Department of Natural Resources
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Item Fishing power of conventionally harvested wetland baitworms compared to black soldier fly larvae as alternative baits in tropical artisanal hook fishery(2018) Kihia, C. M.; Gitonga, L. M.; Tembo, J. E.; Kanyeki, E.; Munguti, J.; Muli, B.Extensive and intensive, harvesting of earthworms and polychaetes from wetland substrate, for artisanal hook fishery, affect structural and functional integrity of these critical habitats. Cultured Black Soldier Fly larvae (BSF, Hermitia illucens), are suggested as sustainable alternatives. This study compares bait and landed fish properties of wild earthworm (Eisinia sp) and polychaete (Marphysa mossambica), with cultured BSF larvae as bait, in hook fishery. Participating fishers, were supplied with known quantity of bait, and the duration and quantity of fish obtained, monitored. Hook casting, attractiveness and killing power, as well as fish quality and quantity, were computed and compared among sites and bait. Results reveal significant (P<0.05) differences in bait and landed fish properties. Lower bait casting (8.8%), but higher attractiveness (0.96) and killing power (55%), were obtained using polychaete in marine habitats, than either earthworms or BSF. Similarly, higher fish landings s (0.59 kg.hr-1), were obtained using polychaete, than comparable BSF or earthworm (<0.1 kg. hr-1. We surmise that wild baitworms, are easier to handle, attract and land more fish, leading to higher variety and abundant landed fish, than cultured BSF larvae. Lower performance of BSF is attributed to; poor response of target fish to imprinted physical and chemical attributes of the bait. This may imply that fishers, have limited justification for substituting cultured BSF, with conventional wild baitworm in artisanal fishery. Further elucidation of drivers to bait choice and performance coupled with improvement in cultured bait quality might, provide sustainable solutions.Item Globalization and Biodiversity Conservation Problems: Polycentric REDD+ Solutions(MDPI, 2019-02-19) Githiru, Mwangi; Njambuya, Josephine W.Noise barriers are the most widespread solution to mitigate noise produced by the continuous growth of vehicular traffic, thus reducing the large number of people exposed to it and avoiding unpleasant effects on health. However, conventional noise barriers present the well-known issues related to the diffraction at the edges which reduces the net insertion loss, to the reflection of sound energy in the opposite direction, and to the complaints of citizens due to the reduction of field of view, natural light, and air flow. In order to avoid these shortcomings and maximize noise abatement, recent research has moved toward the development of sonic crystals as noise barriers. A previous review found in the literature was focused on the theoretical aspects of the propagation of sound through crystals. The present work on the other hand reviews the latest studies concerning the practical application of sonic crystal as noise barriers, especially for road traffic noise mitigation. The paper explores and compares the latest developments reported in the scientific literature, focused on integrating Bragg’s law properties with other mitigation effects such as hollow scatterers, wooden or recycled materials, or porous coating. These solutions could increase the insertion loss and frequency band gap, while inserting the noise mitigation action in a green and circular economy. The pros and cons of sonic crystal barriers will also be discussed, with the aim of finding the best solution that is actually viable, as well as stimulating future research on the aspects requiring improvement.Item 290IMPACTS OF COMMUNITY ACTIVITIES ON ENVIRONMENTAL RESOURCES: THE POTENTIAL FOR DEVELOPING PAYMENT SCHEMES FOR ENVIRONMENTAL SERVICES(VDM Dr Muller Gmbh and co, 2011-01) Kiptum, Andrew; Kipkoech, Anderson; Omondi, Humhprey; Adano, Wario R.; Osano, Odipo; iryahwaho, Byamukama B; Agasha, AnnahNatural resources have continued to be degraded largely because of lack of well-defined property rights, population pressure, high levels of poverty and the lack of proper understanding of deleterious impacts of human activities on forest and watershed resources depletion. The social cost of exploiting the resources is larger than the private benefits and individuals have incentives to excessively extract natural resources at an expense of conservation. This study considers the socio-economic aspect, farm size and activities, water availability, the distance of the agricultural activities to the edge of the forest and riverbank and agricultural management practices employed by the population in Mt. Elgon District of Western Kenya. A proxy price was obtained using hypothetical structured question on willingness to pay and willingness to accept. The sample of 236 households was used to obtain data. Field surveys, structured questionnaires, interviews with key informants, and review of secondary sources were the main tools used for data collection. Statistical package for social science (SPSS) and Excel was the main software for data analysis. The results reveal average household of 8 persons, with most households living below poverty threshold (one dollar per person per day) and on average farm size holdings of 3.105 acres per household. The results also show that most farms are within the edge of the forest and riverbank at a distance ranging about 8 km and 1 km, respectively. More than 50% of the sample population do not practice water and soil management, resulting in reduced physical properties of the water such as volume of water, turbidity, taste and smell to undesired state. The contingent value of ecosystem pricing from willingness to pay (WTP) and willingness to accept (WTA) exercise yield mean prices of the responses Ksh. 728.82 and Ksh. 6,631.44, respectively. In conclusion, the household activities of the community in Mt Elgon landscape encourage resource depletion. Therefore, adoption of sustainable agriculture and ecosystem management that consider conservation of natural resource in order to have desired qualities of the ecosystem products and to reduce the costs to the population living downstream and around are recommended. There is need to educate the local population living around the forest and watershed areas to practice sound farming practices.Item Floristic Composition, Affinities and Plant Formations in Tropical Forests: A Case Study of Mau Forests in Kenya(International Journal of Agriculture and Forestry, 2015) Mugo, Mware J.; Mutiso, Festus M.; Cheboiwo, Joshua; Sang, Francis; Tarus, George K.In the past, Mau forest complex has faced a wide range of disturbances majorly anthropogenic in nature. In this paper, the ecosystem floristic composition, richness, diversity and affinities are evaluated. Diameter at breast height (dbh) was measured and types and levels of disturbances recorded in plots, dbh of saplings measured in subplots and seedlings counted in microplots. To obtain the floristic composition and richness, we categorized species based on their families, development stages and life forms. Shannon-Wiener information index (H’) and Jaccard (JIA) and Sorensen(S) similarity indices were used to evaluate the species diversity and similarity respectively Trees, recorded belonged to 52 species, 45 genera and 31 families for seedlings; 43 species, 38 genera and 29 families for saplings and 55 species, 48 genera and 31 families for mature trees. The most species-rich family was rutaceae with six species followed by moraceae and flacourtiaceae with five. Western Kedowa had the highest diversity. Northern and Western Kedowa were the most similar pairs. Past and present disturbances and aggressive proliferation of the invasive; Trichocladus ellipticus (Eckl. and Zeyh) are the main causes of low species diversity and richness. In conclusion, the sites are floristically dissimilar but at varying degrees. The post-disturbance recovery on different sites is following different trajectory successional pathways. We recommend that the on-going disturbances should be curtailed to promote regeneration and successful recruitment of non-pioneer species.Item Influence of Adherence to Quality Management System Standards on Access to Water and Sanitation Services in Kenya(IOSR Journal Of Humanities And Social Science, 2018-02) N, Edward; B, Patrick; Ng’ang’a, Stephen I.In Kenya, over 3,100 children die annually for using unsafe water and poor sanitation. In the 2015/2016 financial year, access to water in Kenya stood at 54% for urban and 51% for rural areas. This low access to water and sanitation services could be as a result of the management practices in the water services providers. Previous studies have revealed the unsuccessful attempts to improve access of water and sanitation services through privatization and structural reforms in the water sector. These studies did not assess how management practices such as the quality management system can enhance access to water and sanitation services. The objective of the study was to determine the influence of the level of adherence to quality management system standards on access to water and sanitation services. The study adopted a combination of descriptive and explanatory research designs. The target population consisted of the 86 water service providers in Kenya. The sample comprised 70 water service providers who were selected using the stratified random sampling. The respondents of the study included the 70 general managers of the selected water service providers. Primary data was collected by the use of questionnaires. Secondary data was obtained from the 2016 /2017 WASREB report. The instruments were tested for validity and reliability through the content validity index (CVI=0.833) and the Cronbach alpha’s internal consistency index (a=0.773) for reliability. The study found that thelevel of adherence to quality management system standards significantly influenced the access to water and a sanitation service in Kenya (t=15.7, p<0.05).The study recommended that the management of the water service providers should strengthen the level of adherence to quality management system standards to enhance access to water and sanitation services to the members of the public.Item PCBs in fish and their cestode parasites in Lake Victoria(Environ Monit Assess, 2016) Okoth, E. Oyoo; Otiego, J. Oluoch; Chemoiwa, E. J.; Ngugi, C. C.; Omutange, E. S.; Ngure, V.; Opiyo, M. A.Polychlorinatedbiphenyls(PCBs)areclassified as persistent organic pollutants (POPs) regulated by the Stockholm Convention (2001). Although their production and use was stopped almost three decades ago, PCBs are environmental persistent, toxic, and bioaccumulate in biota. We assessed the levels of 7 PCB congeners (IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) in sediment and fish (Oreochromis niloticus, Lates niloticus, and Rastrineobola argentea) and evaluated the potential of cestode fish endoparasite (Monobothrioides sp., Proteocephalaus sp., and Ligula intestinalis) as biomonitorsofPCBsinLakeVictoria,Kenya.Themedian concentrationof Σ7PCBsinsedimentsandfishwere2.2– 96.3 μg/kg dw and 300–3,000 μg/kg lw, respectively. At all the sampling sites, CB138, CB153, and CB180 were the dominant PCB congeners in sediment and fish samples. Compared to the muscle of the piscine host, Proteocephalaus sp. (infecting L. niloticus) biomagnified PCBs ×6–14 while Monobothrioides sp. (infecting O. niloticus) biomagnified PCBs ×4–8. Meanwhile, L. intestinalis (infecting R. argentea) biomagnified PCBs ×8–16 compared to the muscle of unparasitized fish. We demonstrate the occurrence of moderate to high levels of PCB in sediments and fish in Lake Victoria. We also provide evidence that fish parasites bioaccumulate higher levels of PCBs than their piscine hosts and therefore provide apromising biomonitor of PCBs. Weurgefurther a long-term study to validate the use of the above cestode fish parasites as biomonitoring tools for PCBs.Item Tree resprout dynamics following fire depend on herbivory by wild ungulate herbivores(Journal of Ecology, 2019-04) Kimuyu, Duncan M.; LaMalfa, Eric M.; Sensenig, Ryan L.; Young, Truman P.; Riginos, Corinna; Veblen, Kari E.1. Savanna tree cover is dynamic due to disturbances such as fire and herbivory. Frequent fires can limit a key demographic transition from sapling to adult height classes in savanna trees. Saplings may be caught in a ‘fire trap’, wherein individuals repeatedly resprout following fire top-kill events. Saplings only rarely escape the cycle by attaining a fire-resistant height (e.g. taller than the minimum scorch height) during fire-free intervals. 2. Large mammalian herbivores also may trap trees in shorter size classes. Browsing herbivores directly limit sapling height, while grazing herbivores such as cattle facilitate sapling growth indirectly via grass removal. Experimental studies investigating how meso-wildlife, megaherbivores and domestic livestock affect height of resprouts following fire are rare, but necessary for fully understanding how herbivory may reinforce (or counteract) the fire trap. In our study system, interactive fire–herbivore effects on transitions from sapling (<1 m) to adult tree (>1 m) height classes may be further influenced by plant defences, such as symbiotic ants. 3. We used the Kenya Long-term Exclosure Experiment (KLEE) to investigate how post‐fire resprout size of a widespread monodominant East African tree, Acacia drepanolobium was influenced by (a) herbivory by different combinations of cattle, meso-wildlife (15–1,000 kg) and megaherbivores (>1,000 kg) and (b) the presence of acacia–ant mutualists that confer tree defences. We sampled height, stem length and ant occupancy of resprouts exposed to different herbivore combinations before and after controlled burns. 4. Resprout height of saplings that were short prior to fire (<1 m) was reduced primarily by meso-wildlife. Negative effects of elephants on post-fire resprout height increased with pre-fire tree size, suggesting that resprouts of the tallest trees (with the greatest potential to escape the fire trap cycle) were preferentially browsed and reduced in height by elephants. There were no significant cattle effects. 5. Synthesis. We provide experimental evidence for two potential pathways through which large herbivores exert control over sapling escape from the fire trap: (a) post-fire meso-wildlife browsing of short (<1 m) resprouts and (b) elephant browsing of the largest size class of resprouts, which would otherwise be most likely to escape the fire trapItem Sustainable Utilization of Wetlands Resources in Selected Areas of Nyamira County, Kenya(Research journali’s Journal of Geography, 2015) Huho, Julius M.; Angawa, Francis O.; Nyaboga, John OgandaResearches on wetland utilization in Kenya focus more on wetlands located in the ASALs and Lowland areas giving less emphasis to those in high agricultural potential highland areas. This paper examined the utilization of Sironga and Nyabomite wetlands resources in the high potential agricultural areas of Nyamira County. The specific objective established the resources and their uses. Purposive sampling was used in selecting study areas and key informants. Simple random sampling was used in selecting household heads. Data was obtained through the administration of 126 questionnaires of which 115 was used for analysis. Quantitative data was analyzed using descriptive statistics. Data was presented using statistical tables, percentages and photographs. The common wetland resources utilization practices in the area are brick making activities and crop production. Traditionally, the wetlands provided place for conducting rituals and ceremonies. The following recommendations ought to be prioritized: identification of key stakeholders and assessment of their interests; emphasis on afforestation of the wetlands with trees that are friendly to the environment and adoption of alternative sources of livelihoods. The recommendations of this paper are useful in the sustainable utilization of wetland resources in Nyamira County and other high agricultural potential areas. Keywords: Biodiversity, conservation, livelihoods, utilization, wetland resourcesItem Dietary administration of probiotics modulates non-specific immunity and gut microbiota of Nile tilapia (Oreochromis niloticus) cultured in low input ponds(International Journal of Veterinary Science and Medicine, 2019) Ngugi, Charles C.; Jumbe, James; Opiyo, Mary A.; Charo-Karisa, HarrisonItem The Role of Selected Environmental Factors on the Regeneration of (Ocotea usambarensis ) in Mount Kenya Forest, Kenya(International Journal of Agriculture, Environment and Bioresearch, 2018) E., Githae; G.M, Nduru; A.M., Magana; J.N, RithaaDespites the propagation efforts, density of Ocotea usambarensis has continued to diminish in the southern slopes of Mount Kenya. The species which is native in the montane forest is seldom on farm and found as remnant species. The concerns on the role of environmental factors and how they influence regeneration of Ocotea usambarensis have been sidelined resulting to lack of adequate information that would be required for modeling how to reestablish Ocotea usambarensis. This study therefore examined the role of Rainfall, Humidity, Temperature, wind speed and soil characteristics on regeneration of Ocotea usambarensis. The study was conducted in the southern slopes of Mount Kenya forest. Data on environmental factors, regeneration status and species diversity were analyzed using regression, Pearson Correlation, Shannon- Wiener (H ) Index and Simpson (D) Index. The regeneration status was “J” shaped with mature trees more than regenerants. The relationship was strong (R2 = 78%) between humidity and rainfall (P < 0.05) while for temperature and wind speed were insignificant. The correlation between soil compositions varied significantly (P< 0.05). The soil pH positively correlated with soil nutrients while Cation exchanges capacity negatively correlated with potassium and silicon. It was observed that Diospyros abyssinica was growing in close association with O. usambarensis playing the role of nurse species. With the absence of seedlings in most of the sites and the limiting environmental factors, promotion of vegetative propagation and enrichment planting would enhance conservation and restoration of the species in Mt. Kenya forest. The high levels of soil nutrients and Cation exchange capacity in forest soils indicated the need to maintain them high on farm for optimal growth rate. Enhancing optimal environmental conditions for growth would enhance conservation and restoration of the Ocotea usambarensis