Trask River Watershed Study: Stream chemistry, 2006-2016

These data are a portion of the larger Trask River Watershed Study which was conducted in the East Fork of the South Fork Trask River of the Coast Range of western Oregon. Water samples were collected from headwater study streams as well as downstream segments and analyzed for dissolved carbon, nutrients (primarily nitrogen and phosphorus) as well as selected anions and cations. Synoptic surveys were conducted before and after harvest and provide insights into the effects of harvest treatments both locally and downstream. The Trask River Watershed study area consists of 4 large catchments: Pothole Creek, Gus Creek, Rock Creek, and Upper Main Trask. Within each of the four catchments, 2-4 headwater sites and a downstream site were sampled. In general, Trask River Watershed study data were collected during pre-harvest (2006-2011) and post-harvest (2013-2016) periods, from treated and reference headwater watersheds and from downstream sites. Sampling for the data included in this data publication began in August 2006 and late June samples were collected annually at all sites beginning in 2008 and continuing through 2016. No sampling occurred in 2012 during harvest. Downstream sites were also sampled during late summer (end of August or early September) in 2009, 2010, 2013, and 2014.
These data are a portion of the larger Trask River Watershed Study. The general objectives of the Trask River Watershed Study were to investigate the effects of forest harvest on the physical, chemical and biological characteristics of small headwater streams, and the extent to which alterations in stream conditions caused by harvest along headwater channels influence the physical, chemical and biological characteristics of downstream fish-bearing streams. The primary role of this sampling was to characterize any inherent differences in dissolved chemical concentrations after harvest.