Agricultural Land Degradation in Kenya

Abstract

Arid and semi-arid drylands cover approximately over 80% of Kenya's landmass and are home to almost 30 and 70% of the human and livestock populations, respectively. Pastoral livestock--crop production systems constitute the main economic activity and source of livelihood. In Kenya, land degradation has widely been considered as a major environmental challenge threatening the livelihoods of over 12 million people living in degraded lands. Nearly 80% of Kenya's landmass is affected by land degradation. It has been estimated that approximately 30--40% of the arid and semi-arid lands are rapidly being lost through degradation and an additional 2% have completely been degraded. The total economic value of land degradation in Kenya was at 1.3 billion USD annually between 2001 and 2009. Principal degradation processes in the marginal arid and semi-arid environments in Kenya include salinization, soil compaction, vegetation degradation, and soil erosion. Soil loss in these dryland zones mainly occurs when vegetation cover is removed exposing the soil to the agents of erosion, i.e., water and wind. Arid and semi-arid environments are particularly vulnerable to degradation because the soils are characterized by a poor structure exacerbated by scarce vegetation cover. The main causes of land degradation in these dryland environments in Kenya include overgrazing, woodland deforestation, poor rainfed and irrigation agricultural practices, and mineral mining activities. Land degradation process in these marginal lands is aggravated and accelerated by the effects of climate change and variability (recurrent droughts and floods) and increased human population. Increased human population has continued to exert tremendous pressure on the Kenyan dryland resources. However, it also serves as the main driver and valuable resource in reversing degradation at farm and landscape scales through soil conservation and sustainable land management practices such as conservation agriculture, dryland agroforestry, indigenous grass reseeding, and rangeland enclosures. These practices among pastoral and agropastoral communities in the Kenyan drylands have generally been effective in combating land degradation and enhancing ecosystem services. Despite the numerous climatic and socioeconomic challenges in implementing these practices in dryland environments, they remain a viable option for enhancing sustainable crop and livestock production in the arid and semi-arid zones in Kenya. Combating land degradation in the Kenyan drylands can best be achieved through the continued involvement of the community in the selection and implementation of appropriate practices to address site- and/or landscape-specific challenges.