Micromorphometric and micromorphological investigations of a clay loam soil in viticulture under zero and conventional tillage

Porosity, pore size distribution and the orientation pattern of pores were measured on thin sections prepared from undisturbed soil samples by means of electro-optical image-analysis. Total porosity was significantly higher at all sampling times in conventionally tilled plots, but the proportion of pores ranging from 30 to 500 μm, which are considered the most important both in soil-water-plant relationships and in maintaining a good soil structure, was higher in no-tilled plots. Modifications of pore orientation pattern were also observed. Micromorphological observations revealed some differences between the two series of soil samples; the formation of surface soil crusts was strongly reduced in no-tilled plots.