Effects of Methods & Time-to-Filtration on Soluble Reactive Phosphorus Concentration in Stream Water
Session: Poster session
Amanda Niederkorn, University of Waterloo, [email protected]
Laura Benakoun, Ministry of the Environment and Climate Change, [email protected]
Chris Parsons, University of Waterloo, [email protected]
Christopher Wellen, Ryerson University, [email protected]
Mohamed Mohamed, Ontario Ministry of the Environment and Climate Change, [email protected]
Abstract
Soluble reactive phosphorus (SRP) is operationally defined by time-to-filtration and filter pore size. Methodological variation across sampling projects, technical staff, and operating procedures may result in concentration data that are assumed to be comparable, though further validation of method equivalency may be warranted. Logistical challenges posed by relatively short times-to-filtration also impact studies using auto-samplers that collect and store refrigerated samples over multi-day events, and may produce unreliable SRP data. This study examined the effects of time-to-filtration from 0, 5, 24, 48, and 168 hour periods to reflect the range of sample holding times experienced by the use of auto-sampler systems in stream monitoring. This study also examined the effects of various filter media and methods (i.e., vacuum filtering vs. syringe filtering) on measured SRP concentrations. Water samples were collected and filtered at multiple time steps with varied filtering processes with 3 water sources used for comparison. Results indicate that time-to-filtration may be most sensitive within the first 5 hours but this appears inconsistent across stream water sources. Filtration via vacuum or syringe produced significantly different concentrations only when filtered immediately. Variation in filter type produces different concentrations in SRP primarily when there is a 24 hour delay or less.
1. Keyword
nutrients
2. Keyword
phosphorus
3. Keyword
water quality
4. Additional Keyword
filtration effects
5. Additional Keyword
automated water sampling
6. Additional Keyword
sampling methodology