National Institute of Water and Atmospheric Research (NIWA), PO Box 11-115, Hillcrest, Hamilton 3216, New Zealand.
National Institute of Water and Atmospheric Research (NIWA), PO Box 11-115, Hillcrest, Hamilton 3216, New Zealand.
Mar Pollut Bull. 2022 Sep;182:114014. doi: 10.1016/j.marpolbul.2022.114014. Epub 2022 Aug 5.
Estuaries are ecologically valuable ecosystems that process nutrients through complex biogeochemical processes. Here we identify drivers and inhibitors of nitrogen removal in unvegetated intertidal sandflats at six sites in Manukau Harbour (37° 2.00'S 174° 42.00'E) to quantify the exchange of solutes across the sediment-water interface, with nitrogen removal rates (NRR) measured at two contrasting sites (PI and CB) near and far, respectively, from an historical wastewater treatment plant. Solute fluxes were paired with sediment and macrofauna community data to identify drivers of ecosystem function. Fluxes of oxygen, nitrogen and phosphorous were found to vary among sites, with differences attributed to variation in sediment characteristics (grain size, chlorophyll a, organic content) and macrofauna community structure. Mean NRR was found to vary between sites (PI = 32.2 vs CB = 217.9 μmol N/m/h), with bioturbating macrofauna (bivalves Austrovenus stutchburyi and Macomona liliana), microphytobenthic biomass, and exposure to nutrients likely key contributing drivers.
河口是具有生态价值的生态系统，通过复杂的生物地球化学过程来处理营养物质。在这里，我们确定了在马努考港（37°2.00'S 174°42.00'E）六个无植被潮间带沙滩地点中氮去除的驱动因素和抑制剂，以量化溶质在沉积物-水界面的交换，在距离历史废水处理厂远近不同的两个对比地点（PI 和 CB）测量氮去除率（NRR）。将溶质通量与沉积物和大型动物群落数据进行配对，以确定生态系统功能的驱动因素。发现氧气、氮和磷的通量在各地点之间存在差异，差异归因于沉积物特征（粒度、叶绿素 a、有机含量）和大型动物群落结构的变化。发现各地点的 NRR 平均值存在差异（PI = 32.2 与 CB = 217.9 μmol N/m/h），生物扰动大型动物（双壳类 Austrovenus stutchburyi 和 Macomona liliana）、微藻生物量以及暴露于营养物质可能是关键的驱动因素。
