Utah Lake Subwatersheds Solute Chemistry

This dataset includes stream solute concentrations measured in the Utah Lake Watershed. Because synoptic sampling requires rapid data collection in a short period of time, we used a citizen science approach to collect over 200 water samples in a single day. Samples were collected over three citizen science synoptic water sampling events which were conducted in March (Spring), July (Summer), and October (Fall) 2018. Volunteers were trained in person on the day of sampling and were provided with site coordinates, detailed written instructions, and sampling materials. Upon completion of sampling, participants returned their sampling kits, samples were manually inspected for quality control and any samples with incomplete data or other irregularities were discarded. Samples were filtered in the field with DI water-rinsed 0.45 µm cellulose acetate filters (Millipore Millex-GV) and immediately frozen or refrigerated and analyzed within 2 weeks of sampling. Anions (NO^3-, NO^2-, SO[4] ^2-, Cl-, and PO[4] ^3-) and cations (NH^4+) were quantified by ion chromatography (Dionex Thermofisher HPIC). Soluble reactive phosphorus was quantified colorimetrically using the ascorbic acid method (ref). We assumed phosphorus concentrations to be equal to the average of both the values determined by ion chromatography and ascorbic acid methods. Dissolved organic carbon (DOC) and total dissolved nitrogen (TN) were quantified using a C/N auto-analyzer (Elementar, Ronkonkoma, NY). Dissolved inorganic nitrogen (DIN) was calculated as the sum of N species (i.e. NO^3-, NO^2-, and NH^4+) from the ion chromatography analysis. We used the application USGS StreamStats to delineate watersheds and calculate watershed area (km2). The application also calculates percent land cover from the National Land Cover Database (NLCD) 1992 and 2011, classified as forested, developed, impervious surface, or herbaceous upland for each site.