Improving Farmers’ Profitability, Soil and Water Conservation through an Adapted Tillage Technique: Experiences from the Cultivation of Potatoes in Bamiléké’s Hills, Cameroon

On farms situated on slopes, such as those in the Western Highlands of Cameroon, the implementation of soil and water conservation techniques remains a major concern. The land preparation methods commonly practiced in the Western Highlands agro-ecological zone of Cameroon are ridging along the steepest slopes (RASS) and the flatbed (FB). Field observations showed FB and RASS promote erosion by runoff, thereby compromising some agriculture functions (environmental function, production function and even social function). In order to ensure soil stability and maintain good water quality for rivers, a new land preparation method, tied ridging (TR), was tested. Erosion by runoff tests were conducted with four blocks of three plots on each of the most commonly exploited slopes, namely 11% and 29% gradient. With the main crop in the area (potato, Solanum tuberosum L.), the performance of RASS, FB, and TR were compared during crop years 2013 and 2014. The water runoff and sediments were collected per plot and per block after every rainfall. The results showed a significant difference between the FB or RASS and TR in terms of soil loss (Fmin(2, 2) = 322.7, p = 0.003), yields (F(2, 2) = 287.7, p = 0.003), and runoff water (Fmin(2, 12) = 2.4x106, p < 0.001). The TR technique generated a 7% increase in seedlings density, a 41% increase in the workforce, and an 81% and 100% increase in yields compared to FB in 11% and 29% slopes, respectively. The TR increased farmer’s profitability by 686 US$.ha-1 and 1420 US$.ha-1 over RASS in 11% and 29% slopes, respectively. The TR showed undeniable advantages: for the producer, the stress of additional work was offset by the gain in yields while creating additional job opportunities and improving the conservation of soil and water. Although the technique has several advantages, the provision of financial means for its implementation could be a negative point. Twelve farmers were involved in the experiment. The test results convinced the participants and other curious farmers who adopted the technology during the second experiment.