Contemporary changes in dissolved organic carbon (DOC) in human-dominated rivers: is there a role for DOC management?
Article first published online: 11 AUG 2011
© 2011 Blackwell Publishing Ltd
Special Issue: Achieving Ecological Outcomes: Aquatic Ecological Responses to Catchment Management
Volume 57, Issue Supplement s1, pages 26–42, July 2012
How to Cite
STANLEY, E. H., POWERS, S. M., LOTTIG, N. R., BUFFAM, I. and CRAWFORD, J. T. (2012), Contemporary changes in dissolved organic carbon (DOC) in human-dominated rivers: is there a role for DOC management?. Freshwater Biology, 57: 26–42. doi: 10.1111/j.1365-2427.2011.02613.x
- Issue published online: 21 JUN 2012
- Article first published online: 11 AUG 2011
- (Manuscript accepted 12 April 2011)
- dissolved organic carbon;
- land-use change;
1. Dissolved organic carbon (DOC) plays a central role in the dynamics of stream and river ecosystems, affecting processes such as metabolism, the balance between autotrophy and heterotrophy, acidity, nutrient uptake and bioavailability of toxic compounds. However, despite its importance to stream processes, restoration and management activities rarely incorporate DOC as a major management criterion.
2. Lotic DOC pools reflect terrestrial organic carbon accumulation, transfer to the river channel and aquatic processing. In pristine landscapes, characteristics such as topography, climate, and landscape composition are strong predictors of terrestrial accumulation and transfer. Within aquatic systems, the quantity and form of DOC are altered by a variety of processes including primary production, microbial breakdown, sorption to particles and photodegradation.
3. Terrestrial accumulation, transfer and aquatic processing of DOC in agricultural and other human-dominated landscapes are all subject to substantial change. Consequently, DOC pools in agricultural streams likely differ from historic conditions and now include more labile material and low concentrations of a variety of ubiquitous synthetic organic compounds (e.g. pesticides, antibiotics).
4. Although DOC change in agricultural streams and associated ecological consequences are expected to be widespread, current understanding and relevant data needed to manage affected systems are surprisingly scarce.
5. Wetland and riparian restoration projects have variable effects on fluvial DOC regimes, but management at this intermediate scale is a realistic compromise between the small extent of most restoration projects and the large spatial scale over which organic carbon impairment occurs.