With the objective to contribute at the establishment and development of sustainable production systems in the Llanos Orientales in Colombia, a project titled “Soil productivity losses due to water erosion in the Piedemonte Llanero in Colombia” was realized. In a 4% slope high terrace Oxisol of the Piedemonte Llanero (Tropeptic Haplorthox) 50 m² plots were established. Mean soil loss values after three study years were 2.3, 19.7 and 96.4 t ha^-1 yr^-1, for pastures (Brachiaria Decumbens), crop rotation (rice, mays and soja) and bare soil plots, respectively. A natural degradation for a light reduction in organic matter content and pH soil process was observed. The eroded nutrient enrichment ratio for P, Ca, Mg, K, Na and organic matter (5.1, 2.83, 2.57, 2.08, 1.41, 0.99)were higher in pastures followed for crop rotation plots. Soil density was temporary and spatially homogeneous with values between 2.55 and 2.56 g cm^-3. Infiltration rates were between moderately rapid and rapid categories. Hydraulic conductivity decreased along study time in bare soil plots (7.63 to 5.31 cm hr^-1), and increased in pastures (13.16 to 17.99 cm hr^-1)and crop rotation plots (9.07 to 13.78 cm hr^-1). These soils had a low probability to crust due to clay and silt textural fractions (15 - 25%). Maintenance of bare soil during study time produced high reductions in majority of soil microorganisms, except mushroom (1.94*10⁴UFC). Soils with rice-soja rotation reduced bacterias (0.69*10⁸ UFC) and soil mesoorganisms (4.67 mesoorg m^-2) presence. An acceptable biological activity was determined in pastures system, whereas in bare soil it was very low due to physical and chemical soil propierties of Oxisols.