Soybean yield gap in integrated crop-forest, conventional, and no-tillage systems in sandy soil

Abstract

Sustainable agriculture is essential for increasing land use and food security by reducing the yield gap. This study quantified yield gap components in integrated crop-forest (ICF), no-tillage (NT), and conventional tillage (CT) systems of soybean cultivated during the 2021/2022 and 2022/2023 growing seasons, in soil with 84 % of sand, over a degraded pastureland. The actual yield, leaf nutrients, soil properties, potential and attainable yields were estimated. The potential yield averaged 10,560 kg ha-¹, whereas the attainable yield reached 6,401 kg ha-¹ for NT. The actual yield averaged 5,065 kg ha-¹ in NT, 4,394 kg ha-¹ in ICF and 1,958 kg ha-¹ in CT. The agricultural efficiency reached 80 % in NT, 70 % in ICF, and 32 % in CT. In ICF, the total yield gap was 44 % (agricultural management - 20 %; land allocation to trees - 14 %; interspecific competition - 10 %). The climate efficiency ranged from 45 %, in 2021/2022, under severe water deficit, to 81 %, in 2022/2023, under a better rainfall distribution. The water availability was the main factor driving the seasonal yield variability, with NT being the most efficient system, whereas ICF showed an intermediate performance, but with both improving the soil quality. ICF achieved an agricultural efficiency comparable to the national average for soybean, demonstrating its potential to a sustainable grain and wood production in sandy soil.

KEYWORDS: Soil management, climate variability, degraded pastureland.