Intercropping camphor basil shrubs with selected food crops for ecosystem services in the upper midland agroecological zone of Western Kenya
Paper Details
Intercropping camphor basil shrubs with selected food crops for ecosystem services in the upper midland agroecological zone of Western Kenya
Abstract
Agroecology practices through a nexus of intercropping, biodiversity conservation and ecosystem services (ES) is gaining traction globally. However, they remain insufficiently documented in Kenya, which hampers their adoption by smallholder farmers and policymakers. This research examined two shrub-based intercropping systems to assess their potential for enhancing food security within a landscape adjacent to the protected Kakamega forest ecosystem. The study followed standard agronomic protocols for sowing during the 2023 cropping season under rain-fed conditions, using a Randomized Block Design. Soil health parameters, including Nematode counts, were measured before planting and after harvesting the intercrops. The advantages of intercropping in terms of biophysical yield were evaluated using Land Equivalent Ratios (LER) and percentage Land Saved (% LS). Crop resilience was assessed through Partial LERs, while overall intercropping performance was analyzed using the Pareto principle. The three-tier intercropping systems demonstrated a 70% reduction in land use while achieving higher yields (ranging from 558.3 kg/ha to 6432 kg/ha) compared to the two-tier cereal maize/bean systems, which yielded 4022.5 kg/ha with a 57.4% LS. Among the combinations of three crops i.e. Camphor basil, Cowpeas, NERICA rice, Maize, or Soybeans—those involving Camphor basil and Cowpeas showed the highest resilience, with PLER values of 1.597 and 1.23 respectively. Notably, soil health status with destructive nematode counts exhibited a significant decline (p<0.05) for Pratylenchus sp. and Meloidogyne sp. Overall, a shrub-based three-tier intercropping system offers greater ecosystem services compared to traditional cereal/legume systems, hence suitable for adoption by farmers at a broader scale.
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