Shifting weather patterns as a result of climate change are threatening food production globally, with Africa being very vulnerable.
Tharaka, a semi-arid region in Tharaka-Nithi County, has not been spared. Weather variabilities have caused wide fluctuations in agricultural production, taking a toll on farmers, especially those relying on rain-fed agriculture.
This situation prompted scientists from Meru University of Science and Technology to employ two technologies — a sensor-based irrigation system and biochar, a soil amendment product — in Tharaka to enhance farmers’ resilience.
According to Mr Daniel Maiteithia, the lead scientist, “climate change has rendered a majority of farmers to be a very vulnerable group, necessitating the need for appropriate mitigation and adaptive measures that will equip farmers with some coping strategies to climate hazards.”
In assisting smallholder farmers establish conservation agriculture and increase productivity, the university embarked on an initiative that was funded by the government under the Kenya Climate Smart Agricultural Project.
Thirty farmers were directly supported to fully install the system that costs approximately Sh300,000. This includes the cost of installing the drip kits on a quarter acre piece of land, acquisition of a solar-powered water pump and the electronic control system.
The solar-powered sensor-based irrigation system periodically monitors the water content in the soil, relaying the information to the programmed electronic control that prompts watering of crops.
“The programmed electronic control unit periodically monitors the water content present in the soil, and the information is used to automatically trigger watering of crops. Predetermined thresholds of moisture content in the soil are used to determine whether the system should supply water to crops or shut the supply,” Mr Maiteithia explains.
The irrigation unit comprises a solar-power supply unit for powering the electronic and electrical appliances, a programmed electronic control unit which serves as the brain of the system, soil moisture sensors for measuring the soil water content in the irrigated fields and a panel of electronically controlled water distribution channels.
The entire system is packaged in a wheelbarrow for ease of mobility within the farm.
The water source can either be an elevated water storage tank, a borehole, harvested rain water in an earth dam or a nearby river or lake, where the piped water flows by gravity.
Once the water is dispensed from the water distribution channels, it is then conveyed by pipes to portions of land with crops under irrigation. The water can then be administered to crops using drip tapes, sprinkler or even furrow.
Drip irrigation is, however, the preferred method due to its high crop water use efficiency as it uses less water to irrigate crops.
In order to make the climate smart irrigation technology more effective, the scientists came up with a tailored technology for the region that enables farmers to benefit from a shared irrigation technology — E-pivot.
The E-pivot is a devised model in which a single unit can be shared by farmers living within a common neighbourhood. To enable easy mobility of the system from one farmer’s field to the next, the scientists packaged the irrigation system into a three-wheeled motorbike, commonly referred to as a tuk-tuk.
“The soil moisture monitoring sensors are installed at farmers’ fields and they wirelessly log real-time data of the soil moisture in a cloud-based database. The cloud server also implements a service that determines which farm requires watering and sends an alert message to a tuk-tuk operator to pump water to that respective farm,” Mr Maiteithia explains.
The technology thus ensures efficiency in water application, resulting in improved crop yields, minimal water wastage and reduced labour cost.
The system is designed in such a manner that it requires minimal technical skills.
With the technology, farmers can also harness solar energy for lighting and powering small electrical appliances.
Farmers can also use it to cultivate high value crops.
To make the project more sustainable, especially for smallholder farmers, the project recommends other financial institutions to tailor-make financial products that would enable small-scale farmers access the irrigation technology.
“We are also developing a unique financing model that will enable more farmers to access the technology on leasehold basis. Under this model, we will be renting out the technology to farmers and charging them on the basis of usage. For instance, if a farmer has leased a solar-powered irrigation system, we would apply a levy fee depending on the amount of water dispensed by the system to his/her crops,” Mr Maiteithia says.
To also make the project a success, the team worked with the Tharaka-Nithi government, with the county extension officers assisting in training and mobilisation of farmers.
For the biochar technology, the technology entails burning of plant biomass under limited oxygen concentration. The product is then applied to soils before planting crops.
Prof Peter Masinde from Meru University explains that the technology helps in improving soil health, a factor that enhances the soil’s capacity to retain soil moisture while attracting beneficial micro-organisms.
“It can also improve soil aeration as well as regulate soil pH. Consequently, the soil is able to better support plant growth and produce more crop yields,” he says.
Mr Stephen Mathenge, a beneficiary, says since the implementation of the technology, he has managed to farm high value crops like onions, tomatoes and water melon.
Though a success, the project encountered some hiccups including financial challenges, increased prices and cumbersome procurement processes applied by public institutions leading to delay in acquisition of project materials.
“One good thing with the technology is that it can easily be replicated in other regions even within the East Africa Community because farming communities face similar challenges and are eagerly waiting for solutions,” Mr Maiteithia says.
“We also recommend establishment of water pipelines that route water from the reservoir to the farmers’ fields. A levy can then be applied for supply of water to the irrigated fields based on the quantity of water supplied to each farmer,” he adds.