RESEARCHES REGARDING THE SOIL LOSSES PRODUCED BY EROSION IN THE NORTH WESTERN ROMANIA PUBLISHEDRadu Brejea
The paper is based on the researches carried out during 2007-2009 in the special plots placed on the hill with 10 % slope in Agricultural Research and Development Station Oradea. The metal panels and soil dams there were between the plots. The variants studied: black fallow, pasture, wheat, maize on the level curves, and maize from hall to valley. The biggest soil losses were determined in the variant with black follow and the variants with maize seeded from hill to valley maize on the level curves, wheat and pasture had the smaller losses in this order. The biggest yield losses were determined in the year with the biggest annual rainfall, 2007. The maize crop from hill to valley determined soil losses bigger than the yield losses from variant with maize cropped on the level cures. The wheat assured a better protection against the erosion in comparison with the maize and the best protection against erosion was assured by the pasture. In the same time the erosion determined the differences between the physical parameters (hydro stability of the macrostructure – aggregates bigger than 0.25 mm, bulk density, g/cm3; total porosity, %; hydraulic conductivity, mm/h; penetration resistance, kg/cm3) of the soil in the top and the base of the hill; in the top of the hill the values of the physical parameters were less favorable for plants in comparison with the hill base. The worst situation was registered in the variant with black fallow fallowing the variants cropped with maize from hill to valley, the variants cropped with maize on the level curves with and pasture. The big soil and the big yield losses determined in the variant with maize on the level curves the big soil losses determined in the variant with black fallow are the arguments to crop the wheat (or other plants with small distance between the rows) or the pasture on the hill with 10% slope in the conditions of the area with 615.2 mm rainfall a multiannual average too. The results were obtained in the project “Study of the risk factors, the quantification of their impact on agricultural systems, the creation of the new genotypes and technologic needed for sustainable development”. CEEX 35/2006 project.
hill; erosion; clean fallow; pasture