Compared performance of penetrometers and effect of soil water content on penetration resistance measurements

Abstract

Modern agriculture techniques have a great impact on crops and soil quality, especially by the increased machinery traffic and weight. Several devices have been developed for determining soil properties in the field, aimed at managing compacted areas. Penetrometry is a widely used technique; however, there are several types of penetrometers, which have different action modes that can affect the soil resistance measurement. The objective of this study was to compare the functionality of two penetrometry methods (manual and automated mode) in the field identification of compacted, highly mechanized sugarcane areas, considering the influence of soil water volumetric content (θ) on soil penetration resistance (PR). Three sugarcane fields on a Rhodic Eutrudrox were chosen, under a sequence of harvest systems: one manual harvest (1ManH), one mechanized harvest (1MH) and three mechanized harvests (3MH). The different degrees of mechanization were associated to cumulative compaction processes. An electronic penetrometer was used on PR measurements, so that the rod was introduced into the soil by hand (Manual) and by an electromechanical motor (Auto). The θ was measured in the field with a soil moisture sensor. Results showed an effect of θ on PR measurements and that regression models must be used to correct data before comparing harvesting systems. The rod introduction modes resulted in different mean PR values, where the "Manual" overestimated PR compared to the "Auto" mode at low θ.

Resistance of a Red Latosol to Penetration: Comparison of Penetrometers, Model Adjustment, and Soil Water Content Correction

“…The results of field penetrometers depend on user operating speed, which is often challenging to standardize. A change in operating speed alters the force the users applies to insert the equipment rod, which, in turn, changes the result (Filho et al 2014). Bench penetrometers, conversely, are automatic, and the measurements are not influenced by the user.…”

Comparative Measurement of Horizontal Penetrometry with a Focus on the Degree of Soil Compaction in Real Work Conditions

“…Soil compaction measurements have been addressed by several authors. Penetrometric resistance and overall compaction will depend on the soil moisture at the moment and the number of passes of the equipment [17]. In addition to soil moisture, other essential properties include texture, method of cultivation, bulk density, and organic carbon content [18].…”

Soybean (Glycine max (L.) Merr.) Growth, Yield, and Nodulation in the Early Transition Period from Conventional Tillage to Conservation and No-Tillage Systems

“…Specific soil compaction was measured after the soybean harvest (14 October 2020), using a handheld hydraulic penetrometer (GKA 6860; Gouda Geo-Equipment B.V., The Netherlands), at a depth of 10 to 15 cm using a cone rod of diameter 1.28 cm and surface of 1.286 cm 2 , designed to measure heavier soil densities. The soil compaction was displayed by the manometer as specific soil resistance when the penetrometer tip penetrated the ground (i.e., Cl-Cone index, expressed in bars) [37]. The average soil moisture content from a depth of 0 to 15 cm was determined simultaneously with the soil compaction measurements, in close proximity to the hydraulic penetrometer sampling points.…”