Relations Between Soil Compaction And Plantation Growth Of A 8 Years-Old Lobolly Pine Second Rotation, In Misiones, Argentine.

Abstract

The provinces of Misiones and Corrientes, located in the northeast of Argentina, count with more than half of the area of Pinus plantations of the country, adding around 500.000 has. The species of more diffusion are Pinus taeda, and P. elliottii. The objective of the present work is to evaluate the impact of the traffic intensity of the clearcut in a Pinus taeda plantation over the growth and on the soil bulk density, at the age of eight years of the second Pine rotation. Height and dbh of the plantation were measured. The soil bulk density was sampled in three thickness, 0-10, 10-30 and 30-60 cm. The experience were composed by 84 plots installed in plantations located in Kandiudults soil types. Forty two of them located in areas of bigger traffic intensity and another point in areas of lower intensity. Also soil bulk density were sampled in virgin bordering. Significant differences were detected (P:0,05) either for soil bulk density and for total porosity for the thickness 10-30 cm, corresponding the biggest values of soil bulk density to the areas of bigger intensity. Regressions were identified statistically significant among dominant height and soil bulk density at 0-10 cm, 10-30 cm, total porosity at 0-30cm, and 0-60 cm. The values of soil bulk density detected under both conditions of traffic intensity were bigger than those corresponding to virgin soils; 20 to 25% bigger in the superficial thickness and of more than 10% in the 10-30 cm. It was concluded that the dominant height associated negatively with the bulk density of the thickness 0-10 and 10-30 cm, and therefore that the soil compaction affected the growth of the Pinus taeda, and that the compaction of both thickness was bigger in the areas with the biggest traffic intensity during the clearcut, and that impact remain after eight years.