What is a variable application rate map?

La Orizont is a drone service provider company from Romania who passionately offers its customers the best solutions for their needs at top quality. With an enthusiastic and professional team, we help our clients with a wide range of services that can range from precision farming to 4K aerial videography and photography to 3D scans, photogrammetry and thermography. We think different, so we will customize each new project to the customer needs.

Advantages

First of all, if your drone weighs more than 500g at take off, you will need to carry out the registration steps for this drone. Registration will be requested from RCAA (Romanian Civil Aeronautical Authority) and will cost around 90 Euros plus taxes. The application will be made based on the forms on the official RCAA website.

If you don’t owe a registration certificate, you’re looking at 3 months to 1 year of imprisonment – or a fine between 20.000 and 35.000 RON).

Currently, your drone can fall into 3 categories:

Present

The agricultural sector in Romania has changed during its recent years with a good look in the following:

  • Agricultural farms work with more compact areas;

  • There were offered huge financial support from the EU for equipment and storage facilities (silos);

  • Optimal soil and weather conditions for plant production;

  • New farms establishment while upgrading the old farms with new equipment and latest technologies;

At the macroeconomic level, the share of the agricultural sector in GDP has increased significantly, leaving much room for improving productivity using the same resources. Given the current situation, increasing productivity, economic efficiency and competitiveness in agriculture is the main challenge.

Solution

Over the years, precision agriculture and drone scanning was tested outside the EU, mostly in USA and the final solution is currently applied in Romania.

The variable application rate (RAV) aims to differentiate areas of a crop fields from the plant health point of view, so that fertilizer can be applied more efficiently (not on average and based on estimations, as it is currently applied), stimulating production.

By using variable rate application maps to determine nutrient uptake capacity in a single crop field, the farmer can apply more nutrients to critical areas, average doses to medium areas, less to healthy areas, and none in technological ways or in areas where crops no longer have the capacity to absorb, consequently lowering fertilizer costs and increasing yields.

Examples

VAR Map examples:  Maps can be generated at a precision of 2 degrees, one at scale of 5 x 5 meters and another at a scale of 10 x 10 meters, according to the farmer detail needs or on the technology used.

Example 1 – 10m resolution

Ortofotoplan - RGB10m rezoluție - Zone RAV

Example 2 – 5m resolution

Ortofotoplan - RGB5m rezoluție - Zone RAV

Implementation

By using a multispectral sensor, having one multispectral sensor and one light sensor used for analyzing the vitality of plants by capturing the amount of light absorbed and reflected. This gives us ability to create absolute reflection measurements without the use of a radiometric calibration target.

The multispectral sensor captures the light and reflects it in four separate parts: green, red and 2 infrared invisible to the human eye. The light sensor which is placed on top of the drone captures the intensity of the light emitted by the sun in the four light bands sensor.

The Process

Scanarea

  • Zborul – maparea cu senzorul multispectral a suprafeței stabilite.

    Drone flight: After mounting the sensor on the top of the drone, we prepare the flight plan and check the whole process before switching to the actual flight, we are mapping the surface of the ground with the multispectral sensor, capturing thousands of informations.

  • Processing –  we process all the captured data;

    Processing the data: After the flight, we will process all the captured data in a single map that is georeferenced and contains data from all 4 multispectral sensors along with the light sensor, which helps us create a map of reflectance which is crucial in creating a variable application rate map.

  • Creating the Variable application rate map (VAR map) – it will be created a single VAR map which will be divided in zones based on the plant health variability, later to be decided how much fertilizer needs to be applied.

    Creating the Variable application rate map (VAR map) – it will be created a single VAR map which will be divided in zones (usually 3-5) based on the plant health variability, later to be decided how much fertilizer needs to be applied. This type of map can be of 2 application resolutions, one of 10m and a more detailed one of 5m.

  • Converting the variable application rate map – a map will be converted to the desired format, filling various useful informations.

    Coverting the VAR map – We can deliver a general shape file e.g. (.shp) or convert VAR maps to a format compatible with your device by uploading the following data: general information about the plant hybrid, type of fertilizer used, description of the fertilization phase, name of the load, name of the farm, name of the plot, name of the worker, the target rate and specific rate of application based on each area which could determined and uploaded in the new map format.

    .

Application

  • Variable application rate map utility – the maps will be uploaded in the equipment’s GPS system and will start work

    Variable application rate application –  The part we are all waiting for, going on the field and using all the data collected. The maps will be uploaded to the GPS tracking system of the equipment and will start working on the field. Depending on the GPS position, the equipment will recognize and will open or close the fertilizer terminal depending on the each area created. By using modern agricultural equipment that supports variable application rate maps (VAR maps),  the process can improve plant health and quality, and a substantial cost cut.

  • The results we’re tracking – all information will be recorded in a farm management software where you can track the results and make the best decisions.

Benefits and figures

Input data for analysis

SEE TABLE

Field area

As mentioned above, we concluded that we have 5 management areas in which we apply variable fertilized depending on the ability of the plant to absorb the nutrients.

SEE TABLE

Based on our database, by using variable application rate, we can achieve 17% in fertilization savings. With 4 applications we achieve gross profits of 22 Euros/hectare/season. The calculation was done as follows:

SEE TABLE

The total cost of fertilization (raw material) depends on the number of applications per season, between 23 Euros/ha and 133 Euros/ha. Compared to an average consumption of 130kg/ha, we can achieve a gross saving between 4-22 Euros/ha.

By taking into account the drone overflight and the professional services in precision agriculture, the net benefit/ha could be between 8-16 Euros/ha.

Based on the Grains Research & Development Corporation study, a VAR fertilizer application increases yield by at least 10%, which could generate additional revenue.

Addition savings and income can generate benefits of up to 117 Euros/ton, with a 12% increase in wheat production profitability.

In conclusion

Variable application rate in numbers

  • 5 Eur/Ha (-17%)  – gross savings of fertilizers/application

  • 22 Eur/Ha gross savings for full season fertilization

  • 10% Increase in production because of the variable application rate

  • 12% Increase in profitability (117 Euros/ha in benefits) for wheat production