Effect of composted olive cake on soil physical properties

Large areas in Jordan are planted with olive trees, resulting in the production of large amounts of olive cake (OC) and annually imposing a disposal and pollution burden. This research examined the use of OC compost as a soil amendment and its effect on soil physical properties such as soil water retention and infiltration in terms of depth of penetration and accumulated intake on two soil types: clay (S1) and silt loam (S2). Composting was intended to reduce the harmful effects of untreated OC. Olive cake was added to soil at three levels: 2%, 4%, and 8% by weight. Compared with control (untreated soil), adding composted OC caused significant improvements in soil physical properties considered. The changes in soil properties were, in general, proportional to the levels of compost added. For S2 at the 8% level, the depth of penetration and accumulated intake of water in soil were increased by 36.5% and 34.3%, respectively. For SI, the corresponding increases in the depth of penetration and accumulated intake were 27.1% and 35%, respectively. Furthermore the increase in soil water-holding capacity for S2 and S1 at the 8% level of compost addition was up to 10.3% and 16.5%, respectively.