Humification of organic matter in calcareous soils from Malta

Abstract

Organic matter is that fraction of the soil that consists of substances that used to be part of living organism such as plant and animal remains, and is found in various stages of decomposition. Humification is a biological and chemical process which involves the transformation of end products of organic matter degradation into complex molecules that are referred to as humus. Degradation of freshly added organic residues in soil is carried out by micro-organisms such as bacteria, fungi and other higher fauna, earthworms and ants and micro-organisms. The objective of this study was to evaluate the quantity of organic matter and humic acids and fulvic acids ratio in a selection of soils from Malta. Samples were taken from two different soil depths, and soil selection included different soil types and soil use. The highest level of OM was found in a Silt Loam soil and the lowest level in a Sandy Soils OM content in the sandy soil studied was relatively much lower than OM content in the other soils. There was no significant difference in the HA/FA Ratio between the soil types.