Agricultural intensification reduces the taxonomic diversity of bird communities, but its influence on functional diversity has been less studied. Here, we analyze the response of functional diversity of different cereal farmland bird communities across Europe to a gradient of agricultural intensification. We collected bibliographical information on life history traits (i.e. body mass, brain size, age of sexual maturity, clutch size, number of clutches, lifespan) of 30 species of birds recorded during field surveys in eight European countries. The index "brood value" was calculated to know each species’ level of reproductive investment per clutch. Intensification gradients at two spatial scales were obtained from field data through PCA, related to management practices at the field scale and the variation in structure and composition of farmland at the landscape scale respectively. We calculated the functional diversity index (FD) and the community-weighted mean (CWM) for each trait and sampling area, and linear mixed models in relation to the two intensification gradients were performed. Results showed that stronger intensification at the field level favors the assembly of shorter-lived communities and bird species with smaller relative brain sizes, also decreasing overall trait diversity. It also restricts the range of strategies for parental investment, reducing the functional diversity of the brood value index. More intensive field management would favor bird communities dominated by generalist and even introduced and/or managed hunting species, while putting at risk those farmland- and grassland-adapted species, typically more associated with the provision of ecosystem services. This highlights the relevance of field management (agrochemicals use, ploughing frequency) for the functional composition of bird communities and the conservation of farmland biodiversity. These findings add to existing knowledge on how species’ pace of life and cognitive capacity interact with drivers of global change, such as agricultural intensification.

农业集约化降低了鸟类群落的分类多样性，但其对功能多样性的影响研究较少。在这里，我们分析了欧洲不同谷物农田鸟类群落的功能多样性对农业集约化梯度的响应。我们收集了在 8 个欧洲国家进行实地调查时记录的 30 种鸟类的生活史特征（即体重、大脑大小、性成熟年龄、窝数、窝数、寿命）的文献信息。计算指数“育雏价值”以了解每个物种每窝繁殖投资的水平。通过PCA从田间数据获得两个空间尺度的集约化梯度，分别与田间尺度的管理实践和景观尺度的农田结构和组成的变化有关。我们计算了每个性状和采样区域的功能多样性指数（FD）和群落加权平均值（CWM），并执行了与两个强化梯度相关的线性混合模型。结果表明，在野外水平上更强的集约化有利于寿命较短的群落和相对大脑尺寸较小的鸟类的聚集，同时也降低了总体性状多样性。它还限制了亲代投资策略的范围，减少了育雏价值指数的功能多样性。更集约的实地管理将有利于以通才甚至引进和/或管理的狩猎物种为主的鸟类群落，同时使那些适应农田和草原的物种面临风险，这些物种通常与提供生态系统服务更相关。这凸显了田间管理（农用化学品的使用、耕作频率）与鸟类群落功能构成和农田生物多样性保护的相关性。这些发现丰富了关于物种的生活节奏和认知能力如何与农业集约化等全球变化驱动因素相互作用的现有知识。