AbstractsGeography &GIS

Contribution of organic matter to suspended sediment and turbidity in streams with differing forest cover

by Jeffrey T Hayes

Institution: Humboldt State University
Year: 2015
Keywords: Suspended sediment; Organic matter; Turbidity; Forest cover
Posted: 02/05/2017
Record ID: 2085041
Full text PDF: http://hdl.handle.net/10211.3/143276


In this study, I quantified particulate organic matter and total suspended sediment (TSS) discharged during four storms from six tributaries of the Mattole River in northern California during the 2012 hydrological year. The six catchments ranged in size from 1.42 to 5.41 km2. The percentage of forest cover ranged from 30 to 97%. Sampling was conducted to evaluate hypotheses that more organic matter is discharged from catchments with more forested area, the percentage of organic matter discharged is greater with more forest cover, and the percentage of organic matter is negatively related with turbidity. Coarse particulate organic matter in the streams comprised less than 1% of the organic matter discharged. Fine particulate organic matter (FPOM) in suspension did not differ significantly between more forested and less forested catchments (p=1, n1=3, n2=3, W=10). The percentage of organic matter discharged is not greater with more forest cover because R2 values of the relationship between the percentage of organic matter and TSS ranged from 0.082 to 0.371. Also, I cannot conclude that FPOM is negatively related with turbidity because the R2 values ranged from 0.081 to 0.262. Low sample sizes and high variability in organic matter contributed to the rejection of my hypotheses. Advisors/Committee Members: Brenneman, Kristine.