Litterfall is a critical link between vegetation and soils by which nutrients are returned to the soils, thus the amount and pattern of litterfall regulates nutrient cycling, soil fertility and primary productivity for most terrestrial ecosystems. We quantified, analyzed and compared macro- and micro-nutrients return through litterfall in organic and conventional cocoa agroforestry systems in Suhum, Ghana. We further assessed the contribution of shade tree species to litterfall and nutrient dynamics. The annual pattern of litterfall was affected by seasonality, with a major peak in the dry season and minor peaks during the rainy season. In terms of annual fractional litterfall, mean leaf litter from shade tree species was significantly higher (50 %) in organic systems (5.0 ± 0.5 Mg ha⁻¹ yr⁻¹) compared to conventional systems (3.3 ± 0.6 Mg ha⁻¹ yr⁻¹). Whereas cocoa leaves (45.0 %) were the predominant fraction of annual litterfall from conventional farms, both shade leaves (40.0 %) and cocoa leaves (39.4 %) dominated litterfall from organic farms. The return of primary macro-nutrients (P and K), secondary macro-nutrients (Ca, Mg and S) and micro-nutrients (Mn, B, Cu, Zn and Mo) via litterfall varied significantly with season, and annual return of nutrients were similar in organic and conventional cocoa systems. Shade tree leaf litter accounted for 30–47 % of annual macro- and micro-nutrient return (except Ni and Zn) in organic cocoa systems versus 20–35 % in conventional cocoa systems. The results emphasize the complementary role of the different shade tree species which compose organic and conventional cocoa systems in nutrient recycling. We conclude that organic management of cocoa agroforestry systems ensure nutrients return similar to those receiving synthetic fertilizer inputs, highlighting its potential to support cocoa production.

凋落物是植被和土壤之间的重要纽带，通过它使养分返回土壤，因此凋落物的数量和模式调节着大多数陆地生态系统的养分循环、土壤肥力和初级生产力。我们量化、分析和比较了加纳苏胡姆的有机和传统可可农林业系统中通过凋落物的大量和微量营养素的回报。我们进一步评估了遮荫树种对凋落物和养分动态的贡献。年度凋落物受季节影响，旱季为高峰，雨季为小高峰。就年度部分凋落物而言，有机系统中遮荫树种的平均落叶量显着更高 (50 %) (5.0 ± 0.5 Mg ha ^-1 yr ^-1) 与传统系统 (3.3 ± 0.6 Mg ha ^-1 yr ^-1）。可可叶 (45.0 %) 是传统农场每年凋落物的主要部分，而遮荫叶 (40.0 %) 和可可叶 (39.4 %) 在有机农场的凋落物中占主导地位。凋落物对初级宏量营养素（P、K）、次要宏量营养素（Ca、Mg、S）和微量营养素（Mn、B、Cu、Zn、Mo）的回报随季节变化显着，年回报有机和传统可可系统中的营养成分相似。在有机可可系统中，遮荫树叶凋落物占年度宏量和微量营养素回报（镍和锌除外）的 30-47%，而在传统可可系统中则为 20-35%。结果强调了构成有机和常规可可系统的不同遮荫树种在养分循环中的互补作用。