Resumo

NUNEZ RAVELO, Franklin. Effects of microbiotic crust on soil properties, South of the "Los Barrancos" creek, Quíbor Valley, Venezuela. Invest. Geog [online]. 2014, n.84, pp.5-19. ISSN 2448-7279.  https://doi.org/10.14350/rig.33959.

On the floor of Quíbor, grows discontinuously a crust formed by lichens, bryophytes and cyanobacteria. The purpose of this research is to identify variations in the behaviours of some soil properties by comparing soil samples with and without crust. This is a field research developed in three phases: The first, called field, in order to collect samples of soil, with support in the random digits table and from two longitudinal transects, they are used on every ten meters a quadrat square 25 x 25 cm; the second phase, laboratory, in which soil properties determined: a) physical as % moisture; b) chemicals such as salinity, pH, Electrical Conductivity (EC) and organic carbon (OC); and c) biochemical, including organic matter (OM) and carbon dioxide (CO₂) given off; the third phase, statistical analysis, "t" test was used in order to identify significant changes between the two sample groups. We conclude that the presence of the crust on the soil surface increases metabolic activity, the OC and OM. As for pH, EC, salinity and% H there were no significant changes.

Palavras-chave : Soil properties; microbiotic crust; soil moisture; pH; salinity; organic carbon in the soil; organic matter.