Porewater sulfide, sediment sulfur, and organic matter data in West Falmouth Harbor, 2017-2019

West Falmouth Harbor (West Falmouth, MA, USA) has been experiencing a dramatic increase in nitrogen loading from an upgradient municipal wastewater treatment facility since the early 2000’s. As part of a long-term study into the effects of this nitrogen enrichment, each summer in 2017-2019 we sampled sediment and porewater to assess the relationship between belowground sulfur and carbon pools and seagrass health. This dataset contains information on porewater sulfide, porewater sulfate to chloride molar ratios, sediment organic matter, and sediment total sulfur from sites across three basins of West Falmouth Harbor that receive varying inputs of nitrogen. The data supports findings reported in Haviland et al., 2022 (https://doi.org/10.1002/lno.12025).