Physiochemical Investigations of the Surface Water of Little Spokane River
Faculty Sponsor
William Ntow, Whitworth University
Research Project Abstract
The physiochemical characteristics of the surface water in the Little Spokane River at the Verbrugge Environmental Center (VEC) near Newport, Washington were assessed in two different seasons. Because the VEC is located near the source of the Little Spokane River, surface water quality data at this site can show the background concentrations for nutrients like nitrogen and phosphorus before significant contamination is likely to occur. UV-vis spectrophotometry was used to obtain absorbance data that were used to determine the concentrations of selected nutrients. Soluble phosphorus concentrations were measured using the molybdenum blue-ascorbic acid method and showed low and often undetectable values (<0.15mg P/L). Soluble nitrogen concentrations were measured using the cadmium reduction method and were found to be in a range from 0.4 mg N/L to the detection limit of <0.05 mg N/L. Total nitrogen and phosphorus values were obtained from persulfate digested samples. Total nitrogen was found in a range of 1.0 mg N/L to 0.1 mg N/L. Total phosphorous was found to be below the detection limit in the winter but had an average value of 7.7 mg P/L in the summer. The data indicated normal conditions for an oligotrophic ecosystem according to the Washington State Department of Ecology standards for total nitrogen.
Session Number
PS2
Location
Graves Gym
Abstract Number
PS2-b
Physiochemical Investigations of the Surface Water of Little Spokane River
Graves Gym
The physiochemical characteristics of the surface water in the Little Spokane River at the Verbrugge Environmental Center (VEC) near Newport, Washington were assessed in two different seasons. Because the VEC is located near the source of the Little Spokane River, surface water quality data at this site can show the background concentrations for nutrients like nitrogen and phosphorus before significant contamination is likely to occur. UV-vis spectrophotometry was used to obtain absorbance data that were used to determine the concentrations of selected nutrients. Soluble phosphorus concentrations were measured using the molybdenum blue-ascorbic acid method and showed low and often undetectable values (<0.15mg P/L). Soluble nitrogen concentrations were measured using the cadmium reduction method and were found to be in a range from 0.4 mg N/L to the detection limit of <0.05 mg N/L. Total nitrogen and phosphorus values were obtained from persulfate digested samples. Total nitrogen was found in a range of 1.0 mg N/L to 0.1 mg N/L. Total phosphorous was found to be below the detection limit in the winter but had an average value of 7.7 mg P/L in the summer. The data indicated normal conditions for an oligotrophic ecosystem according to the Washington State Department of Ecology standards for total nitrogen.
