ABSTRACT
The present work aimed to study the volume growth of a Pinus elliottii Engelm stand in Ponte Alta do Norte , Santa Catarina. This plantation has been submitted to three thinning levels according to the basal area of the non-thinning control parcel. In order to achieve this goal, the maximum, optimum and critical basal areas have been studied as well as the hypsometric relationship and the development of the volume increments - annual current, annual mean and the periodic ones. As results, it has been obtained the determination of the critical stocking degree in different periods of stand development. They are 0.76 for a 7.5-10.5 year-old period; 0.80 for a 10.5-13.5 year-old period; 0.87 for a 13.5-16.5 year-old period; 0.90 for a 16.5-19.5 year-old period; 0.91 for a 19.5-25.5 year-old period, and 0.87 for the throughout period of the study ( 7.5 through 25.5 year-old). The output loss in T1 treatment (thinning on 25% in the control basal area) has been 9%; in T2 treatment (thinning on 50% in the control basal area) has been 20% and in T3 treatment (thinning on 75% in the control basal area) has been 54%.
Key words:
basal area; thinning; growth