Land use influence on micro-aggregates

Abstract

There were assessed differences in micro-aggregate composition depending on soil organic matter and soil texture in different ecosystems (forest, meadow and urban ecosystems and in agro-ecosystems on various plots) on Eutric Fluvisols and Haplic Chernozems. Micro-aggregate formation is influenced mainly by soil texture, but in agro-ecosystems, the quantity and quality of soil organic matter play an important role. The content of total organic carbon and its labile fraction positively influence creation of micro-aggregates larger than 0.01 mm.
In relation to the quality of soil organic matter, creation of micro-aggregates is influenced mainly by the stabilised humus substances. In this research, the effect of humic acids was positive in case of smaller aggregates, but in case of their bound with the larger fraction of 0.25 mm their degradation occurred, thus the soil organic matter was less stabilised. Conversely, content of fulvic acids was mostly in negative correlation with the individual micro-aggregate fractions, but in case of micro-aggregates to 0.001 mm it was the positive correlation, because with increasing formation of aggressive humus substances, clay content is increasing, as well. Soil organic matter plays an important role especially in the creation of larger aggregates.