Espaçamento entre faixas de árvores (Eucalyptus urophylla S.T.Blake) e suas interrelações com o acúmulo de forragem [Urochloa brizantha (Hochst. ex A. Rich.) Stapf cv. Xaraés], microclima e bem-estar animal

Abstract

The aim of this study was to evaluate the effects of three different spacing between trees ranges from a silvopastoral system in production and forage quality, microclimate and animal comfort. Was evaluated the production of Urochloa brizantha. Xaraés in two summers (2011 and 2012), and nutritional characteristics such as crude protein (PB), acid detergent fiber (FDA), neutral detergent fiber (FDN), lignin, cellulose and digestibility in vitro of organic matter (DIVMO) in the summer of 2012. Plants were grown in row spacings of 15m, 21m and 27m between alleys of Eucalyptus urophylla and in different lines of collection according to the distance from the trees. The experimental design was completely randomized factorial with five factors (3 spacing and 2 distances of collection). The microclimate and thermal comfort indices were evaluated at spacings of 15, 21 and 27m between trees tracks and in an area with full sun. To evaluate the microclimate data were collected on soil temperature (Tsolo), Global Solar Radiation (Rglobal) and photosynthetically active radiation (RFA). To evaluate the thermal comfort index were used temperature and humidity index (ITU), the globe temperature and humidity index (ITGU) and radiant thermal load (CTR). There was no interaction between dry matter yield and forage away from collecting in the various spacings. The dry matter production was lower in the spacing of 15m in two summers evaluated. The highest crude protein, lower FDN and DIVMO was in the smallest spacings and in areas under the canopy. The spacing of 21 meters proved to be the most suitable for the production of U. brizantha. Xaraés. The spacing of 15m showed most suitable values for soil temperature, however, showed the lowest values of RFA, which may compromise the development of plants. The best thermal comfort indices were found in the spacing of 15m. The presence of trees benefits the microclimate and thermal comfort of the environment favoring the production of both plants and livestock.