Precision agriculture solutions are utilised in every phase of the farming cycle from land preparation and planting to irrigation and water management, nutrient and pest management, harvest, and also in the data collection and analysis, writes Mike Martinez, Marketing Director, Trimble Agriculture
The world’s population is predicted to increase to nine billion people by the year 2050, and the current food production rate falls significantly short of meeting this increased need. Concurrently, issues such as water conservation and minimising nutrient runoff into streams and waterways continue to be a top priority for many regions across the globe. So how will farmers best achieve these goals? The answer is through precision agriculture.
Precision agriculture has transformed the way farming is conducted today. It enables a farmer to monitor his fleet remotely, map field boundaries, geo-reference crop scouting information, conduct soil analysis, monitor yield, or create prescription maps to target each area of a field uniquely. Precision agriculture is based on location-based technologies such as GPS and GIS, and there are many applications for its use on the farm.
Soil mapping technology
Understanding soil properties and variations is a critical step in the farming process. With accurate soil data, farmers can make better decisions about their operations, leading to a positive effect on yield. 3D soil mapping solutions like Trimble’s Soil Information Systems (SIS) use advanced, above and below ground, sensors combined with GPS, along with intelligent targeting and geo-processing algorithms to produce high resolution, accurate soil and topographic information of the top four feet of the earth’s surface.
By analysing soil variability and patterns prior to sampling — and by using industry-exclusive data acquisition and analysis software (DAAS) — soil information systems provide targeted recommendations on the best locations where soil samples should be taken. In some cases this reduces the number of samples required to provide high-quality information by as much as 60% over traditional grid sampling methods.
Soil information systems follow a five step process. In step one, the field boundary is defined using the Surfer, which is an ATV equipped with high-resolution GPS, an electromagnetic (EM) sensor, and an onboard computer that runs the software.
The second step, also using the Surfer, fills in the detail within the perimeter defined in step one. The system collects variability information using the electromagnetic sensor in the sled and its corresponding RTK-accurate GPS position.
In step three, soil characterisation, or diving, occurs. The Diver has an RTK corrected GPS, a geophysical soil probe with several SIS-specific sensors, and an on-board computer. The software collects the locations on the field which are targeted based on the variability from the first step. The Diver software guides the operator to a point, and the geophysical probe is pushed into the ground to collect continuous data streams for tip force, sleeve friction, moisture, and electrical resistance.
Step four is the soil chemical property characterisation portion of the survey. The software again processes all of the data collected from the Surfer and the Diver and selects locations x, y, and z throughout the field where cores will be taken to maximise the soil three dimensional representation. Finally in step five all of this information is processed using algorithms and databases to interpret the data and then create the multi-layer maps.
Soil information systems produce maps for dozens of physical and chemical soil characteristics. With this information, farmers and their agronomists are able to implement more effective solutions for each area of their field. For example, knowing the soil’s plant available water capacity, can aide a farmer’s decisions in irrigation layout, scheduling, moisture sensor targeting, root stock selection, and many other management decisions.
Utilising precision agriculture technology in irrigation can help farmers optimise their use of water and satisfy regulatory requirements, while helping to increase the yield. Irrigation solutions like Trimble’s GPS-controlled Irrigate-IQ enable farmers to remotely control irrigators, create irrigation plans, perform variable rate irrigation, and receive reports, resulting in reduced trips to the field. With such precision solutions, farmers are able to see the status of their pivots, in which direction they are traveling, the heading, pump pressure, pivot voltage, and type of material being dispersed (water, fertigation, or effluent). The solution also gives farmers the ability to remotely start or stop their pivots, choose the direction, turn the pump on or off, or switch the type of material being dispersed.
By utilising variable rate irrigation, farmers can control the application of water, fertigation, or effluent down to the individual nozzle. This allows for highly targeted application to ensure the right amount is applied in the right place, and results in better water optimisation across the farm. For example, if a farmer has conducted soil analysis, he is aware of his soil’s varying properties, topography, and potential issues. The farmer can then work with his local agronomist to have his soil map analysed and converted into a variable rate irrigation prescription that is specific to each area of the field. The irrigation prescription may require more or less water in specific areas due to topography, soil, and crop type.
Satellite imagery is a key area that is helping farmers to operate more efficiently by enabling better monitoring of crop health. Precision vegetation health solutions like Trimble’s PurePixel provide specialised processing of multi-spectral, geo-referenced images used for crop health analysis. Field images processed with such technology provide a visual representation of the selected field’s crop health or maturity level based on a colour-coded index.
Such technology produces a vegetation vigor index map, which is a calibrated representation of vegetation health that can be used to track crop growth and measure the magnitude of difference between areas. Users can compare multiple images of the same area and visually detect changes in crop health over time. This feature is especially useful for monitoring expected progress in crop growth or improvements in crop health when treating underperforming areas within fields.
Satellite imagery can provide numerous benefits. For example, farmers can save time by quickly viewing large areas and identifying specific locations where issues may be present, enabling the farmer or trusted advisor to travel only to the targeted areas versus scouting the entire field.
Unmanned aircraft systems
Another area offering great potential in the agriculture industry is the use of Unmanned Aircraft Systems (UAS) to help farmers, agronomists, and other agriculture service providers to easily monitor crop health. While the most common use of aerial imaging on crops is to check for nitrogen or water stress, growers and agronomists can view crops spatially, too. If the bare field was captured before planting, the height of a crop can be measured in the prime growing months. Similarly, missing or rain-damaged plants can be seen in a terrain map.
Aerial imaging solutions like Trimble’s UX5 use a combination of technologies including GPS, radio, photogrammetry, and remote sensing, and come with a camera modified to capture the near-infrared spectrum, which helps in deducing vegetation indexes for crop health assessment. The output of a single flight provides geo-referenced precision images, a digital surface model (DSM) showing elevations as a colour image, and a dense 3D point cloud of the terrain that includes elevations.
With these aerial images agronomists can detect pests, weeds, nitrogen deficiencies, and other potential problems in agriculture. They can also use the system to locate cattle and their available forage over large areas, measure crop height, and generate topographic maps and models for land leveling and drainage applications.
Precision agriculture: Here to stay
Precision agriculture, and the location-based technologies upon which it is based, provides immense benefit to farmers helping them save money, increase yield, and operate more efficiently. As food production needs across the globe continue to increase, precision agriculture will be one of the key technologies farmers rely upon to help them increase productivity by maximising the use of their available land.