Dependence of soil fertility on organic and mineral fertilization in a 46-year long-term field experiment

Abstract

Increasing doses of farmyard manure (FYM) or equivalent mineral NPK fertilizers and their combinations were analysed in a crop rotation with potato, maize and winter wheat with special regard to their long-term influence on soil fertility. The yield-increasing capacity of FYM doses was only 82%, as compared to the equivalent amount of mineral NPK. Fairly high N release (50.9 kg ha −1 ) could be observed on the unfertilized plots. Great differences in N utilization were recorded, depending on the form and dose of fertilizers. The average N utilization from FYM was only 29.3%, while that of the equivalent fertilizer application was 49.8%. The lowest soil reactions were observed without fertilization and at the highest NPK doses. Negative N balances generally resulted in low soil organic matter content. FYM and equivalent NPK fertilizers had a similar influence on the ammonium lactate (AL)-extractable K 2 O content of the soil, while an increase in the AL-P 2 O 5 content could be observed in the case of mineral fertilization.

Proceedings of the 10th Alps-Adria Scientific Workshop, 14–19 March 2011, Opatija, Croatia – SOIL

“…Soil texture is a sandy loam with low organic matter and P content and medium K content, pH (KCl) = 7.1. For more information see Hoffmann et al (2010). Legends: 1 FYM= 35 t ha -1 farmyard manure in 5 years, distributed in the first and third year 1 eqvNPK = mineral NPK equivalent to 35 t ha -1 FYM in 5 years, (N: yearly, P and K in the first and the third year distributed) Straw= the actual maize or wheat straw yield, ploughed down in fall.…”