Anthropogenic modifications to water regimes are one of the main factors threatening the stability and existence of floodplain forests. This study presents an analysis of topsoil biogeochemistry within three floodplain forest stands with different levels of human alteration. Decreasing contents of soil organic carbon (OC) and microbial biomass were observed along the gradient from natural to plantation forest. High annual variations were observed in soil N contents and in microbial biomass, while comparable spatial variations were observed within the natural forest. High ground-water levels resulted in increased accumulation of available Na⁺ and SO₄²⁻ in the natural forest soil, yet the concentrations of ions were at sub-saline levels. The increasing contents of available Mn, SO₄²⁻ or Cl⁻ had mostly positive effects on soil microbial activity across the sites, though the results indicate the existence of a certain ecological limit for soil microorganisms. Reintroduction of surface-water flooding should be considered in future forest and water management to promote the dilution of ions accumulated in soils and natural deposition of sediments rich in organic matter (OM) at the sites.

中文翻译：

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森林管理和水文学变化对中欧洪泛区森林土壤生化特性的影响

人为改变水情是威胁洪泛区森林稳定和生存的主要因素之一。这项研究提出了三种洪泛区林分不同人类改变水平的表土生物地球化学分析。从天然林到人工林，土壤有机碳（OC）和微生物生物量的含量均呈下降趋势。土壤氮含量和微生物生物量的年变化很大，而天然林中的空间变化却相当大。高地下水位导致可用的Na ⁺和SO ₄ ^2-积累增加在天然森林土壤中，离子的浓度仍在盐下水平。有效锰的含量增加，SO ₄ ^2-或Cl ^-对整个网站土壤微生物活动主要是积极的影响，但结果表明有一定的生态限制土壤中的微生物的存在。在未来的森林和水管理中，应考虑重新引入地表水驱替，以促进土壤中积累的离子的稀释和现场富含有机物（OM）的沉积物的自然沉积。