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The article describes the analysis of results from field tests on ploughing units based on a modular draft device (MDD). This device is named MDD-100 and consists of an energy module and a technological module. The energy module is a universal tractor with a rated draft resistance of 16 kN. The technological module is an additional axle, equipped with an active wheel drive, a threepoint hitch linkage, and a saddle-type semi-trailer. During the working process, the draft resistance of the energy and the technological modules of the MDD-100 add up. As a result, the draft resistance of the latter may reach 26 kN, and more. This allows the MDD-100 to be classified as a draft device in traction class 3 and be used with agricultural machines with a large working width. The MDD-100 was tested with a five-bottom mounted plough with a working width of 1.75 m and a draft resistance of 24-28 kN. The best option for driving the MDD-100 with a plough was its movement with the right-side wheels in the furrow. The draft resistance of the plough would decrease by 12.0%, if the option of the MDD-100 outside the furrow is used. This ensured a 12.8% reduction in the skidding of the MDD-100 wheels and a 13.1% decrease of fuel consumption for the ploughing unit. Compared to a 4WD tractor, the use of a modular draft device with a 6WD wheel arrangement offered a greater stability of the ploughing depth.

The use of agricultural machinery represents the main aspect contributing to the total energy input in the agricultural system. The study evaluated the energy requirements and the work quality of two conventional (threefurrow plough and spading machine) and of four conservation implements (rotary harrow, subsoiler, disk harrow, combined cultivator) for mediumdeep primary tillage in a silty-clay soil, widespread in Central Italy. The tests were carried out with the aim of selecting the most energy-efficient implement. Working speed, force of traction, fuel consumption and energy demands were measured, using a 205 kW instrumented tractor. Cloddiness and roughness of the tilled soil, biomass coverage index and burying degree were evaluated. The conservation tillage implements gave the best results in fuel consumption and energy requirements respect to the conventional implements, with energy savings up to 86% in the case of disk harrow. The rotary harrow showed intermediate values and the best soil refinement. Among the conservation implements, the disk harrow showed the best performance on biomass coverage index (43.8%), while the combined cultivator showed the highest value of biomass burying (87.8%) and the best performance on fuel consumption per hour (25.8 kg h–1).

The introduction of rubber tracks on tractors has allowed more engine power per unit weight than with steel-tracked tractors, together with a reduction in soil compaction and higher on-road speeds. Recently, triangular rubber tracks able to be adapted on conventional wheeled tractors have been introduced. In this context, the goal of the paper is to evaluate the performance of a tractor with four triangular rubber tracks with respect to those of a wheeled tractor; the comparative tests consist of ploughing under on low trafficable and workable soil. The results obtained have shown a higher tractive efficiency, lower soil compaction and up to 20% lower specific fuel consumption for the fully tracked tractor. These results are in accordance with previous tests conducted with the triangular rubber tracks on highly trafficable soil, although in the present case, the dynamic traction ratio is markedly lower due to the low trafficable soil. The use of triangular rubber tracks is therefore justified on low trafficable soils and more in general on different soil conditions, since the soil is less compacted by such traction device.

Compared to traditional plowing and minimum tillage, the sod seeding technique has been tested in order to evaluate the differences in energy consumption, labor and machinery requirement and CO2 emission reduction. The experiments were conducted on winter cereal seeding in a Po valley farm in October 2011. The tests were carried out as follows: wheat variety seeding, over corn and alfalfa crops, in large plots with three repetitions for each thesis. They included: sod seeding anticipated by round up weeding in the case of the plots over alfalfa; traditional plowing at 35 cm followed by rotary tillage and combined seeding (seeder plus rotary tiller); minimum tillage based on ripping at the same depth (35 cm) and combined seeder ( seeder plus rotary tiller). The following farm operations - fertilizer, and other agrochemical distributionshave been the same in all the considered theses. The results, statistically significant (P

In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of rototilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the SAF (Scienze Agrarie e Forestali) Department of the University of Palermo in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of three machines for shallow tillage: a chisel plough (CP), a rototilling (RT) and a spading machine (SM) on penetration resistance in semi-arid environments of the Mediterranean basin. No tillage was also included. Penetration resistance (PR) was surveyed for all the treatments to a depth of 300 mm with an electronic dynamometer. The treatments consisted in the execution of a shallow tillage to a depth of 150 mm. SP treatment allowed us to obtain PR lower values throughout the tillage profile than RT, CP and NT. It follows that the type of machine used influences soil PR, and then the soil water storage capacity, key factor for the agricultural productions in semi-arid environments as in Sicily.

Noise in agriculture is one of the risk factors to be taken into account in the assessment of the health and safety of workers; in particular, it is known that the tractor is a source of high noise. The Italian Low Decree 81/2008 defined the requirements for assessing and managing noise risk identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This paper concerns the analysis of the noise risk arising from the use of a tracklaying tractor during field operations carried out in the vineyard. The objective of this study was to evaluate the noise level that comes close to the ear of the operator driving the tractor measuring the values of equivalent sound level (Leq(A)) and peak sound pressure (LCpk). We considered four options related to the same tractor coupled with the following tools to perform some farming operations: rototilling, chisel plough, flail mowers and vibro farmer. We considered three test conditions: T1 in flat (slope 0%), T2 uphill and T3 downhill (both 30% slope). The instrument used for the measurements is a precision integrating portable sound level meter, class 1, model HD2110L by Delta OHM, Italy. Each survey lasted 2 minutes, with an interval of measurement equal to 0.5 s. The tests were performed in compliance with the standards ISO 9612 and ISO 9432. The results show that the measured sound levels exceed the limits allowed by the regulations in almost all the test conditions; values exceeding the threshold limit of 80 dB(A) were recorded coming up to a maximum value of 92.8 dB(A) for flail mowers in test T1. When limits imposed by the regulations are exceeded, the operator is obliged to wear the appropriate Personal Protective Equipment.