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For granular materials, discrete element modeling is one of the best computer tools to simulate their behavior and interactions. A field experiment was carried out to evaluate the performance of disc furrow openers in paddy soil. Discrete element simulation was done to develop a 3D DEM model for notched, toothed and double disc furrow openers using EDEM software. Hertz Mindlin contact model with bonding was applied for simulation to fulfill the obligations of the soil moisture and bonding between the cohesive particles. Simulated and field experimental data were compared to determine the applicability in the different working conditions. The results of the simulation validated the applicability of the Hertz-Mindlin contact model with bonding to simulate the no till paddy soil using an extremely narrow tillage tool. The calibrated value of normal and shear stiffness was 5x107 N/m, and the calibrated value of bond normal and shear strength was 3x107 Pa. The relative error (-1.7% to 20.6%) for the double disc furrow opener was lower as compared with that notch typed (29.2% to 44.4%) and toothed type (31.5% to 45.9%) furrow openers. [ABSTRACT FROM AUTHOR]

• BDAM inoculation resulted in removal of BS from contaminated soil. • The consortium BDAM inoculation has significantly enhanced plant growth. • Strains of the consortium BDAM colonized in plant rhizo- and/or endosphere. • Plant-bacterial association proved to be effective for remediation of BS contaminated soil. Plant-bacterial mutualism has tremendous potential for remediation of herbicide contaminated soils. Generally, bacterial inoculation helps plants to grow well in the contaminated environment. Here, we investigated the impact of bispyribac sodium (BS) degrading bacterial consortium (BDAM) on BS remediation, plant growth promotion and BS accumulation in plant parts. Wheat (Triticum aestivum) was planted in BS spiked soil and inoculated with BDAM. Inoculation showed a beneficial effect on plant biomass production and degradation of BS in the rhizosphere and the rhizosheath. After 40 and 60 days of inoculation, the degradation of BS was more than 96% and approximately 100% respectively in the planted and inoculated soil spiked with 2 and 5 mg kg−1 BS. However, in planted and un-inoculated soil, the degradation of BS was 72% after 60 days of sowing. Furthermore, inoculated bacterial strains colonized both in rhizo- and endosphere of the inoculated plants. In comparison with the un-inoculated soil, significantly less accumulation of BS was found in the roots and shoots of the plants growing in inoculated soil. We report the efficiency of plant-bacterial partnership for enhanced biodegradation of BS and to eliminate the BS residual toxicity to non-target plants. [ABSTRACT FROM AUTHOR]

Discrete element modelling (DEM) is widely regarded as one of the most effective methods for simulating the soil-to-tool interaction. Discrete element simulations were carried out to evaluate the performance of mouldboard plough in paddy soil. The Hertz-Mindlin bonding contact model was applied to develop the bonding between soil particles. Maximum soil draught force (3.64 N) was obtained at 15 cm depth. The force decreased from 1.98 to 1.10 N as the depth decreased from 10 cm to 5 cm. From the results, the DEM have the potential to predict cutting forces of mouldboard plough in all direction draught, vertical and side (Fx, Fy and Fz. A linear relationship was observed throughout the simulation process between working depths. It is concluded that the EDEM model has the potential to serve as a reliable tool for determining the soil-tool interaction. [ABSTRACT FROM AUTHOR]

A knowledge-based fuzzy logic model was developed on experimental data and used to predict the draft, side and vertical forces and soil disturbance area by disc tillage tool operation. The laboratory research work was conducted to evaluate the performance of the disc tool at three working speeds (1.25 m/s, 1.98 m/s and 2.47 m/s, respectively) and depths (0-5 cm, 5-10 cm and 10-15 cm, respectively) on paddy soil under soil-bin environment. Further, draft (Fx), side (Fz) and vertical (Fy) forces of disc and soil disturbance area were assessed and predicted towards working speeds and depths. A fuzzy prediction model with two input variables (speed and depth) and four output variables was developed and the Mamdani inference approach was used. Draft, side and vertical forces of disc and soil disturbance area were positively responded 0.97, 0.95 and 0.84 and 0.99, respectively. The prediction results showed a close relationship between measured and predicted data. Similarly, the measured and predicted results revealed that the draft, side, vertical forces, and soil disturbance area slightly increased, while increasing the speed and depth of the disc tool. Furthermore, disc forces and soil disturbed area were highly significant (p<0.05) for higher speed towards depth. It was concluded that the fuzzy model may be introduced for predicting the disc forces and soil disturbance area during the disc tillage tool operation with high accuracy. [ABSTRACT FROM AUTHOR]