Presentation Abstract
Fluctuations in Puget Sound water quality reflect a combination of natural variability and anthropogenic influence. Predictions of how future changes will unfold requires an understanding of the complex interplay between these factors. Recent and ongoing measurement of water quality parameters allow a thorough assessment of variability over short time scales, but understanding changes over longer (e.g., decadal) timescales is critical for forecasting future changes. Examining long term trends requires the use of historical data, however, measurements that pre-date modern monitoring programs can be scarce, and the detection limits are often higher than newer analytical techniques. Here, we will consider several possible methods to stitch together modern and historical data records of dissolved oxygen and nutrient concentrations while accounting for differences in sample rate, temporal coverage, and sensitivity of analytical techniques. To test different data analysis methods, data records with good temporal coverage that show discernible trends and/or high covariance with other environmental parameters will be used as the basis for simulating data with spotty temporal coverage (as might be expected for less commonly measured biogeochemical parameters like deep dissolved oxygen). Selected trend analyses will then be applied to these simulated time series records to assess method effectiveness in identifying a known feature. Top performing methods for trend analysis will then be applied to key biogeochemical parameters such as nitrate and deep dissolved oxygen. We report on the major covariates and trends identified and the associated statistical confidence intervals. These results will be part of a larger effort to determine how existing trends might play out under different anthropogenic input scenarios.
Session Title
Posters: Species & Food Webs
Keywords
Nutrient, Water Quality, Historical, Oxygen, Puget Sound, Marine
Conference Track
SSE18: Posters
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE18-114
Start Date
5-4-2018 11:30 AM
End Date
5-4-2018 1:30 PM
Type of Presentation
Poster
Genre/Form
conference proceedings; presentations (communicative events); posters
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Water quality--Washington (State)--Puget Sound--Measurement; Climatic changes--Effect of human beings on--Washington (State)--Puget Sound
Geographic Coverage
Puget Sound (Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Included in
Fresh Water Studies Commons, Marine Biology Commons, Natural Resources and Conservation Commons, Terrestrial and Aquatic Ecology Commons
Extending observations further: using historic biogeochemical data to understand trends in Puget Sound
Fluctuations in Puget Sound water quality reflect a combination of natural variability and anthropogenic influence. Predictions of how future changes will unfold requires an understanding of the complex interplay between these factors. Recent and ongoing measurement of water quality parameters allow a thorough assessment of variability over short time scales, but understanding changes over longer (e.g., decadal) timescales is critical for forecasting future changes. Examining long term trends requires the use of historical data, however, measurements that pre-date modern monitoring programs can be scarce, and the detection limits are often higher than newer analytical techniques. Here, we will consider several possible methods to stitch together modern and historical data records of dissolved oxygen and nutrient concentrations while accounting for differences in sample rate, temporal coverage, and sensitivity of analytical techniques. To test different data analysis methods, data records with good temporal coverage that show discernible trends and/or high covariance with other environmental parameters will be used as the basis for simulating data with spotty temporal coverage (as might be expected for less commonly measured biogeochemical parameters like deep dissolved oxygen). Selected trend analyses will then be applied to these simulated time series records to assess method effectiveness in identifying a known feature. Top performing methods for trend analysis will then be applied to key biogeochemical parameters such as nitrate and deep dissolved oxygen. We report on the major covariates and trends identified and the associated statistical confidence intervals. These results will be part of a larger effort to determine how existing trends might play out under different anthropogenic input scenarios.
