Phosphorus Balance in Sandy Soil Subjected to 12 Years of Successive Applications of Animal Manure and Mineral Phosphate Fertilizer in Subtropical Climate

Abstract

Assessing the phosphorus (P) balance in agricultural soils is crucial for optimizing its use and reducing contamination risks. The objective of this study was to evaluate the impact of different animal wastes on the distribution of P in soil profiles subjected to 12 years of successive applications of animal wastes and mineral phosphate fertilizer, within a crop rotation system under no-till system. The study was conducted from 2004 to 2016 in the southern region of Brazil. The treatments were the applications of pig slurry (PS), cattle slurry (CS), pig deep-litter (PD), mineral fertilizer (MF), and a control treatment without application. The highest accumulation of P and its movement was observed in the 0–40 cm layer, in the soil submitted to applications of all P sources. The inputs of P via MF, CS, PS, and PD promoted the accumulation of 18, 42, 48, and 100 kg P ha−1 year−1. The P mass balance showed that between 77 and 98% of the P added by animal manure and MF was accounted for in grain exports (17–34%), soil storage (41–72%), and post-harvest residues (<1%), with the remaining 2–33%, unaccounted for, which was attributed, especially, to P transfer at the soil surface.