Balanço de serapilheira em plantios de Eucalyptus clone H-13 no médio Norte de Mato Grosso

Abstract

The state of Mato Grosso has presented in the last years, a growth in the planted forests areas, highlighting the eucalyptus gender, because of the diversity of products and benefits brought to the forest habitat through the litter deposition. However, little is known about the deposition dynamics in the climatic conditions of our region. The purpose of this study was to evaluate the litter balance of Eucalyptus urograndis (Clone H13) in different ages and environment interfaces. It was selected areas with three, five, seven and nine years old, with the evaluations occurred in central areas of the field. On five and seven years old areas, also was evaluate the interfaces (borders) eucalyptus/crop and eucalyptus/native forest and, remaining native forest areas. Collectors made by shading screens poliefinas of 50%, in the dimensions of 1,0 x 1,0 m and 0,50 m above the ground were installed, being the collections of the deposited material realized monthly. For quantification of the decomposition rates, it was use 50g of dry material added in litterbags, being the collections realized at 30, 60, 120, 180, 240 and 300 days after the distribution (DAD), using the simple negative exponential models to obtain the decomposition rate. It was observed in the driest months of the year higher rates of litterfall, with emphasis on the leaf, main forming fraction; in the rainy season, it was observed the highest decomposition rates. It was detected that higher percentages of shaded area increase litterfall rates and the relative humidity inside the field, because of the lower insolation, carrying higher decomposition rates.