Analysis of nebkhas on vegetation-fixed draas in the arid central-south region of Argentina

PASTRÁN, G.; EDUARDO MARTÍNEZ CARRETERO

JOURNAL OF ARID ENVIRONMENTS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2011

0140-1963

Nebkhas, developed by the trapping of sand within the body of a plant, were studied in the Médanos Grandes system, arid central Argentina, during the spring of 2009. In this system, formed by megadunes and overlapping dunes, nebkhas dynamism was analyzed considering their location on windward and lee slopes. In each nebkha, sand movement was studied through erosion pins and considering E, W, N and S orientation. Predominant winds blow from the south-southeast; however, no significant statistical differences were found in the erosion-deposition process, between windward and lee slopes or orientations. Nebkhas on the lee show slow growth and those on windward slope moderate deterioration. Tricomaria usillo is the dominant plant species in the nebkha formation process. All studied nebkhas were homogenous in the morphometry with their largest diameters being 4.71±1.5 m and 4.25±1.3 m, in windward and lee slope respectively. In addition, the constant rate of growth in height was estimated as being 0.02 cm/year and 0.04 cm/year, for windward and lee slope