Cork oak woodlands are highly biodiverse silvopastoral systems, economically and socially relevant to rural communities in many Mediterranean areas. The installation of legume-rich pasture mixtures became a common practice in these woodlands aiming to obtain higher productivity, to improve soil fertility, and to increase the amount of protein for forage. The predicted impacts of climate change will affect pasture productivity either by altering the biomass total amount or its seasonal productivity. We analysed an 8-years data series of meteorological variables and herbaceous biomass productivity collected in a certified cork oak ecosystem with a moderate tree density (177 trees ha⁻¹) to investigate how understorey herbaceous biomass is affected by inter annual and seasonal climate variability. The field collections were carried out in two contrasting understorey management systems: a natural understorey vegetation (NU) subject to shrub clearing every 5 years, without grazing; and a sown improved pasture, installed in 2009, grazed by cattle (IP). Results have shown that herbaceous biomass productivity was on average 8 times higher in IP than in the NU most likely due to the positive effects of the initial fertilization and the legume rich seed composition which increased N soil availability. The main climatic driver explaining the biomass productivity was the cumulative precipitation from February to May. The proportion of grasses increased in response to drought with a pronounce decrease in legumes, regardless of the management system. Nonetheless, the NU system was more resilient to drought compared to IP suggesting a need to better understand the role and contribution of each native species to resistance, resilience and recovery to drought in order to improve future forage mixtures. These results may support better management decisions by forest producers which are mostly based on empirical procedures and might provide some directions for further studies.

软木栎林地是高度生物多样性的林牧系统，在经济和社会方面与许多地中海地区的农村社区相关。在这些林地中安装富含豆科植物的草场混合物已成为一种常见做法，旨在获得更高的生产力，提高土壤肥力，并增加草料的蛋白质含量。气候变化的预测影响将通过改变生物量总量或其季节性生产力来影响牧场生产力。我们分析了在经过认证的软木橡木生态系统中收集的 8 年气象变量和草本生物量的数据系列，树木密度适中（177 棵树 ha ^-1) 研究下层草本生物量如何受到年际和季节气候变化的影响。野外采集是在两个对比鲜明的林下管理系统中进行的：自然林下植被 (NU)，每 5 年清除一次灌木，不放牧；和一个播种的改良牧场，于 2009 年安装，由牛 (IP) 放牧。结果表明，IP 中的草本生物量生产力平均比 NU 高 8 倍，这很可能是由于初始施肥和富含豆类的种子成分的积极影响，这增加了 N 土壤的可用性。解释生物量生产力的主要气候驱动因素是 2 月至 5 月的累积降水。草的比例因干旱而增加，豆类明显减少，与管理系统无关。尽管如此，与 IP 相比，NU 系统对干旱的抵抗力更强，这表明需要更好地了解每个本地物种对干旱的抗性、恢复力和恢复的作用和贡献，以改善未来的草料混合物。这些结果可能支持主要基于经验程序的森林生产者更好的管理决策，并可能为进一步研究提供一些方向。