Metodos de determinação do selamento superficial na irrigação por aspersão

AUTOR(ES)
DATA DE PUBLICAÇÃO

1997

RESUMO

Soil surface sealing is characterized as an organized fine particle layer with high density which can reduce the soil infiltration rate. It is caused by the impact of rainfall or irrigation water droplets. The occurrence of the soil surface sealing can result in negative effects, such as, reduction of soil water intake and soil-water holding capacity, inercasing of runoff volume associated with erosion risks, rcduction in seed germination and less soil-atmospherc gaseous exchange. These effects can promote a loss of production and yield reductions. Sometime the plant germination inhibition is so high that can limitcd the soil cultivation. The objective of this research was to evaluate five ditrerent methods to determine the occurrence of the soil surface sealing causcd by sprinkler irrigation water applications. It was used in this work a Dark-Red Podzolic soil from the Mococa region, state of Sao Paulo. The following methods were evaluatcd: seed germination percentage, soil penetration resistance, particles detachment, density determinations through gamma-rays attenuation and computerized tomography. The occurrence of the surface scaling were analyzcd in soil samples placcd in three different distances from the sprinkler. The density determination methods showcd to be suitable to characterize the surface sealing occurrence, but its resolution levei have to be improved. Thc other evaluated methods (seed germination, soil penetration resistance and particles detachment) were not able to direct quantify the surface scaling process but allowcd to quantify its effects. Ali five uscd methodologics found the soil surface scaling occurrence more pronounced with increasing distance from the sprinkler nozzle duc to the increasing of droplets diameters along the jet trajectory

ASSUNTO(S)

irrigação por aspersores solos engenharia de irrigação impacto ambiental

ACESSO AO ARTIGO

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