The Soil Structure Changes under Varying Compost Dosage

The influence of different application of grape marc compost on the soil structure and the water stability of soil aggregate were studied in the course of four-year experiment. The trial was carried out in a Velké Bílovice vineyard in the Czech Republic. The altitude of the locality is about 200 m above sea level, the long-term average annual precipitation is 550 mm, the long-term average annual temperature is 9.5°C. The soil is Haplic Chernozem, loamy textured. Three variants were established: Variant 1 - control, no compost, Variant 2-30 t of compost per ha, Variant 3-60 t of compost per ha. The compost from pomace, poultry droppings, mown grass and straw was made in an EWA aerobic fermentor in an intensive and controlled process in an enclosed space and shallow ploughed (0-0.15 m) into the soil every year after harvest. The results of the experiment were statistically processed by multifactorial analysis of variance and then by Tukey’s test of simple contrasts. The highest values of structural coefficient and water stability of soil aggregate were found in the variant with the highest dosage of compost. It was found that the application of grape pomace compost to the soil had a positive effect both on the soil structure and the water stability of soil aggregates.