Influence of Water Borehole Development on Rangeland Ecosystem Dynamics in Amballo Location, Obbu Ward, Moyale Sub-County, Marsabit County, Kenya

Abstract

Sustainable management of arid and semi-arid rangelands is essential for maintaining ecosystem health and supporting pastoral livelihoods. This study examined the influence of water infrastructure development on rangeland ecosystem dynamics in the Amballo location of Obbu Ward, Moyale Sub-County, Marsabit County, Kenya. A mixed-methods approach integrating vegetation surveys, remote sensing and household interviews was employed. Vegetation data were collected from transects established near the borehole and a control site, while Landsat imagery from 2000, 2007, and 2020 was used to assess long-term vegetation cover changes. Data were analyzed using descriptive statistics, two-sample t-tests, and the Shannon–Wiener diversity index. The findings showed significant reductions in woody plant density ( p = 0.006) and herbaceous biomass (p = 0.013) near the borehole compared with the control site. Plant diversity was also lower near the water source (H′ = 2.20) than in the control area (H′ = 2.86), indicating increased dominance of disturbance-tolerant species. Remote sensing analysis revealed a 16.97% decline in open grassland and a 17.60% increase in bare land between 2000 and 2020, suggesting progressive rangeland degradation. Household responses identified livestock concentration, overgrazing, trampling, tree harvesting, drought, and climate variability as key drivers of vegetation change. The study concludes that while water infrastructure improves water access and support pastoral livelihoods, they also contribute to localized degradation by altering livestock distribution and increasing grazing pressure around water points. Improved grazing management, strategic water point planning and restoration of degraded areas, are recommended to promote sustainable pastoralism.