Rähkmuldade seisund ja levik Eesti põllumajandus- ning metsamaastikes

In the overview nomenclature, properties, distribution, productivity and usage of ryhky soils, as the Year 2021 Soil of Estonia, are treated. As synonyms of the name ryhky soils, also the names pebble rendzina and gravelly soils have been used in Estonian Soil Classification (ESC). In overview, the main attention is paid to dry, fresh and moist rich in coarse calcareous material mild-humuous (mull-type) soils. After WRB these soils may be characterized by prefix qualifiers as calcaric or eutric, skeletic or hyperskeletic and rendzic or mollic CAMBISOLS, LITHOSOLS or REGOSOLS, whereas all of them have endogleyic versions as well. The wet and eroded ryhky soils have been excluded from the overview as their properties depend not so on the coarse calcareous earth content as on feeding their soil water or water erosion. The area of ryhky soils forms 6.3% from whole Estonian soil cover and 11.1% from the arable land. The main criteria of ryhky soil species' determination are calcareousness, content and shape of coarse soil fragments, and water regime of soil cover. By ESC six soil species have been determined, from which three ones have endogleyic character. The fine earth texture of ryhky soils is mainly loam. From the coarse fractions, the indicative role belongs to the small stones (ryhk, pebble and shingle). The morphology, humus status and suitability of ryhky soils for management are treated on the level of soil species independence of land use (arable, forest or grassland).