Fundamentals of Precision Agriculture

Precision agriculture or precision farming is the targeted application of crop input according to the locally determined crop needs. Therefore, it is the geo-referenced application of crop inputs, whose rates should be those required by the crop. The most essential points of information about the topic being described are: overview; brief history of precision agriculture; theoretical basics of precision agriculture; precision agriculture cycle; geo-referenced measurement of within-field parameters; analysis and interpretation of geo-referenced data for mapping within-field parameters; spatially variable rate application of crop inputs; instruments for precision agriculture; current scenario of precision agriculture; current scenario of precision viticulture; Global Navigation Satellite Systems (GNSS) and differential correction technique; proximal sensors of within-field soil and crop parameters; remote sensing from Unmanned Aerial Vehicles (UAVs) and satellites; devices for setting up and controlling spatially variable rate crop input application; assisted guidance systems of agricultural machines; perspectives of precision agriculture

A System for the Real-Time Geo-Referenced Measurement of Soil Parameters

The aim of this research is to develop a system for accurately measuring in real-time, collecting and processing a high amount of geo-referenced data of soil physical-mechanical parameters, e.g. cone penetrometer resistance, index of soil compaction, and draft force. The system for measuring the soil cone penetrometer resistance is comprised of a load cell, connected to a rod, ending with a cone, and is mounted on a frame, fixed to the front part of a tractor. The system for measuring the draft force required to till the soil is comprised of a load cell, mounted on the hitch hook of a tool carrier, towed by the tractor. Moreover, in order to test the usefulness of the system with different types of linkage tractor-implement, two other load cells were mounted, respectively, on the top link and the right point of the three-point hitch of the tool carrier. The signals of the load cells and of a DGPS mobile receiver are acquired by a portable computer, by means of a Virtual Instrument developed in LabVIEW environment. The results of the first tests, carried out in a field in inland Sicily, showed that: the system is able to log data with a sampling frequency adjustable from 1 to 10 Hz; it is able to accurately measure and collect in real-time a large amount of data, which can be easily processed by means of a data sheet, a GIS or another software usable for measuring the within-field spatial variability of soil physical-mechanical parameters; the absolute value of the force measured on the hitch hook of the tool carrier is proportionally correlated to that measured on any point of the three-point hitch of the same one

Use of Sentinel-2 Satellite for Spatially Variable Rate Fertiliser Management in a Sicilian Vineyard

Satellites can be used for producing maps of within-field crop and soil parameters and, consequentially, spatially variable rate crop input application maps. The plant vegetative vigour index (i.e., Normalised Difference Vegetation Index—NDVI) and the leaf water content index (i.e., Normalised Difference Water Index—NDWI) maps were used to study—through both time and space—the phenological phases of two plots, with Syrah and Nero d’Avola grapevine varieties, in a Sicilian vineyard farm, located in Naro (Agrigento, Sicily, Italy). The aim of this work is to produce spatially variable rate nitrogen fertiliser maps to be applied in the two vineyard plots under study as well as to understand when they should be fertilised or not according to their target crop yields. The average plant vegetative vigour and leaf water content of both the plots showed a high temporal and spatial variability during all phenological phases and, according to these results, the optimal fertilisation time should have been 12 April 2021. In fact, this crop operation is aimed at supporting the vegetative activity but must be performed when the soil water and, therefore, the plant leaf water content are high. Therefore, spatially variable rate fertilisation should have been performed around 12 April 2021 in both plots, using previous NDVI maps and taking into consideration two management zones. This work demonstrates the usefulness of remote sensing data as Decision Support Systems (DSS) for nitrogen fertilisation in order to reduce the production cost, environmental impact and climate footprints per kg of produced grapes, according to the European Green Deal challenges

A System to Simplify the Use of Mounted Shakers for Harvesting Olives and Dry Fruits

The shakers for harvesting olives and dry fruits have reached a high standard and their use is increasing rapidly. In order to satisfy the different demand, manufacturers offer a wide range of shakers, from the more expensive self-propelled ones to those to be mounted on the tractor’s power lift, with shaking headers of different mass and size, suitable for the different orchard characteristics. Self-propelled shakers have high steering capacity and optimum visual field for the operator, so their working capacity is very high with respect to that of mounted shakers, which are less expensive but have lower steering capacity and a limited view on the header. Therefore the approaching of mounted shakers to the plant and the fastening of the header to the trunk or branch of the tree is more difficult, and a second operator to pilot the tractor driver is needed, in order to increase the machine working capacity and to avoid plant and/or shaker damages. This paper proposes to use a system composed of a CCD video camera, installed on the frame of a mounted shaker and connected to a TFT monitor, fitted in the tractor cab. Comparative tests with and without the above system were carried out. The video camera was mounted on the shaker frame. The system is relatively cheap, user-friendly and can be mounted on any shaker. It provides the driver with an easy view of the lower dead angle and increases the working capacity and productivity of the machine

Nomenclature for Hydrogeological Instability Risks

The nomenclature for hydrogeological instability risks includes four main risks, which are distinguished according to the risk causes : 1) hydrogeological risk, that is slowly caused by natural factors (e.g. collapse landslides in a calcareous cliff in uninhabited areas and erosion along a marly-calcareous slope) in environments where human activities are minimal, i.e. woods, forests and mountain pastures; 2) hydraulic-pedological farming risk, that implies the occurrence of landslides in every winter and is caused by incorrect crop selection, not suitable for the soil and climate parameters (e.g. on a hilly slope with a clay vertisol type with a landslide having different fronts, when the arable land is cultivated with a cereal-legume crop rotation), or the presence of springs with missing drainage in clay soils with a high gradient; 3) hydraulic-infrastructural risk, that is caused by the building up of infrastructures not suitable for the surrounding environment, as they change the downflow of shallow water; 4) hydraulic-infrastructural-pedological-management risk, that is caused by crop operations not suitable for soil and crop parameters, where the selected cultivated plant species are suitable for the environment and field improvements change water downflow (e.g. in soils along hilly calcarenite slopes cultivated with olive orchards, where up-down soil tillage causes shallow water erosion)

Accuracy assessment and position correction for low-cost non-differential GPS as applied on an industrial peat bog

A low-cost, non-differentially corrected hand-held GPS receiver was tested on an industrial peat production bog. A correction procedure (‘pseudo-differential correction’) was derived that corrected data points to the nearest position on a line defining the centre of each 15-m wide field. The result was a corrected log of track points for each field for all points lying along the field. It was found that the mean orthogonal distance from a field centreline was linearly correlated with mean uncorrected GPS data error (r2=0.99) such that as GPS error increased so the accuracy obtained by correction decreased. For a signal with a mean uncorrected error of 30 m it was possible to reduce the error to 12 m. The results are discussed within the design requirements of a precision peat production system for peat energy. It is concluded that low-cost GPS could be used without differential correction as part of a precision peat production system because over 80% of the time positional error could be constrained to within 15 m. When compared with the perceived patterns of variability and the 30-m resolution of Landsat imagery which can be used for making application maps, this is acceptable

Italian Potential Biogas and Biomethane Production from OFMSW

This work is aimed at predicting the potential biogas and biomethane production, using the Organic Fraction of Municipal Solid Waste (OFMSW), in Italy, where 1388 Anaerobic Digestion (AD) plants (power of 7.4 TWh, equal to 640.4 ktep) are nowadays available. In order to compute the potential biogas and biomethane production in the 20 Italian regions, the data about OFMSW production in 2010-2013 period have been evaluated. The Italian production of OFMSW, that was 5.2 million tons in 2013 (18% of MSW), could be used inside bioreactors for producing biogas and digestate, that must be aerobically composted into a biofertiliser. In 2013, the Italian potential biogas production from OFMSW was 739 million m3, that is equal to 444 million m3 of biomethane. The highest biogas production from OFMSW was in Lombardy region (143 million m3), having a potential biomethane production of 86 million m3. The highest OFMSW production per inhabitant was in Emilia-Romagna region (142 kg). Yet, if OFMSW was 37% of MSW, the potential biogas and biomethane production should be increased: the biomethane production increase would be 486 million m3, of which the maximum would be in Sicily region. The biogas produced can be used for generating heat and electricity or upgraded into biomethane, distributed at dedicated stations and useful as biofuel for powering means of transport. This biofuel would replace natural gas, and, therefore, allow a reduction of GreenHouse Gas emissions of 200 g of CO2 kWh-1 (5.5 times lower) and the import of fossil fuels from abroad

A system for spatially variable rate fertiliser application

The crop yield can be spatially variable within the same field, because of spatially variable soil characteristics (slope, texture, pH, etc.), influencing the soil nutrient content (of nitrogen, phosphorus, potassium, etc.). Because of this within-field spatial variability, in the precision agriculture cycle, the targeted fertiliser spreading can be highly profitable for both environment protection and cost saving. For this aim the yield and, then, the soil nutrient content must be measured on a localised basis and, therefore, mapped. Relying on the yield map and on the map of each nutrient available in the field it is possible to produce the fertiliser application map, which must be stored on a portable computer, in order to perform the spatially variable rate fertiliser spreading. For this aim an electronic system able to apply fertiliser rates proportionally related to the machine forward speed is also needed; this system can be mounted not only on any pneumatic spreader but also on any centrifugal spreader with setting up system working by gravity. Yet, the fertiliser spreaders produced by different manufacturers, which are equipped with systems able to apply not only rates proportionally related to machine forward speed but also spatially variable rates, are very expensive. Therefore, the I.T.A.F. Department designed, developed and set up a system for spatially variable rate fertiliser application, compatible with most DGPS and spreaders able to apply rates proportionally related to the machine forward speed. The system is constituted by a data sensing system (DGPS and Doppler radar), a data processing system (portable computer, with a specifically developed software called Precision Agriculture Controller) and an active and control system (Land Manager of DICKEY-john with built-in display and keyboard), able to apply rates proportionally related to machine forward speed, by varying the size of the two hopper openings. The software is able to: receive and interpret DGPS position data and compare them with the fertiliser application map, in order to identify the rate related to the actual machine position; transmit commands to Land Manager; log the machine track and the applied rates

Proposal of a Nomenclature for Hydrogeological Instability Risks and Case Studies of Conservative Soil Tillage for Environmental Protection

In order to implement environmental protection, within the Soil Cadastre, previously proposed as a multipurpose inventory that aims to promote sustainable soil uses, the hydrogeological instability caused by human activities is the focus of this work. These activities can be aimed at sustainable agricultural soil use or the building of roads to allow the access to the fields. The soil’s hydrogeological instability causes the unsustainable use and management of a cadastral parcel. Therefore, the aim of this work is to propose a nomenclature for hydrogeological instability risks, as well as the best practices of conservative soil tillage in case studies, in order to reduce environmental impact. According to the proposed Soil Cadastre, the missing environmental sustainability of a parcel and the reason for this must be communicated to the field owner or manager. In a hilly area of inland Western Sicily, four main risk types of hydrogeological instability were identified: hydrogeological instability (caused only by natural factors); hydraulic-pedological-farming instability (crop not suitable for the field for missing or insufficient soil drainage and landslides); hydraulic-infrastructural instability (built up infrastructures unsuitable for the site); hydraulic-infrastructural-pedological-management instability (field improvements changing the downflow line and crop operations not suitable for the soil and climate parameters). The farm owner or manager must be informed about the risk type affecting their fields in order to perform the best practices (i.e., conservative soil tillage), for implementing or restoring a sustainable soil use or management in each cadastral parcel