Climate Change Induced Soil Compaction: Evaluating the Adaptation Measures to Enhance Maize Yields in a Tropical Humid Acidic Soil, Nigeria

Compaction of agricultural soils is a great concern for farmers within the tropics as climate change and poor farm practices severely affect the soil and exacerbate food insecurity in the area. The study investigated the responses of soil nutrients and maize yields to soil compaction parameters (bulk density, surface penetration resistance, gravimetric, soil water content) and management (tillage, mulching, fertilizer) in acidic soil, in Nigeria. We hypothesized that climate change and tillage promote soil compaction, whereas mulching increases mineralization of organic carbon, N, P, and K contents which consequently elevates maize yields. The study comprises of seven treatments: mulch (M), fertilizer (F), tillage (T), mulch and fertilizer (MF), tillage and mulch (TM), tillage and fertilizer (TF), and unmanaged (U) under early and late growing seasons. The mineral fertilizer NPK 12:24:12 used were urea, calcium superphosphate, and potassium sulfate respectively. Data were collected and analyzed based on 4 replicates using appropriate methods. Results showed that in the prevailing weather status, tillage had the highest dry bulk density and lowest soil water content, whereas unmanaged plots recorded the highest resistance to root penetration. Joint treatment (such as tillage and fertilizer, tillage and mulching, and fertilizer and mulching) revealed the highest soil nutrients concentrations and maize yields, relative to unmanaged and tillage. The applied treatments significantly affected all the investigated soil nutrients in 2014 growing season. A thorough knowledge of the relationship between climate change, soil compaction and nutrient processes is fundamental in solving the problems of poor yields in Nigeria. This study has demonstrated that improved soil fertility and food could be secured by mitigating the impacts of climate change induced soil compaction through the adoption of proper conservation agricultural practices in the study area.