Article
Ecology
Nasrin Nikafkar, Younos Vakil Alroaia, Seyyed Abdollah Heydariyeh, Anton J. Schleiss
Summary: Improper use of chemical fertilizers has led to land degradation. Organic crops, farmed using organic fertilizers, are considered an alternative solution to develop the ecosystem health and improve the soil. This research aimed to study the feasibility of reusing dam reservoir sediments as organic fertilizers to revitalize agricultural soil on a commercial scale.
ECOLOGICAL ECONOMICS
(2023)
Review
Environmental Sciences
Mathias Kondolf, Jaeeung Yi
Summary: Dams are important to society but have significant environmental impacts. Sedimentation poses a threat to the sustainability of reservoir storage. Dam renovation, including structural retrofits, fishway retrofits, reservoir reoperation, and sustainable sediment management, is crucial to address environmental concerns and ensure dam sustainability. Dam removal, although discussed frequently, is not a practical solution for most dams.
Article
Engineering, Civil
Mahmood M. Al-Mamari, Sameh A. Kantoush, Tahani M. Al-Harrasi, Ali Al-Maktoumi, Karim I. Abdrabo, Mohamed Saber, Tetsuya Sumi
Summary: Soil erosion and sediment transportation in arid regions can cause reservoir storage losses and degradation of downstream channels. However, the lack of data and a formula for sediment yield calculation has hindered reservoir management. This study aimed to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE) with remote sensing data. The sediment trapped in the Assarin Dam reservoir was estimated using UAV surveys and photogrammetry analysis. The results can support reservoir management practices and demonstrate the suitability of UAV-based photogrammetry for measuring trapped sediment volumes.
JOURNAL OF HYDROLOGY
(2023)
Article
Environmental Sciences
W. R. Boynton, M. A. C. Ceballos, C. L. S. Hodgkins, D. Liang, J. M. Testa
Summary: This study conducted measurements of sediment-water fluxes in Chesapeake Bay and Maryland Coastal Bays, and analyzed the primary controlling factors and relative contribution of sediment-water fluxes to nutrient cycling. Hotspots for sediment-water fluxes were identified, and statistical models showed that temperature, bottom water oxygen and nutrient concentration, and sediment organic matter were important controlling variables. Long-term variations in fluxes exhibited weak evidence of trends, while interannual variability was related to water column and sediment variables. Additionally, the importance of recycled nutrients in these shallow systems was revealed.
ESTUARIES AND COASTS
(2023)
Article
Environmental Sciences
Kristina G. Hopkins, Jacqueline S. Welles, Emily J. Pindilli, Gregory B. Noe, Peter R. Claggett, Labeeb Ahmed, Marina J. Metes
Summary: Floodplains provide critical ecosystem services by regulating floodwaters and retaining sediments and nutrients. A study was conducted to quantify the services that floodplains provide to downstream communities within the Chesapeake Bay and Delaware River watersheds. The study included the quantification and valuation of sediment and nutrient retention, as well as flood regulation services provided by floodplains.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Geosciences, Multidisciplinary
Shi Ren, Bangwen Zhang, Wei-Jie Wang, Yuan Yuan, Chao Guo
Summary: Through measures like upstream sediment trapping and sediment peak regulation, the incoming sediment load of TGR has been significantly reduced, successfully addressing sedimentation issues and providing valuable lessons for reservoir management elsewhere.
Article
Geosciences, Multidisciplinary
Kazimierz Banasik, Leszek Hejduk, Adam Krajewski, Michal Wasilewicz
Summary: The study compared the sediment deposited in a small reservoir in Poland with estimates of sediment yield from its catchment. Results showed a decreasing trend in sediment deposition in the reservoir over four different periods.
Article
Environmental Sciences
C. Krahforst, L. A. Sherman, K. Kehm
Summary: Trace metals in sediments from the Chester River were investigated to understand their distributions and potential sources. The concentrations of lead, arsenic, nickel, chromium, and copper exceeded sediment toxicity guidelines in a significant proportion of samples. Enrichment factors for cadmium, silver, lead, arsenic, and zinc were elevated above natural background levels. Nickel, copper, zinc, and cadmium showed significant differences in enrichment factors between different segments of the river. Cadmium and arsenic enrichments were most likely from the application of fertilizers in the watershed, while active marinas were identified as important sources of metal enrichment, especially for copper.
MARINE POLLUTION BULLETIN
(2022)
Article
Environmental Sciences
Klajdi Sotiri, Stephan Hilgert, Michael Mannich, Tobias Bleninger, Stephan Fuchs
Summary: Siltation directly reduces the usable water amount in reservoirs, posing a significant challenge in the 21st century. Assessing sediment volume and distribution accurately requires considering multiple measurement techniques.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Engineering, Environmental
Ngoc-Diep Nguyen, Marion Rabiet, Malgorzata Grybos, Veronique Deluchat
Summary: Anoxia in reservoirs leads to the release of phosphorus into the water, supporting eutrophication. This study investigated the release of colloidal and truly dissolved fractions of sedimentary phosphorus under different oxygen conditions. The results showed that anoxic conditions caused a large release of colloidal phosphorus, while oxic conditions led to a limited release of both colloidal and truly dissolved phosphorus. The dynamics of phosphorus were mainly influenced by the reductive dissolution of iron and the release of organic matter.
Article
Environmental Sciences
Camila Bergmann Goulart, Tobias Bleninger, Hugo de Oliveira Fagundes, Fernando Mainardi Fan
Summary: The construction of dams or barrages can affect the watercourse and the retention of sediment from the river, causing siltation of the reservoir and obstruction of water intakes. However, there is limited information on sediment management, transport equations, and parameters associated with numerical modeling of sediment management. This study evaluates the effects of different parameters on sediment management in reservoirs and highlights the importance of proper estimation of model parameters for accurate predictions.
INTERNATIONAL JOURNAL OF SEDIMENT RESEARCH
(2023)
Article
Environmental Sciences
Yuan Niu, Farhed A. Shah
Summary: This study focuses on the economic impact of sedimentation on dams and developing a model to optimize the initial reservoir size for maximizing net benefits over the lifespan of the dam. It also considers the costs of sediment management and decommissioning in order to provide a comprehensive understanding of optimal dam sizing under different circumstances.
WATER RESOURCES RESEARCH
(2021)
Article
Environmental Sciences
Shufen Pan, Zihao Bian, Hanqin Tian, Yuanzhi Yao, Raymond G. Najjar, Marjorie A. M. Friedrichs, Eileen E. Hofmann, Rongting Xu, Bowen Zhang
Summary: This study examined nitrogen export from the Chesapeake Bay watershed since 1900 and found that the export of ammonium and nitrate increased until the 1990s and then declined. Precipitation was the primary driver of interannual variability in nitrogen export, while wastewater discharge explained most of the long-term changes in ammonium and organic nitrogen fluxes. Atmospheric deposition, wastewater, and synthetic fertilizer were responsible for the trend of nitrate export. Management of terrestrial non-point source nutrients will be crucial in achieving water quality goals.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2021)
Article
Biotechnology & Applied Microbiology
Yu Qin, Qiong Tang, Lunhui Lu, Yuchun Wang, Irina Izaguirre, Zhe Li
Summary: This study investigated the temporal distribution patterns of bacterial communities in a transition section of the Three Gorges Reservoir, revealing that sediment bacteria dominate the reservoir microbial communities. Differences were found in bacterial diversity between water and sediment, with bacterioplankton communities showing greater sensitivity to monthly changes.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2021)
Article
Engineering, Civil
Bangwen Zhang, Baosheng Wu, Ruoyin Zhang, Shi Ren, Minhui Li
Summary: The study focused on the asynchronous propagation characteristics of flood and sediment peaks downstream in the Three Gorges Reservoir (TGR) by using a 3D numerical model. The model accurately reproduced the processes of flood propagation and sediment transport during the 2013 flood season, with the horizontal grid having a greater influence on the results than the vertical grid. The impounded level in the TGR had a significant impact on the occurrence time and magnitude of the sediment peak, with the time of sediment peak lagging behind flood peak increasing as the impounded level increased.
JOURNAL OF HYDROLOGY
(2021)
Article
Ecology
Qian Zhang, Joel D. Blomquist, Douglas L. Moyer, Jeffrey G. Chanat
FRONTIERS IN ECOLOGY AND EVOLUTION
(2019)
Article
Limnology
Vincent Roubeix, Camille Minaudo, Jordi Prats, Nathalie Reynaud, Qian Zhang, Florentina Moatar, Pierre-Alain Danis
Review
Environmental Sciences
Gregory B. Noe, Matthew J. Cashman, Katie Skalak, Allen Gellis, Kristina G. Hopkins, Doug Moyer, James Webber, Adam Benthem, Kelly Maloney, John Brakebill, Andrew Sekellick, Mike Langland, Qian Zhang, Gary Shenk, Jeni Keisman, Cliff Hupp
WILEY INTERDISCIPLINARY REVIEWS-WATER
(2020)
Article
Environmental Sciences
Heather E. Preisendanz, Tamie L. Veith, Qian Zhang, James Shortle
Summary: The study reveals significant temporal inequality in nutrient and sediment transport across the Chesapeake Bay watershed, with greater inequality for total phosphorus and total suspended sediment compared to total nitrogen and flow. These findings emphasize the importance of targeting specific time periods and flow conditions to achieve load reduction goals in impaired watersheds. The proposed 'temporal targeting framework' provides a useful and convenient method for watershed planners to create load targeting tables specific to a watershed and constituent.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Engineering, Environmental
Qian Zhang, Thomas R. Fisher, Emily M. Trentacoste, Claire Buchanan, Anne B. Gustafson, Renee Karrh, Rebecca R. Murphy, Jennifer Keisman, Cuiyin Wu, Richard Tian, Jeremy M. Testa, Peter J. Tango
Summary: Understanding the temporal and spatial roles of nutrient limitation is crucial for successful management strategies in Chesapeake Bay. Analysis of historical data shows expanded areas of nitrogen limitation and reduced nutrient saturation in response to long-term reductions in nitrogen load. However, nutrient limitation patterns remain largely unchanged in the majority of the mainstem, indicating the need for further reduction in nutrient loads to achieve a less nutrient-saturated ecosystem.
Article
Environmental Sciences
Qian Zhang, James S. Webber, Douglas L. Moyer, Jeffrey G. Chanat
Summary: The FN2Q approach is an extension of the flow-normalization procedure of the well-established WRTDS method, providing daily estimates of low-flow and high-flow FN flux for summarizing trends in river water quality. Application of the method to the South Fork Shenandoah River shows a decline in total nitrogen flux, primarily driven by a decrease in low-flow class, which is correlated with wastewater effluent loads. The high-flow flux exhibited a spike around 2007, likely due to increased delivery of particulate nitrogen associated with sediment transport.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
S. Y. Chang, Q. Zhang, D. K. Byrnes, N. B. Basu, K. J. Van Meter
Summary: Efforts to reduce nitrogen inputs in the Chesapeake Bay have shown some progress, with recent improvements in water quality attributed to decreases in nitrogen surplus magnitudes. Despite slow improvement, goals to reduce nitrogen loads by 25% across the region may be met within the next two decades even with no additional changes in current management practices. Time lags in achieving water quality goals may vary across different watersheds, with the longest delays seen in highly agricultural areas where legacy nitrogen continues to impact water quality.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Engineering, Environmental
Rebecca R. Murphy, Jennifer Keisman, Jon Harcum, Renee R. Karrh, Mike Lane, Elgin S. Perry, Qian Zhang
Summary: The study finds that nutrient loads in Chesapeake Bay are mostly improving after accounting for variations in freshwater flow, with reductions from nearby point sources slightly more effective in explaining estuarine nutrient trends than reductions from rivers. Both types of loads from multiple locations across the watershed are together necessary and responsible for the improving estuarine nutrient conditions.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Qian Zhang, Joel T. Bostic, Robert D. Sabo
Summary: This study combines clustering and classification methods to investigate the regional patterns and drivers of total nitrogen trends in the Chesapeake Bay Non-Tidal Monitoring Network. Results show that improved agricultural nutrient management has led to declines in agricultural nonpoint sources and water-quality improvement. The developed models are also used to predict fine spatial information for the entire Chesapeake Bay watershed, facilitating targeted watershed management.
Article
Environmental Sciences
Robert D. Sabo, Breck Sullivan, Cuiyin Wu, Emily Trentacoste, Qian Zhang, Gary W. Shenk, Gopal Bhatt, Lewis C. Linker
Summary: Understanding the drivers of water quality in local watersheds is crucial for targeted restoration practices. This study examines the nutrient balance components and their trends, such as agricultural surplus, atmospheric deposition, and point source loads, to identify the leading drivers of nutrient loading trends in the Chesapeake Bay watershed. The study finds that while there have been positive developments in reducing pollution sources, recent increases in agricultural surpluses indicate potential reversals in water quality gains.
ENVIRONMENTAL RESEARCH COMMUNICATIONS
(2022)
Article
Biodiversity Conservation
A. R. Zahran, Q. Zhang, P. Tango, E. P. Smith
Summary: This paper develops a barometer that indexes water quality in the Chesapeake Bay and summarizes it over spatial regions and temporal periods. The barometer is based on risk assessment and hydrology, and calculates three different metrics of water quality relative to numerical criteria. The barometer score is a geometric mean of these three metrics. The paper evaluates water quality using dissolved oxygen measurements collected in the Chesapeake Bay during the summer seasons from 1985 to 2020, and reports the barometer score at different levels.
ECOLOGICAL INDICATORS
(2022)
Article
Engineering, Environmental
Qian Zhang, Thomas R. Fisher, Claire Buchanan, Anne B. Gustafson, Renee R. Karrh, Rebecca R. Murphy, Jeremy M. Testa, Richard Tian, Peter J. Tango
Summary: Analyzing historical data from the Chesapeake Bay's tidal tributaries revealed enhanced nutrient limitation at four of the six stations, indicating long-term water quality improvements. This research presents a new analytical tool for detecting signs of ecosystem recovery following nutrient reductions.
Article
Environmental Sciences
Qian Zhang, Joel D. Blomquist, Rosemary M. Fanelli, Jennifer L. D. Keisman, Douglas L. Moyer, Michael J. Langland
Summary: From 1985 to 2017, the nitrogen load in Chesapeake Bay has decreased, but the phosphorus and sediment loads have not improved. Future efforts should focus on managing agricultural nonpoint sources. Although the water quality in Chesapeake Bay has improved, further reductions are necessary to meet the goals.
WILEY INTERDISCIPLINARY REVIEWS-WATER
(2023)
Article
Environmental Sciences
Jinzhao Xiang, Tingwei Cui, Xuyan Li, Qian Zhang, Bing Mu, Rongjie Liu, Wenjing Zhao
Summary: This study quantitatively evaluated the impact of a 3-year pollution control action on water quality in the Bohai Sea using satellite observations. The results showed a significant improvement in water quality during the action period, with clearer and bluer water. The study highlights the important role of satellite remote sensing in coastal ecosystem management.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Ryan E. Langendorf, Vyacheslav Lyubchich, Jeremy M. Testa, Qian Zhang
Summary: This study demonstrates the use of environmental monitoring programs to better understand and manage complex ecosystems, using surface water dissolved oxygen criteria attainment in the Chesapeake Bay as a case study. The research revealed contrasting controls on dissolved oxygen across different regions, with factors such as summer freshwater and sediment inputs impacting attainment differently in landward and open waters, and algae biomass showing opposite effects in surface and deep waters.