Influência da adubação e do espaçamento na biomassa aérea da cultura de Pau-de-balsa (Ochroma pyramidale), no norte de Mato Grosso

Abstract

The planted forest sector is in Mato Grosso favorable outlook for its expansion, and favorable climate conditions for the rapid growth of different forest species, among which, the pau-de-raft is shown as an alternative to lamination and furniture industry. This study aimed to study the interaction between fertilization levels and spacing on growth in diameter and height and biomass of stands of trees homogenous pau-de-ferry in North Guarantã, MT. The plants were placed in the arrangement of sub-sub-divided plots 3 x 4 x 3 (three spacings x four levels of fertilization x Three Ages collection) in four randomized blocks, divided into three groups (plots), in which were distributed the spacings (2 x 2, 3 x 2 and 3 x 3 m). Within the tracks were randomized fertilization levels (sub-plots - 0, 0.5, 1 and 2 x reference dose). At 120, 260 and 375 days (sub-sub-plots) after planting were evaluated the total height (HT), trunk diameter at 10 and 130 cm from the ground (DAS and DAP), leaves, twigs, bark wood. Fertilization provided gains in height and volume with bark and volume without bark. The denser plantings produced higher amount of volume-ha, with lower volume individual trees. The cubed showed that the less dense planting, higher volume with and without bark presented by individuals with CAP same class. This difference is attenuated with increasing the CAP, but there is no difference in heights up to 375 days. The allometric equations were accurate and representative. There were greater gains in the production of biomass mainly in the trunk, as the increase in fertilization. The 3x3 spacing produced the largest volume of biomass in wood.