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Table 1. Significant level (P ) of main effects and interactions of topsoil depth and crop species on grain yield (2016, 2017, 2018), growth parameters (2017), nutrient uptake (2017), and concentrations of available nutrients (N, P and K) and activities of enzymes in the rhizosphere soil (2017) of maize at the jointing (V7) and milk (R3) stages, and of soybean at the initial flowering (R1) and seed-filling (R6) stages.