N budgets and aquatic uptake in the Ipswich River basin, northeastern Massachusetts
Hopkinson, Charles S.
Rastetter, Edward B.
Vallino, Joseph J.
MetadataShow full item record
We calculated N budgets and conducted nutrient uptake experiments to evaluate the fate of N in the aquatic environment of the Ipswich River basin, northeastern Massachusetts. A mass balance indicates that the basin retains about 50% of gross N inputs, mostly in terrestrial components of the landscape, and the loss and retention of total nitrogen (TN) in the aquatic environment was about 9% of stream loading. Uptake lengths of PO4 and NH4 were measurable in headwater streams, but NO3 uptake was below detection (minimum detection limit = 0.05 μM). Retention or loss of NO3 was observed in a main stem reach bordered by wetland habitat. Nitrate removal in urban headwater tributaries was because of water withdrawals and denitrification during hypoxic events and in ponded wetlands with long water residence times. A mass balance using an entire river network indicates that basin-wide losses due to aquatic denitrification are considerably lower than estimates from several recent studies and range from 4 to 16% of TDN in stream loading. Withdrawals for domestic use restrict the runoff of headwater catchments from reaching the main stem during low base flow periods, thereby contributing to the spatial and temporal regulation of N export from headwater tributaries.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Water Resources Research 40 (2004): W11201, doi:10.1029/2004WR003172.
Suggested CitationWater Resources Research 40 (2004): W11201
Showing items related by title, author, creator and subject.
Calibration and application of B/Ca, Cd/Ca, and δ11B in Neogloboquadrina pachyderma (sinistral) to constrain CO2 uptake in the subpolar North Atlantic during the last deglaciation Yu, Jimin; Thornalley, David J. R.; Rae, James W. B.; McCave, I. Nick (John Wiley & Sons, 2013-05-30)The North Atlantic and Norwegian Sea are prominent sinks of atmospheric CO2 today, but their roles in the past remain poorly constrained. In this study, we attempt to use B/Ca and δ11B ratios in the planktonic foraminifera ...
Influence of biological carbon export on ocean carbon uptake over the annual cycle across the North Pacific Ocean Palevsky, Hilary I.; Quay, Paul D. (John Wiley & Sons, 2017-01-21)We evaluate the influences of biological carbon export, physical circulation, and temperature-driven solubility changes on air-sea CO2 flux across the North Pacific basin (35°N–50°N, 142°E–125°W) throughout the full annual ...
Uptake of heavy metals, organic trace contaminants and viruses by the Japanese oyster, Crassostrea gigas, grown in a waste recycling aquaculture system : final report Mann, Roger; Vaughn, James M.; Landry, Edward F.; Taylor, Rodman E. (Woods Hole Oceanographic Institution, 1979-05)A study of 24 weeks duration was carried out in which oysters (Crassostrea gigas) were grown in four regimes. These were: (i) on phytoplankton cultured in a mixture of secondary treated sewage effluent and seawater for ...