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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Many coastal ecosystems have suffered from cultural eutrophication and dead zones. In the Chesapeake Bay, water quality degradation is manifested in low dissolved oxygen, poor water clarity, and decreased submerged aquatic vegetation acreage.

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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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Evaluating the real-world impacts of proposed restoration strategies is a complex process. Typically, restoration is pursued to achieve a number of primary and secondary objectives as most coastal and deltaic areas support a variety of functions and activities with substantial social and economic values. In this analysis, we demonstrate the importance of considering the broad implications of planning and implementing restoration projects.

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Oxygen depletion in coastal waters is increasing globally due primarily to eutrophication and warming. Hypoxia responses to nutrient loading and climate change have been extensively studied in large systems like the Chesapeake Bay and the Baltic Sea, while fewer studies have investigated smaller, shallower hypoxic zones.

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Scientific working groups bring together experts from different disciplines and perspectives to tackle the “wicked problems” facing natural systems and society. Yet participants can feel overwhelmed or inadequate in groups within academic environments, which tends to be most acute at early career stages and in people from systematically marginalized backgrounds.

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Countries are expanding marine protected area (MPA) networks to mitigate fisheries declines and support marine biodiversity. However, MPA impact evaluations typically assess total fish biomass. Here, we examine how fish biomass disaggregated by adult and juvenile life stages responds to environmental drivers, including sea surface temperature (SST) anomalies and human footprint, and multiple management types at 139 reef sites in the Mesoamerican Reef (MAR) region.

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This conference report synthesises the discussions and lessons learnt from a workshop with international and local experts and practitioners held in Noum´ea, New Caledonia (France, Oceania) from 17th to 21st of October 2022. The workshop was part of a larger transdisciplinary process aimed to anticipate and react to marine heatwaves, coastal erosion and sea level rise as well as ocean deoxygenation and acidification in Fiji and New Caledonia.

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Many agricultural watersheds rely on the voluntary use of management practices (MPs) to reduce nonpoint source nutrient and sediment loads; however, the water-quality effects of MPs are uncertain. We interpreted water-quality responses from as early as 1985 through 2020 in three agricultural Chesapeake Bay watersheds that were prioritized for MP implementation, namely, the Smith Creek (Virginia), Upper Chester River (Maryland), and Conewago Creek (Pennsylvania) watersheds.

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This research assesses Chesapeake Bay’s sustainability in four domains: environment, social, economy, and governance, using the Circles of Coastal Sustainability methodology. Each of the four domains has five categories, and each category is evaluated by the authors’ expert judgment using indicators related to the socio-ecological system and the definition of sustainable development.

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