Dual phosphorus and nitrogen nutrient reduction will be more effective than a phosphorus‐only reduction in mitigating diatom and cyanobacterial blooms in Lake Erie, USA–Canada DOI
Hans W. Paerl, Justin D. Chaffin,

J. M. Cheshire

et al.

Limnology and Oceanography, Journal Year: 2024, Volume and Issue: 69(12), P. 2913 - 2928

Published: Nov. 1, 2024

Lake Erie, USA-Canada, plays an important ecological and socioeconomic role but has suffered from chronic eutrophication. In particular, Western Erie (WLE) is the site of harmful algal blooms (HABs) which are suspected being driven by excessive nutrient (phosphorus (P) nitrogen (N)) inputs. During 2022 2023, in-situ dilution addition bioassays were conducted at a WLE bloom-impacted location to investigate whether reduction regime would be effective in limiting phytoplankton growth during June diatom-dominated spring August cyanobacteria-dominated summer blooms. The primary objectives this experiment 1) Determine if proposed 40% P-alone effectively reduce mitigate 2) assess reductions both P N more controlling biomass than exclusive either or P. Samples analyzed for concentrations rate responses specific groups utilizing diagnostic (for major groups) photopigments. Results indicated that although 20% dilutions led lower rates, effective. Our results support USA-Canada Great Lakes Water Quality Agreement recommendation reduction, also indicate parallel input most bloom magnitudes. Overall, our findings underscore year-round dual needed long-term control eutrophication blooms, including HABs diatoms, Erie.

Language: Английский

Nitrogen fixation may not alleviate stoichiometric imbalances that limit primary production in eutrophic lake ecosystems DOI Creative Commons
Isabelle M. Andersen, Jason M. Taylor, Patrick T. Kelly

et al.

Ecology, Journal Year: 2025, Volume and Issue: 106(1)

Published: Jan. 1, 2025

Abstract Ecosystem‐scale primary production may be proximately limited by nitrogen (N) but ultimately phosphorus (P) because N 2 fixation contributes new that accumulates relative to P at ecosystem scales. However, the duration needed transition between proximate limitation and ultimate remains unknown for most ecosystems, including lakes. Here we present results of a fully replicated, multi‐annual lake mesocosm experiment permitted full air‐water‐sediment interactions mimicked ecology. We manipulated supply achieve gradient N:P stoichiometry. Despite contributing as much 80% reactive in low treatments, phytoplankton biomass these treatments was not different from unfertilized controls. This suggests remained lowest even when substantial. Although fixed inputs reduced imbalance seasonally, did accumulate over multiple years. Additionally, readily high treatments. Instead, water column stoichiometry proportional experimental additions, suggesting strong influence external nutrient loading. Thus, found no evidence accumulation sufficient trigger seasonally or across our 3‐year experiment. Rather, indicate perpetuates eutrophic lakes, likely due export being its inputs. These findings offer insight regarding biogeochemical controls on their timeframe freshwater, marine, terrestrial ecosystems.

Language: Английский

Citations

0
Quantile regression Reveals phosphorous overwhelms nitrogen in controlling high chlorophyll-a concentration in freshwater lakes DOI

Haojie Han,

Xing Yan, Xiaohan Li

et al.

Journal of Hydrology, Journal Year: 2025, Volume and Issue: unknown, P. 132845 - 132845

Published: Feb. 1, 2025

Language: Английский

Citations

0
Phytoplankton group-specific and community responses to co-limiting nutrients in a managed reservoir: Lake Murray, South Carolina DOI

Haley Durbin,

A. J. Cain,

Gavin Madgett

et al.

Journal of Plankton Research, Journal Year: 2025, Volume and Issue: 47(2)

Published: Feb. 22, 2025

Abstract Eutrophication is increasingly becoming a problem for freshwater lakes. We evaluated the effects of additions nitrate (N as NO3−) and phosphate (P PO43−) on phytoplankton in temperate lake reservoir (Lake Murray, South Carolina). High-performance liquid chromatography ChemTax were used to measure concentrations microalgal groups 2021–2023 bioassays. The community during summer months consisted green algae (37%), diatoms (27%), cryptophytes (20%), cyanobacteria (11%) dinoflagellates (4%). Bioassays N (20-μM NaNO3), P (10-μM KH2PO4) + conducted monthly from April October 2023. All groups, except cyanobacteria, exhibited nutrient co-limitation with primary limiting nutrient. Similarly, co-limitation, but Nutrient (but not or singularly) also resulted significant shifts, strong response by algae. management implications this study are that increases loading ratio changes may result major toward dominance However, increasing relative promote cyanobacterial growth over other system.

Language: Английский

Citations

0
Phytoplankton and Zooplankton Community Dynamics in an Alpine Reservoir: Environmental Drivers and Ecological Implications in Daqing Reservoir, China DOI Open Access
Zheng Li, Ming Bai, Lei Yao

et al.

Water, Journal Year: 2025, Volume and Issue: 17(8), P. 1202 - 1202

Published: April 17, 2025

To elucidate the structural characteristics and environmental drivers of plankton communities in alpine reservoirs, we examined phytoplankton zooplankton Daqing Reservoir (China) across 13 sampling sites. Redundancy analysis (RDA) Pearson correlation were employed to explore relationships between density factors, as well diversity indices conditions. Key findings include: (1) A total 80 species identified, with Chlorophyta (37 species) dominant group, while 52 primarily represented by Rotifera. (2) Phytoplankton (Shannon: 3.07–4.21) suggested oligotrophic conditions, whereas 1.40–3.08) indicated meso- states. (3) RDA revealed that distribution was influenced chemical oxygen demand phosphorus, related ammonia nitrogen. These results highlight importance targeted nutrient management strategies protect water quality reservoirs.

Language: Английский

Citations

0
Dual nitrogen and phosphorus reductions are needed for long-term mitigation of eutrophication and harmful cyanobacterial blooms in the hydrologically-variable San Francisco Bay Delta, CA DOI
Hans W. Paerl, Haley E. Plaas, Leah Nelson

et al.

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 957, P. 177499 - 177499

Published: Nov. 15, 2024

Language: Английский

Citations

2
Dual phosphorus and nitrogen nutrient reduction will be more effective than a phosphorus‐only reduction in mitigating diatom and cyanobacterial blooms in Lake Erie, USA–Canada DOI
Hans W. Paerl, Justin D. Chaffin,

J. M. Cheshire

et al.

Limnology and Oceanography, Journal Year: 2024, Volume and Issue: 69(12), P. 2913 - 2928

Published: Nov. 1, 2024

Lake Erie, USA-Canada, plays an important ecological and socioeconomic role but has suffered from chronic eutrophication. In particular, Western Erie (WLE) is the site of harmful algal blooms (HABs) which are suspected being driven by excessive nutrient (phosphorus (P) nitrogen (N)) inputs. During 2022 2023, in-situ dilution addition bioassays were conducted at a WLE bloom-impacted location to investigate whether reduction regime would be effective in limiting phytoplankton growth during June diatom-dominated spring August cyanobacteria-dominated summer blooms. The primary objectives this experiment 1) Determine if proposed 40% P-alone effectively reduce mitigate 2) assess reductions both P N more controlling biomass than exclusive either or P. Samples analyzed for concentrations rate responses specific groups utilizing diagnostic (for major groups) photopigments. Results indicated that although 20% dilutions led lower rates, effective. Our results support USA-Canada Great Lakes Water Quality Agreement recommendation reduction, also indicate parallel input most bloom magnitudes. Overall, our findings underscore year-round dual needed long-term control eutrophication blooms, including HABs diatoms, Erie.

Language: Английский

Citations

1