Publications by Rebecca Murphy

IAN is committed to producing practical, user-centered communications that foster a better understanding of science and enable readers to pursue new opportunities in research, education, and environmental problem-solving. Our publications synthesize scientific findings using effective science communication techniques.

Adaptive monitoring for change: Record low hypoxia in Chesapeake Bay in 2023 (Page 1)

Adaptive monitoring for change: Record low hypoxia in Chesapeake Bay in 2023

Tango PJ, Zhang Q, Tian R, Murphy RR, Sullivan BM, Mallonee ME, Ghosh D, Goldfischer A, Gootman KS ·
2025

Seasonal hypoxia (dissolved oxygen [DO] levels ≤ 2 mg/l) poses a severe threat to coastal ecosystems globally, including the largest estuary in the United States, the Chesapeake Bay. This V-shaped drowned river valley features shallow flanks, where the deepest waters experience persistently low DO levels typically initiated during the spring and ending in late summer or early autumn. Reports on low DO conditions in the Chesapeake Bay date back over a century.

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Dissolved oxygen criteria attainment in Chesapeake Bay: Where has it improved since 1985?

Zhang Q, Murphy RR, Tian R, Gootman KS, Tango PJ. ·
2024

Many estuaries, including Chesapeake Bay, have suffered from undesirable conditions of algae blooms, poor water clarity, and low dissolved oxygen (DO). To better understand the status and trends of DO criteria attainment deficit (AD), we conducted a comprehensive assessment using monitoring data in the period of 1985–2022 and focused on the comparison of trends among 13 tidal systems.

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James Tributary Summary: A summary of trends in tidal water quality and associated factors, 1985-2021 (Page 1)

James Tributary Summary: A summary of trends in tidal water quality and associated factors, 1985-2021

Sullivan B, Gootman K, Gunnerson A, Johnson C, Mason C, Perry E, Bhatt G, Keisman J, Webber J, Harcum J, Lane M, Devereux O, Zhang Q, Murphy R, Karrh R, Butler T, Van Note V, Wei Z ·
3 November 2023

The James Tributary Summary outlines change over time for a suite of monitored tidal water quality parameters and associated potential drivers of those trends for the period 1985 – 2021 and provides a brief description of the current state of knowledge explaining these observed changes.

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Rise of Ruppia in Chesapeake Bay: Climate change–driven turnover of foundation species creates new threats and management opportunities (Page 1)

Rise of Ruppia in Chesapeake Bay: Climate change–driven turnover of foundation species creates new threats and management opportunities

Hensela MJS, Patricka CJ, Ortha RJ, Wilcoxa DJ, Dennison WC, Gurbiszc C , Hannamd MP, Landrye JB, Moorea KA, Murphyf RR , Testag JM, Wellerh DE, Lefchecki JS ·
2023

Global change has converted many structurally complex and ecologically and eco- nomically valuable coastlines to bare substrate. In the structural habitats that remain, climate-tolerant and opportunistic species are increasing in response to environmental extremes and variability. The shifting of dominant foundation species identity with climate change poses a unique conservation challenge because species vary in their responses to environmental stressors and to management.

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Nutrient limitation of phytoplankton in three tributaries of Chesapeake Bay: Detecting responses following nutrient reductions (Page 1)

Nutrient limitation of phytoplankton in three tributaries of Chesapeake Bay: Detecting responses following nutrient reductions

Zhang Q, Fisher TR,Buchanan C, Gustafson AB, Karrh RR, Murphy RR, Testa JM, Tian R, Tango PJ ·
2022

Many coastal ecosystems suffer from eutrophication, algal blooms, and dead zones due to excessive anthropogenic inputs of nitrogen (N) and phosphorus (P). This has led to regional restoration efforts that focus on managing watershed loads of N and P. In Chesapeake Bay, the largest estuary in the United States, dual nutrient reductions of N and P have been pursued since the 1980s.

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Data synthesis for environmental management: A case study of Chesapeake Bay (Page 1)

Data synthesis for environmental management: A case study of Chesapeake Bay

Orth RJ, Dennison WC, Wilcox DJ, Batiuk RA, Landry JB, Gurbisz C, Keisman J, Hannam M, Lefcheck JS, Murphy RR, Moore KA, Patrick CJ, Testa JM, Weller DE, Merrittj MF, Hobaugh P ·
2022

Synthesizing large, complex data sets to inform resource managers towards effective environmental stewardship is a universal challenge. In Chesapeake Bay, a well-studied and intensively monitored estuary in North America, the challenge of synthesizing data on water quality and land use as factors related to a key habitat, submerged aquatic vegetation, was tackled by a team of scientists and resource managers operating at multiple levels of governance (state, federal).

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Nutrient Improvements in Chesapeake Bay: Direct Effect of Load Reductions and Implications for Coastal Management (Page 1)

Nutrient improvements in Chesapeake Bay: Direct effect of load reductions and implications for coastal management

Murphy RR, Keisman J, Harcum J, Karrh RR, Lane M, Perry ES, Zhang Q ·
2022

In Chesapeake Bay in the United States, decades of management efforts have resulted in modest reductions of nutrient loads from the watershed, but the corresponding improvements in estuarine water quality have not consistently followed. Generalize additive models were used to directly link river flows and nutrient loads from the watershed to nutrient trends in the estuary on a station-by-station basis, which allowed for identification of exactly when and where responses are happening.

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Multi-scale trend analysis of water quality using error propagation of generalized additive models (Page 1)

Multi-scale trend analysis of water quality using error propagation of generalized additive models

Beck MW, Valpine PD, Murphy R, Wren I, Chelsky A, Foley M, Senn DB ·
2021

Effective stewardship of ecosystems to sustain current ecological status or mitigate impacts requires nuanced understanding of how conditions have changed over time in response to anthropogenic pressures and natural variability. Detecting and appropriately characterizing changes requires accurate and flexible trend assessment methods that can be readily applied to environmental monitoring datasets. A key requirement is complete propagation of uncertainty through the analysis.

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Nutrient Trends and Drivers in the Chesapeake Bay Watershed (Page 1)

Nutrient trends and drivers in the Chesapeake Bay watershed

Hyer KE, Phillips SW, Ator SW, Moyer DL, Webber JS, Felver R, Keisman JL, McDonnell LA, Murphy R, Trentacoste EM, Zhang Q, Dennison WC, Swanson S, Walsh B, Hawkey J, Taillie D ·
26 January 2021

The Chesapeake Bay Program maintains an extensive nontidal monitoring network, measuring nitrogen and phosphorus (nutrients) at more than 100 locations on rivers and streams in the watershed. Data from these locations are used by USGS to assess the ecosystem’s response to nutrient-reduction efforts.

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