Agricultural soil properties and crop production on Lithuanian sandy and loamy Cambisols after the application of calcareous sapropel fertilizer

Abstract

Lake-derived organic-rich mud (sapropel) is used as a soil fertilizer on sandy loam Haplic Luvisols in Lithuania. Various application rates (50, 100, 150 and 200 t ha-1) were applied to crop rotations (maize, barley, clover, winter rye, potatoes and oats) and their subsequent long-term influences on soil physico-chemical properties and crop production determined. Soil agrochemical properties were evaluated before (1984 – 1985) and after the end of the first (1989 – 1990), second (1995 – 1996) and third (2001 – 2002) crop rotations from seven treatments with four replications. In most cases, after each crop rotation, there were notable increases in pH, total absorbed bases, total nitrogen content, available phosphorus and potassium and soil organic matter content (humus). After three rotations, changes in soil acidity, total nitrogen and humus on all sapropel treatments were significant (p < 0.05), but effects on phosphorus and potassium were not significant. In comparison, for most treatments, manure produced greater improvements in soil properties than sapropel. However, after 18 years of application, sapropel did improve crop productivity almost to the level achieved by applications of manure and fertilizers. Therefore, results demonstrate there are long-term benefits of sapropel applications, namely improvements in soil properties and crop productivity.