Decomposição e liberação de N, P e K de esterco bovino e de cama de frango isolados ou misturados

Abstract

RESUMOA utilização de resíduos orgânicos de origem animal na adubação das culturas demanda informações sobre a dinâmica de decomposição e mineralização de nutrientes neles contidos. Este trabalho objetivou avaliar a decomposição e a liberação de N, P e K dos resíduos orgânicos esterco bovino e cama de frango isolados ou misturados, em Argissolo Vermelho-Amarelo, da região de Tabuleiros Costeiros paraibanos. O experimento foi conduzido em delineamento experimental de blocos casualizados, utilizando-se o método das sacolas de decomposição (litterbag), com os tratamentos arranjados em esquema fatorial 3 × 2 × 6, referentes a três resíduos orgânicos: esterco bovino (EB), cama de frango (CF) e a mistura desses resíduos na proporção de 1:1, denominada de esterco misto (EM); duas camadas de incorporação (0-10 e 10-20 cm); e seis períodos de avaliação (0, 30, 90, 150, 210 e 270 dias após a aplicação -DAA) com três repetições. Os resultados revelaram que a profundidade de incorporação não influenciou a decomposição dos resíduos EB e EM, que essa foi mais rápida na CF (0,0035 g dia -1 ), mais lenta no EB (0,0010 g dia -1 ) e ocorreu numa velocidade intermediária no EM (0,0020 g dia -1 ). Houve liberação mais rápida de N no EM (0,0011 g dia -1 ), de P no EB (0,0040 g dia -1 ) e de K na CF (0,0025 g dia -1 ), com tendência de aumento na liberação de N na CF e de P em todos os resíduos com a incorporação desses na camada de 10-20 cm. Após 270 DAP, estimou-se que a liberação de nutrientes pelos resíduos EB, CF e EM, em relação ao teor inicial, foi de 5,0; 15,0; e 28,0 %, para N; 80,0; 68,0; e 47,0 %, para P; e 20,0; 53,0; e 32,0 %, para K. Em valores absolutos, esses percentuais representaram,

Growth and Regrowth of Neem After Cutting in Saline - Sodic Soil Treated With Organic Inputs

“…The highest values obtained for bovine manure treated plants (Figure 1) are responses to higher nutrient concentrations compared with biofertilizers (Table 2) and to the action of manure as a soil physical conditioner. Manure provides increased porous space to the radicular system (DUNJANA et al, 2012) and improved soil fertility (BENBOUALI et al, 2013;SILVA et al, 2014), resulting in greater vegetative growth compared with soil treated with biofertilizers diluted in water. The superiority of the chemically enriched biofertilizer over the common fertiliser is due to its additional components such as plaster (a source of calcium and sulphur) (LEITE et al, 2010), cow's milk (rich in proteins, vitamins, calcium, phosphorus, potassium, magnesium and zinc) (NASCIMENTO et al, 2010) and molasses (a source of sugars, phosphorus, potassium, calcium, magnesium, sulphur and iron) (COPERSUCAR, 1988).…”

“…Despite these advantages, studies on the prolonged effect of these organic inputs in reducing soil sodicity and plant productive performance are still scarce. According to Silva et al (2014), bovine manure slowly releases nutrients to the soil, while Marrocos et al (2012) state that liquid biofertilisers act quickly, with the majority of their nutrients available only during the first fifteen days post application.…”

Enriched animal manure as a source of phosphorus in sustainable agriculture

“…Study of Behera et al (2018) and Coletto et al (2015) also used PCs to show nutrient dynamics over time in soil. Applications of animal manure take 90 days to increase the content of nutrients in the soil, with the first 30 days showing a greater release rate and a subsequent decline (Silva et al 2014). The remaining nutrients in animal manure take more time to be released in the soil as long as 2.5 years (Hoffmann et al 2001), but this will depend greatly on the quality of animal manure (Azeez and Averbeke 2010;Silva et al 2014).…”

“…Applications of animal manure take 90 days to increase the content of nutrients in the soil, with the first 30 days showing a greater release rate and a subsequent decline (Silva et al 2014). The remaining nutrients in animal manure take more time to be released in the soil as long as 2.5 years (Hoffmann et al 2001), but this will depend greatly on the quality of animal manure (Azeez and Averbeke 2010;Silva et al 2014). According to Tripetchkul et al (2012), greater decomposition of organic matter occurs within the first 2 weeks of the thermophilic phase in organic residues with a low C/N ratio.…”

“…The results of CoM characterized it as a manure of slow decomposition with 28% of the material decomposed within 90 days. Slow decomposition of CoM in soil was presented by the study of Azeez and Averbeke (2010) and Silva et al (2014). The increase in organic matter temporally promotes an adsorption of P in soil (Muraishi et al 2011;Maciel et al 2015;Abreu et al 2016), with a lower nutrient loss by run off and leaching while maintaining an optimal condition of pH, soil moisture and soil biological activity (Moreti et al 2007).…”