Monitoring of paricá plants in an area of forest restoration

Abstract

Current study evaluates the vegetal development of Schizolobium parahyba var. amazonicum (Huber x Ducke) Barneby), commonly known as paricá, in pasturelands in the process of restoration in the Mosaic of Conservations Units of Carajás PA Brazil. The area comprises the connectivity program of forest fragments. They are degraded areas, previously occupied by pastures, which are at present being recuperated with native forest. Evaluation of the development of parica plants comprised plant height, diameter at breast height, cubing and canopy projection. Experimental data underwent regression analysis and Pearson´s co-relation. As from strict cubing by Smalian method, a mean factor equal to 0.55 and a strong positive co-relationship with diameters and heights (r=0.83 and r=0.86) were determined. Cubing data helped in the adjustment of a mathematical model of double entry (diameter at breast height and height as independent variables) for estimating form factor in which regression adjustment statistics resulted in relatively high rates for the coefficient of determination (R2 = 0.78) and low rates for standard estimation error (Syx = 0.05). By applying the Schumacher-Hall´s logarithm method for volume estimates, good statistical adjustments were obtained with a high coefficient of determination (R2 = 0.99), low standard estimate error (Syx = 0.07) and residual dispersion without biases.