By Jorge Torres-León, José Monsalve, Cristian Angarita from Cenipalma
Over the past few decades, huge growth has been shown in geospatial technology applications in different fields worldwide. As for projects in agriculture, there has been a considerable increase in the use of images provided to us by earth observation satellites. These images allow us to obtain a top-down view of very large areas, to analyse the terrain, and to have better data for decision making.
Like all technology, the use of satellite images has both advantages and disadvantages. Although it is possible to have good quality images of almost any location on the planet, its most noticeable disadvantage is that since the sensor is inside a satellite orbiting at very high altitudes, it captures the clouds, thus creating a ‘mask’ above the objects requiring observation. Colombia, being in a tropical area, has a very high density of clouds most of the time, making this a frequent difficulty.
This is where we find the importance and efficiency of using other technology, namely unmanned aerial vehicles (UAVs or drones), since they operate at lower altitudes. As regulated by the Colombian Aeronautics Authority, all UAV flights that we conduct are below 150m and thus drones flying over oil palm crops are able to capture very high resolution images free of clouds.
Drone flights support farmers with decision making
Equipped with multispectral and thermal sensors, our UAVs have collected images in oil palm plantations in different areas of Colombia. Regular flights means that the EcoProMIS project is able to achieve continuous monitoring and comparison of the development of the plants. Different phenological (growth) stages of the crop are observed, including the unproductive, stabilisation, and productive phases.
Through multispectral images, such as those seen below, it is possible to perform calculations using the spectral bands being captured by the sensors. One approach we use is the vegetation index, in which it is possible to remotely detect the status of individual plants in terms of growth, pest infestation, water stress, flooded areas, nutritional deficiencies, systemic diseases, etc.
For the agricultural sector, this type of information is extremely important. The EcoProMIS platform sends such information directly to the grower’s mobile phone, and this near real time data allows farmers to take preventive measures to support crop performance.
Another technique we use is with images acquired by the thermal sensor on the drones, which provide information on the temperature of each of the surfaces within the study area. Using this technology, a farmer can pinpoint problems associated with disease and water stress. The acquisition of spectral images can be scheduled on a daily basis to quickly identify and quantify unhealthy plants, such as those suffering from chlorosis. Early identification allows farmers to make decisions in a timely manner so as to protect their crops and yields.
Connected weather stations
Digitally-connected weather stations are another form of high-tech equipment being used by the EcoProMIS project to support farmers. These have been installed in experimental plots and offer the advantage of knowing in real time the climatic conditions such as rain, temperature, humidity, etc.
It is essential to combine data collected by the weather stations with the data from drone images and oil palm models, as almost 70% of the crop performance can be explained by the surrounding climatic conditions.
Greenhouse gas data
Currently, our project collects GHG data through eddy covariance towers in two different palm regions in the country. This system allows us to quantify the CO2 (carbon dioxide) that is absorbed by the oil palm during its photosynthetic process as well as the emissions of greenhouse gases such as CO2, methane and even water vapor. Through these measurements it is also possible to calculate in detail the evaporation of the ecosystem.
These high-tech systems allow more precise readings of environmental variables, such as relative humidity, atmospheric temperature, direction and wind speed, precipitation, etc. All these variables are of critical importance in establishing the influence of weather conditions on the development of oil palm cultivation as well as the effect the crop itself has on the environment.
By combining the data from satellites, drones, weather stations, and GHG towers we have a rich and detailed understanding of each farm. When this data is turned into knowledge services (such as yield-prediction) and delivered through a mobile dashboard, growers are supported so that they can make rapid and intelligent decisions in their farm management.
As we at Cenipalma work together with the other project partners in Colombia (CIAT, Fedearroz, IWCO, Solidaridad) and in the UK (Agricompas, Pixalytics) we are contributing to a high-tech digital platform that will be a great ally to oil palm cultivation.