Pig slurry in carpet grass pasture: Yield and plant-available nitrogen

Abstract

A B S T R A C TThis study evaluated the response of carpet grass to pig slurry fertilization in order to estimate the agronomic efficiency and the plant-available nitrogen (N) of such manure. A field test was conducted during two years, following a randomized block design with six replicates of the treatments: 0, 100, 200, 300, 400 and 500 kg N ha ). The average agronomic efficiency of the manurewas 15 kg DM kg -1 N and it was lower than that found with ammonium nitrate (27 kg DM kg -1 N).The estimated plant-available N of the pig slurry was similar between the growing years. The N fraction of this manure available to the pasture was 0.64 (2008-09) and 0.60 (2009-10).Dejeto líquido de suínos em pastagem de grama-tapete: Produção e nitrogênio disponibilizado R E S U M O Este estudo avaliou a resposta da grama-tapete à aplicação de dejeto líquido de suíno para determinar a eficiência agronômica e estimar a disponibilidade de nitrogênio desse esterco. O experimento foi realizado em condições de campo durante dois anos, em delineamento em blocos ao acaso, com seis repetições dos seguintes tratamentos: 0, 100, 200, 300, 400 e 500 kg N ha -1 ano

Residual effect of pig slurry on common carpet grass pasture

“…Whereas in this study (2010)(2011), DMY increased by 3.98 kg DM ha − ¹ year -1 for each m − ³ PS applied (Figure 1), during the period of application (2008)(2009)(2010) each m³ PS contributed an average 25,57 kg DM ha¹ year − ¹ (Brustolin et al, 2016). Thus, the residual nitrogen fertilizer did not provide enough N to maximize DMY, which reached a maximum value of approximately 4,500 kg DM ha − ¹ year − ¹ one year after the application of PS, compared to an average DMY of 10,019 kg DM ha − ¹ year − ¹ during 2008-2010(Brustolin et al, 2016.…”

“…Thus, the residual nitrogen fertilizer did not provide enough N to maximize DMY, which reached a maximum value of approximately 4,500 kg DM ha − ¹ year − ¹ one year after the application of PS, compared to an average DMY of 10,019 kg DM ha − ¹ year − ¹ during 2008-2010(Brustolin et al, 2016. Because roughly 60% of the N applied as PS was available to this pasture in 2008-2010(Brustolin et al, 2016, it may have accumulated as microbial biomass or other relatively less recalcitrant soil organic compounds. Moreover, some of the PS ammonium-N may have been lost or fixed on clays shortly after its application and some of the organic-N may have been allocated in stems, leaves, and roots, which is made available over time through senescence.…”

“…The treatments consisted of five PS application rates, calculated to provide 100, 200, 300, 400, and 500 kg ha -1 year -1 N, one ammonium nitrate (AN) application rate equivalent to 200 kg ha -1 N, or no nitrogen fertilization (PS0 + AN0) (Brustolin et al, 2016). The soil in the experimental area is an Oxisol, with clay testure in the 0-0.05 m layer.…”

“…Similar results were reported in studies with Axonopus spp. (Miranda et al, 2012;Brustolin et al, 2016) following PS and AN applications. In these studies, the DMY, at an ammonium nitrate application rate of 200 kg ha − ¹ N, was equivalent to a PS rate calculated to provide 300 kg ha − ¹ N. These results indicate that release of N from manure was 50% smaller than from ammonium nitrate.…”

“…Pig slurry (PS) is an organic alternative to chemical nitrogen (N) fertilizers that can increase production of winter and summer crops (Seidel et al, 2010;Moraes et al, 2014;Basso et al, 2016) and of cover crops (Aita et al, 2006). Many studies have found an increase in dry matter yield (DMY) of pastures in response to PS fertilization (Vielmo et al, 2011;Miranda et al, 2012;Zanine & Ferreira, 2015).…”