Freshwater and saline loads of dissolved inorganic nitrogen to Hood Canal and Lynch Cove, western Washington

Paulson, Anthony J.; Konrad, Christopher P.; Frans, Lonna M.; Noble, Marlene A.; Kendall, Carol; Josberger, Edward G.; Huffman, Raegan L.; Olsen, Theresa D.

doi:10.3133/sir20065106

Cited by 14 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Once transported to the sediment, remineralized Cd is sequestered under reducing conditions as a sulfide mineral. This process has been documented in sediments of a Vancouver Island inlet (Pedersen et al 1989) and of the Laurentian Trough in the St. Lawrence Estuary (Gobeil et al 1987). These findings support the use of Cd as a tracer for reducing conditions in deep waters or at the sediment-water interface, which result from high productivity and/or low ventilation.…”

Section: Discussionmentioning

confidence: 67%

“…Coastal upwelling provides an additional source of nutrients and fuels a high rate of primary productivity (*400 g carbon/m 2 /year (Antoine et al 1996)) indicating the coupling between ocean and estuary may be a more significant nutrient source than just watershed-derived nutrients and OM. Paulson et al (2006) estimated the oceanic load of dissolved inorganic nitrogen (DIN) to Hood Canal was *94% of the nitrogen (N) budget. Therefore, Puget Sound has generally been lightlimited (Collias and Lincoln 1977) and only periodically nutrient-limited during summer blooms (Mackas and Harrison 1997) and in nearshore regions (Thom et al 1994).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Natural and Post-Urbanization Signatures of Hypoxia in Two Basins of Puget Sound: Historical Reconstruction of Redox Sensitive Metals and Organic Matter Inputs

2011

View full text Add to dashboard Cite

Hypoxia has been observed in Hood Canal, Puget Sound, WA, USA since the 1970s. Four long sediment cores were collected in 2005 and age-dated to resolve natural and post-urbanization signatures of hypoxia and organic matter (OM) sources in two contrasting basins of Puget Sound: Main Basin and Hood Canal. Paleoecological indicators used for sediment reconstructions included pollen, stable carbon and nitrogen isotopes (d 13 C and d 15 N), biomarkers of terrestrial OM (TOM), biogenic silica (BSi), and redoxsensitive metals (RSM). The sedimentary reconstructions illustrated a gradient in RSM enrichment factors as Hood Canal [ Main Basin, southern [ northern cores, and pre1900s [ 1900-2005. The urbanization of Puget Sound watersheds during the 1900s was reflected as shifts in all the paleoecological signatures. Pollen distributions shifted from predominantly old growth conifer to successional alder, dominant OM signatures recorded a decrease in the proportion of marine OM (MOM) concomitant with an increase in the proportion of TOM, and the weight % of BSi decreased. However, these shifts were not coincidental with an overall increase in the enrichment of RSM or d 15 N signatures indicative of cultural eutrophication. The increased percentage of TOM was independently verified by both the elemental ratios and lignin yields. In addition, isotopic signatures, BSi, and RSMs all suggest that OM shifts may be due to a reduction in primary productivity rather than an increase in OM regeneration in the water column or at the sediment/water interface. Therefore, the reconstructions suggested the Hood Canal has been under a more Electronic supplementary material The online version of this article (oxygenated ''stance'' during the twentieth century compared to prior periods. However, these 2005 cores and their resolutions do not encompass the period of high resolution water column measurements that showed short-lived hypoxia events and fish kills in Hood Canal during the early twenty-first century. The decoupling between the increased watershedscale anthropogenic alterations recorded in the OM signatures and the relatively depleted RSM during the twentieth century suggests that physical processes, such as deep-water ventilation, may be responsible for the historical variation in oxygen levels. Specifically, climate oscillations may influence the ventilation and/or productivity of deep water in Puget Sound and particularly their least mixed regions.

show abstract

Section: Discussionmentioning

confidence: 67%

Section: Introductionmentioning

confidence: 99%

Natural and Post-Urbanization Signatures of Hypoxia in Two Basins of Puget Sound: Historical Reconstruction of Redox Sensitive Metals and Organic Matter Inputs

2011

View full text Add to dashboard Cite

show abstract

“…The dynamics of hypoxia in diverse regions, including the Chesapeake Bay, Gulf of Mexico, Hood Canal, and Long Island Sound, has been shown to be linked to physical and biological forcing, such as riverine nutrient input varying between wet and dry years [ Bianchi et al ., ; Hagy et al ., ; Paulson et al ., ], mixing and lateral advection due to winds [ Sanford et al ., ; Scully , ], stratification or overturning of the water column [ Bianchi et al ., ; Lee and Lwiza , ; Warner et al ., ], and reduced DO solubility with increasing water temperature [ Najjar et al ., ; Scully , ], all of which may be influenced by climate change. Using the yearly maximum hypoxic volume, the yearly cumulative hypoxic volume, and the yearly duration of hypoxia to characterize the severity of low DO has the additional benefit of incorporating changes in hypoxia caused by climate change.…”

Section: Discussionmentioning

confidence: 99%

Combining observations and numerical model results to improve estimates of hypoxic volume within the Chesapeake Bay, USA

Bever

Friedrichs

et al. 2013

J. Geophys. Res. Oceans

View full text Add to dashboard Cite

[1] The overall size of the ''dead zone'' within the main stem of the Chesapeake Bay and its tidal tributaries is quantified by the hypoxic volume (HV), the volume of water with dissolved oxygen (DO) less than 2 mg/L. To improve estimates of HV, DO was subsampled from the output of 3-D model hindcasts at times/locations matching the set of [2004][2005] stations monitored by the Chesapeake Bay Program. The resulting station profiles were interpolated to produce bay-wide estimates of HV in a manner consistent with nonsynoptic, cruise-based estimates. Interpolations of the same stations sampled synoptically, as well as multiple other combinations of station profiles, were examined in order to quantify uncertainties associated with interpolating HV from observed profiles. The potential uncertainty in summer HV estimates resulting from profiles being collected over 2 weeks rather than synoptically averaged $5 km 3 . This is larger than that due to sampling at discrete stations and interpolating/extrapolating to the entire Chesapeake Bay (2.4 km 3 ). As a result, sampling fewer, selected stations over a shorter time period is likely to reduce uncertainties associated with interpolating HV from observed profiles. A function was derived that when applied to a subset of 13 stations, significantly improved estimates of HV. Finally, multiple metrics for quantifying bay-wide hypoxia were examined, and cumulative hypoxic volume was determined to be particularly useful, as a result of its insensitivity to temporal errors and climate change. A final product of this analysis is a nearly three-decade time series of improved estimates of HV for Chesapeake Bay.

show abstract

“…In the spring and summer, many Salish Sea subbasins regularly experience algae blooms, and rapid consumption of nutrients from the euphotic zone resulting in near eutrophic conditions (e.g., Bernhard & Peele, ; Harrison et al, ; Newton et al, , ; Newton & van Voorhis, ; Thom et al, ; Thom & Albright, ). Evidence of low dissolved oxygen (DO) levels and hypoxia (DO concentrations <2 mg/L) has been documented in several basins (e.g., Albertson et al, , ; Barnes & Collias, ; Embrey & Inkpen, ; Harrison et al, ; Mohamedali et al, ; Newton et al, ; Paulson et al, ; Puget Sound Action Team, ; Roberts et al, ; Stockner et al, ). Khangaonkar et al () showed that eliminating all land‐based nutrient sources would result in notable water‐quality improvement, including a reduction in algal biomass (≈5.4%), reduction in sediment oxygen demand (≈17.1%), significant reduction in hypoxic area (≈39%), and reduction in exposure in area days to bottom‐layer hypoxia (≈62%) within the Salish Sea.…”

Section: Introductionmentioning

confidence: 99%

Salish Sea Response to Global Climate Change, Sea Level Rise, and Future Nutrient Loads

Khangaonkar

Nugraha

et al. 2019

JGR Oceans

View full text Add to dashboard Cite

Given annual occurrences of hypoxia, harmful algal blooms, and evidence of coastal acidification, the potential impacts of climate change on water quality are of increasing concern in the U.S. Pacific Northwest estuaries such as the Salish Sea. While large‐scale global climate projections are well documented, our understanding of the nearshore estuarine‐scale response is not as well developed. In this study, the future response within the Salish Sea fjord‐like environment was examined using the Salish Sea Model driven by downscaled outputs from the National Center for Atmospheric Research climate model Community Earth System Model. We simulated a single projection of 95‐year change under the representative concentration pathway 8.5 greenhouse gas emissions scenario. Results indicate that higher temperatures, lower pH, and decreased dissolved oxygen levels in the upwelled shelf waters in the future would propagate into the Salish Sea. Results point to potential changes in average Salish Sea temperature (≈+1.51 °C), dissolved oxygen (≈−0.77 mg/L), and pH (acidification −0.18 units) in the Y2095 relative to historical Y2000. The algal biomass in the Salish Sea could increase by ≈23% with a potential species shift from diatoms toward dinoflagellates. The region of annually recurring hypoxia could increase from <1% today to ≈16% in the future. The results suggest that the future response in the Salish Sea is less severe relative to the change predicted near the continental shelf boundary. This resilience of the Salish Sea may be attributed to the existence of strong vertical circulation cells that provide mitigation and serve as a physical buffer, thus keeping waters cooler, more oxygenated, and less acidic.

show abstract

Freshwater and saline loads of dissolved inorganic nitrogen to Hood Canal and Lynch Cove, western Washington

Cited by 14 publications

References 10 publications

Natural and Post-Urbanization Signatures of Hypoxia in Two Basins of Puget Sound: Historical Reconstruction of Redox Sensitive Metals and Organic Matter Inputs

Natural and Post-Urbanization Signatures of Hypoxia in Two Basins of Puget Sound: Historical Reconstruction of Redox Sensitive Metals and Organic Matter Inputs

Combining observations and numerical model results to improve estimates of hypoxic volume within the Chesapeake Bay, USA

Salish Sea Response to Global Climate Change, Sea Level Rise, and Future Nutrient Loads

Contact Info

Product

Resources

About