Enhancement of chlorophyll a production in Gulf Stream surface seawater by synthetic versus natural rain

Willey, Joan D.; Paerl, Hans W.

doi:10.1007/bf00350023

Cited by 24 publications

(16 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, in this study, rainfall associated with Hurricane Gordon was relatively low (Ͻ4 cm in 3 d, Table 2). Hurricanes are commonly capable of delivering Ն10 cm of rain during their passage through a region (Zeeman 1985;Paerl and Fogel 1994), but these oce- anic rains typically have relatively low concentrations of DIN compared to continental rains (Willey and Kiefer 1993). In the rain collected onboard ship during this study, concentrations of dissolved N were significant, but owing to low rainfall amounts over the continental shelf region, direct N input from atmospheric deposition was not substantial.…”

Section: Discussionmentioning

confidence: 75%

See 1 more Smart Citation

Biological and isotopic changes in coastal waters induced by Hurricane Gordon

Fogel

Aguilar

Cuhel

et al. 1999

Limnology & Oceanography

View full text Add to dashboard Cite

The effects of a major storm event (Hurricane Gordon) on the biogeochemistry of Atlantic coastal and Gulf Stream waters were investigated during a research cruise in November 1994. Prestorm, NH , NO , and PO ϩ Ϫ Ϫ 3 4 3 4concentrations were consistently well below 1 M, whereas after the storm, nutrient concentrations were higher in the surface-water samples: Ͼ2 M, in some instances. Primary and secondary (bacterial) production were stimulated by factors of 5 and 2, respectively, up to 4 d following the storm. Bioassay experiments showed that additions of inorganic N stimulated chlorophyll a (Chl a) concentrations, 14 CO 2 fixation, and stable isotope fractionations both before and after the storm, but the addition of phosphate had a greater impact in post-storm experiments. The ␦ 15 N of particulate nitrogen (PN) varied from ϩ5 to ϩ1.5‰ before Gordon, then afterward attained a consistent value of ϩ3.0‰. Sedimentary organic ␦ 15 N values were similar to water-column organic N, and the ␦ 15 N of dissolved NH from surface sediments (ϩ4.0‰) almost matched the ␦ 15 N of water-column particulates. These results indicate ϩ 4 that storm-generated winds mixed sediments along with dissolved nutrients into surface waters, which supported a rapid increase in water-column primary production.Interactions between atmospheric processes and primary production in the world's oceans are striking during and after major storm events over continental shelf regions. N, a lim- AcknowledgmentsWe thank Malia Go for technical assistance with the nutrient analysis. Special thanks to the crew of the RV Cape Hatteras for their competent assistance before, during, and after the storm. This work was funded by an NSF grant (Ecosystems and Biological Oceanography; [DEB 9210495]) to M.L.F. and H.W.P. We thank George Cody, Mark Teece, and Jennifer Blank for helpful reviews.

show abstract

Section: Discussionmentioning

confidence: 75%

“…trations fall within the range of rain events observed along the North Carolina coast (Willey and Kiefer 1993;Paerl and Fogel 1994). Dissolved inorganic nitrogen (DIN) input via rainfall during Hurricane Gordon was 760 mol m Ϫ2 over the 2-d storm time (Table 2).…”

Section: Resultsmentioning

confidence: 91%

Biological and isotopic changes in coastal waters induced by Hurricane Gordon

Fogel

Aguilar

Cuhel

et al. 1999

Limnology & Oceanography

View full text Add to dashboard Cite

show abstract

“…This hydrogen peroxide effect occurred whether the chl a response was to FeC13 alone, EDTA alone, or Fe(1II)EDTA. This lack of response was not due to salinity dilution because chl a increases have been observed following addition of synthetic rainwater without hydrogen peroxide in similar bioassay experiments (Paerl 1985, Willey & Cahoon 1991, Willey & Paerl 1993, Paerl et aI. 1994.…”

Section: Resultsmentioning

confidence: 73%

“…Three bioassays were conducted in June and November of 1993, and May of 1994, with continental shelf surface seawater (salinities 35.2, 35.9 and 35.6%0 respectively) approximately 100 km northwest of the Gulf Stream station. Bioassays were conducted using methods described extensively in Paerl et al (1990), Willey & Cahoon (1991), Willey & Paerl (1993 and Paerl et al (1994). Briefly, bioassay seawater was incubated at sea surface temperature (k2"C) in 4 l polyethylene Cubitainers for 2 to 3 d wlth light intensity controlled to approximately 50% of incident by neutral density screening.…”

Section: Methodsmentioning

confidence: 99%

“…Rainwater concentrations of the phytoplankton nutrients nitrate and ammonium vary substantially in this region (Willey & l e f e r 1993), as do concentrations of the photochemical oxidant hydrogen peroxide (Willey et al 1996). Hence, rain from different storms may have different impacts upon surface waters (Willey & Cahoon 1991, Willey & Paerl 1993.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Impact of rainwater hydrogen peroxide on chlorophyll a content of surface Gulf Stream seawater off North Carolina, USA

Willey¹,

Paerl²,

Go³

1999

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Bioassays indicate addition of hydrogen peroxide in concentrations similar to rain sometimes decreases chlorophyll a (chl a) production in surface Gulf Stream seawater. Bioassays were conducted on shipboard in the spring and autumn of 1993, 1994, and 1995. using surface Gulf Stream seawater collected off the coast of North Carolina. Chl a increases were observed after addition of FeC13 (in 1 of 5 bioassays), iron (111) EDTA (6 of 6 bioassays), or EDTA alone (4 of 4 bioassays). The chl a increases were suppressed significantly in 7 of 11 of these bioassays when the bioassay seawater was initially diluted by 1 % with a 30 or 40 p M solution of hydrogen peroxide (a concentration similar to rainwater). Hydrogen peroxide induced inhibition of chl a production was not observed in bioassays in w h~c h chl a increased in response to addltion of nitrate or ammonium, hence the growth inhibition was associated with added metal or complexing agent. Rainwater therefore plays a complex role in primary productivity in surface seawater, with the specific effect dependent upon rainwater concentrations of nitrate, ammonium, trace metals and hydrogen peroxide, as well as on the extent of nitrogen limitation and the oxidant concentration in the surface seawater.

show abstract

Influence of precipitation events on phytoplankton biomass in coastal waters of the eastern United States

Kim

Najjar

Lee

2014

Global Biogeochemical Cycles

View full text Add to dashboard Cite

Precipitation over the ocean surface in the vicinity of industrialized and populated coastlines can increase the ocean nitrate concentration and consequently enhance ocean primary productivity. Using satellite data and a meteorological reanalysis product, we evaluated the impact of precipitation events on the chlorophyll a concentration in coastal and offshore waters located downwind of the eastern United States. We found that in low-nutrient areas (defined as having nitrate concentrations < 1 μM) precipitation events were associated with increased levels of chlorophyll a (up to approximately 15%), but in high-nutrient areas (nitrate concentrations > 1 μM) they were associated with decreased levels. These contrasting responses of chlorophyll a concentration to precipitation were attributed to the correlation of precipitation with wind speed and to other factors (nutrients and light) limiting phytoplankton growth. Increases in wind speed accompanied by precipitation events typically deepen the mixed layer, which can entrain additional nutrients into the mixed layer but simultaneously reduce light availability. We suggest that in nutrient-depleted areas (south of 36°N) the added nutrients were a dominant factor increasing the chlorophyll a concentration, whereas in the nutrient-replete areas (north of 36°N), where phytoplankton growth was light limited, reduced light availability was the dominant factor determining reduced chlorophyll a concentration. Our results indicate that an increase in wind speed accompanied by precipitation events was a major contributor to the observed changes in chlorophyll a concentration during wet days, whereas the wet deposition of pollutant nitrogen slightly increased the chlorophyll a concentration (< 5%) only in nutrient-depleted areas.

show abstract

Enhancement of chlorophyll a production in Gulf Stream surface seawater by synthetic versus natural rain

Cited by 24 publications

References 29 publications

Biological and isotopic changes in coastal waters induced by Hurricane Gordon

Biological and isotopic changes in coastal waters induced by Hurricane Gordon

Impact of rainwater hydrogen peroxide on chlorophyll a content of surface Gulf Stream seawater off North Carolina, USA

Influence of precipitation events on phytoplankton biomass in coastal waters of the eastern United States

Contact Info

Product

Resources

About