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Climate change poses a threat to crop production and livelihoods of rural farming communities in Kenya, a majority of whom are mainly dependent on rain-fed agriculture. The purpose of this study was to examine farm-level adaptation responses towards climate change and their influencing factors, using a case study of western Kenya. Structured questionnaire was administered to 210 farmers in selected locations in the region where households farm maize as the main crop. Logistic and multiple linear regression models were used to ascertain the factors that influence farmers’ adaptation practices. The results indicate that farmers perceived climate change as being responsible for the reduction in crop yield and production, crop failure and increase of fallow farms. The major adaptation strategies undertaken by the farmers included change in planting dates by either planting early or late during a season, diversification of crops, growing early maturing cultivars, use of drought-tolerant varieties and timely planting. The key determinants of adaptation strategies by the farmers included farm size, income and extension training. Understanding farmers’ responses to climate change in rain-fed crop production systems could assist in planning adaptation strategies towards sustainable crop production.

Climate and environmental change are critical factors affecting water resources, irrigation and farming systems in Ethiopia as most of the population and the country’s economy depend on agriculture...

Impacts of climatic and non-climatic risks are on the rise in the major maize-growing counties of western Kenya. We conducted a questionnaire survey of sampled maize farmers in Nandi, West Pokot, U...

Climate change and variability are a major threat to the agricultural sector globally. It is widely accepted that the changes in temperature, rainfall patterns, sea water level and concentration of CO2 in the atmosphere will have the most devastating impacts on agricultural production. This paper examines the past and future crop production and food security in Kenya under variable climate. From the review, it is evident that the country is already experiencing episodes of climate change, manifested by seasonal changes in precipitation and temperature of varying severity and duration despite overreliance on rain-fed agriculture. The findings also reveal that climate change would continue to negatively affect crop production and food security to the already vulnerable communities in the arid and semi-arid areas. Future projections also indicate that climate variability will likely alter cropping patterns and yields in several regions. As the country is faced with a high population growth rate and rapid urbanization, crop production and food security systems need to become more adaptive as uncertainties of projected climate variability and change unfold. This study is important in providing decision makers and interested stakeholders with a detailed assessment of climate impacts and adaptation strategies geared towards improved crop production and food security.

The western region of Kenya is experiencing remarkable land changes resulting from population growth and related impacts. The study used remote sensing and GIS techniques to analyze the land use/co...

Deforestation poses a threat to sustainability of forest ecosystem services and socio-economic development in many parts of Kenya. Understanding the trend and extent of forest cover changes and the underlying driving forces over time is pertinent for sustainable management of ecosystems. However, in many parts of the country, such information is still somewhat unknown due to limited data availability for multi-temporal analysis. This paper focuses on western Kenya, a major agricultural region of biodiversity and water catchments that are under threat from forest cover dynamics. The study analyses the status of the forests in the region with the aim of determining the areal extent of coverage, trends in forest cover, drivers of change and associated impacts of deforestation. To achieve these objectives, remote sensing techniques were used to undertake supervised classification on Landsat images of 1995, 2001, 2010 and 2017 with classification scheme of forest and non-forest land cover classes. The results of the study showed that the changes in forest cover varied over time and space. There was considerable net gain in forest areas by about 43% between the period 1995–2001, and thereafter, a continuous decrease ending in a 12.5% loss by 2017. Deforestation in the region is caused by a combination of complex factors that include population pressure, politics and failures in implementation of policy. This study determined the forest cover dynamics and driving forces across diversified sub-basins, an approach that had not been used by previous studies in the region. Thus, the findings will provide valuable information for decision making pertaining to integrated land use and catchment management in order to realize the enormous benefits of sustainable forest ecosystems. The information will not only be important to the study area, but equally applicable to similar tropical regions.

The use of crop modelling in various cropping systems and environments to project and upscale agronomic decision-making under the facets of climate change has gained currency in recent years. This paper provides an evaluation of crop models that have been used by researchers to simulate maize growth and productivity. Through a systematic review approach, a comprehensive assessment of 186 published articles was carried out to establish the models and parameterization features, simulated impacts on maize yields and adaptation strategies in the last three decades. Of the 23 models identified, CERES-maize and APSIM models were the most dominant, representing 49.7% of the studies undertaken between 1990 and 2018. Current research shows projected decline in maize yields of between 8% - 38% under RCP4.5 and RCP8.5 scenarios by the end of the 21st century, and that adaptation is essential in alleviating the impacts of climate change. Major agro-adaptation options considered in most papers are changes in planting dates, cultivars and crop water management practices. The use of multiple crop models and multi-model ensembles from general circulation models (GCMs) is recommended. As interest in crop modelling grows, future work should focus more on suitability of agricultural lands for maize production under climate scenarios.

Climate variability can influence the dynamics of aquatic invasive alien plants (AIAPs) that exert tremendous pressure on aquatic systems, leading to loss of biodiversity, agricultural wealth, and ecosystem services. However, the magnitude of these impacts remains poorly known. The current study aims to analyse the long-term changes in the spatio-temporal distribution of AIAPs under the influence of climate variability in a heavily infested tank cascade system (TCS) in Sri Lanka. The changes in coverage of various features in the TCS were analysed using the supervised maximum likelihood classification of ten Landsat images over a 27-year period, from 1992 to 2019 using ENVI remote sensing software. The non-parametric Mann–Kendall trend test and Sen’s slope estimate were used to analyse the trend of annual rainfall and temperature. We observed a positive trend of temperature that was statistically significant (p value &lt, 0.05) and a positive trend of rainfall that was not statistically significant (p values &gt, 0.05) over the time period. Our results showed fluctuations in the distribution of AIAPs in the short term, however, the coverage of AIAPs showed an increasing trend in the study area over the longer term. Thus, this study suggests that the AIAPs are likely to increase under climate variability in the study area.

This study examined the impact of land use/cover changes on soil erosion in western Kenya in the years 1995 and 2017. The study used the GIS-based Revised Universal Soil Loss Equation (RUSLE) modelling approach and remote sensing assessment. The results showed that the average soil loss through sheet, rill and inter-rill soil erosion processes was 0.3 t/ha/y and 0.5 t/ha/y, in the years 1995 and 2017, respectively. Of the total soil loss, farms contributed more than 50%, both in 1995 and 2017 followed by grass/shrub (7.9% in 1995 and 11.9% in 2017), forest (16% in 1995 and 11.4% in 2017), and the least in built-up areas. The highest soil erosion rates were observed in farms cleared from forests (0.84 tons/ha) followed by those converted from grass/shrub areas (0.52 tons/ha). The rate of soil erosion was observed to increase with slope due to high velocity and erosivity of the runoff. Areas with high erodibility in the region are found primarily in slopes of more than 30 degrees, especially in Mt. Elgon, Chereng&rsquo, anyi hills and Elgeyo escarpments. This study forms the first multi-temporal assessment to explore the extent of soil erosion and seeks to provide a useful knowledge base to support decision-makers in developing strategies to mitigate soil erosion for sustainable crop production.

This study is aimed at evaluating alternative designs of waste stabilization ponds (WSPs) and constructed wetlands (CWs) for Kaputiei Housing Estate consisting of 2000 low cost housing units in Kenya. The entire analysis was carried out by simulating the effectiveness and purification efficiencies of WSPs and CWs in terms of Biological Oxygen Demand (BOD) reduction and faecal coliform (FC) removal under different scenarios of water treatment systems that included Re-sizing of the initial sewage treatment system, optimizing the design of the initial system and design of hybrid system for the estate. The graphic comparison of the simulated parameters under different scenarios showed that a hybrid design that combines both the WSPs and CWS provides an effluent BOD of 20 mg/l and 195 FC per 100 ml that meets the standard effluent discharge that is acceptable for unrestricted crop irrigation and thus will be reused in the housing estate for kitchen gardening and agroforestry.

Climate change and variability are projected to alter the geographic suitability of lands for crop cultivation. In many developing countries, such as Kenya, information on the mean changes in climate is limited. Therefore, in this study, we model the current and future changes in areas suitable for rainfed maize production in the country using a maximum entropy (MaxENT) model. Maize is by far a major staple food crop in Kenya. We used maize occurrence location data and bioclimatic variables for two climatic scenarios-Representative Concentration Pathways (RCP) 4.5 and 8.5 from two general circulation models (HadGEM2-ES and CCSM4) for 2070. The study identified the annual mean temperature, annual precipitation and the mean temperature of the wettest quarter as the major variables that affect the distribution of maize. Simulation results indicate an average increase of unsuitable areas of between 1.9&ndash, 3.9% and a decrease of moderately suitable areas of 14.6&ndash, 17.5%. The change in the suitable areas is an increase of between 17&ndash, 20% and in highly suitable areas of 9.6% under the climatic scenarios. The findings of this study are of utmost importance to the country as they present an opportunity for policy makers to develop appropriate adaptation and mitigation strategies required to sustain maize production under future climates.

In Kenya, environmental impact assessment (EIA) has been used to ensure that environmental management is integrated into project planning and decision-making with a view of achieving ecologically sustainable development. Best-practice EIA identifies environmental risks, lessens resource use conflicts by promoting community participation, minimizes adverse environmental effects, informs decision-makers, and helps lay the base for environmentally sound projects. In the integration of an EIA, due considerations are made in all stages of a project, from exploration and planning through construction, operations, decommissioning, and beyond site closure. Therefore, this chapter brings out an in-depth understanding of the EIA in the Kenyan context. Some of the key issues looked into are the goals and principles of the EIA, the EIA process, public consultation and participation in environmental assessment, social dimensions in environmental assessment, and the legislative and regulatory framework for environmental management in Kenya.