Andrea Pezzuolo

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.

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.

Critical Factors in Cantilever Near-Field Scanning Optical Microscopy

An important technique for high resolution optical imaging, beyond the diffraction limit, of nanostructured surfaces is aperture near-field scanning optical microscopy (NSOM). Even though NSOM has already demonstrated its good performance in a number of different applications, its quantitative application is still a challenge, due to a number of factors, which commonly influence the quality of the measurement output and consequently extrapolation of quantitative parameters. In this paper, a systematic study is reported, analyzing the effect of the most critical factors in cantilever NSOM measurements, with particular attention to tip geometry and aperture, scanning configuration, and scan mode. Investigations have been carried out on a commercial instrument, in combination with reference standard for NSOM calibration (as for instance the Fisher pattern) and other samples opportunely produced for this paper.

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).

Traffic effects on soil compaction and sugar beet (Beta vulgaris L.) taproot quality parameters

Soil compaction is a critical issue in agriculture having a significant influence on crop growth. Sugar beet ( Beta vulgaris L.) is accounted as a crop susceptible to compaction. Reduction of leaf area, final yield, and root quality parameters are reported in compacted soils. The most obvious visual indicator of topsoil compaction is root depth affected by agricultural tractor and machinery traffic up on the soil. Such indicators are mainly correlated to initial soil condition, tyre features, and number of passages. Monitoring and controlling frequency and position of machine traffic across the field, in such a way that passages are completed on specific, well-defined tracks, can assist with minimization of compaction effects on soil. The objective of the present work was to analyze the subsoil compaction during the growing period of sugar beet with different farming approaches including controlled traffic passages and random traffic. To this end, tests were carried out following each agro technical operation using penetrometer readings in order to monitor the state of cone-index after each step. In addition, at the harvesting time, root quality parameters were analyzed with particular attention to length and regularity of the taproot, total length, circumference, mass, and above-ground biomass. Such parameters were usefully implemented in order to evaluate the effects of controlled traffic passages compared to the random traffic in a cultivation of sugar beet. Results highlight how an increase in crop yield, derived from samples monitored, higher than 10% can be expected with implementation of a careful traffic management.

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.

Elastic-properties measurement at high temperatures through contact resonance atomic force microscopy

Miniaturization of products and need for further improvement of machines performance introduce new serious challenges in materials characterization. In particular non-destructive mechanical testing in the sub-micrometer scale is needed to better understand and improve micro-manufacturing operations. To this regard, some open issues are of particular interest: low depth of penetration, high lateral resolution and measurements at elevated temperatures. An interesting solution is given by acoustic microscopy techniques, which can be successfully implemented for advanced research in surface elasticity, allowing fast direct and non-destructive measurement of Young’s modulus and related surface parameters. In this work an instrument set up for Contact Resonance Atomic Force Microscopy is proposed, where the sample with is coupled to a heating stage and a piezoelectric transducer directly vibrate the cantilever during scanning, in order to allow exploitation of high resolution measurements at relatively high temperatures. Such instrument set up was undergone a set of calibration experiments in order to allow not only qualitative but also quantitative characterization of surfaces. The work was completed with a feasibility study with mechanical and topography measurements at temperatures as high as 150°C, with lateral resolution lower than 100 nm.

On-Barn Pig Weight Estimation Based on Body Measurements by Structure-from-Motion (SfM)

Information on the body shape of pigs is a key indicator to monitor their performance and health and to control or predict their market weight. Manual measurements are among the most common ways to obtain an indication of animal growth. However, this approach is laborious and difficult, and it may be stressful for both the pigs and the stockman. The present paper proposes the implementation of a Structure from Motion (SfM) photogrammetry approach as a new tool for on-barn animal reconstruction applications. This is possible also to new software tools allowing automatic estimation of camera parameters during the reconstruction process even without a preliminary calibration phase. An analysis on pig body 3D SfM characterization is here proposed, carried out under different conditions in terms of number of camera poses and animal movements. The work takes advantage of the total reconstructed surface as reference index to quantify the quality of the achieved 3D reconstruction, showing how as much as 80% of the total animal area can be characterized.