Variation of bulk density in soil orders of Costa Rica

Abstract

Data from 111 profiles described by various authors was used to characterize bulk density in the following soil orders found in Costa Rica: Inceptisols (38.6% of the total soil resources), Ultisols (21%), Andisols (14.4%), Entisols (12.4%), Alfisols (9.6%), and Vertisols (1.6%). The range of variation for soils studied is 0.53 to 2.00 Mg m-3, which is high. The values of bulk density tend to increase with depth due to its lowering by greater biological activity in the A horizon. If there are no compacted layers, a significant increase is found when illuviated clay accumulates in the argillic horizon in Alfisols and Ultisols. Values of bulk density are related to the origin of parent material in Andisols and clay mineralogy in Vertisols.