Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1029/2023WR034839
Licence creative commons licence
Title (Primary) Role of lakes, flood, and low flow events in modifying catchment-scale DOC:TN:TP stoichiometry and export
Author Fasching, C.; Boodoo, K.S.; Yao, H.; Rusak, J.A.; Xenopoulos, M.A.
Source Titel Water Resources Research
Year 2024
Department BOOEK
Volume 60
Issue 3
Page From e2023WR034839
Language englisch
Topic T5 Future Landscapes
Data and Software links https://doi.org/10.6084/m9.figshare.25043780
Supplements https://agupubs.onlinelibrary.wiley.com/action/downloadSupplement?doi=10.1029%2F2023WR034839&file=2023WR034839-sup-0001-Supporting+Information+SI-S01.pdf
Keywords dissolved organic carbon; nutrients; flood; stream; lake; stoichiometry
Abstract The balance of organic carbon (OC), nitrogen (N) and phosphorus (P) plays a crucial role in determining the processing, retention, and movement of these solutes across the aquatic continuum. Floods and droughts can significantly alter the quantity and ratios of OC:N:P export within inland waters, but how these ratios change, and are coupled within watersheds that integrate rivers and lakes, is not well known. We investigated the stoichiometry and export of dissolved organic carbon (DOC), total N (TN) and total P (TP) in two lake watersheds (10 inflows, 2 outflows) in the southern Boreal Shield over a 37-year period. Although DOC, TN, and TP concentration behaved similarly, DOC:TN:TP ratios varied seasonally, strongly modulated by stream discharge. DOC:TN, DOC:TP and TN:TP export initially increased rapidly with increasing discharge, peaking at 10%–20% exceedance of the annual discharge for DOC:TP and TN:TP ratios, indicating a rapid depletion of catchment OC sources. Both flood and low flow events resulted in lower DOC:TN and lower DOC:TP export—thereby increasing the relative contributions of stream TN and TP. Consequently, elevated annual discharge coupled with infrequent but high floods and periods of low flow events increased the contributions of TN and TP relative to DOC. Overall, the lakes retained DOC, while increasing TN relative to TP. Nonetheless, the flow regime played a role in modulating nutrient retention in the lakes, likely due to changes in residence time, and the interplay of physical, photochemical, and biological degradation processes.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=28921
Fasching, C., Boodoo, K.S., Yao, H., Rusak, J.A., Xenopoulos, M.A. (2024):
Role of lakes, flood, and low flow events in modifying catchment-scale DOC:TN:TP stoichiometry and export
Water Resour. Res. 60 (3), e2023WR034839 10.1029/2023WR034839