Abstract

KOWALJOW, Esteban  and  ROSTAGNO, César Mario. Gas-pipeline installation effects on superficial soil properties and vegetation cover in Northeastern Chubut. Cienc. suelo [online]. 2008, vol.26, n.1, pp.51-62. ISSN 1850-2067.

In this work we describe the impact of a gas-pipeline installation and the replacing of the material removed in part of the clear-cutting, on some physical and chemical properties of the soils and vegetation in three ecological sites of Northeastern Chubut. In these sites we identified four different areas: area 1, clear-cut strip, where the traffic of heavy machinery was intense; area 2, clear-cut strip, with soil and vegetation replaced; and other two areas in the undisturbed adjacent steppe: mounds associated to shrubs and mound interspaces. The highest bulk densities were recorded in area 1 and in the mound interspaces (1.43 Mg m^-3). The penetrometer resistance was significantly higher in the areas 1 and 2, recording values higher than 1 MPa. The infiltration rate was much higher in the mound (261 mm h^-1) than in the other areas. The infiltration rate of area 2 (85 mm h^-1) was higher than that of area 1 (35 mm h^-1) and the mound interspaces (50 mm h^-1). Total nitrogen and organic carbon content in soils of the areas 1 and 2 were similar to those of the mound interspaces and significantly lower than those of the mound, except in the area 2 of one ecological site. Clear-cut and topsoil removal, and the subsequent traffic of heavy machinery caused by underground gas-pipeline installation produced a strong impact on the physical properties of these soils. The main limitation in the highly disturbed soils was the decrease in the infiltration rate, mainly due to high compaction and low porosity. This may in part explain the slow vegetation cover recovery in the area 1. The replacement of the stripped sediment and vegetation on the disturbed strip did not improve the recovery of the vegetation cover. It was mainly due to the low quality of the sediments extracted from the pipeline ditch.

Keywords : Clear-cutting; Traffic; Compaction; Infiltration Rate; Soil Physical and Chemical Properties; Arid Lands.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )