Luigi Sartori

Effects of tillage systems on energy and carbon balance in north-eastern Italy

An energy analysis of three cropping systems with different intensities of soil tillage (conventional tillage, CT; ridge tillage, RT; no tillage, NT) was done in a loamy-silt soil (fulvi-calcaric Cambisol) at Legnaro, NE Italy (45°21′N, 11°58′E, 8 m above sea-level (a.s.l.), average rainfall 822 mm, average temperature 11.7°C). This and measurements of the evolution of the organic matter content in the soil also allowed the consequences to be evaluated in terms of CO2 emissions. The weighted average energy input per hectare was directly proportional to tillage intensity (CT > RT > NT). Compared with CT, total energy savings per hectare were 10% with RT and 32% with NT. Average energy costs per unit production were fairly similar (between 4.5 and 5 MJ kg−1), with differences of 11%. The energy outputs per unit area were highest in CT for all crops, and lowest in NT. The RT outputs were on average more similar to CT (−12%). The output/input ratio tended to increase when soil tillage operations were reduced, and was 4.09, 4.18 and 4.57 for CT, RT and NT, respectively. As a consequence of fewer mechanical operations and a greater working capacity of the machines, there was lower fuel consumption and a consistently higher organic matter content in the soil with the conservation tillage methods. These two effects result in less CO2 emission into the atmosphere (at 0°C and pressure of 101.3–103 kPa) with respect to CT, of 1190 m3 ha−1 year−1 in RT and 1553 m3 ha−1 year−1 in NT. However, the effect owing to carbon sequestration as organic matter will decline to zero over a period of years.

Evaluating energy efficiency of site-specific tillage in maize in NE Italy

This paper examine the efficiency of energy use of three conservation tillage practices (SST - sub-soil tillage; MT - minimum tillage; and NT - no tillage) performed within two management zones, previously identified in a field according to the stability of yield variability. Experiments were carried out in 2003 in NE Italy, on a farm near Rovigo, on a 8-ha field with clay soil, in maize (Zea mays, L.). The purpose of the paper is (i) to investigate the energy variability due to these tillage practices performed spatially within two management zones and (ii) to analyze the long-term energetic efficiency for each tillage practice. The energy balance was highest for SST with respect to MT and NT, due to labor and fuel consumption rates. The energy balance was influenced by the spatial pattern of yield, with appreciable differences between practices in terms of both the conversion index of energy for tillage (9.0, 12.6 and 22.8GJha(-1) for SST, MT and NT, respectively) and the energy use efficiency for tillage (8.0, 11.6, 21.8GJha(-1) for SST, MT and NT, respectively). Based on the simulated data and the calibration results, SALUS model proved to be a good tool for analyzing long-term effects of tillage practices on yield. The NT treatment showed the best efficiency over years, due to the low inputs in comparison with the output level.

Environmental and economic benefits of variable rate nitrogen fertilization in a nitrate vulnerable zone

Agronomic input and management practices have traditionally been applied uniformly on agricultural fields despite the presence of spatial variability of soil properties and landscape position. When spatial variability is ignored, uniform agronomic management can be both economically and environmentally inefficient. The objectives of this study were to: i) identify optimal N fertilizer rates using an integrated spatio-temporal analysis of yield and site-specific N rate response; ii) test the sensitivity of site specific N management to nitrate leaching in response to different N rates; and iii) demonstrate the environmental benefits of variable rate N fertilizer in a Nitrate Vulnerable Zone. This study was carried out on a 13.6 ha field near the Venice Lagoon, northeast Italy over four years (2005-2008). We utilized a validated crop simulation model to evaluate crop response to different N rates at specific zones in the field based on localized soil and landscape properties under rainfed conditions. The simulated rates were: 50 kg N ha(-1) applied at sowing for the entire study area and increasing fractions, ranging from 150 to 350 kg N ha(-1) applied at V6 stage. Based on the analysis of yield maps from previous harvests and soil electrical resistivity data, three management zones were defined. Two N rates were applied in each of these zones, one suggested by our simulation analysis and the other with uniform N fertilization as normally applied by the producer. N leaching was lower and net revenue was higher in the zones where variable rates of N were applied when compared to uniform N fertilization. This demonstrates the efficacy of using crop models to determine variable rates of N fertilization within a field and the application of variable rate N fertilizer to achieve higher profit and reduce nitrate leaching.

Comparison of methods for determining cloddiness in seedbed preparation

To determine the optimum degree of roughness of a seedbed, it is necessary to identify parameters that can quantify the cloddiness. This is necessary not only within experimental boundaries, but also to be able to check the quality of the work, and to objectively adjust implements. In this study, the degree of cloddiness of seedbeds was evaluated using three different methods: (1) the sieve method; (2) the image analysis and the standard deviation of the heights defining the soil profile; and (3) the counting, in the field, clods with diameter >40 mm. The degree of correlation between the results obtained by the different methods was also evaluated. The method based on image analysis was well correlated to the sieve method (r2=0.81) and can be used as an alternative for determining the seedbed cloddiness. The standard deviation of the heights defining the profile can be correlated, with a fair approximation (correlation to sieve method r2=0.63), to the degree of cloddiness of the seedbed, although this is also influenced by factors not linked to clod size (oriented roughness). The method based on counting clods with a diameter >40 mm is a simplification of the method based on image analysis; although its correlation to the sieve method is lower (r2=0.53), it lends itself to field application at the stage of adjusting implements. Furthermore, given its simplicity, it appears to be suitable for use by extension services to objectively determine seedbed cloddiness and avoid excessive pulverising of soil. The type of implement affects, sometimes clearly, the relations between the various indexes, and these variations can be explained by the way the implements operate. In particular, a comparison between the sieve and the image analysis demonstrates the different distribution of clods in the vertical profile of the tilled layer; the comparison between image analysis and soil height standard deviation singles out the roughness component not caused by the dimensions of the clods. Finally, an analysis of indexes technical aspects under field conditions is reported.

Application of the Kinect sensor for dynamic soil surface characterization

Agricultural soil roughness is pertinent to important agricultural phenomena, such as evaporation, infiltration or compression. Monitoring roughness variations would make possible the improvement of tillage operations. In the present work, implementation of the Microsoft Kinect™ RGB-depth camera for dynamic characterization of soil micro-relief is proposed and discussed. The metrological performance and the effect of the operating conditions on three-dimensional reconstruction was analyzed considering both laboratory tests on calibrated reference surfaces and field tests on different agricultural soil surfaces. Data set analysis was made on the basis of surface roughness parameters, as defined by ISO 25178 (2012) series: average roughness, root mean square roughness, skewness and kurtosis. Correlation between different tillage conditions and roughness parameters describing soil morphology was finally discussed.

Evaluating the impact of soil conservation measures on soil organic carbon at the farm scale

The study compares the CO2 emission and sequestration patterns of agricultural soils.Field measurements were used to calibrate first and then validate the SALUS model.Simulations indicated that SOC oxidation rates were substantially lower under No-Tillage.This highlights the benefits of NT adoption in terms of fertility and CO2 mitigation. No-tillage (NT) is considered the least invasive conservation agriculture technique and has shown to be the effective in increasing soil C stocks, and reducing losses compared to others tillage systems. In Italy, the Veneto Region was the first to establish a subsidies scheme aimed at promoting the adoption of NT practices. This program encourages farmers to perform direct seeding, alternate autumn and winter crops and maintain soil cover throughout the year by leaving crop residues or sowing cover crops.The goals of this study were to: (i) compare the CO2 emission and soil C sequestration patterns of agricultural soils under CT and NT management practices in the Veneto region and (ii) analyse the potential mid-term benefits (20102025) of NT management in terms of soil organic C dynamics and CO2 balance. Agronomic data and soil organic carbon levels were measured from 2010 to 2014 in eight farms in the Veneto region that had adopted CT and NT techniques. Field measurements were used to calibrate first and then validate the SALUS model to compare the mid-term impact of CT and NT practices using climate projections. SOC carbon pools in the model were initialized using the procedure described in Basso et al. (2011c). This is the first study to employ a model using such an extensive dataset at the farm level to assess the CT and NT strategies within this region.Results of this research will assist farmers and policy makers in the region to define the tillage systems most suited to improve soil C stocks and thereby minimize CO2 emissions from agricultural soils. Overall, simulations indicated that SOC stocks can decrease under both CT and NT regimes, however SOC oxidation rates were substantially lower under NT. Critically, the greatest reduction in CO2 emission was observed when NT was adopted in soil with high levels of SOM. This highlights the benefits of NT adoption in terms of soil fertility preservation and CO2 emissions mitigation.

A Feasibility Study on the Use of a Structured Light Depth-Camera for Three-Dimensional Body Measurements of Dairy Cows in Free-Stall Barns

Frequent checks on livestock’s body growth can help reducing problems related to cow infertility or other welfare implications, and recognizing health’s anomalies. In the last ten years, optical methods have been proposed to extract information on various parameters while avoiding direct contact with animals’ body, generally causes stress. This research aims to evaluate a new monitoring system, which is suitable to frequently check calves and cow’s growth through a three-dimensional analysis of their bodies’ portions. The innovative system is based on multiple acquisitions from a low cost Structured Light Depth-Camera (Microsoft Kinect™ v1). The metrological performance of the instrument is proved through an uncertainty analysis and a proper calibration procedure. The paper reports application of the depth camera for extraction of different body parameters. Expanded uncertainty ranging between 3 and 15 mm is reported in the case of ten repeated measurements. Coefficients of determination R² > 0.84 and deviations lower than 6% from manual measurements where in general detected in the case of head size, hips distance, withers to tail length, chest girth, hips, and withers height. Conversely, lower performances where recognized in the case of animal depth (R² = 0.74) and back slope (R² = 0.12).

On-barn pig weight estimation based on body measurements by a Kinect v1 depth camera

Abstract Information on the daily growth rate of pigs enables the stockman to monitor their performance and health and to predict and control their market weight and date. Manual measurements are among the most common ways to get an indication of animal growth. However, this approach is laborious and difficult, and it may be stressful for both the pigs and the stockman. As a consequence, manual measurements can be very time-consuming, induce costs and sometimes cause injuries to the animals and the stockman. The present work proposes the implementation of a Microsoft Kinect v1 depth camera for the fast, non-contact measurement of pig body dimensions such as heart girth, length and height. In the present work, these dimension values were related to animal weight, and two models (linear and non-linear) were developed and applied to the Kinect and manual measurement data. Both models were highly correlated with the direct weight measurements considered as references, as demonstrated by high coefficients of determination (R 2  > 0.95). Specifically, in the case of the non-linear model based on non-contact depth camera measurements, the mean absolute error exhibited a reduction of over 40% compared to the same non-linear model based on manual measurements (from 0.82 to 0.48 kg).

Three-dimensional sensor for dynamic characterization of soil microrelief

The paper discusses possibilities and limitation of a sensor for dynamic characterization of soil microrelief, analyzing the metrological performance and the effect of the operating conditions on three-dimensional reconstuction. Data sets analysis is made on the basis of surface roughness parameters, as defined by ISO 25178 series. The paper demonstrates how proper calibration and instrument set-up procedures can improve the resolution down to millimeter level, even on relatively large areas. Practical application examples are reported with the result of measurements on soil after operations with different agricultural machines.

Technical aspects concerning the detection of animal waste nutrient content via its electrical characteristics.

The variables influencing corrosion of three metals (galvanised steel, stainless steel, brass) usable for a manure nutrient probe were examined, identifying the best material for field applications. The nutrients in 18 liquid manures were then estimated through the voltage drop between the terminals of a prototype probe. Response Surface Modelling gave the regression functions relating each investigated response only to the statistically-significant factors. After 168h in the manure, it was determined that: stainless steel was the most suitable material for very close electrodes (mass: -1.8% at 15mm), brass can be used with any inter-electrode distance (mass: -13.0% maximum at 35mm). The prototype probe gave reliable estimates (R(2)⩾0.744) of Ntot, Namm, Ptot, Ktot when dry matter and temperature were also accounted for in the regression analysis. Not considering dry matter but just electronically-detectable quantities (temperature, voltage drop), the estimates were only reliable (R(2)⩾0.656) above 20°C.