Abstract Mixed-species forests have become widely studied in the recent years because of their potential to mitigate risks associated with climate change. However, their growth dynamics are often difficult to predict because species interactions vary with climatic and edaphic conditions, stand structure and forest management. We examined species interactions in mixtures of Scots pine (Pinus sylvestris) and pedunculate oak (Quercus robur) under climate change and for varying soil conditions in the Netherlands, over a period of 30 years. We parameterized, calibrated and validated the 3-PGmix model for mixing effects in Scots pine and oak mixtures and analysed these effects under climate change. 3-PGmix performed well for the variety of forest stands examined throughout the Netherlands. Furthermore, it was also able to reproduce mixing effects for each species in mixtures compared to monocultures for the growing conditions examined. Simulated climate change resulted in lower productivity of oak and higher productivity of Scots pine, compared to the current climate. This was observed for both monospecific stands and mixtures. The mixture of Scots pine and oak showed clear but limited overyielding (mixture yield greater than the mean of the monocultures), which was mainly attributed to oak. This was maintained under the most extreme climate scenario for 2050, implying that for oak, increased growth due to mixing with Scots pine was larger than the reduction in productivity under the future climate. On resource-limited soils, Scots pine competitiveness was increased, and this was maintained under a warmer and drier climate. Our results suggest that projected changes in climate will influence species interactions and result in increased Scots pine productivity, notably on poor sandy soils, which are typical of the Netherlands.

中文翻译：

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气候变化下苏格兰松和有花序橡树混交林的物种相互作用

摘要 近年来，混交林因其具有减轻气候变化相关风险的潜力而得到广泛研究。然而，它们的生长动态通常难以预测，因为物种相互作用因气候和土壤条件、林分结构和森林管理而异。我们研究了苏格兰松（Pinus sylvestris）和有花序橡树（Quercus robur）混合物在气候变化和荷兰不同土壤条件下的 30 年间的物种相互作用。我们参数化、校准和验证了 3-PGmix 模型在苏格兰松树和橡木混合物中的混合效应，并分析了气候变化下的这些效应。3-PGmix 在整个荷兰检查的各种林分中表现良好。此外，与所检查的生长条件下的单一栽培相比，它还能够重现混合物中每个物种的混合效应。与当前气候相比，模拟的气候变化导致橡木的生产力降低，而苏格兰松的生产力更高。这对于单特异性支架和混合物均观察到。苏格兰松树和橡树的混合物显示出明显但有限的超产（混合物产量大于单一栽培的平均值），这主要归因于橡木。这在 2050 年最极端的气候情景下保持不变，这意味着对于橡木而言，由于与苏格兰松混合而导致的生长增加大于未来气候下生产力的降低。在资源有限的土壤上，苏格兰松树的竞争力得到了提高，并且在温暖干燥的气候下得以保持。