Effects of soil erosion by water under different tillage treatments on distribution of soil chemical parameters

Abstract

Soil losses by water erosion were studied under six different tillage treatments, which differ in depth and direction of tillage and planting during a twenty-year period (1995–2014) on Stagnosols in central lowland Croatia. Studied tillage treatments were: control plot (bare fallow-BF), ploughing up and down the slope to 30 cm (PUDS), no-tillage (NT), ploughing across the slope to 30 cm (PAS), very deep ploughing across the slope to 50 cm (VDPAS), and subsoiling to 50 cm + ploughing to 30 cm across the slope (SSPAS). The paper presents the following chemical parameters: soil pH, soil organic matter (OM), plant available phosphorus (P-P<sub>2</sub>O<sub>5</sub>), plant available potassium (K-K<sub>2</sub>O), total carbon content (C<sub>tot</sub>), total nitrogen content (N<sub>tot</sub>) and CN ratio of non-eroded soil and soil loss from studied treatments. All soil sediments had significantly higher content of the studied parameters compared to non-eroded soil. The overall respective levels of OM, C<sub>tot</sub>, N<sub>tot</sub>, P-P<sub>2</sub>O<sub>5</sub> and K-K<sub>2</sub>O loss by eroded soil were as follows: 0.86 (NT) − 10.86 (BF) t/ha, 0.10 (SSPAS) – 2.60 (BF) t/ha, 0.015 (SSPAS) – 0.392 (BF) t/ha, 0.012 (NT) − 0.173 (BF) t/ha and 0.017 (SSPAS) − 0.158 (BF) t/ha. No-tillage and treatments with tillage across the slope (PAS, VDPAS, SSPAS) proved to be much more efficient in storing investigated soil nutrients.