Dissolved inorganic nutrient concentration of Lena River water from 20.04.2018 (#1) to 11.09.2019 (#201)

We collected water samples from the river surface in the center of the Olenekskaya Channel near Samoylov Island using a pre-rinsed HDPE 1 L bottle. During the open water period (June to October), water was sampled from a small boat, and during ice-covered period (November to May), through a hole drilled through the river ice. Some samples during the river ice break-up (between May and June) as well as some samples during the ice freeze-up in October were taken from the shore due to the inaccessibility of a more centered location on the river channel. Samples for dissolved inorganic nutrient analysis (silicate, ammonium, phosphate, nitrite, and nitrate) were filtered through a 0.45 μm cellulose acetate filter, which had been rinsed with 20 mL sample water. Dissolved inorganic nutrients for samples #001 - #201 (20 Apr. 2018 to 11 Sept. 2019) were measured at the Otto Schmidt Laborator in St. Petersburg, Russia. Nutrient concentrations were analyzed on an automated continuous flow system (San+, SKALAR, Netherlands) with standard colorimetric techniques (Aminot et al. 2009).