Forage cultivation plays a pivotal role in sustaining ruminants in resource-limited ecosystems such as the hot-summer Mediterranean agroforestry systems of the Iberian Peninsula comprising oak trees (Quercus spp.) and grassland species. Intercropping techniques can enhance forage yields and nutritional quality.

This study assessed the yield and nutritional quality of organic forage mixtures in an Iberian oak grassland ecosystem.

Six forage associations were assessed over two growing seasons: vetch (Vicia sativa L.)–triticale (Triticum × Secale), vetch–rye (Secale cereale), vetch–oat (Avena sativa), pea (Pisum sativum L.)–triticale, pea–rye, and pea–oat. The data were analysed using a multivariate procedure.

Differences in forage composition influenced nutritional quality but not yield. Vetch-based associations exhibited higher crude protein, calcium, phosphorus, potassium, zinc, magnesium, manganese and sulfur contents, along with lower proportions of neutral-detergent fibre and ether extract. The vetch–oat mixture emerged as the highest quality association. Interannual variations in precipitation and temperature caused differences in forage yield, with greater values observed in 2020 than in 2019. Forage associations also had significantly higher nutritional quality in 2020 (increased protein and mineral content, and decreased neutral detergent fibre and lignin).

All forages demonstrated satisfactory performance and quality, even in the drier conditions of 2019, suggesting high resilience and adaptability to hot-summer Mediterranean oak grassland ecosystems.

The findings of this study are relevant for organic farmers in resource-limited ecosystems. This information empowers them to select the most suitable forage species based on the specific agroclimatic conditions of each growing season.

饲料种植在维持资源有限的生态系统中的反刍动物方面发挥着关键作用，例如由橡树（栎属）和草原物种组成的伊比利亚半岛夏季炎热的地中海农林复合系统。间作技术可以提高饲料产量和营养质量。

这项研究评估了伊比利亚橡树草原生态系统中有机饲料混合物的产量和营养质量。

在两个生长季节评估了六种饲料关联：野豌豆（Vicia sativa L.）-小黑麦（Triticum  ×  Secale）、野豌豆-黑麦（Secaleale）、野豌豆-燕麦（Avena sativa）、豌豆（Pisum sativum L.）-小黑麦、豌豆黑麦和豌豆燕麦。使用多变量程序分析数据。

饲料成分的差异影响营养品质，但不影响产量。以野豌豆为基础的组合表现出较高的粗蛋白、钙、磷、钾、锌、镁、锰和硫含量，以及较低比例的中性洗涤剂纤维和乙醚提取物。野豌豆和燕麦的混合物成为最高品质的组合。降水量和温度的年际变化导致了牧草产量的差异，2020年观察到的值比2019年更大。2020年牧草协会的营养质量也显着提高（蛋白质和矿物质含量增加，中性洗涤纤维和木质素减少）。

即使在 2019 年干燥的条件下，所有牧草都表现出令人满意的性能和质量，这表明地中海橡树草原生态系统具有高恢复力和适应性。

这项研究的结果与资源有限的生态系统中的有机农民相关。这些信息使他们能够根据每个生长季节的具体农业气候条件选择最合适的饲料品种。