Effect of surface-applied millet stalk mulch on soil bulk density and total porosity

الملخص EN

A field experiment was conducted at the University of Zalingei Research Site, Zalingei, Western Darfur state, Sudan, on sandy clay loam soil, using factorial design.

The effects of five water harvesting techniques including surface mulching and land slopes (0.97%, 1.36% and 1.76%) on some soil physical properties were investigated.

Bulk density and total porosity of the soil were measured at three periods (before sowing the crop, at mid-season and after harvest) and at four depths (0-15, 15-30, 30-60 and 60-90cm) during the 1997/98 and 1998/99 growing seasons.

The results revealed that, the slope gradient had no significant effect on both bulk density and porosity values, whereas, the effects of measurement period and soil depth were highly significant (P≤0.01).

The mean bulk density values increased with increasing soil depth at all slopes and measurement period were decreased in the middle of both growing seasons then increased after crop harvest, but they were still lower than those before treatment application.

The porosity showed a reverse trend to the bulk density.

The upper 30cm layer of the soil was significantly affected by the applied techniques, especially the surface straw mulching.

On the other hand, the effects of water harvesting techniques on the bulk density and porosity were not significant at the 60-90cm layer of the soil.