Assessing the Underlying Drivers of Change over Two Decades of Land Use and Land Cover Dynamics along the Standard Gauge Railway Corridor, Kenya

Abstract

Land cover has been modified by anthropogenic activities for thousands of years, although the speed of change has increased in recent decades, particularly driven by socio-economic development. The development of transport infrastructure can accelerate land use land cover change, resulting in impacts on natural resources such as water, biodiversity, and food production. To understand the interaction between land cover and social–ecological drivers, changing land cover patterns and drivers of change must be identified and quantified. This study documents land cover dynamics along the Standard Gauge Railway (SGR) corridor in Kenya and evaluates the underlying drivers of this change from 2000 to 2019. The study utilised GIS and remote sensing techniques to assess the land use and land cover changes along the SGR corridor, while correlational and regression analyses were used to evaluate various drivers of the changes. Results showed that built-up areas, bare lands, water bodies, croplands and forests increased by 144.39%, 74.73%, 74.42%, 9.32% and 4.85%, respectively, while wetlands, grasslands and shrub lands reduced by 98.54%, 67.00% and 33.86%, respectively. The underlying drivers responsible for these land use and land cover dynamics are population growth, urbanisation, economic growth and agro-ecological factors. Such land cover changes affect environmental sustainability, and we stress the need to adequately identify and address the cumulative social and environmental impacts of mega-infrastructure projects and their interacting investments. The findings of this study provide an evidence base for the evaluation of the social–ecological impacts of the SGR and the implementation of best practices that will lead to enhanced sustainability in the development corridors in Kenya and beyond.

Quantifying the Environmental Impact of Standard Gauge Railway (SGR) on Land Cover Changes along the Nairobi-Kiambu Corridor from 2016 to 2019

“…This has led to increased pressure on agricultural lands, shrub land, grassland and other resources which are already limited [17]. There are several reasons for the increase in urbanization, however, none has had such an impact by the devolution of resources over the past 20 years, initially initiated by the Constituency Development Fund in 2003 [18], and later the implantation of the devolved system of governance in 2013 [6] The ripple effects of this have been the increase in the construction of buildings, roads, and railways; leading to the creation of more employment opportunities [18]. The resulting impact has been a rapid increase in the urban population, for example, the urban population in Kenya in 2009 was 12.84 million [18], this has risen, and by 2019 the population was 14.83 million KNBS, 2019.…”

“…The SGR is not an exception and there have been reports of negative ecosystem impacts of the SGR. In this case, disruption of movement and migration of wildlife, behavioral modification among species, bisections of basins and watersheds [5], and the physical disruption of the structure and compositions of ecosystems [6]. Similarly, there has been an increase in water, soil, and air pollution, grassland fires, and alteration of predator-prey relationship [7].…”

“…There is thus a need to understand how railway line impacts the environment to have effective mitigation measures, to contribute to planning and policy on future infrastructure projects, and finally to contribute to Kenya's obligation to the international bodies on climate change mitigation [10]. Moreover, previous studies on SGR have been mostly socioeconomic studies, for example, [6] conducted a reconnaissance study to access the ecological impacts of SGR. Likewise, Geographic Information System (GIS) studies done so far have focused on the open/sparse areas such as parks and rural regions.…”

In memory of Dr Tobias Nyumba

“…His passion for elephant conservation (Nyumba et al, 2020) and for ensuring there remained space for wildlife as Kenya continued to change and evolve was obvious to anyone who was lucky enough to meet him. Following his PhD at the University of Cambridge, Tobias worked as a Postdoctoral Fellow on the Development Corridors Partnership at the African Conservation Centre, and University of Nairobi from 2017 until March 2022 where he was particularly looking at the impact of developing transport infrastructure on elephants and other wildlife (Nyumba et al, 2021) and the impact of large infrastructure projects such as the Standard Gauge Railway on the vital resources (Sang et al, 2022). Tobias thereafter started as a Marie‐Curie Skłodowska Fellow in the Department of Environment and Geography at the University of York, leading his ‘Space for Giants’ project.…”