Managing nitrogen legacies to accelerate water quality improvement

Nature Geoscience, Journal Year: 2022, Volume and Issue: 15(2), P. 97 - 105

Published: Feb. 1, 2022

Language: Английский

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Major point and nonpoint sources of nutrient pollution to surface water have declined throughout the Chesapeake Bay watershed

Environmental Research Communications, Journal Year: 2022, Volume and Issue: 4(4), P. 045012 - 045012

Published: March 14, 2022

Understanding drivers of water quality in local watersheds is the first step for implementing targeted restoration practices. Nutrient inventories can inform management decisions by identifying shifts nitrogen (N) and phosphorus (P) balances over space time while also keeping track likely urban agricultural point nonpoint sources pollution. The Chesapeake Bay Program's Assessment Scenario Tool (CAST) provides N P balance data counties throughout watershed, these were leveraged to create a detailed nutrient inventory all watershed from 1985-2019. This study focuses on three primary components-agricultural surplus, atmospheric deposition, source loads-which are thought be leading anthropogenic loading trends across watershed. All inputs, outputs, derived metrics (n=53) like surplus use efficiency, subjected short- long-term trend analyses discern how pollution surface have changed time. Across 1985-2019, downward deposition ubiquitous. Though there varying effects, declines observed, because nutrients being managed more efficiently. Multiple counties' loads declined, primarily associated with upgrades at major cities that discharge treated wastewater directly tidal waters. Despite positive developments, recent increases surpluses 2009-2019 highlight gains may soon reversed many areas basin. Besides tracking progress jurisdictional influence sources, used retrospective analysis past improvement/degradation decision makers develop their near- strategies.

Language: Английский

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A Random Forest in the Great Lakes: Stream Nutrient Concentrations Across the Transboundary Great Lakes Basin

Earth s Future, Journal Year: 2023, Volume and Issue: 11(4)

Published: April 1, 2023

Abstract Excess nutrient inputs from agricultural and urban sources have accelerated eutrophication increased the incidence of algal blooms in Great Lakes Basin (GLB). Lake basin management to address these threats relies on understanding key drivers pollution. Here, we use a random forest machine learning model leverage information 202 monitored streams GLB predict seasonal annual flow‐weighted concentrations nitrogen phosphorus, as well ratios across GLB. Land (agricultural land) land (tile drainage wetland density) emerge two most important predictors for dissolved inorganic (DIN; NO 3 − + 2 ) soluble reactive phosphorus (SRP; PO 4 ), while soil type density are more particulate P (PP). Partial dependence plots demonstrate increasing with tile decreasing density. In addition, livestock densities cover correspond higher SRP:Total Phosphorus (TP) ratios. Seasonally, highest proportions SRP occur summer fall. Higher also correlated N:P (DIN:TP) Livestock operations can contribute buildup nutrients excess manure application, subsurface provide transport pathways nutrients. Given that both SRP:TP strong harmful blooms, our study highlights importance management, restoration efforts intensively managed landscapes.

Language: Английский

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Advancing Watershed Legacy Nitrogen Modeling to Improve Global Water Quality

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(7), P. 2691 - 2697

Published: Feb. 17, 2023

Despite widespread implementation of watershed nitrogen reduction programs across the globe, levels in many surface waters remain high. Watershed legacy storage, i.e., long-term retention soils and groundwater, is one several explanations for this lack progress. However scientists water managers are ill-equipped to estimate how moderates in-stream responses land conservation practices, largely because modeling tools associated monitoring approaches answering these questions inadequate. We demonstrate need improved models simulate processes offer solutions support nitrogen-based sustainable management globe.

Language: Английский

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Long-term annual soil nitrogen surplus across Europe (1850–2019)

Scientific Data, Journal Year: 2022, Volume and Issue: 9(1)

Published: Oct. 10, 2022

Abstract Worldwide surface waters suffer from the presence of nitrogen (N) compounds causing eutrophication and deterioration water quality. Despite many Europe-wide legislation’s, we still observe high N levels across bodies in Europe. Information on long-term annual soil surplus is needed to better understand these inform future management strategies. Here, reconstructed analysed for both agricultural non-agricultural soils Europe at a 5 arcmin (≈10 km equator) spatial resolution more than century (1850–2019). The dataset consists 16 estimates that account uncertainties resulting input data sources methodological choices major components surplus. We documented consistency plausibility our by comparing them with previous studies discussed about possible avenues further improvements. Importantly, offers flexibility aggregating any scale relevance support land

Language: Английский

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Progress in reducing nutrient and sediment loads to Chesapeake Bay: Three decades of monitoring data and implications for restoring complex ecosystems

Wiley Interdisciplinary Reviews Water, Journal Year: 2023, Volume and Issue: 10(5)

Published: June 6, 2023

Abstract For over three decades, Chesapeake Bay (USA) has been the focal point of a coordinated restoration strategy implemented through partnership governmental and nongovernmental entities, which classical model for coastal worldwide. This synthesis aims to provide resource managers estuarine scientists with clearer perspective magnitude changes in water quality within watershed, including nitrogen (N), phosphorus (P), sediment River Input Monitoring (RIM) watershed unmonitored below‐RIM watershed. The flow‐normalized N load from RIM declined period 1985–2017, but P loads have lacked progress. Reductions riverine are largely driven by reductions sources atmospheric deposition. Future will require significant progress managing agricultural nonpoint sources. comprises disproportionately high fraction inputs Bay, shown long‐term declines major sources, (N P), deposition manure P) fertilizer based on combination monitoring modeling assessments. To date, cleanup efforts achieved some toward reducing nutrients resulted improving estuary. However, further critical achieve Total Maximum Daily Load goals, emerging challenges due Conowingo Reservoir, legacy nutrients, climate change, population growth should be considered. Continued monitoring, modeling, assessment critically important informing this complex ecosystem. article is categorized under: Science Water > Quality Life Stresses Pressures Ecosystems Conservation, Management, Awareness

Language: Английский

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Characterizing legacy nitrogen-induced time lags in riverine nitrogen reduction for the Songhuajiang River Basin: Source analysis, spatio-seasonal patterns, and impacts on future water quality improvement

Water Research, Journal Year: 2023, Volume and Issue: 242, P. 120292 - 120292

Published: June 29, 2023

Language: Английский

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Integrating monitoring and modeling information to develop an indicator of watershed progress toward nutrient reduction goals

Ecological Indicators, Journal Year: 2024, Volume and Issue: 158, P. 111357 - 111357

Published: Jan. 1, 2024

Eutrophication has been a major environmental issue in many coastal and inland ecosystems, which is primarily attributed to excessive anthropogenic inputs of nutrients. Restoration efforts have therefore focused on the reduction watershed nutrient loads, including Chesapeake Bay (USA). To facilitate management, models are often developed used assess expected impact scenarios past future management policies practices conditions. However, level load reductions estimated using monitoring data does not match with model predictions, may cast doubt effectiveness restoration efforts, reliability model, prospect achieving pre-established goals. better reconcile such inconsistencies between expectation (i.e., modeling estimates) reality information), watershed-wide indicator was for explicitly quantify progress toward goals context Total Maximum Daily Load (TMDL). Results show that since 1995 long-term made TMDL planning targets both nitrogen phosphorus. Specifically, implemented realized (in data) increasing over time, whereas need be meet decreasing. In addition, meeting varied source sectors locations: i.e., point fully or nearly implemented, nonpoint by 50%-70%. summary, this indicator, largely based data, can provide at least four benefits: (1) evaluating validity modeled estimates comparing them information; (2) placing monitored riverine trends into context; (3) different locations; (4) facilitating communication Program Partnership public. Although we focus development interpretation watershed, framework transferred watersheds within beyond where similar information exists, gauge expectations trajectory pace

Language: Английский

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Long‐Term Mississippi River Trends Expose Shifts in the River Load Response to Watershed Nutrient Balances Between 1975 and 2017

Water Resources Research, Journal Year: 2021, Volume and Issue: 57(11)

Published: Nov. 1, 2021

Excess nutrients transported by the Mississippi River (MR) contribute to hypoxia in Gulf of Mexico. Nutrient balances are key drivers river nutrient loads and represent inputs (fertilizer, manure, deposition, wastewater, N-fixation, weathering) minus outputs (nutrient uptake removal harvest, N emissions). Here, we quantified annual changes nitrogen (N) phosphorus (P) at MR Outlet documented that load response watershed shifted between 1975 2017. Annual were positively correlated 1985, but after, a disconnect both P emerged, subsequent patterns different for versus P. We evaluated relative impacts legacy other latent factors, which data not available, on trends. Our analysis showed case N, factors potentially just as important explaining over time balances, P, they even more important. hypothesized these included implementation best management practices, buffering capacity, effects tile drainage, or increased precipitation. analytical approach shows promise investigation water quality trends well-represented typical national scale geospatial datasets.

Language: Английский

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Regional patterns and drivers of total nitrogen trends in the Chesapeake Bay watershed: Insights from machine learning approaches and management implications

Water Research, Journal Year: 2022, Volume and Issue: 218, P. 118443 - 118443

Published: April 9, 2022

Language: Английский

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