THE CHALLENGES
Agriculture is an integral part of the Mozambican economy, with over 80% of the population employed in this sector, the majority being classified as Smallholder Farmers. The average cultivated area is about 0.2 hectares per household. Farmers often operate individually and in the so called informal economy. Although smallholder farmers are responsible for much of the country's food supply, little is known about the production systems used. Questions such as how much land is irrigated, and where cannot be answered at this moment. Insight in irrigation practices is essential to; understand and manage the total freshwater balance; and to understand the corresponding crop growth processes and yield. Resilience BV in partnership with Delft University of technology would like to build its capacity to use remote sensing for detection of irrigated agriculture to identify the total area covered by irrigated agriculture, what crops are grown and how much water is used.
THE SOLUTION
Remote sensing, obtaining information without physically assessing the object of research, offers many possibilities. This research project examines the potential of using Sentinel-1 for irrigation detection. Sentinel-1 is a radar satellite, which can gather information about the earth's surface with an accuracy of 10x10 meters and revisits each place on earth every 12 days. The satellite actively emits waves and can obtain information from the reflected signal. In contrast to optical satellites that depend on the sun's radiation, this satellite has the advantage of being able to obtain information in all weather conditions, and even at night. Sentinel-1 data is susceptible to the amount of water in the soil, and the density of vegetation. This research project investigates whether these radar data can provide a better identification of irrigated (and non-irrigated) farmland compared with the only visible bands (Sentinel-2), and tries to identify the quantity the crops.
THE IMPACT
Besides detecting different agricultural practices, Sentinel-1 can provide additional inisghtfull information. On a large scale and systematic way, it can give insight into the amount of water used in agriculture and monitor the growth process and yield of different crops. Having more insight in irrigated smallholder agriculture can be used for policy and to improve service delivery to farmers to counter the challenges facing them.
For question and suggestions, feel free to contact Floor Crispijn (MSc thesis at Delft University of Technology – f.m.crispijn@student.tudelft.nl
Picture: The real image shows pivot agriculture in Mozambique. The coloured image provides radar data of the soil moisture of these agricultural plots. Different colours show different intensities of irrigation and soil moisture.