Conservation agriculture is helping farmers adapt to climate change: lessons from southern Africa
This article is a summary of Christian Thierfelder’s presentation at the Climate Resilient Agriculture Success Stories webinar, which was organized by The Food, Agriculture and Natural Resources Policy Analysis Network (FANRPAN) on 28 November 2019.
Projections show that the impact of climate change by 2080 across the world will be devastating. In areas such as southern Africa where the Africa Research in Sustainable Intensification for the Next Generation (Africa RISING) program is partnering with the International Maize and Wheat Improvement Center (CIMMYT) to scale out climate-smart agriculture (CSA) practices, the effects are predicted to be dire with crop yields projected to decline by between 15–50% if no adaptation measures are taken.
Southern Africa is characterized by subhumid to semi-arid conditions and crops such as cereals grown in these areas are exposed to vulnerable climate conditions such as drought and erosion. In this region, one of the goals of Africa RISING is to enhance food and livestock production under climate variability. The project is working with communities that face climate vulnerability in Malawi and Zambia to establish climate-resilient interventions. These interventions bring together various stakeholders from the national research systems, extension, private sector partners as well as non-governmental organizations representing a broad coalition of players unified by the goal of ensuring smallholders are equipped to cope with the effects of climate change.
Promoting and scaling conservation agriculture (CA) practices is a key aspect of the CSA practices being advanced by the project. CA is a cropping system made of different practices including no-till farming, crop residue retention as mulch and crop rotations. In Malawi, CA is complemented by targeted fertilizer applications, the use of drought-tolerant cultivars, and doubled-up legume systems of pigeon peas and groundnuts.
Conservation agriculture interventions have been trialed for 15 years and have proven a significant impact on cereal and legume production in the country. In an assessment comparing maize productivity in farms under CA versus those under conventional tillage, it was noted that CA resulted in 75% higher yield compared to conventional tillage, reduced farm labour (allowing farmers to use time gained for other pressing activities), greater economic benefits in form of a higher net benefit and net present value, as well as higher returns to labour and investment.
Another huge success of CA is its ability to significantly reduce soil erosion and surface run, improve infiltration and available soil moisture while gradually improving soil carbon. Practicing CA means 84–90 tonne per hectare less erosion over a 15 year period than under conventional tillage systems, which leads to higher soil fertility and sustainability.
‘To practice CA, a farmer requires simple tools such as a pointed stick (dibble stick) or animal traction rip line or direct seeding tools. It can be adapted to the different farming systems and is flexible in the way it is applied to rotations of maize with soybeans, groundnuts, cowpeas and even agroforestry species such as Gliricidia,’ explains Christian Thierfelder, CIMMYT’s principal cropping systems agronomist and project leader.
Despite conservation agriculture being highly beneficial, its adoption is still slow in many parts of Africa. Factors such as agronomic challenges (e.g. failure to obtain/retain enough crop residues for surface cover, weed control and maize monocropping), lack of appropriate markets for legume crops, cultural beliefs and norms and lack of an enabling environment to scale the system have hampered its widespread adoption.
‘Enough evidence of the advantages of CA has been generated and we are now working to take this to a wider level targeting millions of farmers across Africa in the next five years to address the urgent need to adapt to a changing climate while maintaining sustainability,’ says Thierfelder.