In flooded soils and sediments, bioturbating invertebrates rework sediment and convey oxygenated surface water through burrowing, creating a mosaic of adjacent anoxic and oxic patches while simultaneously translocating and transforming nutrients as they feed and excrete. We investigated the impacts of two functionally contrasting bioturbators (gallery-network burrower Lumbriculus variegatus and U-shaped burrower Ephemera simulans) on oxygen availability and nutrient fluxes in wetland sediments. To assess excretion contributions, we also incubated bioturbators in sand-water microcosms. Fine-scale oxygen measurements combined with flux rates of redox-sensitive and conservative ions reveal that both bioturbators introduced oxygen to sediments. U-shaped burrowers facilitated measurable oxygen introduction into sediments while gallery-network burrowers did not. However, gallery-network burrowers showed evidence of oxidizing reduced solutes in sediments, which suggests that oxygen is being introduced. At high densities, both bioturbators promoted sufficient iron oxidation to sequester phosphorus from surface water into sediments, effectively counteracting phosphorus release from excretion. Conversely, bioturbation caused nitrate release into surface water, likely driven by excretion of ammonia followed by nitrification. Gallery-network burrowers facilitated P retention in sediments but contributed N to surface water, while U-shaped burrowers showed similar, but less pronounced trends. Bioturbators have profound, but variable, effects on sediment-surface water nutrient exchange in wetlands. Sediment characteristics, bioturbator density, and bioturbation mode regulate both the amount of oxygen introduced to normally anoxic sediments and its reactions with sediment substrates, shaping the magnitude and direction of bioturbator-induced nutrient fluxes.

在淹没的土壤和沉积物中，生物扰动的无脊椎动物会改造沉积物，并通过挖洞输送含氧的地表水，形成相邻缺氧和含氧斑块的镶嵌物，同时在进食和排泄时转移和转化养分。我们研究了两种功能不同的生物扰动物（画廊网络穴居动物Lumbriculus variegatus和 U 形穴居动物蜉蝣 simulans）对湿地沉积物中氧气利用率和养分通量的影响。为了评估排泄贡献，我们还在沙水微观世界中培养生物扰动器。精细的氧气测量与氧化还原敏感和保守离子的通量率相结合表明，两种生物扰动器都向沉积物中引入了氧气。U 形挖洞器有利于将可测量的氧气引入沉积物中，而廊道网络挖洞器则不然。然而，廊道网络挖掘者显示出氧化沉积物中还原溶质的证据，这表明氧气正在被引入。在高密度下，两个生物扰动器都促进了充分的铁氧化，将地表水中的磷隔离到沉积物中，有效地抵消了排泄中的磷释放。相反，生物扰动导致硝酸盐释放到地表水中，这可能是由氨排泄和硝化作用驱动的。廊道网络穴居动物促进了沉积物中磷的保留，但向地表水贡献了氮，而 U 形穴居动物则表现出类似但不太明显的趋势。生物扰动器对湿地沉积物-地表水养分交换具有深远但可变的影响。沉积物特征、生物扰动密度和生物扰动模式调节引入正常缺氧沉积物的氧气量及其与沉积物底物的反应，从而形成生物扰动引起的营养物通量的大小和方向。