Compressibility of soils in a long term field experiment with intensive deep ripping in Romania

• Published in: Soil & tillage research Vol. 56; no. 3; pp. 185 - 196
• Main Authors: Canarache, A, Horn, R, Colibas, I
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-08-2000; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Compression index; Cropping systems. Cultivation. Soil tillage; Deep ripping; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Precompression stress; Soil tillage; Stagnic Luvisol; Tillage. Tending. Growth control; Balkan Peninsula; Europe; Romania; Compression index; Precompression stress; Deep ripping; Stagnic Luvisol; Cultural practice; Soil tillage; Compressibility; Luvisols; Long term test; SOIL TEXTURE; Property of soil; Laboratory test; Subsoiling; Compaction; Compression test; Field experiment
• ISSN: 0167-1987; 1879-3444
• DOI: 10.1016/S0167-1987(00)00143-4

Laboratory compressibility tests were done on soil samples taken from a field experiment 21 years old, located on a Stagnic Luvisol, with deep ripping performed with various frequencies: no ripping, ripping every 8, 4 and 2 years, and ripping yearly. Precompression stress was found to increase with depth of the soil profile down to some 60
cm, and somewhat decreasing at the depth of 70–75
cm, which corresponds to the Bt horizon. Due to ripping, the values of the precompression stress decreased; for soils from experimental treatments with different periodicity of ripping operations, the differences were small, and not in a very definite direction. The estimation procedures suggested by Lebert to predict precompression stress for “normal” arable soils could not be applied to ameliorated soil samples investigated in this paper because repeated ripping prevents a continuous aggregate formation and results mainly in structural texture dependent relations. The compression index showed an increase down to 60
cm and a decrease in the Bt horizon (70–75
cm). In the different experimental treatments, it showed a less clear variation, although some trend of increasing with increased number of rippings may be considered. As inferred from these parameters, soil strength and compressibility do not affect directly crop yields.