The study aimed to develop a customized Data Governance Maturity Model (DGMM) for the Ministry of Defence (MoD) in Kenya to address data governance challenges in military settings. Current frameworks lack specific req...The study aimed to develop a customized Data Governance Maturity Model (DGMM) for the Ministry of Defence (MoD) in Kenya to address data governance challenges in military settings. Current frameworks lack specific requirements for the defence industry. The model uses Key Performance Indicators (KPIs) to enhance data governance procedures. Design Science Research guided the study, using qualitative and quantitative methods to gather data from MoD personnel. Major deficiencies were found in data integration, quality control, and adherence to data security regulations. The DGMM helps the MOD improve personnel, procedures, technology, and organizational elements related to data management. The model was tested against ISO/IEC 38500 and recommended for use in other government sectors with similar data governance issues. The DGMM has the potential to enhance data management efficiency, security, and compliance in the MOD and guide further research in military data governance.展开更多
On a sunny afternoon,Nelly Wahome mounted a smartphone on a tripod to film one of Mombasa’s tourist hotspots-Nyali Resort,a popular northern beach resort in Kenya.Wahome,25,shared the latest video clip via her TikTok...On a sunny afternoon,Nelly Wahome mounted a smartphone on a tripod to film one of Mombasa’s tourist hotspots-Nyali Resort,a popular northern beach resort in Kenya.Wahome,25,shared the latest video clip via her TikTok handle in a quest to enchant her followers with the day’s tourism scene along Nyali’s coastline.Within a few hours of uploading,her content attracted hundreds of views.展开更多
Kenya is set to become the first country in Africa to start exporting avocados to China, once a recent agreement signed between the two countries comes into effect. The deal is expected to lead to the export of 40 per...Kenya is set to become the first country in Africa to start exporting avocados to China, once a recent agreement signed between the two countries comes into effect. The deal is expected to lead to the export of 40 percent of the country's avocado produce to China, according to the Kenya Plant Health Inspectorate Service (KEPHIS), and also opens the door for the export of other horticultural crops such as flowers, French beans, baby corn, broccoli and sugar snaps.展开更多
The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted ...The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted on Afromontane ecosystems have compared the altitudinal patterns of small mammal diversity. We investigated the species diversity and abundance of non-volant small mammals(hereafter ‘small mammals')on Mt. Kenya, the second tallest mountain in Africa,using a standard sampling scheme. Nine sampling transects were established at intervals of 200 m on the eastern(Chogoria) and western(Sirimon) slopes.A total of 1 905 individuals representing 25 species of small mammals were trapped after 12 240 trap-nights.Abundance was highest at mid-elevations on both slopes.However, species richness and their distribution patterns differed between the two slopes. More species were recorded on Chogoria(24) than on Sirimon(17). On Chogoria, species richness was higher at mid-high elevations, with a peak at mid-elevation(2 800 m a.s.l.),whereas species richness showed little variation on the Sirimon slope. These results indicate that patterns of species diversity can differ between slopes on the same mountain. In addition, we extensively reviewed literature on Mt. Kenya's mammals and compiled a comprehensive checklist of 76 mammalian species. However, additional research is required to improve our understanding of smal mammal diversity in mountain habitats in Africa.展开更多
The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by ...The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by the Massai people in the east side of Amboseli National Park in Kenya. The data were collected from grasslands designated into four types： （1） grassland from previous Massai settlements that had been abandoned for over twenty years; （2） grassland excluded from livestock grazing for eight years; （3） a dry season grazing area; and （4） a continuous grazing area where grazing occurred throughout all seasons. Collected data included grass species composition, grass height, inter-tuft distance, standing grass biomass and soil characteristics. The results indicated that continuous grazing area in semiarid rangelands exhibited loss of vegetation with negative, long-term effects on grass functional qualities and forage production, whereas grassland that used traditional Maasai grazing methods showed efficiency and desirable effects on the rangelands. The results also showed that abandoned homestead sites, though degraded, were important nutrient reservoirs.展开更多
Rangeland degradation is a serious problem throughout sub-Saharan Africa and its restoration is a challenge for the management of arid and semi-arid areas. In Lake Baringo Basin of Kenya, communities and individual fa...Rangeland degradation is a serious problem throughout sub-Saharan Africa and its restoration is a challenge for the management of arid and semi-arid areas. In Lake Baringo Basin of Kenya, communities and individual farmers are restoring indigenous vegetation inside enclosures in an effort to combat severe land degradation and address their livelihood problems. This study evaluated the impact of enclosure management on soil properties and microbial biomass, being key indicators of soil ecosystem health. Six reseeded communal enclosures using soil embankments as water-harvesting structures and strictly regulated access were selected, varying in age from 13 to 23 years. In six private enclosures, ranging from 3 to 17 years in age, individual farmers emulated the communal enclosure strategy and restored areas for their exclusive use. Significant decreases in bulk density, and increases in the soil organic carbon, total nitrogen and microbial biomass contents and stocks were found in the enclosures as compared with the degraded open rangeland. In the private enclosures, the impact of rehabilitation on the soil quality was variable, and soil quality was in general lower than that obtained under communal management. The significant increase of absolute stocks of carbon, nitrogen and microbial biomass compared to the degraded open rangeland indicates the potential for the restoration of soil quality through range rehabilitation. Over-sowing with indigenous legume fodder species could improve total nitrogen content in the soil and nutritional value of the pastures as well.展开更多
The Kenya Rift Valley is relatively prone to underground erosion ground fissures and associated disasters,which gravely hinder local engineering construction and economic development.In this research,we performed fiel...The Kenya Rift Valley is relatively prone to underground erosion ground fissures and associated disasters,which gravely hinder local engineering construction and economic development.In this research,we performed field and experimental studies on ground fissures in the Kenya Rift Valley area,and determined the structural characteristics of underground erosion fissures.Based on a geological survey of the area,we generalized a geological model for typical ground fissures and reproduced the intermediate process of ground fissure propagation using a large-scale physical model test.Further,the development process of underground erosion fissures were categorized into four stages:uniform infiltration,preferential infiltration,cavity expansion,and collapse formation stages.During the development of underground erosion fissures,water content was distributed symmetrically along the fissures,and these fissures acted as the primary infiltration paths of water.When the ground collapsed,the increase in negative pore water pressure was greater,whereas the increase in positive pore water pressure was less in the shallow soil;moreover,in the deep soil,the increase in positive pore water pressure was greater than that of negative pore water pressure.Additionally,the earth pressure increment initially increased and then decreased with the development of erosion.During underground erosion collapse,the water content and pore water pressure appeared to increase and decrease rapidly.These results can be employed to predict the occurrence of underground erosion ground fissures and the resulting soil collapse.展开更多
Emergence and re-emergence of infectious diseases of wildlife origin have led pre-emptive pathogen surveillances in animals to be a public health priority.Rodents and shrews are among the most numerically abundant ver...Emergence and re-emergence of infectious diseases of wildlife origin have led pre-emptive pathogen surveillances in animals to be a public health priority.Rodents and shrews are among the most numerically abundant vertebrate taxa and are known as natural hosts of important zoonotic viruses.Many surveillance programs focused more on RNA viruses.In comparison,much less is known about DNA viruses harbored by these small mammals.To fill this knowledge gap,tissue specimens of 232 animals including 226 rodents,five shrews and one hedgehog were collected from 5 counties in Kenya and tested for the presence of DNA viruses belonging to 7 viral families by PCR.Diverse DNA sequences of adenoviruses,adeno-associated viruses,herpesviruses and polyomaviruses were detected.Phylogenetic analyses revealed that most of these viruses showed distinction from previously described viruses and formed new clusters.Furthermore,this is the first report of the discovery and full-length genome characterization of a polyomavirus in Lemniscomys species.This novel polyomavirus,named Ls Py V KY187,has less than 60%amino acid sequence identity to the most related Glis glis polyomavirus 1 and Sciurus carolinensis polyomavirus 1 in both large and small T-antigen proteins and thus can be putatively allocated to a novel species within Betapolyomavirus.Our findings help us better understand the genetic diversity of DNA viruses in rodent and shrew populations in Kenya and provide new insights into the evolution of those DNA viruses in their small mammal reservoirs.It demonstrates the necessity of ongoing pathogen discovery studies targeting rodent-borne viruses in East Africa.展开更多
Kenya has a rich mammalian fauna. We reviewed recently published books and papers including the six volumes of Mammals of Africa to develop an up-to-date annotated checklist of all mammals recorded from Kenya. A total...Kenya has a rich mammalian fauna. We reviewed recently published books and papers including the six volumes of Mammals of Africa to develop an up-to-date annotated checklist of all mammals recorded from Kenya. A total of 390 species have been identified in the country, including 106 species of rodents,104 species of bats, 63 species of even-toed ungulates(including whales and dolphins), 36 species of insectivores and carnivores, 19 species of primates,five species of elephant shrews, four species of hyraxes and odd-toed ungulates, three species of afrosoricids, pangolins, and hares, and one species of aardvark, elephant, sirenian and hedgehog. The number of species in this checklist is expected to increase with additional surveys and as the taxonomic status of small mammals(e.g., bats, shrews and rodents) becomes better understood.展开更多
The aim of this study was to identify Aspergillus species isolated from maize kernels and soils of maize fields of Nandi County using macro and micro morphological characteristics. A cross sectional research design wa...The aim of this study was to identify Aspergillus species isolated from maize kernels and soils of maize fields of Nandi County using macro and micro morphological characteristics. A cross sectional research design was used in the study and purposive sampling was employed to determine districts of Nandi County and sub locations where sampling was done. This study was part of a larger project whose aim was to survey aflatoxin exposure in the maize value chain. Aspergillus species were isolated from maize and soil samples using quarter strength potato dextrose agar and modified Rose Bengal agar respectively. Pure cultures of the isolates were sub cultured and transferred onto differential media;malt extract agar, czapek yeast extract agar and czapek dox agar for species identification using macro morphological characteristics. Fungal slides were prepared from pure cultures on potato dextrose agar media after three days to identify micro morphological characteristics. Based on morphological characteristics, seven sections of Aspergillus namely: Flavi, Fumigati, Nigri, Circumdati, Clavati, Nidulantes and Candidi were identified. Aspergillus section Flavi was the most predominant with 57% followed by section Nigri with 27% from maize and 58% of section Flavi followed by 26% of section Nigri from the soil across the three locations. Aspergillus sections Nidulantes and Candidi were rare and only recovered from the soil samples of Kaptumo location. All the Aspergillius flavus that formed sclerotia both from the soils or maize kernels were of the L strains. In conclusion Aspergillus section Flavi was most frequent during the isolation process and dominated with Aspergillus flavus from both the maize and soil. Morphological characteristics remain the primary tool for detection and identification of Aspergillus species. The significance for high incidence of Aspergillus section Flavi is in regard to their aflatoxin production profiles that poses a health threat to the community and it is of public health concern. Morphological characteristics as a primary tool for Aspergillus identification should be embraced and more personnel with the knowledge are required since modern and faster techniques are scarce and expensive.展开更多
Ecological dynamics and faunal diversity documentation is normally conducted by direct observation and trapping of live animals. However,surveys of carnivore scat prey and surface bone remains, which are relatively in...Ecological dynamics and faunal diversity documentation is normally conducted by direct observation and trapping of live animals. However,surveys of carnivore scat prey and surface bone remains, which are relatively inexpensive, can provide complementary data that expand carnivore diet breadth and may improve accuracy regarding inferences of the ecological dynamics of a given ecosystem. We used this inexpensive method to document species diversity variation with elevation on the leeward(Sirimon) and windward(Chogoria)areas of Mt. Kenya. Bone and fecal specimens were opportunistically collected by walking 2 km in opposite directions from transect points selected at 200-m intervals along the elevational gradient of the study areas. We collected a total of 220 carnivore fecal and owl pellet specimens from both study sites, which were mainly deposited by the spotted hyena(Crocuta crocuta), leopard(Panthera pardus),serval(Leptailurus serval), genet(Genetta sp.), and Mackinder's Cape owl(Bubo capensis mackinderi).Serval scats were the most common, followed by those of the spotted hyena. Scats and bones were found at the lowest density at the lowest elevations,peaked at mid-higher elevations, and then declined at the highest elevations. Based on skeletal analysis only, there were more species in Sirimon(19) than in Chogoria(12). Small fauna(rodents to duiker size bovids) formed the bulk of the identified remains,representing 87.9% of the Sirimon fauna and 90.9% of the Chogoria fauna. The genus Otomys was the dominant prey of the owl and serval in both sites. Three giraffe teeth were found at 3 500 m a.s.l. in Chogoria on the edge of Lake El is, suggesting that it is an occasional visitor to such high elevations. This study underscores the value of fecal and bone surveys in understanding the diet and diversity of mammals in ecological ecosystems,but such surveys should be complemented with analysis of hairs found in scats to obtain a more complete list of carnivore prey at Mt. Kenya.展开更多
Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significan...Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significant source of protein, carbohydrates, and minerals especially for poor populations in the Kenya, it is said to be poor man’s meat. The aim of this study was to determine nutritional composition of newly bred ten cowpea lines and five varieties commonly grown in Eastern Kenya of Kitui, Machakos and Makueni counties to understand their potential utilization in curbing rising food and nutrition insecurity in arid and semi-arid lands ASALs and in any other food applications in Kenya. The experiment was arranged in Completely Randomized Design (CRD) whereby proximate composition and minerals were determined using standard AOAC and AACC methods and technological characteristics checked using modified methods used by other researchers. Collected data were subjected to Analysis of Variance (ANOVA) using SAS (2006) version 9.1, mean separation was done using Tukey’s Honestly Significant Difference (HSD) method at 5% level of significance. Cowpeas composition ranged from 12.28% - 13.35% for moisture content, 49.37% - 55.74% for total carbohydrates, 2.99% - 3.34% for crude ash, 0.13% - 0.81% for crude lipids, 23.37% - 29.70% for crude protein and 1.40% - 4.34% for crude fibers. Cowpea samples recorded highest percentage of essential amino acids (60.71%) and non-essential amino acids (39.29%). Minerals ranged from 1.97 - 2.69 mg/100g for calcium, 3.23 - 3.90 mg/100g for magnesium, 205.53 - 223.30 mg/100g for sodium, 0.80 - 1.23 mg/100g for zinc, 1071.15 - 1152.62 mg/100g for potassium and 0.62 - 1.06 mg/100g for phosphorus. For technological properties, lines absorbed water equivalent to their weights and they were comparable to varieties grown in the region. From the results it showed that cowpea line IT97K-1042-3, TEXAN PINKIYE, TX123, IT85F-867-5, IT82D-889-1 and IT82D-889 have desirable attributes such as high crude protein contents, good water absorption capacities and volumetric expansion. They compared well with existing K80 variety. These cowpea lines could possibly be bred and combined into a single cowpea line and further improved by breeders to have other good properties such as higher levels of water absorption during soaking hence reduced cooking times. Therefore, this work has shown that cowpea lines developed can be used as food security crop, industrial food applications and enriching foods of low protein like in complementary foods for healthy food supply in Eastern Kenya.展开更多
We describe the first genome isolation of Middle East respiratory syndrome coronavirus(MERS-CoV) in Kenya. This fatal zoonotic pathogen was first described in the Kingdom of Saudi Arabia in 2012. Epidemiological and m...We describe the first genome isolation of Middle East respiratory syndrome coronavirus(MERS-CoV) in Kenya. This fatal zoonotic pathogen was first described in the Kingdom of Saudi Arabia in 2012. Epidemiological and molecular evidence revealed zoonotic transmission from camels to humans and between humans. Currently, MERS-CoV is classified by the WHO as having high pandemic potential requiring greater surveillance. Previous studies of MERS-CoV in Kenya mainly focused on site-specific and archived camel and human serum samples for antibodies. We conducted active nationwide cross-sectional surveillance of camels and humans in Kenya, targeting both nasal swabs and plasma samples from 1,163 camels and 486 humans collected from January 2016 to June 2018. A total of 792 camel plasma samples were positive by ELISA. Seroprevalence increased with age, and the highest prevalence was observed in adult camels(82.37%, 95%confidence interval(CI) 79.50–84.91). More female camels were significantly seropositive(74.28%, 95% CI 71.14–77.19)than male camels(P \ 0.001)(53.74%, 95% CI 48.48–58.90). Only 11 camel nasal swabs were positive for MERS-CoV by reverse transcription-quantitative PCR. Phylogenetic analysis of whole genome sequences showed that Kenyan MERSCoV clustered within sub-clade C2, which is associated with the African clade, but did not contain signature deletions of orf4 b in African viruses. None of the human plasma screened contained neutralizing antibodies against MERS-CoV. This study confirms the geographically widespread occurrence of MERS-CoV in Kenyan camels. Further one-health surveillance approaches in camels, wildlife, and human populations are needed.展开更多
Bacterial wilt (BW) caused by Ralstonia solanacearum is one of the most damaging diseases of potato (Solanum tuberosum L.) in Kenya and worldwide. In Kenya, potato tuber yield losses due to BW infection are estimated...Bacterial wilt (BW) caused by Ralstonia solanacearum is one of the most damaging diseases of potato (Solanum tuberosum L.) in Kenya and worldwide. In Kenya, potato tuber yield losses due to BW infection are estimated at 50 ~ 100%. Low soil fertility is also one of the most important constraints limiting potato production in central Kenya highlands. Farmers tackle this problem through use of inorganic fertilisers and organic manures, both of which amend the soil environment to influence bacterial wilt development. Undecomposed organic manures can also introduce the pathogen into a clean field. Between short rains 1999 and 2000, 10 on-farm extension-researcher- farmer-designed and farmer-managed trials were done at Kianjuki catchment in Embu District. The objective was to use farmers?participatory research approach and select the most suitable organic and inorganic fertiliser combination(s) with lowest BWI and acceptable usable tuber yields, and also to demonstrate use of some components of integrated disease management methods in reduction of disease incidence and spread. Seven treatments were proposed, presented to the farmers for discussion and the most relevant four were selected for evaluation. A newly released potato variety 慉sante?was planted during the short rains 1999 and long rains 2000. BWI didn抰 result in significant differences between treatments but the tuber yields were significantly different in short rains of 1999 and 2000. During short rains 2000, both BWI and tuber yields and unusable tubers differed significantly between treatments. The results confirmed that well- decomposed manures or manures from pathogen-free areas can be used in combination with inorganic fertilisers to improve soil fertility and potato tuber yields in smallholder farms without influencing BWI. Use of certified seed tubers in pathogen free field and following recommended field sanitation measures resulted in apparently bacterial wilt free crop. Considering the high cost of inorganic fertiliser and its negative effects on the environment, reduced usage at half the recommended rates combined with half rates of FYM is feasible option friendly to the farmer, soil and environment. The interviewed farmers also ranked the option as the most appropriate combination for soil fertility improvement for potato production in smallholder farms.展开更多
Noise is any sound that causes physiological uneasiness to the ear. People in many environments today, especially urban ones, are exposed to such noise without realizing its potential danger to their healthy hearing. ...Noise is any sound that causes physiological uneasiness to the ear. People in many environments today, especially urban ones, are exposed to such noise without realizing its potential danger to their healthy hearing. This situation is largely contributed to by the little attention that most governments, especially in the developing countries, pay to noise as a pollution issue. This paper describes a study that aimed at measuring the noise levels at selected points in Nairobi’s CBD with a view to generate a noise map over the study area in addition to identifying areas of high noise intensity or noise hot spots. The study found that noise levels, on average, varied from 61 db to 78 db, increasing from the west to the east of the CBD, and emanated mainly from vehicular traffic;several noise hotspots were also identified, and they are located mainly to the east of the CBD. The paper concludes that although the study was not city-wide, the noise levels observed are high enough to warrant further research and action by the environmental authorities.展开更多
Groundwater samples were evaluated throughout Turkana County(Kenya,East Africa)while looking for drinking water sources.Some samples showed high concentrations of fluoride with values in the range of 0.15–5.87 mg/L.A...Groundwater samples were evaluated throughout Turkana County(Kenya,East Africa)while looking for drinking water sources.Some samples showed high concentrations of fluoride with values in the range of 0.15–5.87 mg/L.Almost 50%of the samples exceeded the WHO and Kenyan potable water standard guideline value of 1.5 mg/L for drinking water quality.The hydrogeochemical studies revealed that the dominant cation in water is Na^(+)and the dominant anion is HCO_(3)^(-)resulting in Na-HCO_(3) type of groundwater,followed by Ca/Mg-HCO_(3) or Na-SO_(4) and Na-Cl in a few cases.Speciation modelling revealed that the groundwater is undersaturated with respect to gypsum and anhydrite,mostly undersaturated with respect to fluorite(6 samples are at equilibrium),and supersaturated or at equilibrium with respect to calcite(CaCO_(3)).Precipitation of calcite favours the dissolution of F-rich minerals in the alkaline medium.Simultaneously,groundwater is enriched with sodium and bicarbonate,probably as a result of chemical weathering of Na-feldspar.Investigated groundwater can be presumably used for drinking purposes from 17 wells,but a detailed investigation of other trace element concentrations is necessary.展开更多
Dietary quality is vital in maintaining sound nutritional status. The ecological conditions thus influence the type of diets and their nutritional quality. The purpose of this study was to determine the trace element/...Dietary quality is vital in maintaining sound nutritional status. The ecological conditions thus influence the type of diets and their nutritional quality. The purpose of this study was to determine the trace element/mineral content of some of the commonly consumed diets in Machakos, Kitui, Makueni and Mwingi districts. Decorticated maize, beans and finger millet flour samples were purchased from the local markets. For each category, a total of ten samples were collected from each district. The samples were put in plastic bags, sealed and transported to the laboratory in the Institute of Nuclear Science & Technology, University of Nairobi for preparation and analysis. The cooking of the samples was carried out according to local traditional methods. In the decorticated samples, mean copper concentrations were observed to be below 20 μg·g-1;mean zinc concentrations ranged from 34 to 63 μg·g-1 and mean manganese concentrations were in a similar range of 34 to 78 μg·g-1. The mean iron concentrations were significantly high with a range of 161 μg·g-1 to 287 μg·g-1. A similar trend was observed in the beans where the mean copper concentrations varied from 11 to 33 μg·g-1, mean zinc concentrations ranged from a low value of 24 μg·g-1 to a high value of 35 μg·g-1, mean manganese concentrations varied from 33 μg·g-1 to 98 μg·g-1 and the mean iron concentrations ranged from 227 μg·g-1 to 647 μg·g-1. The cooked Muthokoi samples from Machakos district had relatively high mean trace element concentrations: manganese—109 μg·g-1;iron—280 μg·g-1;copper—19 μg·g-1;and zinc—41 μg·g-1. The only exception was mean iron concentrations which were extremely high in samples from Mwingi District where the concentrations varied from 73 μg·g-1 to 1597 μg·g-1. In finger millet flour, the mean manganese concentrations varied from 95 to 290 μg·g-1, whereas the mean iron concentrations ranged from 127 μg·g-1 to 259 μg·g-1. In contrast, the mean copper and zinc concentrations were low in comparison to the manganese and iron concentrations. As a whole, the mean copper concentrations in the diets are significantly low compared to the other three trace elements. However, the total content is not necessarily a reflection of the amount assimilated in the body. Finger millet was found to be an excellent source of manganese and iron whereas beans were observed to be good sources of iron. All the food crops were observed to poor sources of copper.展开更多
With 16 Yunnan tea tree varieties and 5 Kenya tea tree varieties as test materials,the differences in biochemical components between Yunnan and Kenya tea tree varieties were compared and analyzed.The results showed th...With 16 Yunnan tea tree varieties and 5 Kenya tea tree varieties as test materials,the differences in biochemical components between Yunnan and Kenya tea tree varieties were compared and analyzed.The results showed that the coefficients of variation of tea polyphenols,amino acids,caffeine,water extract,gallic acid(GA),catechin(C),epicatechin(EC),epicatechin gallate(ECG),epigallocatechin(EGC),epigallocatechin gallate(EGCG)and total catechins in Yunnan tea tree varieties were greater than those in Kenyan tea trees.The contents of tea polyphenols,amino acids,caffeine,water extract,C,EC,EGC,EGCG and total catechins in Yunnan tea tree varieties had no significant differences from those in Kenyan tea trees varieties(P>0.05),while there were significant differences in the contents of GA and ECG between Yunnan tea tree varieties and Kenya tea tree varieties(P<0.05).Therefore,it could be predicted that GA and ECG might be one of the main characteristics of the differences in biochemical components between Yunnan tea tree varieties and Kenyan tea tree varieties.The cluster analysis results showed that when the genetic distance was 15,the 21 tested tea varieties could be divided into three groups with obvious biochemical differences.展开更多
Groundwater yield in the Kenya Rift is highly unsustainable owing to geological variability.In this study,field hydraulic characterization was performed by using geoelectric approaches.The relations between electrical...Groundwater yield in the Kenya Rift is highly unsustainable owing to geological variability.In this study,field hydraulic characterization was performed by using geoelectric approaches.The relations between electrical-hydraulic(eh)conductivities were modeled hypothetically and calibrated empirically.Correlations were based on the stochastic models and field-scale hydraulic parameters were contingent on pore-level parameters.By considering variation in pore-size distributions over eh conduction interval,the relations were scaled-up for use at aquifer-level.Material-level electrical conductivities were determined by using Vertical Electrical Survey and hydraulic conductivities by analyzing aquifer tests of eight boreholes in the Olbanita aquifer located in Kenya rift.VES datasets were inverted by using the computer code IP2Win.The main result is that ln T=0.537(ln Fa)+3.695;the positive gradient indicating eh conduction through pore-surface networks and a proxy of weathered and clayey materials.An inverse(1/F-K)correlation is observed.Hydraulic parameters determined using such approaches may possibly contribute significantly towards sustainable yield management and planning of groundwater resources.展开更多
文摘The study aimed to develop a customized Data Governance Maturity Model (DGMM) for the Ministry of Defence (MoD) in Kenya to address data governance challenges in military settings. Current frameworks lack specific requirements for the defence industry. The model uses Key Performance Indicators (KPIs) to enhance data governance procedures. Design Science Research guided the study, using qualitative and quantitative methods to gather data from MoD personnel. Major deficiencies were found in data integration, quality control, and adherence to data security regulations. The DGMM helps the MOD improve personnel, procedures, technology, and organizational elements related to data management. The model was tested against ISO/IEC 38500 and recommended for use in other government sectors with similar data governance issues. The DGMM has the potential to enhance data management efficiency, security, and compliance in the MOD and guide further research in military data governance.
文摘On a sunny afternoon,Nelly Wahome mounted a smartphone on a tripod to film one of Mombasa’s tourist hotspots-Nyali Resort,a popular northern beach resort in Kenya.Wahome,25,shared the latest video clip via her TikTok handle in a quest to enchant her followers with the day’s tourism scene along Nyali’s coastline.Within a few hours of uploading,her content attracted hundreds of views.
文摘Kenya is set to become the first country in Africa to start exporting avocados to China, once a recent agreement signed between the two countries comes into effect. The deal is expected to lead to the export of 40 percent of the country's avocado produce to China, according to the Kenya Plant Health Inspectorate Service (KEPHIS), and also opens the door for the export of other horticultural crops such as flowers, French beans, baby corn, broccoli and sugar snaps.
基金supported by the Sino-Africa Joint Research Centre,Chinese Academy of Sciences(SAJC201612)
文摘The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted on Afromontane ecosystems have compared the altitudinal patterns of small mammal diversity. We investigated the species diversity and abundance of non-volant small mammals(hereafter ‘small mammals')on Mt. Kenya, the second tallest mountain in Africa,using a standard sampling scheme. Nine sampling transects were established at intervals of 200 m on the eastern(Chogoria) and western(Sirimon) slopes.A total of 1 905 individuals representing 25 species of small mammals were trapped after 12 240 trap-nights.Abundance was highest at mid-elevations on both slopes.However, species richness and their distribution patterns differed between the two slopes. More species were recorded on Chogoria(24) than on Sirimon(17). On Chogoria, species richness was higher at mid-high elevations, with a peak at mid-elevation(2 800 m a.s.l.),whereas species richness showed little variation on the Sirimon slope. These results indicate that patterns of species diversity can differ between slopes on the same mountain. In addition, we extensively reviewed literature on Mt. Kenya's mammals and compiled a comprehensive checklist of 76 mammalian species. However, additional research is required to improve our understanding of smal mammal diversity in mountain habitats in Africa.
基金funded by the United States Fish and Wildlife Service and Cleveland MetroPark Zoo
文摘The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by the Massai people in the east side of Amboseli National Park in Kenya. The data were collected from grasslands designated into four types： （1） grassland from previous Massai settlements that had been abandoned for over twenty years; （2） grassland excluded from livestock grazing for eight years; （3） a dry season grazing area; and （4） a continuous grazing area where grazing occurred throughout all seasons. Collected data included grass species composition, grass height, inter-tuft distance, standing grass biomass and soil characteristics. The results indicated that continuous grazing area in semiarid rangelands exhibited loss of vegetation with negative, long-term effects on grass functional qualities and forage production, whereas grassland that used traditional Maasai grazing methods showed efficiency and desirable effects on the rangelands. The results also showed that abandoned homestead sites, though degraded, were important nutrient reservoirs.
基金the financial support provided by the Flemish Interuniversity Council (VLIR) of Belgium in favour of the first author
文摘Rangeland degradation is a serious problem throughout sub-Saharan Africa and its restoration is a challenge for the management of arid and semi-arid areas. In Lake Baringo Basin of Kenya, communities and individual farmers are restoring indigenous vegetation inside enclosures in an effort to combat severe land degradation and address their livelihood problems. This study evaluated the impact of enclosure management on soil properties and microbial biomass, being key indicators of soil ecosystem health. Six reseeded communal enclosures using soil embankments as water-harvesting structures and strictly regulated access were selected, varying in age from 13 to 23 years. In six private enclosures, ranging from 3 to 17 years in age, individual farmers emulated the communal enclosure strategy and restored areas for their exclusive use. Significant decreases in bulk density, and increases in the soil organic carbon, total nitrogen and microbial biomass contents and stocks were found in the enclosures as compared with the degraded open rangeland. In the private enclosures, the impact of rehabilitation on the soil quality was variable, and soil quality was in general lower than that obtained under communal management. The significant increase of absolute stocks of carbon, nitrogen and microbial biomass compared to the degraded open rangeland indicates the potential for the restoration of soil quality through range rehabilitation. Over-sowing with indigenous legume fodder species could improve total nitrogen content in the soil and nutritional value of the pastures as well.
基金supported by the National Science Foundation of China(No.41920104010,41877250,and 41807243)。
文摘The Kenya Rift Valley is relatively prone to underground erosion ground fissures and associated disasters,which gravely hinder local engineering construction and economic development.In this research,we performed field and experimental studies on ground fissures in the Kenya Rift Valley area,and determined the structural characteristics of underground erosion fissures.Based on a geological survey of the area,we generalized a geological model for typical ground fissures and reproduced the intermediate process of ground fissure propagation using a large-scale physical model test.Further,the development process of underground erosion fissures were categorized into four stages:uniform infiltration,preferential infiltration,cavity expansion,and collapse formation stages.During the development of underground erosion fissures,water content was distributed symmetrically along the fissures,and these fissures acted as the primary infiltration paths of water.When the ground collapsed,the increase in negative pore water pressure was greater,whereas the increase in positive pore water pressure was less in the shallow soil;moreover,in the deep soil,the increase in positive pore water pressure was greater than that of negative pore water pressure.Additionally,the earth pressure increment initially increased and then decreased with the development of erosion.During underground erosion collapse,the water content and pore water pressure appeared to increase and decrease rapidly.These results can be employed to predict the occurrence of underground erosion ground fissures and the resulting soil collapse.
基金the Sino-Africa Joint Research Center,Chinese Academy of Sciences(SAJC201605 and 151542KYSB20200010)the National Science and Technology Major Project(2018ZX10101004-001-002)Kenya Wildlife Service and National Museums of Kenya。
文摘Emergence and re-emergence of infectious diseases of wildlife origin have led pre-emptive pathogen surveillances in animals to be a public health priority.Rodents and shrews are among the most numerically abundant vertebrate taxa and are known as natural hosts of important zoonotic viruses.Many surveillance programs focused more on RNA viruses.In comparison,much less is known about DNA viruses harbored by these small mammals.To fill this knowledge gap,tissue specimens of 232 animals including 226 rodents,five shrews and one hedgehog were collected from 5 counties in Kenya and tested for the presence of DNA viruses belonging to 7 viral families by PCR.Diverse DNA sequences of adenoviruses,adeno-associated viruses,herpesviruses and polyomaviruses were detected.Phylogenetic analyses revealed that most of these viruses showed distinction from previously described viruses and formed new clusters.Furthermore,this is the first report of the discovery and full-length genome characterization of a polyomavirus in Lemniscomys species.This novel polyomavirus,named Ls Py V KY187,has less than 60%amino acid sequence identity to the most related Glis glis polyomavirus 1 and Sciurus carolinensis polyomavirus 1 in both large and small T-antigen proteins and thus can be putatively allocated to a novel species within Betapolyomavirus.Our findings help us better understand the genetic diversity of DNA viruses in rodent and shrew populations in Kenya and provide new insights into the evolution of those DNA viruses in their small mammal reservoirs.It demonstrates the necessity of ongoing pathogen discovery studies targeting rodent-borne viruses in East Africa.
基金supported by the Sino-Africa Joint Research Centre,Chinese Academy of Sciences(SAJC201612)
文摘Kenya has a rich mammalian fauna. We reviewed recently published books and papers including the six volumes of Mammals of Africa to develop an up-to-date annotated checklist of all mammals recorded from Kenya. A total of 390 species have been identified in the country, including 106 species of rodents,104 species of bats, 63 species of even-toed ungulates(including whales and dolphins), 36 species of insectivores and carnivores, 19 species of primates,five species of elephant shrews, four species of hyraxes and odd-toed ungulates, three species of afrosoricids, pangolins, and hares, and one species of aardvark, elephant, sirenian and hedgehog. The number of species in this checklist is expected to increase with additional surveys and as the taxonomic status of small mammals(e.g., bats, shrews and rodents) becomes better understood.
文摘The aim of this study was to identify Aspergillus species isolated from maize kernels and soils of maize fields of Nandi County using macro and micro morphological characteristics. A cross sectional research design was used in the study and purposive sampling was employed to determine districts of Nandi County and sub locations where sampling was done. This study was part of a larger project whose aim was to survey aflatoxin exposure in the maize value chain. Aspergillus species were isolated from maize and soil samples using quarter strength potato dextrose agar and modified Rose Bengal agar respectively. Pure cultures of the isolates were sub cultured and transferred onto differential media;malt extract agar, czapek yeast extract agar and czapek dox agar for species identification using macro morphological characteristics. Fungal slides were prepared from pure cultures on potato dextrose agar media after three days to identify micro morphological characteristics. Based on morphological characteristics, seven sections of Aspergillus namely: Flavi, Fumigati, Nigri, Circumdati, Clavati, Nidulantes and Candidi were identified. Aspergillus section Flavi was the most predominant with 57% followed by section Nigri with 27% from maize and 58% of section Flavi followed by 26% of section Nigri from the soil across the three locations. Aspergillus sections Nidulantes and Candidi were rare and only recovered from the soil samples of Kaptumo location. All the Aspergillius flavus that formed sclerotia both from the soils or maize kernels were of the L strains. In conclusion Aspergillus section Flavi was most frequent during the isolation process and dominated with Aspergillus flavus from both the maize and soil. Morphological characteristics remain the primary tool for detection and identification of Aspergillus species. The significance for high incidence of Aspergillus section Flavi is in regard to their aflatoxin production profiles that poses a health threat to the community and it is of public health concern. Morphological characteristics as a primary tool for Aspergillus identification should be embraced and more personnel with the knowledge are required since modern and faster techniques are scarce and expensive.
基金supported by the Sino-Africa Joint Research Centre,Chinese Academy of Sciences(SAJC201612)
文摘Ecological dynamics and faunal diversity documentation is normally conducted by direct observation and trapping of live animals. However,surveys of carnivore scat prey and surface bone remains, which are relatively inexpensive, can provide complementary data that expand carnivore diet breadth and may improve accuracy regarding inferences of the ecological dynamics of a given ecosystem. We used this inexpensive method to document species diversity variation with elevation on the leeward(Sirimon) and windward(Chogoria)areas of Mt. Kenya. Bone and fecal specimens were opportunistically collected by walking 2 km in opposite directions from transect points selected at 200-m intervals along the elevational gradient of the study areas. We collected a total of 220 carnivore fecal and owl pellet specimens from both study sites, which were mainly deposited by the spotted hyena(Crocuta crocuta), leopard(Panthera pardus),serval(Leptailurus serval), genet(Genetta sp.), and Mackinder's Cape owl(Bubo capensis mackinderi).Serval scats were the most common, followed by those of the spotted hyena. Scats and bones were found at the lowest density at the lowest elevations,peaked at mid-higher elevations, and then declined at the highest elevations. Based on skeletal analysis only, there were more species in Sirimon(19) than in Chogoria(12). Small fauna(rodents to duiker size bovids) formed the bulk of the identified remains,representing 87.9% of the Sirimon fauna and 90.9% of the Chogoria fauna. The genus Otomys was the dominant prey of the owl and serval in both sites. Three giraffe teeth were found at 3 500 m a.s.l. in Chogoria on the edge of Lake El is, suggesting that it is an occasional visitor to such high elevations. This study underscores the value of fecal and bone surveys in understanding the diet and diversity of mammals in ecological ecosystems,but such surveys should be complemented with analysis of hairs found in scats to obtain a more complete list of carnivore prey at Mt. Kenya.
文摘Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significant source of protein, carbohydrates, and minerals especially for poor populations in the Kenya, it is said to be poor man’s meat. The aim of this study was to determine nutritional composition of newly bred ten cowpea lines and five varieties commonly grown in Eastern Kenya of Kitui, Machakos and Makueni counties to understand their potential utilization in curbing rising food and nutrition insecurity in arid and semi-arid lands ASALs and in any other food applications in Kenya. The experiment was arranged in Completely Randomized Design (CRD) whereby proximate composition and minerals were determined using standard AOAC and AACC methods and technological characteristics checked using modified methods used by other researchers. Collected data were subjected to Analysis of Variance (ANOVA) using SAS (2006) version 9.1, mean separation was done using Tukey’s Honestly Significant Difference (HSD) method at 5% level of significance. Cowpeas composition ranged from 12.28% - 13.35% for moisture content, 49.37% - 55.74% for total carbohydrates, 2.99% - 3.34% for crude ash, 0.13% - 0.81% for crude lipids, 23.37% - 29.70% for crude protein and 1.40% - 4.34% for crude fibers. Cowpea samples recorded highest percentage of essential amino acids (60.71%) and non-essential amino acids (39.29%). Minerals ranged from 1.97 - 2.69 mg/100g for calcium, 3.23 - 3.90 mg/100g for magnesium, 205.53 - 223.30 mg/100g for sodium, 0.80 - 1.23 mg/100g for zinc, 1071.15 - 1152.62 mg/100g for potassium and 0.62 - 1.06 mg/100g for phosphorus. For technological properties, lines absorbed water equivalent to their weights and they were comparable to varieties grown in the region. From the results it showed that cowpea line IT97K-1042-3, TEXAN PINKIYE, TX123, IT85F-867-5, IT82D-889-1 and IT82D-889 have desirable attributes such as high crude protein contents, good water absorption capacities and volumetric expansion. They compared well with existing K80 variety. These cowpea lines could possibly be bred and combined into a single cowpea line and further improved by breeders to have other good properties such as higher levels of water absorption during soaking hence reduced cooking times. Therefore, this work has shown that cowpea lines developed can be used as food security crop, industrial food applications and enriching foods of low protein like in complementary foods for healthy food supply in Eastern Kenya.
基金funded by Sino-Africa Joint Research Center (SAJC201313 and SAJC201605)External Cooperation Program of CAS (153211KYSB20160001)National Science and Technology Major Project (2018ZX0101004)
文摘We describe the first genome isolation of Middle East respiratory syndrome coronavirus(MERS-CoV) in Kenya. This fatal zoonotic pathogen was first described in the Kingdom of Saudi Arabia in 2012. Epidemiological and molecular evidence revealed zoonotic transmission from camels to humans and between humans. Currently, MERS-CoV is classified by the WHO as having high pandemic potential requiring greater surveillance. Previous studies of MERS-CoV in Kenya mainly focused on site-specific and archived camel and human serum samples for antibodies. We conducted active nationwide cross-sectional surveillance of camels and humans in Kenya, targeting both nasal swabs and plasma samples from 1,163 camels and 486 humans collected from January 2016 to June 2018. A total of 792 camel plasma samples were positive by ELISA. Seroprevalence increased with age, and the highest prevalence was observed in adult camels(82.37%, 95%confidence interval(CI) 79.50–84.91). More female camels were significantly seropositive(74.28%, 95% CI 71.14–77.19)than male camels(P \ 0.001)(53.74%, 95% CI 48.48–58.90). Only 11 camel nasal swabs were positive for MERS-CoV by reverse transcription-quantitative PCR. Phylogenetic analysis of whole genome sequences showed that Kenyan MERSCoV clustered within sub-clade C2, which is associated with the African clade, but did not contain signature deletions of orf4 b in African viruses. None of the human plasma screened contained neutralizing antibodies against MERS-CoV. This study confirms the geographically widespread occurrence of MERS-CoV in Kenyan camels. Further one-health surveillance approaches in camels, wildlife, and human populations are needed.
文摘Bacterial wilt (BW) caused by Ralstonia solanacearum is one of the most damaging diseases of potato (Solanum tuberosum L.) in Kenya and worldwide. In Kenya, potato tuber yield losses due to BW infection are estimated at 50 ~ 100%. Low soil fertility is also one of the most important constraints limiting potato production in central Kenya highlands. Farmers tackle this problem through use of inorganic fertilisers and organic manures, both of which amend the soil environment to influence bacterial wilt development. Undecomposed organic manures can also introduce the pathogen into a clean field. Between short rains 1999 and 2000, 10 on-farm extension-researcher- farmer-designed and farmer-managed trials were done at Kianjuki catchment in Embu District. The objective was to use farmers?participatory research approach and select the most suitable organic and inorganic fertiliser combination(s) with lowest BWI and acceptable usable tuber yields, and also to demonstrate use of some components of integrated disease management methods in reduction of disease incidence and spread. Seven treatments were proposed, presented to the farmers for discussion and the most relevant four were selected for evaluation. A newly released potato variety 慉sante?was planted during the short rains 1999 and long rains 2000. BWI didn抰 result in significant differences between treatments but the tuber yields were significantly different in short rains of 1999 and 2000. During short rains 2000, both BWI and tuber yields and unusable tubers differed significantly between treatments. The results confirmed that well- decomposed manures or manures from pathogen-free areas can be used in combination with inorganic fertilisers to improve soil fertility and potato tuber yields in smallholder farms without influencing BWI. Use of certified seed tubers in pathogen free field and following recommended field sanitation measures resulted in apparently bacterial wilt free crop. Considering the high cost of inorganic fertiliser and its negative effects on the environment, reduced usage at half the recommended rates combined with half rates of FYM is feasible option friendly to the farmer, soil and environment. The interviewed farmers also ranked the option as the most appropriate combination for soil fertility improvement for potato production in smallholder farms.
文摘Noise is any sound that causes physiological uneasiness to the ear. People in many environments today, especially urban ones, are exposed to such noise without realizing its potential danger to their healthy hearing. This situation is largely contributed to by the little attention that most governments, especially in the developing countries, pay to noise as a pollution issue. This paper describes a study that aimed at measuring the noise levels at selected points in Nairobi’s CBD with a view to generate a noise map over the study area in addition to identifying areas of high noise intensity or noise hot spots. The study found that noise levels, on average, varied from 61 db to 78 db, increasing from the west to the east of the CBD, and emanated mainly from vehicular traffic;several noise hotspots were also identified, and they are located mainly to the east of the CBD. The paper concludes that although the study was not city-wide, the noise levels observed are high enough to warrant further research and action by the environmental authorities.
基金The study was partially financed by AGH-UST 16.16.140.315/10.
文摘Groundwater samples were evaluated throughout Turkana County(Kenya,East Africa)while looking for drinking water sources.Some samples showed high concentrations of fluoride with values in the range of 0.15–5.87 mg/L.Almost 50%of the samples exceeded the WHO and Kenyan potable water standard guideline value of 1.5 mg/L for drinking water quality.The hydrogeochemical studies revealed that the dominant cation in water is Na^(+)and the dominant anion is HCO_(3)^(-)resulting in Na-HCO_(3) type of groundwater,followed by Ca/Mg-HCO_(3) or Na-SO_(4) and Na-Cl in a few cases.Speciation modelling revealed that the groundwater is undersaturated with respect to gypsum and anhydrite,mostly undersaturated with respect to fluorite(6 samples are at equilibrium),and supersaturated or at equilibrium with respect to calcite(CaCO_(3)).Precipitation of calcite favours the dissolution of F-rich minerals in the alkaline medium.Simultaneously,groundwater is enriched with sodium and bicarbonate,probably as a result of chemical weathering of Na-feldspar.Investigated groundwater can be presumably used for drinking purposes from 17 wells,but a detailed investigation of other trace element concentrations is necessary.
文摘Dietary quality is vital in maintaining sound nutritional status. The ecological conditions thus influence the type of diets and their nutritional quality. The purpose of this study was to determine the trace element/mineral content of some of the commonly consumed diets in Machakos, Kitui, Makueni and Mwingi districts. Decorticated maize, beans and finger millet flour samples were purchased from the local markets. For each category, a total of ten samples were collected from each district. The samples were put in plastic bags, sealed and transported to the laboratory in the Institute of Nuclear Science & Technology, University of Nairobi for preparation and analysis. The cooking of the samples was carried out according to local traditional methods. In the decorticated samples, mean copper concentrations were observed to be below 20 μg·g-1;mean zinc concentrations ranged from 34 to 63 μg·g-1 and mean manganese concentrations were in a similar range of 34 to 78 μg·g-1. The mean iron concentrations were significantly high with a range of 161 μg·g-1 to 287 μg·g-1. A similar trend was observed in the beans where the mean copper concentrations varied from 11 to 33 μg·g-1, mean zinc concentrations ranged from a low value of 24 μg·g-1 to a high value of 35 μg·g-1, mean manganese concentrations varied from 33 μg·g-1 to 98 μg·g-1 and the mean iron concentrations ranged from 227 μg·g-1 to 647 μg·g-1. The cooked Muthokoi samples from Machakos district had relatively high mean trace element concentrations: manganese—109 μg·g-1;iron—280 μg·g-1;copper—19 μg·g-1;and zinc—41 μg·g-1. The only exception was mean iron concentrations which were extremely high in samples from Mwingi District where the concentrations varied from 73 μg·g-1 to 1597 μg·g-1. In finger millet flour, the mean manganese concentrations varied from 95 to 290 μg·g-1, whereas the mean iron concentrations ranged from 127 μg·g-1 to 259 μg·g-1. In contrast, the mean copper and zinc concentrations were low in comparison to the manganese and iron concentrations. As a whole, the mean copper concentrations in the diets are significantly low compared to the other three trace elements. However, the total content is not necessarily a reflection of the amount assimilated in the body. Finger millet was found to be an excellent source of manganese and iron whereas beans were observed to be good sources of iron. All the food crops were observed to poor sources of copper.
基金Supported by Major Science and Technology Project in Yunnan Province(2018ZG009).
文摘With 16 Yunnan tea tree varieties and 5 Kenya tea tree varieties as test materials,the differences in biochemical components between Yunnan and Kenya tea tree varieties were compared and analyzed.The results showed that the coefficients of variation of tea polyphenols,amino acids,caffeine,water extract,gallic acid(GA),catechin(C),epicatechin(EC),epicatechin gallate(ECG),epigallocatechin(EGC),epigallocatechin gallate(EGCG)and total catechins in Yunnan tea tree varieties were greater than those in Kenyan tea trees.The contents of tea polyphenols,amino acids,caffeine,water extract,C,EC,EGC,EGCG and total catechins in Yunnan tea tree varieties had no significant differences from those in Kenyan tea trees varieties(P>0.05),while there were significant differences in the contents of GA and ECG between Yunnan tea tree varieties and Kenya tea tree varieties(P<0.05).Therefore,it could be predicted that GA and ECG might be one of the main characteristics of the differences in biochemical components between Yunnan tea tree varieties and Kenyan tea tree varieties.The cluster analysis results showed that when the genetic distance was 15,the 21 tested tea varieties could be divided into three groups with obvious biochemical differences.
基金funded by the Kenya Government through the National Research Fund
文摘Groundwater yield in the Kenya Rift is highly unsustainable owing to geological variability.In this study,field hydraulic characterization was performed by using geoelectric approaches.The relations between electrical-hydraulic(eh)conductivities were modeled hypothetically and calibrated empirically.Correlations were based on the stochastic models and field-scale hydraulic parameters were contingent on pore-level parameters.By considering variation in pore-size distributions over eh conduction interval,the relations were scaled-up for use at aquifer-level.Material-level electrical conductivities were determined by using Vertical Electrical Survey and hydraulic conductivities by analyzing aquifer tests of eight boreholes in the Olbanita aquifer located in Kenya rift.VES datasets were inverted by using the computer code IP2Win.The main result is that ln T=0.537(ln Fa)+3.695;the positive gradient indicating eh conduction through pore-surface networks and a proxy of weathered and clayey materials.An inverse(1/F-K)correlation is observed.Hydraulic parameters determined using such approaches may possibly contribute significantly towards sustainable yield management and planning of groundwater resources.
