Tillage and Crop Rotation Effects on Mechanical Properties and Structural Stability of a Sandy Loam Soil in a Semi-arid Environment Chakraborty Debashis*, Mondal Surajit1, Das Anupam2, Paul Amrit3, Thomas Paulson4, Aggarwal Pramila, Behera U.K.5, Sharma A.R.6 Division of Agricultural Physics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012 1Division of Land and Water Management, ICAR-RCER, Patna, 800141, Bihar 2Department of Soil Science and Agricultural Chemistry, Bihar Agricultural University, Sabour, 813210, Bihar 3ICAR-Indian Agricultural Statistics Research Institute, New Delhi, 110012 4Krishibhavan Payam, Kannur, 670706 5College of Agriculture, Kyrdemkulai, Central Agricultural University (Imphal), College of Post Graduate Studies Campus, Umiam, Ri-Bhoi, 793103, Meghalaya 6Rani Lakshmi Bai Central Agricultural University, Jhansi, 284003, Uttar Pradesh *Corresponding author (Email: debashisiari@gmail.com)
Online published on 2 September, 2019. Abstract Tillage has strong influence on soil architecture and thus modifies soil matrix-pore system. Short-term (7 years) changes in soil mechanical properties (macro-and micro-level) were evaluated in pigeon pea-wheat (P-W), cotton-wheat (C-W) and maize-wheat (M-W) cropping systems (CS). Tillage systems were: no tillage (NT) and conventional tillage (CT) with or without crop residue retention (+R/-R). Soil bulk density didn't change appreciably. Soil resistance to penetration at 10–20 cm layer reduced under NT system with residue retention (NT+R), owing to greater soil water content. Maintaining residue, irrespective of tillage, improved soil aggregation and bulk soil organic carbon content (total, particulate and KMnO4-oxidizable C), promoting a better root-zone hydro-physical regime in all CS. Effect of tillage on water-stability of aggregates was observed at 0–7.5 cm layer only, in air-dried, compared to field-moist samples. The tillage-CS interactions had impact on mean weight diameter (MWD) of air-dried aggregates at 0–7.5 cm layer. The MWD was higher in NT+R under P-W than any other tillage/residue-CS combination. Residue incorporation in CT also resulted in greater macro-aggregates (>0.25 mm), and thereby larger MWD. Disruption of aggregates through different energy inputs was the least under NT+R, indicating predominantly higher amount of water-stable aggregates, providing a better soil structure. Top Keywords No tillage, cropping system, mean weight diameter, organic carbon. Top |