Abstract A numerical coupling of a dynamic biogeochemical model (B-WITCH) and a model of forest balance water (BILJOU) was used to simulate the concentration of major species within soil profiles from two contrasted ecosystems: beech and spruce stands located in the Vosges Mountains and their evolution during decades. This coupled modelling allows an important vertical discretization of water and cation cycle and a direct comparison with the hydrological and geochemical data available over twenty-five years and on a seasonal basis. The processes controlling the past evolution of soil solution chemistry have been identified and tested. The biogeochemical cycles of cations estimated on the two sites shows that the biological fluxes control up to 70% (for Ca and Mg) and up to 95% (K) of the chemical composition of the soil solutions. The Ca and Mg concentrations decrease over the last decades, which can be explained by the evolution of atmospheric inputs and by the behavior of the exchange complex. This paper highlights the weak contribution of mineral dissolution and the key role of biological recycling and cation exchange processes in the soil solution signatures. The future sustainability of forest, in mountainous environment on base poor bedrock, depends strongly on the forest management and evolution of exchangeable pool nature.

中文翻译：

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通过生物地球化学循环模型评估的过去 25 年森林集水区对过去酸沉降的响应（Strengbach，法国）

摘要 动态生物地球化学模型 (B-WITCH) 和森林平衡水模型 (BILJOU) 的数值耦合用于模拟来自两个对比生态系统的土壤剖面中主要物种的浓度：位于孚日山脉的山毛榉和云杉林分。以及他们几十年来的演变。这种耦合建模允许对水和阳离子循环进行重要的垂直离散化，并与 25 年来按季节获得的水文和地球化学数据进行直接比较。已经确定并测试了控制土壤溶液化学过去演变的过程。在两个地点估计的阳离子生物地球化学循环表明，生物通量控制了土壤溶液化学成分的 70%（Ca 和 Mg）和 95%（K）。Ca 和 Mg 浓度在过去几十年中下降，这可以通过大气输入的演变和交换复合体的行为来解释。本文强调了矿物溶解的微弱贡献以及生物循环和阳离子交换过程在土壤溶液特征中的关键作用。在基础贫瘠基岩的山区环境中，森林的未来可持续性在很大程度上取决于森林管理和可交换池性质的演变。