Publication Date:
2024-03-15
Description:
Coastal ecosystems are prone to multiple anthropogenic and natural stressors including eutrophication, acidification, and invasive species. While the growth of some macroalgae can be promoted by excessive nutrient loading and/or elevated pCO2, responses differ among species and ecosystems. Native to the western Pacific Ocean, the filamentous, turf-forming rhodophyte, Dasysiphonia japonica, appeared in estuaries of the northeastern Atlantic Ocean during the 1980s and the northwestern Atlantic Ocean during the late 2000s. Here, we report on the southernmost expansion of the D. japonica in North America and the effects of elevated nutrients and elevated pCO2 on the growth of D. japonica over an annual cycle in Long Island, New York, USA. Growth limitation of the macroalga varied seasonally. During winter and spring, when water temperatures were 〈 15 °C, growth was significantly enhanced by elevated pCO2 (p 〈 0.05). During summer and fall, when the water temperature was 15–24 °C, growth was significantly higher under elevated nutrient treatments (p 〈 0.05). When temperatures reached 28 °C, the macroalga grew poorly and was unaffected by nutrients or pCO2. The delta 13C content of regional populations of D. japonica was −30 per mil, indicating the macroalga is an obligate CO2-user. This result, coupled with significantly increased growth under elevated pCO2 when temperatures were 〈 15 °C, indicates this macroalga is carbon-limited during colder months, when in situ pCO2 was significantly lower in Long Island estuaries compared to warmer months when estuaries are enriched in metabolically derived CO2. The delta 15N content of this macroalga (9 per mil) indicated it utilized wastewater-derived N and its N limitation during warmer months coincided with lower concentrations of dissolved inorganic N in the water column. Given the stimulatory effect of nutrients on this macroalga and that eutrophication can promote seasonally elevated pCO2, this study suggests that eutrophic estuaries subject to peak annual temperatures 〈 28 °C may be particularly vulnerable to future invasions of D. japonica as ocean acidification intensifies. Conversely, nutrient reductions would serve as a management approach that would make coastal regions more resilient to invasions by this macroalga.
Keywords:
Agardhiella subulata; Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Benthos; Bicarbonate ion; Bicarbonate ion, standard deviation; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calcite saturation state, standard deviation; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Calculated using seacarb after Orr et al. (2018); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, per tissue dry mass; Carbon, standard deviation; Carbon/Nitrogen ratio; Carbon/Nitrogen ratio, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, standard deviation; Coast and continental shelf; Dasysiphonia japonica; Event label; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Fugacity of carbon dioxide in seawater, standard deviation; Great_South_Bay; Growth/Morphology; Growth rate; Growth rate, standard deviation; Laboratory experiment; Macroalgae; Macro-nutrients; Month; Nitrogen, per tissue dry mass; Nitrogen, standard deviation; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; pH, standard deviation; Plantae; Porphyra purpurea; Registration number of species; Rhodophyta; Salinity; Salinity, standard deviation; Shinnecock_Bay; Single species; Species; Species interaction; Spectrophotometric; Temperate; Temperature, water; Temperature, water, standard deviation; Treatment; Type; Uniform resource locator/link to reference; δ13C; δ13C, standard deviation
Type:
Dataset
Format:
text/tab-separated-values, 3260 data points
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