ABSTRACT Strategies that aim to condition the soil positively impact ruminant production systems on pasture. The production of litterfall is directly responsible for improvements in the soil's chemical, physical, and biological characteristics. The objective of this study was to quantify and qualify the litterfall deposition of the Silvopastoral System with Eucalyptus (SSP) to compare with Semideciduous Seasonal Forest (FL) and Monoculture Pasture System (MN), as well as the decomposition of deciduous material. For this, 12 litterfall collectors were placed in each ecosystem, where the deposition of deciduous material was measured and stratified every 28 days for 11 months. Litterfall decomposition was evaluated using the litterbags method. The total litterfall production over the evaluated months for SSP, FL, and MN were 10.74, 7.17, and 1.01 t ha-1, respectively. The decomposition constant (k) for SSP and FL were 0.0021 and 0.0025 g g-1 day-1, while the half-life time (T0.5) was 322 and 272 days, respectively. The afforestation of pastures with eucalyptus can potentially increase organic matter production in the system and benefit the other components of SSP.

RESUMO Estratégias que objetivam condicionar o solo impactam positivamente no sistema de produção de ruminantes a pasto. A produção de serapilheira é diretamente responsável por melhorias nas características químicas, físicas e biológicas no solo. Objetivou-se neste estudo quantificar e qualificar a deposição de serapilheira do Sistema Silvipastoril com Eucalipto (SSP), a fim de compará-lo com Floresta Estacional Semidecidual (FL) e Sistema de Pastagem em Monocultivo (MN), assim como a decomposição do material decíduo. Para isso, foram instalados 12 coletores de serapilheira em cada ecossistema, onde foi mensurado e estratificado a deposição do material decíduo a cada 28 dias, por 11 meses. A decomposição da serapilheira foi avaliada através do método de litterbags. A produção total de serapilheira dos meses avaliados para SSP, FL e MN foi de 10,74, 7,17 e 1,01 t ha-1, respectivamente. A constante de decomposição (k) para SSP e FL foi de 0,0021 e 0,0025 g g-1 dia-1, enquanto o tempo de meia vida (T0,5) foi de 322 e 272 dias, respectivamente. A arborização das pastagens com eucalipto tem potencial de aumentar a produção de matéria orgânica no sistema e beneficiar os demais componentes do SSP.

ABSTRACT The goal of our study was to evaluate the nutritional potential of dented corn hybrids for silage production. We performed a two-location trial in which 19 dented corn hybrids and five corn controls grew in four randomized blocks within two experimental areas located in the Northern (Campos dos Goytacazes) and Northwestern (Itaocara) Rio de Janeiro State, Brazil. We recorded yields of fresh and dry forage matter and yields of fresh and dry grain matter, as well as chemical composition variables. We interpreted variables by assuming a Normal distribution for yield variables and a Beta distribution for chemical composition and ratios. The SAS GLIMMIX procedure fitted the linear model under those assumptions. Dual-pool models fitted the gas production profiles generated by in vitro anaerobic fermentations. We used the nlme of R software to fit the dual-pool models and the information-theoretic approach to evaluate their quality of fit. We did a cluster analysis (NbClust of R) to group corn hybrids based on fresh and DM yields and kinetic parameters of in vitro gas production. Three clusters of corn hybrids stood out, their basic differences relied on fresh and DM yields. Nonetheless, the least-squares means for gas production characteristics among groups did not present disjoint confidence intervals. Therefore, we can infer that dented corn hybrids rank by forage yield, but not by forage quality, and recommend the most productive ones that consistently outstand in both locations (hybrids UENF-2203, UENF-2192, UENF-2193, and UENF-506-11).