Soil organic carbon and nitrogen characteristics in differently used grasslands at sites with drainage and without drainage

Extensive management (absence of management) of unfertilized permanent grasslands was examined for five years from the aspect of its influence on soil chemical properties of horizon A in a floodplain locality of the Crystalline Complex, in relation to water regime regulation, reclamations and liming. These treatments: without mowing (0), one cut (1) and two cuts (2) per year were used at sites without drainage (WD), with drainage (D) and with drainage water retardation (R). These average values were measured at all sites and for all treatments: content of soil organic carbon Corg 2.3-3.4%, combustible substances CS 12-15%, humic to fulvic acids ratio CHA/CFA 0.81-0.94, C/N 8-9, humification rate 0.6-0.7, exchange pH 3.9-5.1. All sites have deteriorated conditions for the activity of soil microorganisms (low pH). Determinations of the contents of organic carbon (Corg by thermal combustion, water soluble and hot water soluble carbon, CHA and CFA), CS and total nitrogen indicated decreases as a result of the influence of factors (drainage, liming, mowing) supporting mineralization and the cycle of soil organic matter. Mowing improved humus quality