The soils of Mediterranean semiarid environments are commonly characterized by low levels of organic matter and mineral elements, as well as severe weed infestations, which, taken together, cause an intensive use of auxiliary inputs (tillage, fertilizers, herbicides). Although cover crops are recognized to sustainably improve soil health, the impact of Trifolium subterraneum L. cover cropping needs specific attention. This research investigates for the first time the effects over 4 years of T. subterraneum and spontaneous flora cover crops, after either incorporating their dead mulches into the soil or leaving them on the soil surface, on soil organic matter (SOM), macroelements, mineral nitrogen, microelements, and weed seedbank dynamics as indicators of soil quality in an apricot orchard. Compared to a conventional management control, the T. subterraneum cover crop with the burying of dead mulch into the soil increased the amount of SOM (+ 15%), ammoniacal (+ 194%) and nitric (+ 308%) nitrogen, assimilable P₂O₅ (+ 5%), exchangeable K₂O (+ 14%), exchangeable Na (+ 32%), exchangeable K (+ 16%), Fe (+ 15%), Mn (+ 28%), Zn (+ 36%), and Cu (+ 24%), while it decreased the weed seedbank size (‒ 54%) and enhanced weed biodiversity. These findings suggest that T. subterraneum cover cropping may be an environment-friendly tool to enhance soil quality and limit auxiliary input supply in Mediterranean orchards.

地中海半干旱环境的土壤通常以有机质和矿物元素含量低以及杂草严重侵扰为特征，综合起来，导致大量使用辅助投入物（耕作、化肥、除草剂）。尽管人们认为覆盖作物可以持续改善土壤健康，但需要特别注意Trifolium subterraneum L. 覆盖作物的影响。这项研究首次调查了T. subterraneum 4 年的影响和自发植物群覆盖作物，在将它们的死覆盖物掺入土壤或将它们留在土壤表面后，土壤有机质 (SOM)、常量元素、矿物氮、微量元素和杂草种子库动态作为杏土壤质量的指标果园。与常规管理控制相比，将死覆盖物埋入土壤中的T. subterraneum覆盖作物增加了 SOM (+ 15%)、氨性 (+ 194%) 和硝酸 (+ 308%) 氮、可同化 P ₂ O ₅ (+ 5%)，可交换 K ₂O (+ 14%)、可交换 Na (+ 32%)、可交换 K (+ 16%)、Fe (+ 15%)、Mn (+ 28%)、Zn (+ 36%) 和 Cu (+ 24%) )，同时它减少了杂草种子库的大小 (‒ 54%) 并增强了杂草的生物多样性。这些发现表明，T. subterraneum覆盖种植可能是一种环境友好的工具，可提高地中海果园的土壤质量并限制辅助投入供应。