No abstract

Organic matter management (OMM) strategies such as farmyard manure (FYM) application, legume integration, crop residue incorporation, and alley cropping are recognized for improving soil fertility and crop productivity. However, studies on yield and economics of a combination of such strategies on smallholder farms are generally scarce, yet an understanding of such can enhance adoption. This study analyzed the yield and gross margins of crops grown with OMM strategies in comparison to those grown under inorganic fertilizer application on smallholder farms. Field experiments with five treatments over two short rainy (SR) and two long rainy (LR) seasons were conducted from January 2018 to February 2020 on 10 smallholder farms. The treatments (T) included T1 (control): the inorganic fertilizer application strategy that involved maize monocrop with 50 kg/ha Diammonium phosphate (DAP) application and the OMM strategies (T2-T5). T2: cowpea-maize-bean-maize rotation; T3: cowpea-maize-bean-maize rotation + 2.5 tons/ha FYM; T4: Faidherbia albida alleys + cowpea-maize-bean-maize rotation; and T5: Faidherbia albida alleys + cowpea-maize-bean-maize rotation + 2.5 tons/ha FYM. The maize in T3-T5 was intercropped with Mucuna pruriens. The results indicate that the grain and residue yields in LR were not significantly different among all treatments. The total variable costs, which included monetarized labor and annualized capital costs for the establishment of F. albida were significantly higher under T1 than in T2-T5 during LR2018 and not significantly different from what was observed under T3-T5 in LR2019. The accumulated revenues and gross margins for the four seasons were not significantly different between T1 and the OMM strategies. We conclude that the integration of OMM strategies can give gross margins similar to the 50 kg/ha DAP application. Further, based on the price sensitivity analysis, we conclude that the smallholder farmers could adopt T3 and T4 as the gross margins under these treatments are less affected by grain price fluctuations than in T1, T2, and T5. Since the smallholder farmers can access the planting materials, we recommend the adoption of T3 and T4 on smallholder farms.

Tackling land degradation, particularly soil erosion, remains a challenge due to the gap between science, policy, and practice which hampers the adoption of control measures by farmers. Bridging this gap requires understanding land degradation as an assemblage of the natural/biophysical and anthropogenic aspects; but also, rethinking epistemologies that level the grounds between scientists, policymakers, and farmers whose farm livelihoods are at-risk due to soil erosion. This study aimed to clarify how these requirements can be met through the lens of the recently proposed hylomorphic framework. This framework structures, in three steps, the procedure of bridging real-life experiences of farmers at risk of soil erosion with the knowledge of scientists and policymakers through the embracement of diversity in ontological realities and values, self-critiques, and coalescing overlaps in theorizations. We selected a qualitative design as most appropriate using one of the cases—the Rwenzori region—where soil erosion is high. We conducted nine focus group discussions with participants selected purposefully from three stakeholder groups including scientists, policymakers, and farmers. Following the hylomorphic framework procedure, we carried out the content analysis. Drawing on insights from this study, we elaborate on how the hylomorphic framework supports deconstructing land degradation and soil erosion, and also further offers insights into a more nature-society-inclusive soil erosion management strategy.