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The National Research Fund facilitates research for the advancement of Science, Technology and Innovation. One of our core functions is to compile and maintain a national database of research and innovation projects funded by the Fund and other agencies as per the STI Act of 2013.
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Recent Submissions
Effect of thermal treatment on the pozzolanic activity of natural clay from selected Kenyan wetlands
(Journal of Sustainable Research in Engineering, 2023) Kyungu W. N. Yannick, James W. Kaluli, Benson M. Mwangi, and Hosea M. Mwangi
The use of cement in construction is costly and degrades the environment. Therefore, affordable and easily available
alternatives are needed. This study evaluated the effect of thermal treatment on the pozzolanic activity of clay soils. Three wetland
clays collected from three sub-counties of Murang’a County, Kenya (Kahuro, Kiharu and Maragua Sub-Counties) were studied
after thermal activation. Thermal treatment (calcination) was carried out in an electronic muffle furnace (Advantec KL-420) at
600, 700, and 800°C for a duration of 2 hours. The chemical oxide composition was evaluated using X-ray fluorescence (XRF).
Three methods (electrical conductivity, Frattini test, and compressive strength test method) were used to assess the pozzolanic
activity of clay. A decrease in the electrical conductivity of the lime-clay solution was observed over a 24 hour period. Results of
the Frattini test showed that clay calcined at 600°C and 700°C reacted with Ordinary Portland Cement (OPC) - CEM-I and reduced
CaO and OH- concentrations to levels below the solubility curve of Ca(OH)2. Calcination of clay from Kahuro and Maragua sub
counties, at 600°C and 800°C, respectively, increased the strength activity index of cement blocks from less than 0.75 to about 1
after 28 days of curing. Therefore, a temperature range of 600-800°C was considered effective for calcination. We conclude that
thermal treatment increases the pozzolanic activity of natural clay for use as a replacement for cement. Therefore use of blended
cement may be a sustainable alternative to the use of cement alone.
Seasonal Habitat Shifts and Wetland Dependence of Grey Crowned Crane in Urbanising Kenya
(John Wiley & Sons Ltd., 2025-06-26) Carolyne M. Wachu, Benson M. Mwangi, James Jumbe, Wanyoike Wamiti, Joseph Mwangi
The Grey Crowned Crane (Balearica regulorum) has experienced major global population declines, leading to its uplisting
to Endangered status on the IUCN Red List of Threatened Species. In Kenya, the Nairobi metropolitan area supports one of
the country's substantial remaining populations of this species, yet data on temporal and spatial variation in population and
habitat associations remain limited. This study conducted systematic censuses at 130 sites across five counties between June
2023 and February 2024 to assess patterns in population and habitat use across wet and dry seasons. The observed crane
population was estimated at 1116 individuals, based on the average of wet and dry season counts, with seasonal crude den
sities of 0.127 individuals/km2 in the wet season and 0.14 in the dry season. Adults comprised 93.6% and young individuals
6.4%, with Kiambu County recording the highest proportion of young cranes (44.4%). Crane abundance varied substantially
among counties and was positively associated with the availability of suitable wetland habitats. Habitat use shifted seasonally,
with greater wetland occupancy during the wet season and increased use of grasslands during the dry season. These patterns
highlight the species' strong dependence on wetlands and its flexible foraging behaviour in modified landscapes. Our findings
emphasise the ecological value of even small or degraded wetlands and call for their integration into urban conservation and
land use planning frameworks.
Modeling the Niche Suitability of Grey Crowned Crane (Balearica regulorum) to Inform Conservation Strategies in Kenya
(British Ecological Society and John Wiley & Sons Ltd., 2026-03-26) Carolyne M. Wachu, Benson M. Mwangi, James Jumbe, Wanyoike Wamiti, Denis Kiptoo
The Grey Crowned Crane is listed globally as Endangered, primarily due to threats such as habitat loss, degradation, and frag
mentation, as well as human encroachment, electrocution, and illegal capture. Effective conservation requires knowledge of
the species' current and future spatial distribution under changing climatic conditions. This study addresses these knowledge
gaps by assessing the climate suitability and spatial distribution of the species in Kenya under current and future climate sce
narios. Using occurrence data from the Global Biodiversity Information Facility and climatic variables from WorldClim, species
distribution models were developed to evaluate the species' suitable habitats. The influence of climatic predictors on species
distribution was assessed under two climate change scenarios (SSP2- 4.5 and SSP5- 8.5) for the period 2020–2040. An ensemble
modeling approach combining Generalized Linear Models, Generalized Additive Models, and Random Forest algorithms was
used to predict suitable crane habitats. The distribution map was overlaid with protected area boundaries to assess the coverage
of habitat protection. Results indicate that suitable habitats are largely concentrated in western and southwestern Kenya, with
distribution strongly influenced by temperature and precipitation. The predicted reduction in suitable area, about 49.5% under
SSP2- 4.5 and 47.5% under SSP5- 8.5, highlights the vulnerability of the species to changing climatic conditions. Projections under
the two climate change scenarios revealed a potential contraction in the suitable range, indicating possible adverse impacts of
climate change. These findings provide insights into the climatic drivers of Grey Crowned Crane distribution and offer a basis for
informing conservation planning and habitat management under future climate change
Wetland Degradation Status and Conservation Challenges in Murang’a County, Kenya
(International Journal of Ecosystem, 2021) Benson M. Mwangi
Unregulated human activities have resulted in massive degradation and eventual loss of wetlands despite their
importance in providing various ecosystem services and habitat to important species of fauna and flora. In Murang’a County,
Kenya, wetland degradation has increased at an alarming rate since the 1980s, with no data on their degradation status and
challenges facing their conservation. This study aimed to examine the trend of wetland degradation and the main challenges
impacting their conservation in Murang’a County between 1986 and 2018. The challenges were identified in a stakeholder
workshop involving 39 key stakeholders and ranked in order of importance using the pair-wise ranking technique. Trends in
wetland degradation status were assessed through analysis of land use maps obtained from Landsat images of 1986, 2001, and
2018. The most critical challenges affecting the conservation and management of wetlands in the County were inadequate
legislation followed by poor planning, lack of community empowerment, scarce resources, corruption, encroachment, and
pollution. Correlation analysis between wetland and water areas showed a significant but negative relationship at (P<0.01),
indicating that decreasing wetland areas resulted in a significant reduction of water areas. The wetland area in the County
decreased by about 48% between 2001 and 2018 and to arrest this trend of declining wetland area, the stakeholders
recommended the amalgamation of all laws and policies touching on conservation and management of wetlands in the
County. Further, there is a need for community involvement and empowerment to create awareness of the roles of wetlands
for their well-being.
Threats of Land Use Changes on Wetland and Water Areas of Murang’a County, Kenya
(Published by Science and Education Publishing DOI:10.12691/aees-9-6-2, 2021) Benson M. Mwangi
Globally, wetlands have declined in area by over 50% since 1900, due to changes in land-use patterns,
converting them into farmlands, human settlements, urban centers, and infrastructure development. Land-use
changes also impact negatively on the water area (streams, rivers, lakes, reservoirs, and sea) of an area. In this study,
the threats of land use changes on wetland and water areas in Murang’a County, Kenya, were assessed, in a bid to
understand the main causes for the rapid decline in wetland and water areas in the County. Landsat images of 2001
and 2018 were analyzed using a supervised classification technique to produce Land-use maps in ArcGIS and detect
associated changes. Between 2001 and 2018, the wetland area in Murang’a County declined by over 48% while the
water area declined by over 25%. Bare-soil/built-up area posed the greatest threat to the conservation of wetlands in
the County, taking up 161 ha of the wetland area during the period. The growth of woody shrubs posed the greatest
threat to the loss of water areas taking up 152 ha of the water area during the period. Mean total threats facing
wetlands differed significantly from mean total threats facing water areas in the County (t = 0.682; p<0.001). It is
concluded that wetland and water areas are faced with similar human-induced land use threats but at varying
magnitudes. It is therefore critical that specific regulatory legal and policy structures be urgently instituted to curtail
further wetland and water area losses.
