Biomass survey of fine roots and constituents of organic matter in different areas in the municipality of Paragominas-PA.

Abstract

The objective of this work was to quantify fine root biomass (≤ 5.0 mm) in eucalyptus, pasture
and secondary forest area. Fine roots are the main responsible for the absorption of water and
nutrients, constitute less than 1% of the total biomass of the forests, but their annual production
can contribute with more than 50% in the total net primary production of the forests. The
experimental design was a double 3x3 factorial design was used where three areas (Lawn,
secondary and eucalyptus forest plantations) and three depths of soil (0-10 cm, 10-20 cm, 20-
30 cm). A transect of 25 m was established in each area. The collection was done in points
of 5 in 5 m. Then trenches 30 cm deep were made. The biomass of fine roots is larger in the
secondary forest and the amount of humic acid in the site is directly linked.