Evaluating the efficiency of different systems of conservation in three horticultural crops during two cycles and other permanent covers

A field trial using 10 m by 2 m erosion plots was conducted at the Bajo Seco Experimental Station, to evaluate the effectiveness of management and conservation practices associated with soil and water losses, in three horticultural crops (carrot, beat and leek), simultaneously planted during two growing periods per year. A bare plot was kept and the crops were planted in three series of three plots each, according to the conservation systems: "platabandas" (shallow furrows 1 m apart transverse to the slope) + hedge using Vetiveria zizanoides; without conservation practices (flat land); and "platabandas" only. Permanent covers were also evaluated using erosion plots: taiwan grass, natural forest, greggii pine and peach, the last one with and without hedge. The total rainfall was 526.7 mm, yielding an erosivity index (R) of 2613.9 Mjxmm/haxh; soil erodibility (K) was 0.018 Mgxhaxh/MjxDmmxha. It was found that the "platabanda" + hedge system, with soil losses between 0 and 0.3 Mg/ha, was the most efficient in reducing soil and water losses, followed by "platabanda" only, with soil losses between 6 and 20 Mg/ha, and the system without conservation practices with the highest soil losses. The last two systems were not considered sufficiently enough in reducing soil losses. Leek was the less protective crop, with soil losses between 20 and 64.3 Mg/ha for "platabanda" and without conservation practices. Permanent covers, on the other hand, with soil losses below 0.1 Mg/ha, were highly efficient in reducing soil losses.