Pengujian Cone Index pada Tanah Kering dengan Menggunakan Digital Penetrometer

Persiapan lahan pada budidaya pertanian merupakan salah satu faktor penting pendukung produktivitas pertanian. Tahanan penetrasi tanah dapat digunakan untuk menggambarkan kondisi ketahanan tanah terhadap penetrasi akar. Penelitian ini bertujuan untuk mengetahui hubungan antara kadar air tanah dengan CI menggunakan penetrometer digital. Pengujian penetrasi tanah yang dilakukan pada lahan kering tanpa pengolahan tanah dengan kedalaman 0 – 60 cm. Tekstur tanah yang diuji berdasarkan standar Japanese Soil Physics adalah Loam. Penetrometer yang digunakan termasuk kedalam penetrometer kerucut tipe laju konstan. Terdapat keeratan yang kuat antara CI dan KA, z pada pengujian penetrasi tanah di lahan kering tanpa pengolahan dengan nilai Multiple R sebesar 0.9688. Berdasarkan hasil pengujian ANOVA didapatkan pengaruh KA terhadap CI secara signifikan dan positif.

Soil compaction response to wheel traffic in the Rolling Pampas region of Argentina

The present work shows the effects of the different agricultural wheels traffic on the soil physical properties on a Typic Argiudoll soil worked under no-tillage cropping system. Soil compaction produced by traffic was quantified through these parameters: a) cone index, b) rut depth and c) soil water content at the traffic moment. Grain chaser, sprayer, harvester combine and tractor equipped with commonly used wheels in the study area were tested. The main results obtained showed that the tyres with the highest inflation pressure and tyre ground pressures produced the highest values of cone index and rut depth. Typic Argiudoll soil worked under continuous no-tillage cropping system is not able to constrain topsoil and subsoil compaction when it is wheeled by tyre with ground pressures greater than 77.6 kPa. Highlights Soil compaction causes a reduction in root growth and yield in many crops. Soil under a no-tillage system does not limit topsoil and subsoil compaction when wheeled by tyres with ground pressures greater than 77.6 kPa When the machinery load increases on soils with high bearing capacity (soils under a long-term no-tillage system), the subsoil compaction problems increase.

Comparison of Selected Terramechanical Test Procedures and Cartographic Indices to Predict Rutting Caused by Machine Traffic during a Cut-to-Length Thinning Operation

Timber harvesting operations using heavy forest machinery frequently results in severe soil compaction and displacement, threatening sustainable forest management. An accurate prediction of trafficability, considering actual operating conditions, minimizes these impacts and can be facilitated by various predictive tools. Within this study, we validated the accuracy of four terramechanical parameters, including Cone Index (MPa, Penetrologger), penetration depth (cm, Penetrologger), cone penetration (cm blow−1, dual-mass dynamic cone penetrometer) and shear strength (kPa, vane meter), and additionally two cartographic indices (topographic wetness index and depth-to-water). Measurements applying the four terramechanical approaches were performed at 47 transects along newly assigned machine operating trails in two broadleaved dominated mixed stands. After the CTL thinning operation was completed, measurement results and cartographic indices were correlated against rut depth. Under the rather dry soil conditions (29 ± 9 vol%), total rut depth ranged between 2.2 and 11.6 cm, and was clearly predicted by rut depth after a single pass of the harvester, which was used for further validations. The results indicated the easy-to-measure penetration depth as the most accurate approach to predict rut depth, considering coefficients of correlation (rP = 0.44). Moreover, cone penetration (rP = 0.34) provided reliable results. Surprisingly, no response between rut depth and Cone Index was observed, although it is commonly used to assess trafficability. The relatively low moisture conditions probably inhibited a correlation between rutting and moisture content. Consistently, cartographic indices could not be used to predict rutting. Rut depth after the harvester pass was a reliable predictor for total rut depth after 2–5 passes (rP = 0.50). Rarely used parameters, such as cone penetration or shear strength, outcompeted the highly reputed Cone Index, emphasizing further investigations of applied tools.