A combination of resilient practices maximizes productivity and water, carbon, and nutrient stocks in forage species systems in the Brazilian semi-arid region

Abstract Adopting resilient practices is crucial to balancing food production and crop sustainability in semiarid regions. Therefore, adopting systems that provide greater stocks of water, carbon, and nutrients at the soil-plant interface is crucial. The objective of this study was to assess water, carbon, and nutrient stocks in the soil-plant systems of irrigated forage crops in the semiarid region of Brazil. The study was conducted in Serra Talhada, Pernambuco, Brazil. Four production cycles were evaluated between January 2017 and January 2022, comprising seven cropping systems: pigeon pea (S1), millet (S2), sorghum (S3), cactus forage (S4), cactus forage-sunflower-pigeon pea (S5), cactus forage-sorghum-millet (S6), and cactus forage-sorghum (S7). The following parameters were evaluated: fresh matter (FM) and dry matter (DM) productivity, as well as water, organic carbon (OC), and nutrient (N, P, K + , Ca 2+ , Mg 2+ , and Na + ) stocks in the plant and soil at depths of 0–20 and 20–40 cm. The intercropping systems presented the highest mean values for each of the plant variables. Among the single systems, forage cactus did not differ from the intercropped systems for FM, plant stocks of P, Ca 2+ , Mg 2+ , and water. The single sorghum presented higher values for plant DM (44.0 Mg ha −1 ) and plant OC (18.7 Mg ha −1 ). For soil variables, only the levels of P, K + , Na +, and OC showed significant differences ( p < 0.05). The single forage cactus had the highest average soil OC value (14.5 Mg ha −1 ). The cactus-sorghum intercrop system appears to offer the best balance between productivity and water, OC, and nutrient reserves. Among the isolated systems, forage cactus stores the largest amounts of OC in the soil, while sorghum stands out for accumulating carbon in the plants. Studies on the sustainability of forage species should be encouraged to improve the development of agricultural systems.