Natural Resources Management

Permanent URI for this collection

https://repository.nrf.go.ke/handle/123456789/27

Browse

Now showing 1 - 20 of 79

A botanical inventory and diversity assessment of Mt. Marsabit forest, a sub-humid montane forest on the arid lands of northern Kenya
(Wiley, 2007) Githae, E. W.; Chuah-Petiot, M.; Mworia, J. K.; Odee, D. W.
A botanical inventory and diversity of trees, shrubs (≥5 cm diameter at breast height [dbh]), herbs,climbers and lianas was assessed in plots (154) of 20 × 5 m in Mt. Marsabit forest, northern Kenya. Werecorded 52 species of trees and shrubs, twelve species of herbs and six species of climbers and lianas.They belonged to 35 families and 64 genera. Rubiaceae was the richest family with nine species followedby Euphorbiaceae (six), Oleaceae (five), Rutaceae (four), Capparaceae, Labiatae and Leguminosae (threeeach). The rest of the families were represented by one or two species. Rinorea convallarioides (Bak.f.)Eyles ssp. marsabitensis Grey-Wilson (Violaceae), an endemic species, and Drypetes gerrardii Hutch.(Euphorbiaceae), were the two most important species, accounting for more than third of the combinedimportance value. Species diversity indices were 2.735 (Shannon–Wiener), 0.88 (Simpson's) and 0.296(Evenness). There was a strong evidence of disturbance arising from anthropogenic and wildlife foragingactivities. This inventory has affirmed Mt. Marsabit forest as a unique habitat for several endemic, rare,threatened or vulnerable plant species, which should be conserved.
A Review of Toxic Metals and Hazardous Organics in Wood Treatment Sites and Their Etiological Implications
(Journal of Chemical Reviews, 2022-02-07) Miranji, Edwin K.; Kipkemboi, Pius K.; Kibet, Joshua K.
Increased natural and human activities over the last century have led to excess levels of inorganic and organic pollutants into the environment and natural ecosystems. This review critically examines heavy metal and organic pollutants' role in wood treatment sites and their etiological consequences. These pollutants are not only recalcitrant but also tenacious to degradation under ordinary conditions. Although some heavy metals are essential to human health, they are toxic at elevated concentrations. Heavy metals feature carcinogenic properties and cause serious health risks to live systems and the environment because of their bio-accumulative, non-degenerative, and refractory characteristics. On the other hand, organic pollutants are readily introduced into the ecosystem from irresponsible use of detergents, volatile organic compounds, paints, pesticides, and wood preservatives. During the wood treatment process, various chemicals are used to enhance durability. Nevertheless, the use of wood preservatives such as chromated copper arsenate (CCA) and pentachlorophenol (PCP) potentially induces pollutants considered detrimental to human health and the ecological environment. Remediation of wood treatment sites using phytomanagement strategies and nanotechnologies has been presented in this review. Therefore, some challenges and recommendations for further research and applications are herein presented.
Africa Inland Church (AIC) Arguments On Cattle Rustling Wars and Insecurity among The Pokot and Tugen of Kenya
(RSIS International, 2019) Daniel Rotich Kandagor; Charles C Moindi
In Clemens Greiner’s article on “Guns, land andvoters: Cattle rustling and the politics of boundary(re)makingin Northern Kenya”, it is evident that competition for naturalresources in Baringo Plains (Anderson, 2002) is one of themain factors for the protracted conflicts between the Tugenand Pokot communities (Greiner, 2013). Consequently, EmmaElfversson in her conference paper underscores the role ofreligion in conflicts by saying, “The importance of religionand prayers in building support for, and sustaining, peaceshould not be underestimated… ( Elfversson,September,2014.p23).The role of Religion, therefore, in resolving conflictsin society can be discussed both positively and negativelyrespectively. This is true because religion is often depicted asa trigger factor in many conflicts due to the fact that peoplerelate to it as part of their identities (Kellas, 1998:33).Accordingly, in some parts of the world, people from differentreligions live in peace and coexist without any conflict.Therefore, the relationship between religion and conflict is acomplex one, and scholars need to take into considerationmany factors before one can argue that religion is the maincause of conflict and vice verse (Goldstein, 1994:159).
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.
An Examination of the Nature of Sand Harvesting Conflicts and their Influence on Poverty Alleviation Initiatives in Makueni County, Kenya
(IISTE, 2015) Muthomi, Simon; Okoth, Pontian; Were, Edmond; Vundi, Silvia
Though natural resources play an important role in the economies of many countries, conflicts associated with their access continue to contribute to poverty in many African countries. While studies confirm conflict-poverty nexus for high value natural resources, scanty information is available on the low value resources. This study, therefore, examined one such low value resource – sand. The objective was to examine the nature of sand harvesting conflicts and their influence on poverty alleviation initiatives in Makueni County. The study employed descriptive and historical designs. The study was guided by the Resource Curse and Poverty Theories. The study sample comprised of 420 sand harvesters and several key informants. Data collection was done using questionnaires, interviews, focus group discussions and observation. Presentation of data was done using both quantitative and qualitative approaches. The study findings established that sand harvesting in Makueni County has been linked to violent conflicts which left many people either maimed, killed or without their property. These had increased poverty levels in the County. The study therefore recommends for establishment of appropriate institutions to mitigate on the conflicts in order to ensure that sand harvesting provides contributes to poverty alleviation in Makueni County.
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.
Assesment Of The Concentration Of Selected Heavy Metals (Pb, Cu, Cd, Zn) In Soils Within The Nyambera Dumpsite
(Research Gate, 2020-06-26) Okemwa, Evans; Obed, Nyabaro; Kituyi, John; Mukenyi, Peter
Heavy metals are part of the soil, but at high concentration levels are considered toxic. With the current exponential population growth, urbanization, industrialization and advancement in agriculture has increased solid waste significantly over time. Due to lack of proper well-structured waste management systems, solid waste has been disposed in open dumpsite which lack any mechanism of control. Over time, due to accumulation-various heavy metals are introduced in the soils and end up being leached, carried away by surface-runoff or introduced to plants by farmers who rely on refuse (from the dumpsite) to plant their crops. This study was aimed at determining the concentration levels of Pb, Cu, Cd and Zn at the Nyambera dumpsite and compare their levels with the WHO recommendation levels for soils. Stratified random sampling was employed and soil samples collected on top of the dumpsites, the slope of the dumpsite and at the banks of river Nyakomisaro which flows adjacent to the dumpsite. Digestion was carried using concentrated hydrochloric acid then topped up to 100ml. Metal analysis was carried out using ICPOES. The results of Pb, Cu, Cd and Zn were as follows 91.31, 281.8, 3.253 and 542.3 ppm respectively. The concentrations were found to be very high at the dumpsite as compared to the recommended levels by WHO. Based on the results obtained the dumpsite should be treated with various remediation methods being applied to help lower the levels of these metals. Farmers using the refuse as manure for their crops should seek other alternatives for their farms.
ASSESSMENT OF EFFECTS OF LAND USE PRACTICES ON RIVER CATCHMENTS A CASE STUDY OF NYONGORES RIVER CATCHMENT
(University of Eldoret, 2016) Langat, Wesley Kiprotich
Nyongores River is one of the major tributaries of Mara River and is located at the upper catchment of Mara River Basin. Over the years, rising population pressure and intensification of agriculture in the catchment has led to; reduced vegetation cover, poor land use management practices and increased soil erosion. The river is currently one of the major contributors of sediment and agrochemicals in the Mara River and Lake Victoria. The goal of the study was to assess the effects of land use and management practices on sediment concentrations in rivers. The specific objectives were: to map land use types, determine sediment delivery rates from land use types, determine sediment load from the main tributaries and assess the existing land use management practices for soil conservation. GIS mapping, water sampling and interviews of farmers from the catchment were carried out in the month of December 2009, January, February and March 2010. The study revealed that 43.2% of the catchment land use was under maize, 33.6% grasslands, 16.1% tea cover, 4.9% forest cover and 2.2% bare land. Land use under maize cultivation contributed the highest sediment concentration of 0.26g/l, forest (0.024g/l) and tea cultivation contributed the least concentration of 0.0351g/l. Among the tributaries of Nyongores River, Chepkositonik River delivered the highest sediment of 0.493 g/l followed by Kagawet with 0.324 g/l, then Ainopng'etunyek with 0.255 g/l while Kiprurugit was the least with 0.198g/l. The study estimated sediment flow into Nyongores River from the four tributaries at about 0.559Kg/s. The study established that the land use management practices for soil conservation within the catchment were; contour ploughing (24%), terraces (20%), agroforestry (17%), planting of trees (17%), intercropping (12%), mulching (6%), gabions (3%) and sand bags (1%). The study has demonstrated that there exists relationship between land use and sediment delivery rates in the tributaries. The study also shows that various land use management practices influences the rates of sediment concentrations in the rivers. Hence, recommends the adoption of integrated river catchment management for sustainable environment and agriculture.
Assessment of land use/land covers changes linked to oil and gas exploration: Developments under changing climatic conditions in Lokichar Basin, Turkana County
(2020) Kariuki, David Mugendi; Mireri, Caleb; Kibwage, Jacob; Oyoo, Daniel
Understanding land use/land cover changes(LU/LC) linked to oil and gas exploration under changing climatic conditions in South Lokichar Basin is crucial.This knowledge will inform policy makers on appropriate sustainable vegetation cover management strategies for the sake of pastrolism practiced in the area.The LU/LC changes were assessed using multi-spatial and multi-temporal remotely sensed imageries acquired through Landsat 5TM and Landsat 8OLI/TIRS by use of ArcGIS.The study assessed medium resolution spatial imageries acquired for the area in both rainy and dry seasons,before oil and gas exploration developments begun in South Lokichar Basin between 2006-2011 and after commencement between 2012-2017.The study established that the average area in hectares under vegetation cover had declined since oil and gas exploration developments begun.A one sample t-test statistics indicated that the area under forest,shrubland and grassland cover had significantly reduced at 90% confidence interval with a p-value of 0.072,0.074 and 0.061 respectively.The study established a decline in NDVI from 1 to 0.433 for the rainy season and 0.411 to 0.122 for the dry season between 2006 and 2017 with a p-value of 0.009 <0.05 on paired t-test implying a significant change on vegetation cover.Sustainable management of vegetation cover is important to safeguard livestock forage.
Assessment of levels of natural radioactivity in surface soils around titanium mines in Kenya
(Kenyatta University, 2011) Masore, Kefa Osoro
All human beings are exposed to radiation from naturally occurring radionuclides in soil and other environmental materials. Some of these exposures are not amenable to control and they are usually referred to as background radiation. Some work activities such as conventional mining inadvertently produce large quantities of naturally occurring radionuclides, which can result in additional and/or elevated levels of radiation exposure of people in the areas around the mining sites. Such exposures - induced or enhanced by human activities - are subject to control by regulatory authorities. In some instances there may be contributions from the two types of exposures and they must be separated before applying regulatory control. In this study, natural radioactivity levels in surface soils around the proposed titanium mines in Kwale district were determined from measurements of 78 samples of surface soils randomly sampled from two villages within the proposed mining area by using a hyper pure germanium (HpGe) gamma-ray spectrometer. The values of radioactivity concentrations in the soils and the likely radiation doses from contact with these soils were determined and are reported in this thesis. The radiological implication of these levels is discussed with regards to the impending mining operations in the area. The ranges and mean of radioactivity concentrations (Bgkg-l) obtained are. 8.4±0.4-43.6±1.5 (_27.6±1.7) for 232Th; 7.4±0.6-40.6±1.4 .(20.9±1.5) for 226Ra and 31.9±1.3-114.1±1.4 (69.5±3.2) for 40K, respectively. The likely absorbed dose rates in air above these soils were calculated from these radioactivity concentrations and found to be 8.5±0.5-36.9±1.1 nGyh-1 with a mean of 25.2±1.4 nGyh-1. The corresponding effective dose rates are 21.0±1.2-90.8±2.6 mSvy--1 with a mean of 62.0±3.5 uSvy--1, which are lower than the global average of 0.46 mSvy 1 and therefore of little radiological risk to the environment of the study subject.
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.
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.
Biological control of desert locust (Schistocerca gregaria Forskål)
(CABI Reviews, 2021-03-06) Githae, Eunice W.; Kuria, Erick K.
Desert locust (Schistocerca gregaria Forskål) is one of the most serious agricultural pests in the world due to its voracity, speed of reproduction, and range of flight. We discuss the current state of knowledge on its biological control using microorganisms and botanical extracts. Metarhizium flavoviride was among the first fungus to be recognized as a bio-control agent against desert locust in the laboratory and field conditions. Nevertheless, its oil formulation adversely affected non-target organisms, hence led to further research on other microorganisms. Metarhizium anisopliae var. acridum (syn. Metarhizium acridum) is an environmentally safer bio-pesticide that has no measurable impact on non-target organisms. However, there are various shortcomings associated with its use in desert locust control as highlighted in this review. Bacterial pathogens studied were from species of Bacillus, Pseudomonas, and Serratia. Botanical extracts of 27 plant species were tested against the locust but showed varied results. Azadirachta indica and Melia volkensii were the most studied plant species, both belonging to family Meliaceae, which is known to have biologically active limonoids. Out of the 20 plant families identified, Apiaceae was the most represented with a frequency of 21%. However, only crude botanical extracts were used and therefore, the active ingredients against desert locust were not identified. Through a comprehensive research, an integrated pest management strategy that incorporates these bio-controls would be a realistic option to control desert locust infestations.
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.
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.
Climate variability, land-use, pastoral and agropastoral livelihoods in arid and semi-arid areas of Kenya
(World Journal of Innovative Research, 2021-05-05) Amwata, Dorothy A.; Nyariki, Dickson M.
Kenya's arid and semi-arid lands (ASALs) are experiencing climate variability, especially rainfall and temperature alterations. Rainfall is recognised as one of the critical parameters influencing land-use dynamics and consequently livelihoods in the arid and semi-arid areas inhabited by pastoral and agropastoral communities. Climate variability influences the type of livestock kept, crops grown and diversity of livelihood options. To understand how climate variability and change contribute to land-use changes, questionnaire interviews, Focus Group Discussions and direct observations were used to obtain information from 98 and 100 households in Kajiado and Makueni Counties respectively. In addition, desk reviews were carried out on government reports, previous studies and publications. The data obtained were analysed through descriptive and inferential statistics. The study found out that land-use activities, land sizes, livestock numbers, type of crops grown and adaptation options vary across rainfall gradients and are some of the factors that determine if a household would diversify its farm and non-farm activities. However, there two production systems have shown some similarities in adaptation options such as migration and diversification. Therefore developments in the ASALs need to holistically adopt a systems approach to land management taking into consideration all existing land-use systems in the study area as a pre-requisite for sustainability of ASAL ecosystems.
Combining Sustainable Land Management Technologies to Combat Land Degradation and Improve Rural Livelihoods in Semi-arid Lands in Kenya
(Springer Verlag, 2015-07-16) Mganga, Kevin Z.; Musimba, Nashon K. R.; Nyariki, Dickson M.
Drylands occupy more than 80 % of Kenya’s total land mass and contribute immensely to the national economy and society through agriculture, livestock production, tourism, and wild product harvesting. Dryland ecosystems are areas of high climate variability making them vulnerable to the threats of land degradation. Consequently, agropastoralists inhabiting these ecosystems develop mechanisms and technologies to cope with the impacts of climate variability. This study is aimed to; (1) determine what agropastoralists inhabiting a semi-arid ecosystem in Kenya attribute to be the causes and indicators of land degradation, (2) document sustainable land management (SLM) technologies being undertaken to combat land degradation, and (3) identify the factors that influence the choice of these SLM technologies. Vegetation change from preferred indigenous forage grass species to woody vegetation was cited as the main indicator of land degradation. Land degradation was attributed to recurrent droughts and low amounts of rainfall, overgrazing, and unsustainable harvesting of trees for fuelwood production. However, despite the challenges posed by climate variability and recurrent droughts, the local community is engaging in simple SLM technologies including grass reseeding, rainwater harvesting and soil conservation, and dryland agroforestry as a holistic approach combating land degradation and improving their rural livelihoods. The choice of these SLM technologies was mainly driven by their additional benefits to combating land degradation. In conclusion, promoting such simple SLM technologies can help reverse the land degradation trend, improve agricultural production, food security including access to food, and subsequently improve livelihoods of communities inhabiting dryland ecosystems.
Conflict of Interest in Exploitation and Utilisation of Transboundary Natural Resources on Lake Victoria
(Digital Commons, 2016) Were, Edmond
The management of Lake Victoria as a “regional common” is expected to adhere to the global principles of transboundary natural resource management. However, national interest and power asymmetry amongst riparian states buoyed by external demand have overwhelmed global and regional norms leading to incessant exploitation of the common resources. This paper uses idealist and realist perspectives of power relations to inform the analysis of conflicting interests in transboundary natural resource exploitation. It partly relies on 2012-2013 primary data from purposively selected Beach Management Units in Kenya and Uganda and secondary data from regional fisheries institutions. Notwithstanding the normative value of global conservation principles, demand-driven globalization buttressed by national vested interests and the National Measures clause of the Lake Victoria Fisheries Organization have led to unsustainable exploitation of the shared resources on the lake. Lake Victoria thus epitomizes a clash of global and local interests in the use of shared natural resources.
COPING STRATEGIES AND OPPORTUNITIES FOR CLIMATE-SMART AGRO-PASTORALISM: A CASE STUDY OF NAROK COUNTY IN KENYA
(Chuka University, 2015) Githae, E. W.
Pastoralism is the main form of livelihood in the arid and semi-arid lands of Kenya that host about 10 million people and approximately 70% of the national livestock herd. However, livestock production is threatened by climate related hazards as witnessed by deaths, reduced dairy yields, degraded natural resources and high incidences of pests and diseases. The traditional coping strategies have been affected by persistent climatic variations and socio-economic changes that have led to increased insecurity of livelihoods. The communities have, therefore, developed other strategies to cope with the harsh climatic conditions, and knowledge of these strategies is important in addressing current and future climatic challenges. This study, therefore, assessed the pastoralists of Narok County to determine their perception towards climate change and its impacts, to identify coping strategies and to evaluate the constraints faced towards a sustainable climate-smart livelihood. The study used focus group discussions and key informant interviews from three selected regions and integrated secondary data from various sources. The results indicate that these communities had observed remarkable changes in weather patterns and high prevalence of pests and diseases over the last 10 years. These impacted heavily on productivity and food security, and worsened by current land use changes. In response, pastoralists have transformed towards agro-pastoralism with subsequent shift from communal to private land ownership. They have adopted various coping strategies by diversifying livelihoods to improve food security and reduce vulnerability. However, supporting these strategies faced various challenges, the main ones being unpredictable weather patterns and limited knowledge on soil and water management. The findings provide a framework for sustainable climate-smart agro-pastoralism and policy interventions to enhance long-term sustainable systems that will ensure food security, while simultaneously conserving natural resources.
Copper micronutrient fixation kinetics and interactions with soil constituents in semi-arid alkaline soils
(Taylor & Francis group, 2016-07-07) Udeigwe, Theophilus K.; Eichmann, Madeleine; Eze, Peter N.; Ogendi, George M.; Morris, Molly N.; Riley, Meagan R.
This study examined the fixation pattern and kinetics of plant-available [diethylene triamine pentaacetic acid (DTPA)-extractable] copper (Cu), as well as basic soil properties that influence Cu availability in selected semi-arid soils. Soil samples from six different series were used and data obtained from Cu extraction experiments fitted to various kinetic models. Soils were also characterized for a suite of chemical and physical properties. The majority (80%) of the plant-available Cu fixed over the experimental period of 90 d occurred within the first 14 d. The amount of plant-available Cu fixed within the first 14 d tended to be influenced by the combination of organic matter (OM) and pH. The total amount of Cu fixed at the end of the experimental period of 90 d was influenced by pH and a combination of pH and calcium carbonate. The fixation of plant-available Cu over the experimental period was better described by the power function model [R2 = 0.90, Standard Error (SE) = 0.099] but poorly by the other models (R2: 0.58 to 0.59), while reactions within the first 35 d were better described by the second-order model (R2 = 0.98, SE = 0.008), suggesting a different fixation pattern. Findings from this study provide a basis for a more mechanistic approach to evaluating and comparing the fixation of Cu micronutrient compounds in these semi-arid soils for more scientific management decision making.

Browse

Browsing Natural Resources Management by Title

Results Per Page

Sort Options