Fine particle retention within stream storage areas at base flow and in response to a storm event

J. D. Drummond*, L. G. Larsen, R. González-Pinzón, A. I. Packman, J. W. Harvey

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

39 Scopus citations

Abstract

Fine particles (1–100 µm), including particulate organic carbon (POC) and fine sediment, influence stream ecological functioning because they may contain or have a high affinity to sorb nitrogen and phosphorus. These particles are immobilized within stream storage areas, especially hyporheic sediments and benthic biofilms. However, fine particles are also known to remobilize under all flow conditions. This combination of downstream transport and transient retention, influenced by stream geomorphology, controls the distribution of residence times over which fine particles influence stream ecosystems. The main objective of this study was to quantify immobilization and remobilization rates of fine particles in a third-order sand-and-gravel bed stream (Difficult Run, Virginia, USA) within different geomorphic units of the stream (i.e., pool, lateral cavity, and thalweg). During our field injection experiment, a thunderstorm-driven spate allowed us to observe fine particle dynamics during both base flow and in response to increased flow. Solute and fine particles were measured within stream surface waters, pore waters, sediment cores, and biofilms on cobbles. Measurements were taken at four different subsurface locations with varying geomorphology and at multiple depths. Approximately 68% of injected fine particles were retained during base flow until the onset of the spate. Retention was evident even after the spate, with 15.4% of the fine particles deposited during base flow still retained within benthic biofilms on cobbles and 14.9% within hyporheic sediment after the spate. Thus, through the combination of short-term remobilization and long-term retention, fine particles can serve as sources of carbon and nutrients to downstream ecosystems over a range of time scales.

Original languageEnglish (US)
Pages (from-to)5690-5705
Number of pages16
JournalWater Resources Research
Volume53
Issue number7
DOIs
StatePublished - Jul 2017
Externally publishedYes

Keywords

  • benthic biofilms
  • fine particles
  • hyporheic storage
  • immobilization
  • remobilization
  • storm event

ASJC Scopus subject areas

  • Water Science and Technology

Fingerprint

Dive into the research topics of 'Fine particle retention within stream storage areas at base flow and in response to a storm event'. Together they form a unique fingerprint.

Cite this