Impacts of Vachelia reficiens and Prosopis juliflora on the Environment of Samburu East Sub-County, Kenya

Abstract

Negative impacts of invasive plant species are a major challenge globally in the 21st Century. They have enormous environmental and economic costs. In spite of this, little is known of their impacts and management interventions. In Kenya, Samburu East Sub-County has experienced a spread of Vachelia reficiens and Prosopis juliflora. The resident community and the government are concerned on the extent of the spread and establishment of the species in the area. To address these concerns, the study aimed at analyzing their impacts on; socio-economic activities; the environment; spatio-temporal variations of impacts-, and evaluation of effectiveness of on-going interventions. To obtain quantitative and qualitative data, sequential explanatory mixed-method study design was used. Five-point perception count on a Likert scale was used to rate the magnitude of the impacts. To achieve this objectives, multistage clustered random sampling at each stage of the administrative units was used to obtain sampling design frame. Probability and non-probability sampling methods were employed to obtain data using structured research instruments. Questionnaire validity and reliability were confirmed before data collection. Inferential and descriptive statistics were used to analyze data. The result showed that impact of Vachelia reficiens were higher in magnitude than of Prosopis juliflora and the effective method of interventions was cutting. The results were statistically significant based on the chi square test analysis at p < 5%. Therefore, the two plant species have statistically significant negative impacts on the socio-economic and environmental systems and impacts differ over space and time. The study recommends management and policy measures for urgent attention in order to safeguard biodiversity and community livelihoods. Implementation of the recommendations by state and non-state actors will enhance environmental sustainability in the sub-county.