WATER-AIR PROPERTIES OF MUCK-LIKE SOILS

摘要

The paper presents research results concerning water retention curves, pore size distribution, and redox potential in profiles of muck-like soils under varied agricultural use. It was found that relatively favourable conditions for plant growth and development occur only in the surface horizons of muck-like soils, where the amount of water easily available for plants is at the level of 10-15%. Tillage of muck-like soils as arable fields for crop plants with low requirements, such as oat, potato, or field vegetable crops (cabbage) results in an almost two-fold decrease, in their muck-like horizons, of the content of large pores from 34 to 19% by vol., and an increase in the content of medium pores from 10 to 14-15% by vol., as compared to multi-yearmeadow cultivation. The studied soil profiles, with pore size distribution favourable for the processes of drying, are characterised by a strong resistance to reduction, i.e. redox potential values above +400 mV, observed within a broad range of soil water potential values, and which mean that one should not expect nitrate reduction in the soil profiles studied, and consequently no generation and emission of nitrous oxide (N_2O) to the atmosphere. The muck-like soil profiles studied can also be classified among soils with weak emission of carbon dioxide, which means that the soils do not contribute to the process of atmospheric/climatic warming.