Image Analysis and Microscopic Techniques to Characterize Soil Pore System

Abstract

To evaluate the impact of management practices on the soil environment it is necessary to quantify the changes which occur in the soil struct re. Soil structure is one of the most important properties affecting crop production because it determines the depth that roots can explore, the amount of water that can be stored in the soil and the movement of air, water and soil fauna. Soil quality is strictly related to soil structure and much of the environmental damage to intensively-farmed land such as erosion, compaction and desertification originate from soil structure degradation. To quantify soil structural changes following agricultural activities, besides traditional measurements such as aggregate stability and hydraulic conductivity, pore space measurements are being increasingly used. In fact, it is the size, shape and continuity of pores that affect most of the important processes in soils (Ringrose-Voase and Bullock, 1984). Detailed insight into the complexity of the pore system in soils can be obtained by using mercury intrusion porosimetry to quantify pores with equivalent pore diameter 50 μm (macropores) to be quantified, which determine the type of soil structure (Pagliai et al., 1983b, Pagliai et al.1984).