SOIL RESISTANCE AND BULK DENSITY UNDER DIFFERENT TILLAGE SYSTEM

Abstract

A stationary field experiment of a reduced soil tillage was implemented at a Hypogley (Hypogleyic soils A–Gso–Gr soil horizon sequence) soil type of Eastern Croatia during three seasons and set up as a split-plot randomized block design in four repetitions. The tillage systems (TS) were as follows: 1) conventional tillage, i.e., plowing at 30 cm (CT), 2) disking up 10-12 cm (DT), 3) soil loosening up to 35 cm (LT), 4) no-tillage (NT). The experiment was designed to compare the penetration resistance (PR), soil moisture (SM), and bulk density (BD) at different TSs and soil depths. A cone penetrometer was used to measure the PR with 10 prods per TS, accompanied with a measurement of SM with a soil auger on every 10 cm, with four samples up to a 40-cm depth. The BD was determined by metal cylinders on every 10 cm up to a 30-cm depth, being weighed and dried thereafter to obtain an absolutely dry sample, and then calculated using absolutely a dry soil sample mass (m_s) and the soil volume (V). The PR and SM were significantly influenced by the TS and soil depth. The CT had the significantly lowest PR at all depths, while the DT has manifested a significantly higher PR at a soil depth amounting to 10 to 20 cm. The PR on NT were significantly diverse from the CT at all soil depths. The BD varied significantly concerning the TS and the soil depth. Subsequent to the three years, the CT had a significantly smaller BD at a depth amounting from 0 to 10 cm, and a significantly higher BD at 20- to 30-cm depth, compared to reduce the TS.

Keywords

• soil compaction
• bulk density
• soil moisture
• tillage systems
• soil depth