Quantifying seasonal to multi-decadal signals in coastal water quality using high- and low-frequency time series data

Cambridge Prisms Coastal Futures, Journal Year: 2024, Volume and Issue: 2

Published: Jan. 1, 2024

Abstract To inform water quality monitoring techniques and modeling at coastal research sites, this study investigated seasonality trends in lagoons on the eastern shore of Virginia, USA. Seasonality was quantified with harmonic analysis low-frequency time-series, approximately 30 years quarterly sampled data thirteen mainland, lagoon, ocean inlet along 4–6 high-frequency, 15-min resolution sonde two mainland sites. Temperature, dissolved oxygen, apparent oxygen utilization (AOU) were dominated by annual harmonics, while salinity chlorophyll- a exhibited mixed semi-annual harmonics. Mainland sites had larger seasonal amplitudes higher peak summer values for temperature, AOU, likely from longer residence times, shallower waters, proximity to marshes uplands. Based statistical subsampling high-frequency data, one several decades (at sampling) needed quantify climatological cycle within specified confidence intervals. Statistically significant decadal warming increasing concentrations found sub-set no distinct geographic patterns other trends. The highlighted challenges detecting long-term low frequency large interannual variability.

Language: Английский

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Unexpected stability in faunal population abundances following an estuary‐wide collapse of oysters

Ecosphere, Journal Year: 2024, Volume and Issue: 15(8)

Published: Aug. 1, 2024

Abstract Live oyster reefs are considered a critical recruitment habitat for estuarine faunal populations as localized in situ or mesocosm studies have demonstrated many species prefer live habitat. It has therefore been assumed that the loss of would precipitate population declines, but this largely untested at large (estuary) scales. Here, we assessed how estuary‐wide were affected by 95% following 2012 collapse Apalachicola Bay, FL, which previously supported one largest fisheries United States. We standardized long‐term fisheries‐independent monitoring seine and trawl data to create relative indices resident, associated, transient species' overall abundance recruit (restrictive sizes between 15% 35% ). expected both decrease collapse, particularly among reside on reefs. However, analyses via series one‐sided Bayesian t tests did not indicate significantly declined post‐collapse. As response could be lagged also conducted change point search declines. Of 24 time series, only two had significant points post‐collapse, black sea bass with an associated end series. The surprising paucity decline may due use alternative types, exceptionally responses, or, perhaps most compelling, disconnect preferred required habitats. Our failure detect consequences suggests assumptions (or restoration) effects fauna ecosystem scales straightforward extrapolation sub‐estuary‐scale result poor predictions future outcomes.

Language: Английский

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Predictors of outplanted marine bivalve survival in restoration: A review and synthesis

Journal of Applied Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 22, 2024

Abstract Global declines in marine shellfish have resulted widespread efforts to restore populations. Previous research has predominantly focused on substrate‐limited rather than recruitment‐limited systems, yet given increased use of aquaculture‐produced stock bivalves, there is a need understand differences the survival hatchery‐produced and translocated wild stock. We conducted systematic review synthesis studies that quantified outplanted bivalves. The identified 893 unique stocking events across 111 for 29 species 10 families. Most occurred temperate regions (73%), four bivalve families (Ostreidae 37%, Pectinidae 20%, Veneridae 16% Mytilidae 11%). More stockings (66%) (34%). quantitative analyses five determine how origin, size at outplant, outplant density, substrate co‐deployment, predator exclusion time since influences survival. Survival consistently decreased through all species. Substrate origin did not influence survival, while density affected some Synthesis applications . Our broadly demonstrate variability bivalves time, however predicted was poor after 2 years (<3%). Generally low highlights difficulties associated with conducting scalable restoration systems. Based our findings, using stock, mitigating predation outplanting epifaunal high densities may increase probabilities when restoration. Further exploration needed whether results similar ecosystem structure, function, service provisioning natural restored reefs

Language: Английский

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Collapsed oyster populations in large Florida estuaries appear resistant to restoration using traditional cultching methods—Insights from ongoing efforts in multiple systems

Marine and Coastal Fisheries, Journal Year: 2023, Volume and Issue: 15(5)

Published: Oct. 1, 2023

Abstract Objective Depressed eastern oyster Crassostrea virginica populations in the northern Gulf of Mexico have been target numerous post‐ Deepwater Horizon restoration projects. These projects primarily focused on replacing cultch (substrate) to promote spat settlement, increase recruitment, and bolster adult populations. This study assessed outcomes six such efforts, which used different types densities between 2015 2022 three estuaries Florida panhandle (Pensacola, St. Andrew, Apalachicola bays). Total costs for these were more than US$14 million. Methods Using generalized linear models, we analyzed count data collected from diver surveys size‐classes (spat, seed, adult). We tested whether population responses efforts varied over time, location, or design. Result Oyster counts did not persistently after restoration, regardless type density. Positive irregular short‐lived seemed only occur spat‐size oysters immediately restoration. None significantly improved abundance any size‐class estuaries. Factors contributing results likely include design implementation elements, as materials height restored reefs. However, monitoring programs able deliver a clear picture what is hindering success. Conclusion For succeed, changes are needed—both their way they monitored—in order continuous learning improvement outcomes.

Language: Английский

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DNA methylation modulates transcriptional noise in response to elevated pCO₂in the eastern oyster (Crassostrea virginica)

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: April 8, 2024

Ocean acidification significantly affects marine calcifiers like oysters, warranting the study of molecular mechanisms DNA methylation that contribute to adaptive plasticity in response environmental change. However, a consensus has not been reached on extent which modules gene expression, and turn plasticity, invertebrates. In this study, we investigated impact pCO 2 expression eastern oyster, Crassostrea virginica . After 30-day exposure control (572 ppm) or elevated (2,827 ppm), whole genome bisulfite sequencing (WGBS) RNA-Seq data were generated from adult female gonad tissue male sperm samples. Although differentially methylated loci (DML) identified females (89) males (2,916), there no expressed genes, only one transcript females. body impacted other forms activity sperm, such as maximum number transcripts per changes predominant expressed. Elevated increased variability (transcriptional noise) but decreased noise females, suggesting sex-specific role regulation. Functional annotation genes with transcript-level containing DML revealed several enriched biological processes potentially involved response, including apoptotic pathways signal transduction, well reproductive functions. Taken together, these results suggest may regulate maintain homeostasis conditions could play key resilience

Language: Английский

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