RP-Department of Environmental Planning and Management

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Evaluating the Spatio-Temporal Distribution of Nitrogen Dioxide, Land Surface Temperature and NDVI in Nairobi City County
(ISPRS-Annals, 2024-11) Mwangi, Patricia
Cities are becoming larger and it is estimated that by the year 2050, more than 6 billion people will be living in cities. As cities expand and grow, the quality of life and conditions will also transform. An integral part of environmental studies has been statistical analysis in modelling the spatial dynamics of land use changes. The research involved the use of satellite imagery to determine yearly averaged values of LST and NDVI from Landsat 8 OLI/TIR and monthly mean values of Nitrogen Dioxide (NO2) from Sentinel 5-Precursor (Sentinel-5P) across Nairobi City County. The datasets covered the period 2019, 2020, 2021, 2022 and 2023 and were analysed in Google Earth Engine. Results indicated that the yearly mean values in NO2 and LST in 2020 reduced by 2% and 12% respectively from 2019, while the mean NDVI value significantly increased by 28% in 2020 from 2019. NO2 has a negative correlation with LST in all years and a positive correlation with NDVI. Pearson correlation with population densities in constituencies in Nairobi in 2019 and 2023 indicate a negative correlation with NDVI and a positive correlation with NO2 and LST. Constituencies that have higher population densities tend to have lower vegetation densities and higher NO2 concentrations and temperature. Vegetation therefore plays a crucial role in air quality and that climatic factors such as precipitation and temperature influence the concentration of pollutants.
Comparative Analysis of Household Residential Preferences Across Neighbourhood Densities in Nairobi, Kenya
(EANSO, 2024-11) Mugah, Faith; Wangai, Peter
Rapid urban growth in Nairobi city outstrips demand and provision of adequate housing. The demand for housing in an area is dependent on the satisfaction of the resident’s needs and wants. This paper examines the residential preferences of residents in three residential estates, low, medium, and high densities in Nairobi City, Kenya. Data was collected by use of questionnaires that were administered to 267 households. Primary data was collected for this study. The data collected was analysed using factor analysis and ordinal regression. Data was presented in the form of tables. The results indicate residential preferences among high, medium and low-density areas vary. The most preferred factors for low-density residents were safety and security, open spaces and facilities; while the residents in high-density areas preferred housing diversity, local employment and close proximity to the workplace. The least preferred factor for low-density residents was close proximity to work place since they own cars hence they are more willing to commute while high-density residents prioritize proximity to work to minimize transportation costs. Residential preferences varied by density, age, gender, education and years lived in an estate. Preference for safer neighbourhoods with open spaces and facilities was high for residents in low-density areas while preference for neighbourhoods with housing diversity, local employment and close proximity to workplaces was high among the residents in high-density estates. These insights under score the importance of addressing the varied needs and preferences of different demographic groups in urban planning and housing policy to create more equitable and livable communities in Nairobi in order to limit housing mismatch. This study contributes to the planning studies by firming up empirical evidence from developing countries that have high populations in urban areas.
Voluntary approaches to water resource management among flower growing firms in Naivasha Sub County, Kenya
(Current Research in Environmental Sustainability, 2022) Amayi, Maureen Kaleha; Majale, Christine
Flower growing firms are key economic players in Kenya contributing to a large portion of the country's Gross Domestic Product. While government regulations have faced accusations of laxity in managing the firms, the former have gradually embraced voluntary measures to aid in enhancing their water resource management goals. This study aimed to uncover the nature of the programs put in place by the firms. A cross sectional survey research design was adopted for the study that was conducted in Naivasha Sub County, an area dominantly known for flower growing firms in the country. Chi square test of independence was done to uncover any sta tistically significant differences between the flower firm types and their perception of the various voluntary approaches towards water resource management. A null outcome was observed whereby the views of the firms were not influenced by their geographical sizes of operation. While all the flower growing firms acknowledged the importance of voluntary efforts to water resource management, some lacked clear structures on imple mentation of the same. The firms were reluctant to share documentation pertaining to their policies although responses obtained indicated that the efforts were still at an infant stage. It has been noted that many flower firms enroll for voluntary programs like certification schemes simply for the purpose of gaining access to markets. The study therefore recommended that the water resource management rules set out in the voluntary approaches need to be made compulsory and monitored by parties outside of the value chain.
Factors Impacting Benefits of Participatory Forest Management in Upper Imenti Forest, Meru County, Kenya
(OJF, 2024-05) Musyoki, Josephine Kamene; Ming’ate, Lamech Felix Mogambi; Muriithi, Joseph; Musingo, Mbuvi Tito Edward; Kagombe, Joram
This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation in forest management through membership of Community Forest Association (CFA) or not. Cross-sectional survey research design was applied for collecting quantitative data using a semi-structured questionnaire administered to 384 households stratified on the basis of PFM participation status. Qualitative data was collected through focused group discussions using a checklist and key informant interviews using an interview schedule. Using Statistical Package for Social Sciences version 25, Binomial regression with Wald Chi-square was analyzed to identify factors perceived to be significantly influencing benefits for PFM participants and Pearson Chi-square to compare factors perceived to be affecting PFM and non-PFM participants. CFA members’ participation in PFM was significantly and positively affected by benefits of PFM income generating activities and forest products accessed in the forest. Benefits linked to Plantation Establishment for Livelihood Improvement System (PELIS) for CFA members were significantly reduced by enforcement of moratorium policy since February 2018, diseases and pests, poor PELIS guideline adherence and animal damage. Benefits related to state forest access for firewood by the CFA members were negatively influenced by the moratorium policy. Diseases and pests affected benefits associated with bee keeping significantly. Comparing factors under different PFM participation status, crop production was significantly affected by policy changes, pest and diseases, animal damage and PELIS guideline adherence for CFA members than for Non-CFA members. Policy changes also affected the CFA members significantly in firewood collection and access to fodder in the state forest than the Non-CFA members. Hence, sustainable community participation in Upper Imenti Forest management requires: increasing PFM benefits, addressing factors reducing benefits and enhancing active participation of CFA members in PFM related decision-making processes.
Impact of Volcanoes National Park Conservation on Local Food Security
(Taylor & Francis Group, 2024-02) Nyiratuza, Madeleine; Maniriho, Aristide; Ming’ate, Felix L. M.; Mireri, Caleb
This study employed mixed methods, including a survey of 400 households, 21key informants, and 10 focus groups conducted in January-March 2019, to evaluate the contribution of Volcanoes National Park (VNP) conservation to local food security in Rwanda. Data was collected from communities within 0-5km and 5-10km park buffers, facilitating distance-based comparisons. Food security status was assessed using the Consolidated Approach to Reporting Indicators of Food Security. Despite government attention to food security, its integration into VNP conservation remains minimal. Shockingly, 71% of local residents experience food insecurity, concentrated within the 0-5km buffer. Interestingly, while only 38% of households directly benefit from park conservation, 72% of these beneficiaries reside within the 0-5km zone. This suggests that community conservation and revenue-sharing programs are disproportionately funded at the park’s edge, where human pressure on resources is most significant. These findings highlight the need for policy and strategy amendments, as well as revisions to the park management plan, to effectively integrate food security concerns into VNP conservation efforts. Linking a specified percentage of revenue-sharing funds to participation in relevant food security programs, co-managing land for conservation and community needs, weaving food aid into safety nets for vulnerable groups, prompt wildlife damage payouts for secured livelihoods and fostered coexistence, and skill training and microloans for diversifying income and curbing poaching are crucial for enhancing food security among households around the VNP.
Effect of Forest Landscape Restoration on Ecosystem Services in Ethiopia: Review for Future Insight
(IJSEI, 2023-12) Hirpa, Giche Yadesa; Letema, Sammy C.; Ming’ate, Felix L.M.
Forests are crucial covering 31% of the Earth’s land surface. Deforestation has caused damage to these forest landscapes limiting their ability to provide ecosystem services like provisioning, supporting, regulating, and cultural services. In response to this degradation issue, the concept of forest landscape restoration was introduced in 2000. This review aims to provide comprehensive studies of existing literature on the effect of forest landscape restoration and restoration time on reversing ecosystem service in Ethiopia. The goal is to inform evidence-based decisionmaking and guide research in this field. The review analyzed 16 studies conducted from 2011 to 2023 that covered aspects of forest landscape restoration. The findings indicated that these restorations had an impact on ecosystem services such as improving soil properties, storing carbon stack, enhancing species diversity, richness, evenness, and regeneration status, and benefiting community livelihood. However, the review found that most of the studies were limited to specific regions, little information on the cultural service, and there were inconsistencies in some research findings. In general, this study provides significant evidence supporting the importance of restoration as a viable strategy to rehabilitate degraded forest landscapes. It also highlights the importance of long-term monitoring and considering ecological conditions for sustainable restoration efforts in regaining ecosystem services.
Sanitation services for the urban poor: A social capital approach to sanitation challenges in informal settlements
(Plos water, 2023-12) Chumo, Ivy; Mberu, Blessing; Wainaina, Cynthia; Murigi, Wanjiru; Sumba, Leunita; Kabaria, Caroline
Poorly managed sanitation is degrading, unhealthy and far too dominant among the urban poor. The conventional solution to poorly managed onsite sanitation and/or open defecation is for governments to provide adequate sanitation at subsidized prices. Few governments in low and middle income countries can subsidize access to sanitation facilities for people living and working in informal settlements. This leaves the urban poor in informal settlements to face challenges in accessing safely managed sanitation, with some residents and manual pit emptiers adopting social capital approaches. We sought to identify sanitation challenges along the value chain and social capital approaches to addressing the challenges. We used qualitative approaches. Our target population were manual pit emptiers and community members. We analysed data using conventional content analysis methodology. We grouped sanitation challenges into those that are outside individual households and those that are at the individual household. Challenges outside the household could not be controlled at the individual level, and included legislative, physical, and social challenges, while challenges at the individual household could be controlled at individual level, and included health, financial and technical challenges. As a result of these challenges, both the manual emptiers and community members adopted social capital approaches, which included the use of reciprocity and trust, networks and information channels and norms to counter the challenges. Sanitation challenges along the sanitation value chain should persuade policymakers and practitioners that sanitation extends beyond the four walls of a sanitation containment facility, to include emptying, transportation, treatment and disposal. Many of the challenges could be attributed to governance outside the sanitation sector. Hence long-term improvement of sanitation conditions in informal settlements ought to be supported by broader policies and strategies like social capital that begins by thinking outside “the sanitation box”.
Possibility of Efficient Utilization of Wood Waste as a Renewable Energy Resource in Ghana
(IFPG, 2023) Takase, Mohammed; Kipkoech, Rogers; Kibet, Joy; Mugah, Faith
Objective: Ghana has an abundance of energy resources, including biomass, hydrocarbons, hydropower, solar, and wind. The purpose of this work is to explain the importance of using, woody biomass in particular as a renewable source of energy. To improve the utilization of all types of woody biomass, particularly those that are currently considered waste, this paper provides an analysis and overview of the possibilities for using wood waste as a renewable energy, as well as the challenges that producers in Ghana face due to underdeveloped markets and a large amount of capital required to begin production of briquettes and pellets. Methods: The research strategy is based on the use of secondary data obtained from the internet, as well as analytic and synthetic methods in the preparation of the paper. As a data source, the literature on the production and use of biomass was used. The "Journal of Renewable Energy Review" and other expert literature were used to determine the energy potential of woody biomass residues in Ghana. Results: More than 3.5 million m3 of wood is cut annually in Ghana to meet the energy demand. Wood biomass has traditionally been used for energy but the way it is used is outdated, and its efficiency is extremely low. Additionally, the current situation on wood biomass, management of waste in saw mills and, the need for future development of the industrial development is also briefly described. It is of great necessity to fulfill what is outlined in the Convention on Climate Change to transition to a more modern method of producing and using woody biomass. Conclusion: Biomass has the potential of replacing 25% of the total energy production. Woody biomass process at sawmills generates more than 20% of residues in form of briquettes and pellets, most of which are not exploited. Creation and utilizations wood waste is limited due to lack of technologies, markets, pollution of environment with primary and secondary waste, etc.
Availability and Accessibility of Toilet Facilities among Low-Income Households in Selected Settlements of Cape Coast Metropolis, Ghana
(IWA Publishing, 2023) Kipkoech, Rogers; Takase, Mohammed; Aliyu, Aminu; Kibet, Joy; Mugah, Faith
Cape Coast Metropolis faces a serious lack of adequate toilet facilities among the low-income households, leading to poor sanitation, health, and environmental degradation. The research explored and provided valuable data on the availability and accessibility of toilet facilities among low-income households. Using a simple random sampling technique,100 closed-ended questionnaires were equally administered to respondents in four Cape Coast Metropolis communities. Descriptive statistics were used to assess the types of toilet facilities available, identify the accessibility of toilet facilities, and ascertain challenges in providing toilet facilities. Spearman’s correlation coefficient was used to explore the relationship between income source and toilet facilities in the households. All statistical analysis was done using SPSS version 21. The findings were presented in form of tables and figures. The results reveal a significant lack of toilet facilities among the residents. Regarding the level of accessibility, most adults (79%) and children (72%) used household toilet facilities for defecation, while 14% of adults and 16% of children in the household were using toilet facilities outside the household. Open defecation near the house was more prevalent among the children (11%) than adults (6%) which shows unwillingness by most families to invest in improve toilet facilities.
Spectral Discrimination of Invasive Lantana Camara L. From Co-Occurring Species
(Elsevier, 2023) Waititu, Julius Maina; Mundia, Charles Ndegwa; Sichang, Arthur W.
Lantana Camara L. (LC) invasive species has not been successfully mapped due to inadequate spectral information. This study aimed at assessing the performance of leaf-level in-situ hyperspectral data and derived indices in discriminating LC among co-occurring species during the dry and wet seasons. In addition, the performance of simulated Sentinel-2 bands, Sentinel-2 derived indices and machine learning algorithms in discriminating it was explored. Spectrally distinct features for species discrimination were selected using the guided regularized random forest (GRRF) and their separability quantified with Jeffries–Matusita distance method. We found that ratio-based and difference indices constructed with first and second-order derivative hyperspectral reflectance wavelengths perfectly separated LC from co-occurring species in the dry and wet seasons with ≥ 97% of separability accuracy. Similarly, a set of derived ratio-based and difference Sentinel-2 indices yielded > 95% and < 80% of LC separability accuracy in wet and dry seasons respectively. The SVM with radial basis function algorithm fitted with selected continuum removed derivative reflectance (band depth) narrow-bands yielded the highest overall accuracy (OA) of 84% and a Kappa of 0.75 for the dry season while the same algorithm fitted with selected first derivative narrow-bands yielded an OA of 82% and Kappa of 0.66 for the wet season. Conversely, the regularized logistic regression yielded the highest performance (OA of 77% and Kappa of 0.62) when fitted with combined selected Sentinel-2 variables for the dry season while the gradient boosting machine (GBM) fitted with combined Sentinel-2 variables had the highest performance (OA of 75% and Kappa of 0.51) for the wet season. These findings have important implications on the upscaling of LC’s derived leaf-level indices to canopylevel and subsequent LC classification with hyperspectral and Sentinel-2 imagery datasets over heterogeneous environments.
Characterizing Rural Households’ Livelihood Vulnerability to Climate Change and Extremes in Migori River Watershed, Kenya
(Informa UK Limited, 2023) Opiyo, Stephen Balaka; Letema, Sammy; Opinde, Godwin
Sub-Saharan Africa, of which Kenya is part, is considered the most vulnerable region to climate change impacts due to its dependence on rain-fed agriculture and natural resources. Since the rural livelihood systems in Kenya are expected to bear some of the worst effects of climate change, it is imperative to assess rural households’ vulnerability to climate change impacts to facilitate the development of adaptation strategies. Therefore, this paper determines the level and sources of households’ livelihood vulnerability to climate variability in the Migori River watershed, Kenya. The Livelihood Vulnerability Index (LVI) framed within the Intergovernmental Panel on Climate Change (IPCC) vulnerability framework (LVI-IPCC) was applied. A cross-sectional household survey conducted on 318 randomly selected households was used to assess how vulnerability differs across three watershed zones, upstream, midstream, and downstream. The LVI-IPCC scores were −0.047, −0.003, and 0.008 for the upstream, midstream, and downstream zones, respectively, with significant differences noted in the scores (ANOVA, p < 0.05). Findings indicate that while the livelihoods in all three zones showed moderate vulnerability to environmental and socio-economic stressors, there are notable variations between them. The downstream households exhibit the highest vulnerability, attributed to their lower adaptive capacity, increased exposure, and heightened sensitivity. Conversely, the upstream households demonstrate the least vulnerability compared to the other zones, owing to their lower sensitivity and exposure, as well as better adaptive capacity. Policy recommendations for reducing households’ exposure to climate risks and for strengthening their adaptive capacity are discussed.
Fish Productivity Response to Water Quality Variations: A Case Study of Nyumba ya Mungu Dam, in Pangani Water Basin, Tanzania
(ije, 2023) Mangi, Halima O.; Onywere, Simon M.; Kitur, Esther C.
Fish habitat degradation, such as water pollution due to the rapid expansion of incompatible land uses, is one of the noteworthy challenges to freshwater ecosystems. Elevated contents of nutrients and contaminants in water are some of the imperative challenges. *is research was conducted to investigate the link between water qualities and 3sh productivity in the Nyumba ya Mungu Dam, whose 3shery potential had decreased by 95% between 1972 and 2018. Physicochemical characteristics, namely, temperature, pH, dissolved oxygen (DO), turbidity, total nitrogen, total phosphorus, chlorophyll a, and the water depth of 3shing net location, were assessed following standard procedure. Fish catches per unit e;ort representing 3sh biomass/productivity were monitored for twelve months from January to December 2019. Pearson’s correlation analysis indicated that 3sh catch per unit e;ort was positively and signi3cantly correlated with turbidity (r = 0.461, P < 0.01) and TP (r = 0.405, P < 0.01). Stepwise multiple regression model results indicated that turbidity, dissolved oxygen, and the depth of the 3shing net location are the statistically signi3cant predictors of 3sh catch per unit e;ort which represented 3sh biomass. Findings further indicated that the model combining turbidity and dissolved oxygen predicted a 24% change in 3sh catch per unit e;ort, whereas turbidity, dissolved oxygen, and the depth of 3shing net location contributed a 28.9% change in 3sh catch per unit e;ort. In conclusion, 3sh productivity in the NMD is limited by organic matter availability and nutrient levels that cause algae bloom occurrence. Turbidity is an indicator of organic matter availability and the e;ect of algae bloom on 3sh productivity. InCow of nutrients to the dam nourishes the algae biomass, thus creating vicious cycles on 3sh productivity as 3sh species in the dam failed to take advantage of high primary production by algae.
The Typology of Public Open Spaces: Classification and Challenges from Machakos Municipality, Machakos County, Kenya
(International Journal of Advanced Research (IJAR), 2020) Loki, Mathias; Aloyo, Paul; Majale, Christine; Kigondu, Samuel
Public open spaces form an important part of life, giving services to people and protecting the urban environment. Ineffective standards for establishment, of public open spaces have always been a stumbling block in ensuring their sustainability, hence the existence of non performing unplanned, and poorly distributed public open spaces. This study sought to establish the types of public open spaces in Machakos municipality, Machakos County. The study aimed to characterize the typologies of public open spaces in order to understand the underlying reasons for how they came to be. Primary and secondary data sources were used to get the information. Primary data gathered using questionnaires, interview schedules, observation schedules and photographs. Secondary data on the other hand was gathered through review of existing literature materials and documentations of public open spaces from the county government blueprints and policy documents. . The findings revealed that there are a number of public open spaces in Machakos Municipality, with Machakos People’s park as the most popular of these open spaces.
Spatial distribution of waste collection points and their implications on quality of life in Mombasa County, Kenya
(Elsevier, 2020) Wekisa, Ezra; Majale, Christine
Quality of life index is a measure used to describe the living environment experienced by a segment of the population. Correspondingly, waste collection and transfer are the core of waste management chain and is influenced by the four capitals of sustainability – economic capital, physical capital, environmental capital and social capital. Mombasa generates approximately 2200 tons of waste and only 65% are collected and 13% of households’ access county (local authority) waste management services due to mismanaged primary collection points. In ascertaining the link between primary collection points and quality of life, indicators used to construct the index were defined and weighting assigned based on their impact on the environment. This study employed both descriptive study approach and mixed methods involving quantitative and qualitative methods to collect and infer the data. The study showed that Mombasa County is served by nine designated collection points that are inadequate and has led to the emergence of informal collection points and exposed the residents to communicable diseases. The attitude of the residents on waste management is wanting and has exacerbated the waste management drive in the county. Correspondingly 74% of the respondents used in the study have reservations regarding the waste management conduct and practices as currently practised by the local authority. Quality of life index was arrived at with more emphasis and higher weighting on the environmental aspect. The aggregated quality of life index highlighted areas with more concentration of collection points enjoy low quality of life and converse.
Designing Institutional Arrangements for Collaborative Governance of Forests in Kenya Using a Delphi Process
(Journal of Scientific Research and Reports, 2019) Ming’ate, Felix Lamech Mogambi; Letema, Sammy; Obiero, Kennedy
The focus of the study is to examine the institutional arrangement for forests governance in Kenya to understand the important design issues that can improve their performance in the delivery of sustainable livelihoods and conserve forests as they have been previously regarded as problematic. The study uses the Delphi technique to assemble information from 46 experts with vast experience in collaborative governance of forests in developing countries. The researchers then developed four questions which were asked across all the study experts. In the second round, all the expert responded to the four open-ended questions and all the qualitative results were analyzed manually by grouping them intointerquartile ranges and only those issues that were above the 75th interquartile range were retained. In the subsequent third round of the Delphitechnique the expertsgave their answers, the responses were collated and returned to each respondent who then was invited to revise his/her estimates orto specifythe reasons for remaining outside the consensus. In the fourth and final round, again, the responses were assembled and reported back to the participants to justify his/her position, whether or not he wishes to change his/her position. The results show that the Delphi technique has the potential for studying institutional design for collaborative governance of forests. The study recommends that the important issues identified can be used to help in the formulation of collaborative governance institutional design policies
Factors Influencing Adoption of Biomass Energy Conservation Technologies in Selected Areas of Kitui County, Kenya
(Journal of Environmental Science and Engineering, 2019) Kitheka, Emily; Kimiti, Jacinta; Oduor, Nellie; Wanza, Jane; Ingutia, Celestine; Githiomi, Joseph
In Kenya, demand for biomass energy has increased due to increasing population and urbanization and high cost of alternative energy sources. This coupled with use of inefficient production and utilization technologies, has led to increased deforestation, environmental degradation and increased health impacts. In Kenya, a number of improved technologies have been developed and promoted; however, adoption still remains low. This study sought to assess factors influencing adoption of biomass energy conservation technologies in four selected areas of Kitui County, Kenya. Data were collected using a structured questionnaire and guidelines for institutional and focus group discussions. Sampling was done through purposive and stratified random sampling. Results revealed three categories of biomass energy conservation technologies: energy saving stoves (46%), woodlots (9%) and improved charcoal conversion kilns (2%). The mean percentage adoption rate in the four study areas stood at 48% with Chuluni having the highest (51%) while Kitui West had the least (46%). Agriculture (28%), forestry (26%) and NGOs (Non-Governmental Organizations)/CBOs (Community-Based Organizations) (23%) were indicated as the main sources of information, while field days (35%), community trainings (30%) and demonstrations sites (22%) were the most preferred dissemination channels. High cost of technologies, lack of awareness, financial constraints, cultural preferences, gender aspects, lack of follow up programmes and inadequate capacity to enforce implementation of existing energy policies and regulation were indicated as key constraints to adoption of technologies. The study recommends development of a joint implementation strategy and follow up programmes that will look at the cost of technologies, dissemination channels and involvement of stakeholders’ in development and dissemination of biomass energy conservation technologies.
Effect of Land tenure change on Land use in Machakos County, Kenya.
(International Cartographic Association, 2019) Baaru, Mary; Charles, K. K.
Land tenure is considered an important issue of development agenda and this has led to land allocation and titling in developing countries across continents. As a result, a massive transfer of land rights. Land tenure has been considered as one of the key factors that define patterns and changes in land use system. Due to challenges in collective ownership, Kenya has embraced this idea shifted away to individual land tenure system. This paper examines how land tenure change has influenced land use patterns in Katheka-kai Location, Machakos County for 21 years (1988- 2009), Kenya. The study area was until 1995 a ranching scheme but transformed to individual farms, providing a niche in studying land use change. Six classes identified as forests, cultivated land, savannah grassland, water bodies, built-up land, rocky areas, and bare land was used for change detection. Thematic change detection for Landsat TM and Landsat ETM+ was established using ENVI EX. This was done by selecting two images of the same scene, with same number of classes and same names at different times. During the period of 1988-2009, the major land use/cover was savannah grassland, bare land, rocky areas, and forest. Cultivated land, built-up areas, and water bodies had the least land cover. The land use/cover change has been dynamic with about 68.6% land changing from one land use to another between 1988 and 2009 (Figure 1 and 2). The 24.4% increase recorded in savanna grassland was at the expense of rocky areas, forest cover, bare land and water bodies that lost 18.7, 2.9, 2.1 and 0.7% respectively (Table 1). Despite the loss, forest cover still recorded 2.7% increase between 1988 and 2009 mostly from rocky areas (1.6%) and bare land (1.2%). Apart from becoming savanna grassland, most of the bare land was converted to rocky areas (7.6%), cultivated land (1.8%) and forests (1.2%) and this explains the 7.4% decrease in area under bare land. Cultivated land witnessed a 1.8% increase between 1988 and 2009 and was due to conversion of bare land (1.8%) and forest cover (0.6%) into cultivated land. Increase in percentage area under built-up areas (0.5%) was as result of conversion of bare land (0.2%), rocky areas (0.2%) and savanna grassland (0.1%). Water bodies changed to become savanna grassland (0.7%) and rocky areas (0.4%) and this led to 0.5% decline in land under water bodies. Savanna grassland, bare land and rocky areas are the dominating land uses/justified by the fact that the area is a rangeland initially hosting a range of wildlife animals. Increased population leads to high demand for food and housing and this explains the increase cultivation land and built-up areas. A study carried out by Gathaara et. al. (2010) in the same area reported that most of the farmers resulted in agricultural activities to meet increasing food demand as well as for economic gains. Similarly, Mundia and Muranyan (2009) reported that changing land tenure policy resulted in expansion of agricultural land. Furthermore, after subdivision and issuance of title deeds to individual members, the owner gets the rights to make land use decisions based on benefits.
Impact of Urban Forms on 3d Built-Up Intensity Expansion Rate from Aerial Stereo-Imagery
(The International Society for Photogrammetry and Remote Sensing, 2020) Mwangi, P. W.; Karanja, F. N.; Kamau, P. K.; Letema, S. C.
Urban areas have been cited to be contributors to changing climatic conditions. Conversion of vegetated areas to impervious surfaces causes an alteration of surface temperatures, where impervious surfaces absorb and store incoming radiation during the day, releasing it slowly at night. This causes the urban heat island effect where temperatures in urban areas are higher than rural areas during night. Extreme weather conditions experienced in urban areas include heat waves, intense rainfall resulting to flash floods, destruction of infrastructure facilities. The research involved the use of time-series of stereo-aerial images acquired in 1978, 2000 and 2017. Building footprints were digitized and using digital elevation models, building heights were derived and volumes calculated. Road volumes were calculated using minimum standards of road construction and the total built-up volume was determined. The ground coverage ratio (GCR) and built-up volume densities (BVD) of the built-up areas was calculated from area and volumes from road and building values. Results indicate the mean GCR and BVD in Upper Hill is within the low density range. Mean building height from 1978 to 2017 are in the low-rise range with significant rise in building height and volumes between 1998 and 2017. The 3D built-up intensity expansion rate ranged between -4.28% to 56.80% per annum with a mean of 19.6% per annum. Roads and pavements also have a significant influence on the built-up density and should therefore be considered in planning policies.
Trend and Variability in Interannual Air Temperature Over South West Mau Forest, 1985 - 2015
(International Knowledge Sharing Platform, 2020) kigomo, Mathew Kiura; Mburu, David Mwehia; Kinyanjui, James Mwangi; Thuo, Aggrey Daniel Maina; Mundia, Charles Ndegwa
Globally high altitude forest regions are considered to be more prone to rapid warming. These regions have also shown great seasonal and inter annual temperatures variability. In Kenya mean annual temperatures increased by 1.00C since 1960. Going by global trends it is plausible to argue that high altitude forest areas in Kenya might have shown great seasonal and inter annual temperatures variability over time. This study assessed interannual trend and variability as well as change point detection in average annual air temperature in South West Mau Forest, Kenya between 1985 and 2015. South West Mau Forest is an indigenous montane ecosystem with a tropical montane climate. Annual average air temperature over the South West Mau forest pointed towards climate warming of 0.01880C per year (Kendall’s tau = 0.3677, p value = 0.0033) but with low interannual variability (CV= 0.11%). A shift in the annual average air temperature of 0.3680C at p= 0.0051 was detected between 1985- 1998 and 1999- 2015. There was a weak positive anomaly in the annual average air temperature with a slope of 0.0192 and R2 = 0.3074. Overall the region experienced climate warming.
Evaluating the Relationship between Drought and Vegetation Greenness in Chyulu- Amboseli Rangeland, Kenya
(AJOL, 2020) Nyangena, J.; Onywere, S.; Shisanya, C.
Remote sensing techniques have been widely used to monitor moisture-related vegetation conditions. Vegetation vigour response to drought however is complex and has not been adequately studied using satellite sensor data. This paper investigated the time lag response of vegetation to drought in Kenya’s Chyulu-Amboseli ecosystem based on Standardized Precipitation Index (SPI) derived from monthly precipitation data for the period January 2000-October 2016 downloaded from the Climate Hazards group InfraRed Precipitation with Stations and Normalized Difference Vegetation Index (NDVI) computed from Moderate Resolution Imaging Spectro-radiometer (MODIS) pre-processed images downloaded from the University of Natural Resources and Life Sciences (BOKU) database. Statistical analysis showed that drought severity increased over the study period while corresponding vegetation conditions degenerated. Results further revealed that the relationship between drought and vegetation greenness was significant (R2 = 0.6) with 2 months optimal lag. This calls for policy makers and programme managers to integrate the lag effect in measures to cope with drought in the rangelands.

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