Herviyanti, An Nisa Mutiara Fathi, Irwan Darfis, M. Hafizh Ash Shiddiq, Defry Jonica Putri, Amsar Maulana, Ridho Ryswaldi
Low soil surface charge and nutrient imbalances in Inceptisols threaten horticultural productivity in monoculture and polyculture systems. Ethno-agronomy management using local resources is expected to be a solution to these issues. The research aims to assess the effects of Nagari local ameliorant resource formulations (LARFs; bamboo biochar (BB), Tithonia green fertilizer (TGF), chicken manure (CM), and Agam compost (CA)) on surface charge and nutrients. A randomized complete block design (RCBD) was used to test 5 treatments: Control, LARF-I (BB + TGF + CM), LARF-II (BB + TGF + CA), conventional farming (CF), and Ministry of Agriculture Recommendations (MAR), with 3 replications, in Banuhampu, Agam. LARFs significantly improved soil surface charge properties (pH H2O, electrical conductivity (EC), percentage of organic matter (%OM), and cation exchange capacity (CEC)) and macronutrient levels (organic C (OC), total N, available P, and exchangeable K) compared with the control and conventional farming. LARF-I excelled in pH H2O, EC, %OM, and CEC under monoculture (+16–170%) and polyculture (+23–92%), outperforming CF by 11–157%. LARF-II led in OC (+91–112%) and total N (+37–441%), while LARF-I dominated available P (+122–328%) and exchangeable K (+60–78%). These enhancements increased crop nutrient uptake (N, P, and K) by up to 170% in string bean (monoculture) and broccoli (polyculture), with LARF-I achieving the highest overall increase. Yields increased most under LARF-II (string bean +33%, broccoli +74%, lettuce +70% compared to the control; 31–43% above CF), followed closely by LARF-I (+29–65% from the control; 21–29% above CF). These improvements enhanced soil fertility and nutrient availability, supporting better nutrient uptake and crop performance. LARFs promote sustainable restoration of soil fertility and support ethno-agronomic practices in horticulture. © 2026 Universitas Sebelas Maret.
Department of Soil Science and Land Resources, Faculty of Agriculture, Universitas Andalas, Padang, Indonesia; Post-Doctoral Program of Faculty of Agriculture, Universitas Andalas, Padang, Indonesia; Department of Management, Faculty of Economy and Business, Universitas Negeri Padang, Padang, Indonesia
