ABSTRACT
Nitrogen plays a leading role in the formation and functioning of whichever terrestrial ecosystem. From the nitrogen status of soil cover depends on area’s potential productivity, functioning activity and therefore its suitability for crops and land use. As a result, long-lasting agricultural activity for the agricultural areas in Estonia has been taken the best as possible soils of the region. In the Northern part of Estonia, the best soils on agricultural landscapes are typically leached and eluviated soils (Cambisols, Luvisols), but in the Southern part – pseudopodzolic and ameliorated sod-podzolic soils (Retisols, Podzols). In all territories, these soils are accompanied in more or less extent by the drained gley-soils and peat soils (Gleysols, Histosols), which are bordered by transitional peaty (histic) soils. For essential diversifiers of agricultural landscapes are distributed on sites with specific pedo-ecological conditions erosion-affected, alluvial and coastal soils.
The main attention in the work is paid to the dominating soil species’ (as an essential taxon in Estonian Soil Classification) total nitrogen concentration (g kg-1) and superficial density (Mg ha-1) and to the ratio C:N. These parameters are analyzed by the dominating arable and grasslands’ soil species in different levels of their profiles integration as (1) humipedon, (2) soil cover or solum and (3) metric layer of soil. Therefore, the research embraces besides humipedon as well the subsoil and the parent material or substrate of the soil cover. As a main outcome of the work, the generalized nitrogen status indices of the dominated agriculturally used soil types are given on the background of normally and abnormally developed soil matrixes.
