016-06) Masiga, Dorothy Syallow; Mwaura, Francis; Mukhovi, Mikalitsa S.
The aims of the study were to: 1) determine the wildlife population trends in the Mara Enoonkishu Conservancy from the eyes and minds of the public, 2) assess the recent trends in wildlife populations based on actual scientific counts, and 3) compare the two patterns and establish whether they are similar or not. The solicitation of public views was based on household surveys using a standard questionnaire which was administered to 115 randomly selected respondents. The dominant wildlife species according to 39% of the respondents was the elephant followed by the zebra with 35%. 40% of the respondents indicated that the rhino population had declined followed by wild dogs (7%) and cheetah (6%). The actual counts showed that the herbivores with increasing populations included the rhino (r2 = 0.9992), impala (r2 = 0.9824), Thomson’s gazelle (r2 = 0.6965), Grant’s gazelle (r2 = 0.7052), elephant (r2 = 0.5798), and topi (r2 = 0.4426) while the increasing predators included the lion (r2 = 1.000), cheetah (r2 = 0.9093) and hyena (r2 = 0.8462). The actual wildlife counts appeared to tally with the public views only for the elephant and zebra. The actual counts contradicted the public views in terms of the rhino, lion and gazelles whose numbers were on the increase but the people did not appear to notice. Based on this, it was concluded that the public view on the wildlife population trend was not similar to the actual wildlife population status on the ground based on scientific monitoring
Efficacy of Bomas (Kraals) in Mitigating Livestock Depredation in Maasai Mara Conservancies, Kenya
(MDPI, 2023-03) Wakoli, Elizabeth; Syallow, Dorothy Masiga; Evans Sitati; Webala, Paul W.; Ipara, Hellen; Finch, Tabitha
Livestock depredation is a major conservation challenge globally, causing significant economic losses to pastoralists and threatening large carnivore species outside protected areas. Our study investigated the temporal and spatial distribution of livestock depredation incidences, carnivore species associated with livestock depredation, and assessed mitigation measures in Maasai Mara Conservancies in Southern Kenya. Using daily monitoring of livestock depredation cases, we made comparisons between livestock attacks occurring in predator-proof bomas and those with traditional kraals. A total of 305 livestock depredation incidents were recorded between January and December 2021, translating to a total tally of 1411 livestock maimed or killed. Most livestock depredation incidents occurred during the day (59%) as opposed to night (41%), but this difference was not significant. Livestock depredation incidents in the nighttime occurred mostly inside traditional kraals (34%) and occurred the least in predator-proof kraals (2%). Lions were responsible for more livestock attacks in the grazing fields compared with leopards, hyenas, and wild dogs. Hyenas were more daring and attacked livestock inside traditional bomas relative to lions and leopards. Our study concludes that predator-proof bomas are more effective in minimizing livestock depredation and can be embraced as a sound intervention for human–carnivore co-existence in communities’ wildlife conservation areas.
Fanya juu Terraces Improve Maize (Zea mays L.) and Bean (Phaseolus vulgaris L) Grain Yields on Hardsetting Soils of Semi-arid Eastern Kenya
(2022) Njiru, Emerita N.; Gachene, Charles K.; Baaru, Mary W.
Aims: Fanya juu terraces are constructed by digging a ditch and throwing the soil up-slope with the sole purpose of maintaining an embankment to slow down runoff flow. The effect of the terraces on crop yields along the slope varies with the soil type. The aim of this study was to determine the effect of Fanya juu terraces on maize (Zea mays L.) and bean (Phaseolus vulgaris L.) yields and how these yields differ with slope positions and depth of the ditches. Study Design: Split-split plot design with four replications. Place and Duration of Study: The trial was established on Luvisols in Mua location, Machakos County in Eastern Kenya at 37o15’E 1o29’S and 37o15’E 1o29’S during both long rain (LR) and short rain (SR) seasons of 2014 and 2015 (February 2014 to March 2015). Methodology: Treatments consisted of three ditch depths (60 cm, 30 cm and 0 cm (control)) in the main plots and three cropping systems (maize/bean intercrop, sole maize and sole bean) in the sub plots. Grain yields were compared across the seasons at the upper, middle and lower slope positions of the terraces using analysis of variance and means separated using least significant difference at P≤0.05. Results: There were significant differences in maize grain yields in the interactions of ditch depth and slope position (P=0.004) and ditch depth and season (P<0.001). Higher maize yields were realized when ditches were constructed than in the control. Yields increased from the lower to the upper slope position of the terraces with 30 cm ditch by 49.8% and in the 60 cm by 41.6%. Average yields from treatments with 30 cm ditch were significantly higher than from the control but non-significant from those in the 60 cm ditch. Significant differences (P=0.037) in bean grain yields were observed in interactions of ditch depth and slope position. Higher yields were obtained from the lower position of the 30 cm ditch than the middle and upper positions. Significant differences (P=0.033) were also found in interactions of ditch depths, cropping systems and seasons. Conclusion: The results indicate that Fanya juu terraces had a significant effect on crop yields on hardsetting soils. The study recommends construction of Fanya juu terraces with a ditch depth of 30 cm and intensive management of the lower slope position for improved maize and bean production on hardsetting soils in marginal areas.
Assessment of soil moisture and nutrients on terrace slope of hard-setting soils in semi-arid eastern Kenya
(Tropical and Subtropical Agroecosystems, 2022) Njiru, Emerita; Baaru, Mary; Gachene, Charles
Background: Terraces are structures consisting of ditches and embankments used to control erosion and increase land productivity. There is, however, little emphasis on the effects of the ditch dimensions on soil moisture and nutrient dynamics. Objective: To determine the effect of varying ditch depths on soil moisture and nutrient quantities and their variability within the terrace slope on hard-setting soils. Methodology: Soil samples were collected seasonally in 2014 and 2015 from terraces with different ditch depths (60, 30, and 0 [control] cm) for the determination of soil moisture content (SMC). The samples were collected from the upper, middle and lower slope positions of each terrace. Soil from the three slope positions of each terrace was also sampled at the end of the study and analyzed for total nitrogen (%TN), available phosphorous (Av. P), exchangeable potassium (K+ ) and % organic carbon (OC) contents. Data were subjected to a two-way analysis of variance and differences in means determined at a 95% level of confidence. Results: Significant interactions (P<0.001) in SMC were observed between seasons, ditch depths and slope positions. Higher SMC was found in treatments with 30 and 60 cm ditch depths in all the slope positions and seasons compared to the control. Soil moisture contents in the lower and upper slope positions were significantly different between the terraces with 30 and 60 cm ditch depths when rainfall was high and evenly distributed, but non-significant in poorly distributed rainfall seasons. Significant differences (P ≤ 0.05) in contents of total nitrogen and available phosphorous were found between the upper and lower slope positions of the terraces with ditches. Implications: The effect of ditch depths on moisture, total nitrogen and available phosphorous contents and their variability within the slope depended on the amount and distribution of rainfall. Conclusion: Construction of terraces with shallow ditch depths (of 30 cm) is recommended to conserve soil moisture and nutrients nitrogen and phosphorous on hard-setting soils in the marginal areas of semi-arid Eastern Kenya.
Breeding phenology and population dynamics of the endangered Forest Spiny Reed Frog Afrixalus sylvaticus Schiøtz, 1974 in Shimba Hills, Kenya
(Wildlife Informaon Liaison Development Society, 2022-07-26) Koskei, Alfayo; Eshiamwata, George; Kirui, Bernard; Cheruiyot, Phylus
Afrixalus sylvaticus Schiøtz, 1974 is a species of hyperoliid frog inhabiting coastal forest Kenya. It is classified as endangered under IUCN B2ab(iii) ver 3.1 and occurs in the Shimba Hills National Park and hinterlands. Habitat loss and other human activities are threatening the species. Therefore, understanding the breeding ecology and population dynamics is important for its conservation. This study assessed the breeding ecology and population dynamics of the species in the protected and community landscapes in Shimba Hills National Reserve in Kenya. Data was collected through ecological surveys conducted from June 2016 to July 2017 using a visual encounter surveys (VES) method. The results show that the species was more abundant during the wet season than dry (58% and 42%, respectively). The population estimate was 192 individuals and a density of 0.98 individuals/km2. Regarding the morphology, the mean snout-vent length (SVL) for males was 15.12 mm and females 15.96 mm, but there was no significant difference (t-test = 0.87, p = 0.390, df = 39). The mean weight of both gravid and non-gravid females was 6.05 g and males was 4.82 g. The weights were statistically different between both sexes (t-test = 3.50, p-value = 0.001, df = 39). The sex ratio was 1:2 (male: female). There was more activity in the wet season (April and May), and the breeding habitats were reeds and water lilies. The threats identified to their habitat include; human activities such as bush burning, livestock grazing, drainage, and plantation of exotic tree species (Eucalyptus sp.) that have led to habitat loss and degradation. The study recommends that the reforestation processes such as plantation of exotic species such as Eucalyptus sp. and Casuarina sp. and bush burning in the wetlands and species habitats must be discouraged among the stakeholders (community and park management). Moreover, more synchronized studies are necessary to highlight the driver(s) of imbalanced sex ratios and species habitat shifts.
Value of ecosystem services and socio-economic factors that enhance community participation in forest management in Aberdare forest, Kenya
(Egerton University, 2018-05) Wambugu, Elizabeth Wanjiru
Forest ecosystems have been a valuable source of economic wellbeing of human populationsfor centuries, particularly to the forest adjacent communities. The relationship between humanwellbeing and ecosystems consist of complex systems that are mostly nonlinear, uncertain andoften not clearly understood. To enhance forest sustainability, the deliberate evaluation ofecosystem services, human interactions and appropriate ways to involve the public inmanagement is imperative. However, little has been done to demonstrate how forest ecosystemservices and public participation could contribute to forest conservation and socio-economicdevelopment of forest-dependent communities. This study therefore evaluated forestecosystem services and socio-economic factors that influence community participation inforest management to enhance forest conservation while improving livelihoods. To achievethis objective, the study interviewed local communities bordering Aberdare forest ecosystem.The study was based on semi-structured questionnaires administered to a stratified randomsample of 202 households, six focus group discussions and benefit transfer method. The datawas analyzed using Chi square, Spearman’s rho correlation and regression analysis. Thefindings of this study showed that the net annual benefit of ecosystem services wasapproximately KES 36.8 (US$ 0.37) billion where regulating services constituted 98%. Thecommunities lost KES 172 (US$ 1.7) million annually to wildlife. The net annual return fromforest conservation was higher as the opportunity cost of forest land conversion wasapproximately KES 4.2 (US$ 0.04) billion. The significant factors included forest managementapproach (χ² = 17.551, p < 0.001), distance to the Forest Reserve (χ² = 29.071, p < 0.001),distance to the National Park (χ² = 27.303, p = 0.008), gender of household head (χ² = 10.719,p = 0.002), land tenure (χ² = 34.313, p < 0.001) and sources of income (χ² = 31.353, p < 0.001).Economic factors that included farm size, household size, annual income, land tenure, andimportance of the forest ecosystem were found to significantly influence the regression modelwith R2 being 0.703. It can be concluded that if only provisioning ecosystem services areconsidered, there is a net loss arising from conservation. Therefore, it is imperative to encashall the ecosystem services to decrease forest conversion and depletion based on economicforces. Further, increasing economic benefits to the community will positively influenceparticipatory forest management. This study recommends that to fully engage the communityin participatory forest management, there is need to consider their basic livelihood strategiesas well promote forest products availability on the farmlands to reduce pressure on the forestecosystems.
Effect of Forest Management Types on Soil Carbon Stocks in Montane Forests: A Case Study of Eastern Mau Forest in Kenya
(Hindawi Publishing Corporation, 2020-10-17) Tarus, George; Nadir, Stanley
Mau Forest, a major forest reserve in Kenya, has experienced anthropogenic disturbances through encroachment and forest fires. This study aimed at comparing the soil carbon stocks in different forest management types as well as how seasonal climatic changes influence its dynamics. The study was undertaken in the Eastern Mau block (Sururu) which forms part of the greater Mau Forest Complex. The forest management interventions have been in place for over 15 years with disturbed (fire) natural forest experiencing fires in 2005, 2007, and 2014 while cypress plantations were established in 1994. A nested experimental design was used in data collection, where thirty-two sample plots were nested into four blocks each measuring 100 m² delineated by forest management types (disturbed by fire, natural forest, undisturbed natural forest, plantation, and glades). In each plot, data on soil carbon stocks, soil bulk density, soil moisture, and temperature were collected for both dry and wet seasons. Data collection was carried out between November 2015 and December 2016. The results indicated that there were no significant differences in the carbon stocks among the forest management types (F4,16 = 0.61, ). However, seasonal weather changes significantly affected the amount of carbon stocks among the forest management types (F4,16 = 0.61, ). The undisturbed natural forest had the highest mean soil carbon stocks, while the plantation forest had the lowest as follows: undisturbed natural forest (135.17 ± 35.99.0 Mg·C−ha), disturbed natural forest by fire (134.52 ± 38.11 Mg·C−ha), glades (122.4 ± 64.9 Mg·C−ha), and plantation forest (116.51 ± 39.77 Mg·C−ha). Furthermore, the undisturbed natural forest management had the highest bulk density (0.66 g/cm³), while the disturbed (fire) natural forest had the lowest (0.59 g/cm³). These values were low compared to most normal mineral soils which have a bulk density of between 1.0 g/cm³ and 1.5 g/cm³. There was a significant () relationship between seasonal weather (temperature) changes and soil carbon stocks under different forest management types with the relationship being stronger in soils under glades (r² = 0.62) and weak in the undisturbed natural forest (r² = 0.26). In conclusion, forest disturbances have an impact on soil carbon stocks, and for effective management of forest towards climate stabilization, then disturbance should be minimized if not avoided.1. IntroductionForest soils are a major sink of terrestrial carbon containing more than double the amount of carbon found in forest tree biomass [1, 2] and play a fundamental role in the global carbon cycle [3–6]. The role of forest soils as either a source or sink has become vital when assessing changes in atmospheric carbon dioxide concentrations mainly due to the growing interest of reducing the greenhouse emissions [7–10].Traditionally, forest management practices focused mainly on increasing the forest productivity and growing biomass stock with little effort on managing the soil carbon. Even though the effects of forest management on soil carbon stocks are not well understood [11], consensus exists that some forest management operations have an impact on carbon budget including losses of carbon from mineral soils [12].Forest management operations have been known to affect the carbon gains and losses by changing the level of inputs to the soil carbon pools, rates of microbial decomposition, changing environmental conditions such as temperature and moisture, and changing the quality of litter [2, 11]. Variability in weather parameters especially temperature and soil moisture has been reported to influence soil organic matter decomposition [13]. In addition, wet and cold climates store more soil carbon compared to dry and hot climates with suggestions of the existing optimum climate influencing soil carbon storage [14]. Seasonal dry and wet conditions have no significant change in total soil carbon in tropical forests [15] although biomass accumulation in disturbed forests is reported to be influenced by temperature [16].The Mau Forest Complex (MFC) forms the largest closed-canopy forest ecosystem in Kenya, covering over 400,000 hectares of land [17, 18]. This forest ecosystem is comprised of several forest blocks including the Eastern Mau Forest block. MFC provides critical ecological goods and services such as river flow regulation, flood mitigation, recharge of groundwater, reduced soil erosion and siltation, water purification, conservation of biodiversity, and microclimate regulation [17, 19, 20]. Despite the above critical functions, the Mau Forest Complex has been impacted by extensive irregular and ill-planned settlements as well as illegal forest resource extraction that have reduced the cover by more than 7% in the past 21 years [21]. To address these negative trends, the government enhanced forest management through the deployment of various interventions including both policy and restoration measures.The forest reserve is being subjected to heterogeneous management to address the varied previous disturbance levels and existing resource types. These management activities are anticipated to affect the carbon dynamics such as carbon emissions and sequestration.Therefore, the aim of this study was to evaluate the impacts of the forest management on the soil carbon stocks in the Eastern Mau Forest reserve. The findings of this study contribute knowledge towards carbon management, climate change mitigation mechanisms such as Reduction of Emission from Deforestation and forest Degradation (REDD+), and the role of conservation in the sustainable management of forests and enhancement of forest carbon stocks and climate change policies.2. Materials and Methods2.1. Description of the Study Area2.1.1. LocationThis study was undertaken in Sururu forest block (Figure 1). The block is part of the larger East Mau Forest reserve. The selection of the study site was centered on the application of management objectives (plantation forest, undisturbed natural forest, disturbed (fire) natural forest, and glades). The management actions are critical in the development, conservation, and management of Kenya’s forest resources [17]. The Eastern Mau Forest is 50 km south of Nakuru Town and positioned within UTM zone 37S and the coordinate bounds (161237, 9937639); (161237, 9924748); (1773018, 9937639); (1773018, 9924748) (KFS, 2011) (Figure 1). Sururu forest block covers an area of approximately 13364.4 ha [17, 20]. Despite the complexity in the plant formation, there is a broad altitudinal zonation. The lower zone is comprised of lower montane forest which occurs below 2,300 m and then it transitions into middle montane at 2350 m. The middle montane is composed of thickets of bamboo (Arundinaria alpine) mixed with forest. The upper zone ranging from 2420 m to 2600 m at the escarpment crest forms the upper montane Sclerophyllous forest. The optimal conditions for forest growth are within the lower montane forest zone. This zone is characterized by tree species that include Aningeria adolfi-friedericii and Strombosia scheffleri [18]. Some of the major rivers and streams forming up the hydrological systems of Lake Victoria, Lake Nakuru, Lake Baringo, and Lake Natron originate from Eastern Mau, thus making it a critical watershed within the Mau Forest Complex [20].
Factors Influencing the Implementation of Environmental Management Practices in Small and Medium Sized Manufacturing Entreprises in Nakuru Town, Kenya
(Bharti Publications, 2020-11) Walela, Hillary Barasa
Small and Medium-sized Enterprises (SMEs) play crucial role in economic growth for many nations globally. Whereas growth of SMEs contributes to economic growth and development of a society they can also cause a significant environmental degradation. Despite continued emphasis on environmental management in Kenya, there is limited study that has focused on the environmental management strategies undertaken by manufacturing SMEs in Nakuru Town. The aim of this study was to assess the factors influencing the implementation of environmental management practices in small and medium sized manufacturing enterprises in Nakuru Town. The study employed cross sectional research design where data was collected through structured questionnaire, face to face interviews and observations. The respondents were owners of the industry, technical managers or administrative staff. Simple random sampling procedure was used to select 32 manufacturing SMEs in Nakuru County. Data was analyzed using descriptive statistics and results presented as frequency tables and bar graphs. Logistic regression model was used to determine factors influencing the adoption of environmental management practices. The findings indicate that the owners/managers of SMEs in Nakuru Town had limited awareness with regard to environmental impacts surrounding their business. The SME owners/managers had a positive attitude towards environmental management. But it was established that the adoption of environmental practices among the selected small and medium manufacturing enterprises was still very low or non-existent. On the factors influencing the adoption of environmental practices, the size of the firm, level of awareness and financial resources had significant influence on the decision to undertake environmental management practices. New efforts are therefore required to engage the SMEs sector in addressing environmental issues by building capacity such as raising awareness and offering incentives on programs that supports sustainable practices.
Association between Anthropogenic Sources of Outdoor Air Pollution and Lichen Diversity, in Nakuru Town, Kenya
(Scientific & Academic Publishing, 2019) Kimani, Harriet W.; Moturi, Wilkister N.; Kariuki, Samuel T.
The purpose of this study was to assess urban lichen diversity in relation to anthropogenic sources of outdoor air pollution, in Nakuru town, Kenya. An ecological survey was conducted in six sampled sites of the town and data of lichen diversity and anthropogenic sources of outdoor air pollution, analyzed. Multi-stage sampling technique was used. A total of 51 lichen species were identified while 6 anthropogenic sources of outdoor air pollution were observed. Results from Fisher’s exact test analysis showed, significant association between the 6 observed anthropogenic sources of outdoor air pollution and lichen diversity. It was concluded that, different anthropogenic sources of outdoor air pollution affect presence and absence of urban lichen species. Hence, more studies on lichens and outdoor air pollution should be conducted in Kenya, to conclusively determine whether lichens should be adopted as an alternative biological method to technological devices, for assessing air pollution.
Characterization of Forest Fire Emissions and Their Possible Toxicological Impacts on Human Health
(Institute of Forest Science, kangwon National University, 2017-05-31) Kibet, Joshua; Bosire, Josephate; Kinyanjui, Thomas; Lang'at, Moses; Rono, Nicholas
In flight particulate matter particularly emissions generated by incomplete combustion processes has become a subject of global concern due to the health problems and environmental impacts associated with them. This has compelled most countries to set standards for coarse and fine particles due to their conspicuous impacts on environment and public health. This contribution therefore explores forest fire emissions and how its particulates affects air quality, damage to vegetation, water bodies and biological functions as architects for lung diseases and other degenerative illnesses such as oxidative stress and aging. Soot was collected from simulated forest fire using a clean glass surface and carefully transferred into amber vials for analysis. Volatile components of soot were collected over 10 mL dichloromethane and analyzed using a QTOF Premier-Water Corp Liquid Chromatography hyphenated to a mass selective detector (MSD), and Gas Chromatograph coupled to a mass spectrometer (GC-MS). To characterize the size and surface morphology of soot, a scanning electron microscope (SEM) was used. The characterization of molecular volatiles from simulated forest fire emissions revealed long chain compounds including octadec-9-enoic acid, octadec-6-enoic acid, cyclotetracosane, cyclotetradecane, and a few aromatic hydrocarbons (benzene and naphthalene). Special classes of organics (dibenzo-p-dioxin and 2H-benzopyran) were also detected as minor products. Dibenzo-p-dioxin for instance in chlorinated form is one of the deadliest environmental organic toxins. The average particulate size of emissions using SEM was found to be $11.51{\pm}4.91{\mu}m$. This study has shown that most of the emissions from simulated forest fire fall within $PM_{10}$ particulate size. The molecular by-products of forest fire and particulate emissions may be toxic to both human and natural ecosystems, and are possible precursors for various respiratory ailments and cancers. The burning of a forest by natural disasters or man-made fires results in the destruction of natural habitats and serious air pollution.
Impacts of forest management type and season on soil carbon fluxes in Eastern Mau Forest, Kenya
(Wiley-Blackwell Publishing Ltd, 2018-11-24) Tarus, George K.; Kirui, Bernard K.; Obwoyere, Gilbert
The value of ecosystems functions performed by forests in the climate change era has prompted increasing attention towards assessment of carbon stocks and fluxes in tropical forests. The aim of this study was to understand how forest management approaches and environmental controls impacted on soil CO2 efflux in a tropical Eastern Mau forest which is one of the blocks of the greater Mau complex in Kenya. Nested experimental design approach was employed where 32 plots were nested into four blocks (disturbed natural, undisturbed natural, plantation and glades). In 10 m2 plots, data were collected on soil CO2 efflux, soil temperature and soil moisture using soda lime methods, direct measurement and proxy techniques, respectively. There was significant forest management type effect (F3,127 = 3.01, p = 0.033) and seasonality effect (t test = 3.31, df = 1, p < 0.05) on mean soil CO2 efflux. The recorded mean soil CO2 efflux levels were as follows: plantation forest (9.219 ± 3.067 g C M−2 day−1), undisturbed natural forest (8.665 ± 4.818 g C M−2 day−1), glades (8.592 ± 3.253 g C M−2 day−1) and disturbed natural forest (7.198 ± 3.457 g C M−2 day−1). The study concludes that managing a forest in plantation form is primarily responsible for forest soil CO2 efflux levels due to aspects such as increased microbial activity and root respiration. However, further studies are required to understand the role and impact of soil CO2 efflux on the greater forest carbon budget.
Fire-induced negative nutritional outcomes for cattle when sharing habitat with native ungulates in an African savanna
(British Ecological Society, 2016-09-10) Odadi, Wilfred O.; Kimuyu, Duncan M.; Sensenig, Ryan L.; Veblen, Kari E.; Riginos, Corinna; Young, Truman P.
Prescribed burning is used in tropical savannas to improve habitat conditions for domestic and wild herbivores, but its effects on the ecological interactions between these herbivore guilds have never been assessed experimentally. Understanding such effects will contribute towards more informed management of both guilds in landscapes where they share habitats. We investigated the effects of burning on the nutritional outcomes for cattle sharing habitat with wildlife in a Kenyan savanna ecosystem. We compared forage availability and cattle forage and nutrient intake rates across burned and unburned areas cattle accessed exclusively, and those they shared with medium-sized wild ungulates, both with and without megaherbivores (elephants and giraffes). We performed these measurements in May 2013 (wet period, 2 months post-burning) and February 2014 (dry period, 11 months post-burning). Additionally, we monitored wildlife use of these areas. Prescribed burning enhanced cattle nutrition, but only in areas cattle did not share with wildlife. Shared foraging with wildlife reduced cattle forage and nutrient intake rates by 37–97% in burned areas (burns), but not in unburned areas; these reductions corresponded with reduced herbage availability in the shared burns. In May (the wet period), cattle met their nutrient intake requirements in burns, regardless of whether they were sharing these areas with wildlife. However, in February (the dry period), nutrient requirements were unmet or tended to be unmet in burns shared with wildlife; requirements were met or significantly exceeded in the unshared burns. Experimental exclusion of megaherbivores did not moderate these effects, suggesting that they were primarily caused by medium-sized wild ungulates which were highly attracted to burns. Synthesis and applications. Prescribed burning produces negative nutritional outcomes for cattle when sharing habitat with wild ungulates. Because these effects could negatively influence livestock–wildlife coexistence, burning should be applied prudently in such human-occupied savanna landscapes. Specifically, because unburned areas serve as refuge foraging areas during the dry season, interspersing burns with unburned areas could minimize fire-driven negative interactions between cattle and wild ungulates. Conversely, burning could be used to draw wildlife away from valuable cattle foraging areas, such as those near available water.
Evaluation of Plant Growth on Expanded Black Cotton Soil
(The Premier Publishers, 2018-02-01) Nyakach, Samwel; Owido, Seth; Onyando, Japheth
In aggregate hydroponics, the suitability of a particular medium is often guided by its physical properties. However these may not provide adequate evaluation. By growing a crop, the growth characteristics can also be used to guide medium preparation and selection. Tomatoes (Anna F1 variety) were grown in containers under a greenhouse and provided with equal amount of nutrient solution. The expanded black cotton soil was prepared by mixing with rice husk at a ratio of 90:10, fired at 750oC for 30 minutes and size reduced to various textures. The crops planted in the expanded clay aggregates performed better than the black cotton soil both in terms of stem elongation and enlargement due to improved drainage, nutrient flow and aeration conditions. The root length density was 25654 m m-3 in black cotton soil, being the highest and lowest in the coarse aggregates which had 9433 m m-3.
Heavy Metal Levels in Nakuru Town and the Surrounding Farmland Soils
(Egerton University, 2021-05) Kipruto, Misoi Simion
Heavy metals input in soils has been found to present a serious agro-environmental concerns in areas of intensive industrial and agricultural activities and Nakuru town and its surrounding farmland soil is not an exception. High input of heavy metals beyond the threshold limit values is a potential health hazard to plants, and even to animals and human beings through the food chain. The source of heavy metals in soil is primarily the parent rock material, however significant increases may occur through anthropogenic activities. The main objective of this study was to investigate the presence and levels of total and extractable selected heavy metals such as cadmium, chromium, copper, nickel, lead, and zinc in soils of Nakuru town and the surrounding farmlands busing the flame atomic absorption spectrometric technique. The status of some soil chemical properties such as pH, percentage organic carbon and cation exchange capacity were also investigated using stipulated standard methods. The sampling was done randomly in triplicate from 8 sites within Nakuru town and 8 sites in the surrounding farmlands. The data obtained from the experimental analysis were subjected to both descriptive and inferential statistics. The study revealed the presence of heavy metals in Nakuru town and its surrounding farmland soils but they were in very low levels as compared to world health organization maximum permissible levels. The heavy metal concentrations levels were found to correlate(P≤ 0.05) with the chemical properties either positively or negatively. The levels of heavy metals in Nakuru town soils were observed to be generally higher compared to the levels in the surrounding farmland soils, industrial and domestic emissions being the main contributing factor. The levels of extractable metals in Nakuru town soils had an effect on the levels of extractable metals in the surrounding farmland. It can be concluded from this study that there is no risk of heavy metal toxicity in the study area but accumulation of these heavy metals over time in soil can exceed the stipulated levels hence posing a potential hazard.
Mapping the trends of forest cover change and associated drivers in Mau Forest, Kenya
(Science Direct, 2021-08-01) Jebiwott, Alice; Ogendi, George Morara; Agbeja, Busuyi Olasina; Alo, Abiodun Akintunde; Kibet, Ronald
Mau Forest in the Rift Valley in Kenya is the largest of the five major water towers in the country and also the largest indigenous montane forest in Eastern Africa. As such, the forest is an important natural resource base not only to the local economy but to the East African region at large. In spite of this, the forest has been highly degraded owing to immense anthropogenic pressure from the forest surrounding communities. The aim of this study was to assess the trends in forest cover and the driving forces leading to its change. Landsat TM images of 1984 and 1995, ETM+ of 2008, and OLI/TIRS of 2020 were used to depict the trend in forest cover for the period between 1984 and 2020. Focus Group Discussions (FGD) and in-depth interviews were also used to get the perceptions and experiences of the local people regarding the trend in forest cover and the associated driving forces. The results from the qualitative data were integrated with those of remote sensing for assessment of trend in forest cover. The study findings indicate a decline of 25.2% of forest cover within the Mau Forest complex in a period four years shy of four decades, amounting to approximately 699 km2 of tree cover. This trend was fueled by an increasing demand for agricultural land where farmlands increased by 69.9%, as well as logging-legal or illegal-where grassland area increased by 37.2%. Three major drivers of forest cover change identified by the participants include human settlements, logging and expansion of farmlands. We recommend that forest policymakers and managers involve the local community, as the main stakeholders, in all levels of decision making and management so as to promote sustainable use of forest resources and improved management of the forest.
Analysis of Temporal Drought Characteristic Using SPI Drought Index Based on Rainfall Data in Laikipia West Sub-County, Kenya
(Scientific Research, 2017-01-01) Karanja, Amon; Ondimu, Kennedy; Recha, Charles
Severe drought has affected Kenya in the past decades reducing crop yields leaving millions of people in dire need of food. Drought cycle in Kenya has reduced increasing drought frequency in the recent decades. This study assessed drought characteristics in Laikipia West sub-County which lies in a region classified as arid and semi arid. The specific objective of the study was to analyze seasonal and annual drought characteristics in Laikipia West sub-County between 1984 and 2014. The study adopted documentary review design in the data collection. Standard Precipitation Index was used during the data analysis process. The drought years identified in Laikipia West sub-County were: 1984, 1985, 1987, 1991, 1995, 1999, 2000, 2005, 2008 and 2009. The seasonal drought events shows that for the period under study Laikipia West sub-County has never experience drought during the MAM and OND seasons in the same year. This explains the importance of seasonal climate forecast to crop farmers. The study also established that the average drought cycle in the study area is 3 years. The study recommends construction of mega water reservoirs which could collect water during the wet season to be utilized during the dry seasons. The study also recommends channeling of drought information through the government agencies at the beginning of every season.
Effect of Land Use on Leaf Litter Decomposition in Upper Mara Streams, Kenya
(Egerton University, 2018-01-18) Tsisiche, A.; M’merimba, C.; Mbaka, J. G.
Modification of riparian vegetation via land use change alters leaf litter processing rates in streams. This study aimed at investigating the effect of land use change from forestry to agriculture on leaf litter decomposition in the upper Mara River catchment, Kenya. The study involved collecting, drying and weighing leaves of Eucalyptus saligna (exotic) and Macrocalyx neubotonia (native). About 6g of each leaf species was enclosed in litter bags measuring 11 x 11cm and mesh size of 10mm. The bags were exposed randomly in six streams; three draining agricultural and three draining indigenous forests. They were later retrieved at intervals of 0, 1,3,7,14,28 and 48 days, dried and weighed. The difference in processing rates of Eucalyptus leaves were statistically not significant (insert test and statistics) between streams draining indigenous forest (mean -k = 0.039±0.009, pooleddata) and streams draining agricultural areas decaying Macrocalyx leaves were –k = 0.095±0.005 in streams draining agricultural areasand k=0.062±0.01 for streams draining indigenous forest. The two values differed significantly (t = 2.892, d.f=4, p= < 0.05). Significant differences in processing rates were also evident between Eucalyptus and Macrocalyx leaves in streams draining indigenous and agricultural forests respectively (ttest, p<0.05). It would take 63 and 69 days for 90% of leaves of Eucalyptus to be processed in agricultural and forested streams respectively whilst Macrocalyx leaves would take 24 and 53 days. Processing rates for the two leaves were generally higher in agricultural streams than in forested streams most probably due to higher nutrients especially Phosphate concentration arising from agricultural land. In all the study streams SRP had significant correlation with decay rates for both species. Significant differences in processing rates observed between the two leave species could be attributed to differences in leave toughness and the presence of inhibitory compounds in eucalypts. The findings of this study suggest that land use change interacts with change in the composition of riparian tree species to influence decomposition ratesof leaf litter in streams. This has implications on theEgerton J. Sci. & Technol. Volume 16:functional organization of shredders and nutrient cycling in streams. This study confirms that land use activity has an effect on litter decomposition rates in Upper Mara catchment streams. However Eucalyptus decomposition did not respond to change in land use activity because of its poor quality which masks the land use effect.
VEGETATION, WILDLIFE AND LIVESTOCK RESPONSES TO PLANNED GRAZING MANAGEMENT IN AN AFRICAN PASTORAL LANDSCAPE: PLANNED GRAZING ENHANCES PASTORAL RANGELAND PRODUCTIVITY
(John Wiley and Sons Ltd, 2017-02-22) Odadi, Wilfred; Fargione, Joe; Rubenstein, Daniel
Rangelands are vital for wildlife conservation and socio-economic well-being, but many face widespread degradation due in part to poor grazing management practices. Planned grazing management, typically involving time-controlled rotational livestock grazing, is widely touted as a tool for promoting sustainable rangelands. However, real-world assessments of its efficacy have been lacking in communal pastoral landscapes globally, and especially in Africa. We performed landscape-scale assessment of the effects of planned grazing on selected vegetation, wildlife and cattle attributes across wide-ranging communally managed pastoral rangelands in northern Kenya. We found that planned grazing enhanced vegetation condition through a 17% increase in normalized difference vegetation index (NDVI), 45-234% increases in herbaceous vegetation foliar cover, species richness and diversity, and a 70% reduction in plant basal gap. In addition, planned grazing increased the presence (44%) and species richness (53%) of wild ungulates, and improved cattle weight gain (>71%) during dry periods when cattle were in relatively poor condition. These changes occurred relatively rapidly (within 5 years) and despite grazing incursion incidents and higher livestock stocking rates in planned grazing areas. These results demonstrate, for the first time in Africa, the positive effects of planned grazing implementation in communal pastoral rangelands. These improvements can have broad implications for biodiversity conservation and pastoral livelihoods.
Effects of Climate Variability on Foraging Behaviour of Bees: A Case Study of Marigat and Ratat locations in Baringo County, Kenya
(Elsevier, 2019-05-17) Haron, Akala; Makindi, Stanley; Moses, Esilaba
Beekeeping is among the livelihood diversification strategies likely affected by climate variability. The variation in temperature and rainfall influence forage phenology impacting on honey production in arid and semi-arid lands (ASALs) in Kenya. The study focused on the relationship between rainfall variability on honey production among the pastoral communities. Rainfall variability was exhibited in the study area and in some circumstances drought was experienced annually. On average, 19 plant species were recorded that the bees prefer in the study area. Rainfall variability has significant positive correlation (r=0.423;p=0.001) on the effect on plant phenology thus altering flowering periods of many of the forage plants, changing the foraging behaviour of bees resulting to decrease in honey production. The findings of this study indicate that variation in rainfall has had an adverse effect on honey production and therefore there is need to incorporate land management strategies that will improve honey production in ASALs for sustainable livelihoods among pastoral communities in the context of climate variability.

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