Correlations between several chemical parameters of soil and earthworms' density depending on plant culture and organic-mineral fertilization.

Researches have been carried out on the land of Didactic Station of UASVMB Timisoara, on a cambic chernozem, low gleyed. Identification of the pedological conditions and the morphological description of soil profile, as well as soil identification by type, respectively by subtype, have been made according to Romanian System of Soil Taxonomy (SRTS, 2003). Soil sampling was made by genetic horizons in natural arrangement and disturbed arrangement. Two types of organic- mineral fertilizers with granules coated with humic-potassic acids have been tested, noted L- 200-HUM and SH-120. The researches have been carried out in two plan cultures, maize (Zea mays L.) and sun-flower (Helianthus annuus L.). On the soil of these crops the organic-mineral fertilizers have been applied in dose of 83 kg active substance (N)/ha. Earthworms' extraction from soil has been