Nutrient and sediment transport exhibit strong spatial and temporal inequality, with a small percentage of locations and events contributing to the vast majority of total annual loads. The processes for determining how to reduce total annual loads at a watershed scale often target spatial, but not temporal, components of inequality.

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Novel forms of drought are emerging globally, due to climate change, shifting teleconnection patterns, expanding human water use, and a history of human influence on the environment that increases the probability of transformational ecological impacts. These costly ecological impacts cascade to human communities, and understanding this changing drought landscape is one of today’s grand challenges.

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The Chester River, a tributary of Chesapeake Bay, provides critical habitats for numerous living species and oyster aquaculture, but faces increasing anthropogenic stresses due to excessive nutrient loading and hypoxia occurrence.

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Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal … wetlands are complex social-ecological systems that occur at all latitudes, from polar … regions to the tropics. This overview covers wetlands in five continents. The wetlands … are of varying size, catchment size, human population and stages of economic … development.

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Excessive nitrogen (N) inputs to coastal waters can lead to severe eutrophication and different chemical forms of N exhibit varying levels of effectiveness in fueling primary production. Efforts to mitigate N fluxes from coastal watersheds are often guided by models that predict changes in N loads as a function of changes in land use, management practices, and climate. However, relatively little is known on the impacts of such changes on the relative fractions of different N forms.

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This review aims to synthesize the current knowledge of sediment dynamics using insights from long-term research conducted in the watershed draining to the Chesapeake Bay, the largest estuary in the U.S., to inform management actions to restore the estuary and its watershed. The sediment dynamics of the Chesapeake are typical of many impaired watersheds and estuaries around the world, and this synthesis is intended to be relevant and transferable to other sediment-impaired systems.

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The process of developing a socioenvironmental report card through transdisciplinary collaboration can be used in any system and can provide the foundation for collaborative solutions for sustainable resource management by creating a holistic assessment that balances environmental, economic, and social concerns that incorporates multiple perspectives from multisectoral actors.

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Controlling phosphorus is fundamental to limit the risk of eutrophication of continental aquatic ecosystems. Integrated modelling of its concentration in the aquatic continuum requires specific tools for water bodies. However, although simple static empirical models and complex biogeochemical models are numerous, there are few relatively simple and flexible models able to simulate seasonal variations in phosphorus concentrations in water bodies and particularly in reservoirs.

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Human activities can elevate coastal levels of dissolved inorganic nitrogen (DIN). As macroalgae readily absorb and accumulate DIN, the elemental (total N and C:N ratio) composition of their tissues is less affected by temporal fluctuations compared to more direct measures of DIN concentration. Additionally, their isotopic (δ15N) composition can reflect that of the source, which could potentially be used to identify between multiple effluent sources.

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Accurate quantification of riverine water‐quality concentration and flux is challenging because monitoring programs typically collect concentration data at lower frequencies than discharge data. Statistical methods are often used to estimate concentration and flux on days without observations. One recently developed approach is the Weighted Regressions on Time, Discharge, and Season (WRTDS), which has been shown to provide among the most accurate estimates compared to other common methods.

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