Physical properties and organic carbon content of a Rhodic Kandiudox fertilized with pig slurry and poultry litter

The impact of pig slurry and poultry litter fertilization on soils depends on the conditions of use and the amounts applied. This study evaluated the effect of organic fertilizers after different application periods in different areas on the physical properties and organic carbon contents of a Rhodic Kandiudox, in Concordia, Santa Catarina, in Southern Brazil. The treatments consisted of different land uses and periods of pig and poultry litter fertilization: silage maize (M7 years), silage maize (M20 years), annual ryegrass pasture (P3 years), annual ryegrass pasture (P15 years), perennial pasture (PP20 years), yerba mate tea (Mt20 years), native forest (NF), and native pasture without manure application (P0). The 0-5, 5-10 and 10-20 cm soil layers were sampled and analyzed for total organic carbon, total nitrogen and soil physical properties such as density, porosity, aggregation, degree of flocculation, and penetration resistance. The organic carbon levels in the cultivated areas treated with organic fertilizer were even lower than in native forest soil. The organic fertilizers and studied management systems reduced the flocculation degree of the clay particles, and low macroporosity was observed in some areas. Despite these changes, a good soil physical structure was maintained, e.g., soil density and resistance to penetration were below the critical limits, whereas aggregate stability was high, which is important to reduce water erosion in these areas with rugged terrain in western Santa Catarina, used for pig and poultry farming. O impacto do uso de dejetos de suínos e cama de aves sobre o solo depende das condições de uso e das quantidades adicionadas. Neste estudo, avaliou-se o efeito da aplicação de fertilizantes orgânicos em diferentes áreas e tempos de aplicação sobre atributos físicos e teores de carbono orgânico de um Nitossolo Vermelho eutroférrico, em Concórdia, SC. Os tratamentos abrangeram diferentes usos do solo com aplicação de dejetos de suínos e cama de aves, a saber: milho para silagem (M7 anos), milho para silagem (M20 anos), pastagem de azevém (P3 anos), pastagem de azevém (P15anos), pastagem perene (PP20 anos), erva-mate (Mt20 anos), mata nativa (NF) e pastagem nativa sem aplicação de dejetos (P0 anos). As amostras de solo foram coletadas nas camadas de 0-5, 5-10 e 10-20 cm e analisadas em relação aos teores de carbono orgânico total e nitrogênio total e às propriedades físicas do solo, como densidade, porosidade, agregação, grau d