CHARACTERIZATION OF THE ENVIRONMENTAL EFFECTS OF CLIMATE CHANGE AND VARIABILITY ON THE BIOPHYSICAL AND SOCIO-ECONOMIC SYSTEMS USING GEO-INFORMATION TECHNOLOGY AT THE MAU FOREST COMPLEX, NAROK COUNTY, KENYA

Abstract

Climate change and variability are immediate and severe threats to the environment and socio-economic systems. The study was carried out within the Mau Forest Complex (MFC), Narok County to characterize the effects of climate change and variability (CCV) on biophysical and socio-economic systems. The MFC is the largest remnant closed canopy Afromontane forest in East Africa and a critical catchment area for many river basins. Unfortunately, this socio-ecological system is faced with unprecedented onslaught threatening its existence. The study was undertaken based on the premise that such resources are highly susceptible to climatic variations and unsustainable anthropogenic activities triggered by such variations and extreme weather events. Longitudinal and cross-sectional research designs with mixed methods were used to infer results on Landsat imagery, climate variables and household survey data. Climate and satellite imagery data spanning 26 years were obtained from Kenya Meteorological Department and United States Geologic Survey respectively. The satellite images were processed and subjected to unsupervised classification and NDVI thematic maps creation. Change detection analyses were performed through post classification and NDVI image differencing methods to produce land cover/use thematic maps. Household survey sample size was calculated based on probability proportional to estimated size. Proportionate stratified multistage clustered sampling and snowball sampling for key informant interviews were used to determine the sample respondents. Evidence of association and significance tests between variables were measured using Spearman’s Chi-square (χ2 ) test of independence and generalized linear model. The results indicated increasing precipitation variability and declining overall precipitation trend. The observed variability in extreme temperature events indicated warming tendencies with an increasing overall trend in mean annual temperature. Satellite imageries classification results showed that dense forest cover significantly reduced while other land cover/use showing an increasing trend. NDVI thematic maps revealed a reduction in vegetation vigour. Household survey results revealed that majority of the respondents were aware of CCV while the socio-economic systems are vulnerable to the impacts of CCV as evidenced by existence of extreme climate related events such as flash floods, droughts, land/mudslides and extreme temperatures leading to environmental degradation, deforestation, agricultural land expansion and other unsustainable land uses. The resulting impacts to the biophysical and socio-economic systems in the area were linked to crops yield failure, land use conflicts, high prices and shortage of farm produce, food insecurity, diseases and deaths. The national and Narok County government must devote their resources in educating and informing the communities about all CCV’s aspects in all sectors through tailor made educational programmes, awareness and sensitization campaigns, incentive environmental conservation programmes, strengthening adaptive capacity and mitigation strategies, formulation and implementation of adequate adaptation and mitigation policies such as afforestation and reforestation, relocating people from the encroached and areas with contested settlement, enhance sustainable charcoal production, boost food production with minimum impacts, agroforestry, enhance the use of traditional knowledge, poverty alleviation and livelihoods improvement strategies, invest in social capital systems and adopt measures to curb soil erosion and climate smart technologies to help cope with the adverse impacts of CCV.