Recomposiçao vegetal com espécies florestais e forrageiras em áreas de empréstimo da Hidrelétrica Governador Parigot de Souza

Abstract

The purpose of the present research was to analyse the behaviour of eigth forest species, namely, acácia negra (Acacia mearmsii Willd), acacia trinervis (Acácia longifolia (Andr.) Wildenow), angico (Parapiptadenia rigida (Bentham ) Brenan), bracatinga (Mimosa scabrella Bentham), canafístula (Peltophorum dubium (Sprengel) Taubert), Eucaliptus globulus (Eucalyptus giobulus Labill), Eucaliptus viminalis (Eucalyptus viminalis Labill) and monjoleiro (Acacia potyphylla D. C.), as well as three herbage species, namely, capim chorão (Eragrostis curvalis Ness), capim gordura (Melines minutiflora P. de Beauv) and soja perene (Glycine wighttii (R. Granh ex. Wight and Arn.). Verde, for the recovery of the "borrowarea” of the Governador Parigot de Souza Hydroplant dam, where the soil had been deprived of A and B zero horizons. The statistical design was a "split plot in random blocks" with three repetitions; the forest species were planted in the subunits and the herbage species in the whole units. The percentage of soil occupation by the latter was whole units. Averages were compared through the SNK test with a 95% probability. The development of the variables -heigth, root collar diameter and survival -were the parameters used for the selection of the more promising forest species. Five measurements were taken, from the fourth up to the twentieth month after plantation. Finally, six regression equations were tested, in order to predict the heigth of the forest species considered viable in the experiment. From the eigth forest species tested, five were considered viable during the period under examination: acacia negra (Acacia mearsii Willd), acacia trinervis (Acacia longifolia (Andr.) Wildenow), Eucaliptus globulus (EucatyptulJ g"£.2.. butu~ Labill), Eucaliptus viminalis (Eucatyptus viminalis Labill) and bracatinga (Mimosas scabrella Bentham). In the whole units, capim gordura (Melinis minutiflora P. de Beauv.), capim chorão (Eragrostis curvula Ness) as well as the mixture of the three species were considered viable for protecting the soil. The linear regression equation was the most appropriated for predicting the heigth of the five selected species.