Summer 2017 porewater and sediment geochemistry data at Second Creek, a sulfate-impacted riparian wetland in northeast Minnesota

Water and sediment chemistry data were collected over the summer and
fall of 2017 at Second Creek, a riparian wetland study site near
Aurora, MN, to understand sulfur and methane processes. Porewaters
were collected with two distinct methods “peepers” (multi-chambered
equilibrium dialysis samplers) that allow for high vertical
resolution but 2-3 week averaged temporal resolution, and rhizon
samplers that enable instantaneous temporal resolution but have
lower spatial resolution. Porewaters were analyzed for dissolved
cations, anions, sulfide, methane, iron(II)/iron(III), and pH.
Sediment cores were analyzed for acid volatile sulfide, and sulfur
and iron speciation via X-ray absorption spectroscopy.

2017年夏秋季，研究团队于美国明尼苏达州奥罗拉附近的河岸湿地研究站点Second Creek（第二溪）采集水与沉积物化学数据，旨在解析硫循环与甲烷代谢相关的生物地球化学过程。本次研究采用两种差异化方法采集孔隙水：其一为peepers（多室平衡透析采样器），该手段可实现较高的垂直分辨率，但时间分辨率为2~3周的平均结果；其二为rhizon采样器，其可实现瞬时时间分辨率，但空间分辨率相对较低。随后对孔隙水开展溶解态阳离子、阴离子、硫化物、甲烷、二价铁/三价铁以及pH值的检测分析。此外，通过X射线吸收光谱法（X-ray absorption spectroscopy）对沉积物岩芯的酸挥发性硫化物、硫及铁的化学形态进行了测定分析。