Across Africa, poor soils and widespread soil degradation are limiting growth in agricultural production and threatening the viability of food systems. Yet healthy soils are vital to maintaining food security, whole-farm productivity and smallholder incomes.
Healthy soils contribute towards improved livelihoods and national economic growth, while building resilience to climate change. In addition, carbon sequestration in soils can contribute to climate change mitigation.
To help farmers and other decision makers beat challenges posed by both climate change and land degradation, game-changing tools and technologies are needed. Decision-support tools need to empower farming communities towards better livelihoods, by saving on labor demands, increasing the adaptive capacity of farmers and by buffering them against extreme weather conditions.
Researchers at CIAT are engaged in new research aimed at supporting smallholder farmers to make decisions based on strategic land health information. This information service being developed makes use of recent advances in satellite and computing technologies, supporting farmers to make decisions related to irrigation, fertilizer application and yield prediction.
These tools support sustainable land and water management, enabling smallholder farmers to identify field management options, and even transcending farmers to equip policy makers and implementing agencies with targeted land, soil and water management options.
Satellite data for smallholder farmers
Dubbed the Smart Agricultural Resource Optimization System, or SAROS, the system uses satellite radar imagery from the EU’s Copernicus program to get regular snapshots of the land and detect soil conditions over an area.
It also uses computerized solar powered field units that continuously monitor the environment and relay data to a server via GSM networks. The field units collect data to calibrate the satellite imagery and derive accurate land characteristics. The data are all processed and turned into actionable information: such as soil water requirements or crop water stress over an area.
This information is then communicated to farmers through an intuitive mobile-based platform, allowing major decisions on soil, water and crop management based on scientific fact.
The application can be installed in a mobile phone and used to access the decision support tool. This mobile delivery concept has been shown to work well with services such as the LandPKS tools already using mobile phones to provide climate and soil information to farmers in Sub-Saharan Africa. SAROS will present its information in the form of simple thematic maps that can be read visually by all persons regardless of technical skills.
Smallholder farmers regularly make decisions about how much water and fertilizer to use on their farm, and when. But these decisions are not always scientifically grounded, being based either on common practice or intuition.
This translates into low efficiency in utilization of scarce agricultural resources such as water. For example, studies show that small-scale farmers lose half of the water they apply on their fields due to irrigation inefficiency – situation that is of concern particularly in arid and semi-arid countries.
If for example, farmers knew when to irrigate and in which areas of their farm water is needed, less water would be required for crop production. This would increase the sustainability of water resources within communities faced with rainfall variability and who need to rely on limited water sources for irrigation. The same logic applies to other essential agricultural inputs where there is enough room for improvement in efficiency.
The SAROS service is being developed to provide farmers with real time information about the soil moisture content on their fields among other parameters. This will support decisions around irrigation allowing the prioritization of certain areas on a field based on water need.
The service will provide information to farmers when their crops are not receiving enough water or are stressed, supporting various other decisions. The ultimate goal is to enable smallholder farmers to increase their efficiency and bolster their resilience.
Saving water, reducing labor
But decision support is only half the ability of the new tool. The SAROS system can also be configured to control automated irrigation through a “field unit|, which collects field data and controls the opening and closing of irrigation valves.
This ensures water is released only when needed and to those areas most required. Since irrigation is based on continuous monitoring of soil moisture conditions, it is very efficient compared to manual irrigation and also offers vast labor and time savings.
We expect that for those farmers who have already invested in irrigation systems, inclusion of the SAROS field unit to control the irrigation will translate into significant savings in several ways, but they won’t need the units to have access to other information through the tool.
As the world faces up to the challenges of climate change, rainfall variability and water scarcity, decision support and optimization technologies such as the SAROS will play an increasingly pivotal role in agricultural systems. Work on the SAROS is ongoing, with the system being developed and tested in CIAT research sites in Tanzania.