SIMEONOVA, N. Agricultural University, Bulgaria , TODOROVA, S. Agricultural University, Bulgaria

Humus content and humus fractions after long-term systemic mineral and organic-mineral fertilization on mollic fluvisols

33761

The present work studies the effect of long-term systemic mineral and organic-mineral fertilization on the humus amount, humus type and humus fractions on Mollic fluvisols in Plovdiv region. Fertilizer norms are 1) N75P30K20; 2) N25P15K0 + organic; 3) N50P0K20 and 4) Standard. It was found that long-term systemic mineral and organic-mineral fertilization (forty-seven years) has a stabilized effect on humus content in studied soils. The systemic fertilization lead to a slight decrease of soil humus amount, although the fertilization was excluded since three years. The humus type – was not influenced from the long-term fertilization.

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Humus , Humic acids , Fulvic acids , Humus type , Fertilization

Anadolu Journal Of Agricultural Sciences

147