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Feng S, Wang M, Heal MR, Liu X, Liu X, Zhao Y, Strokal M, Kroeze C, Zhang F, Xu W. The impact of emissions controls on atmospheric nitrogen inputs to Chinese river basins highlights the urgency of ammonia abatement. SCIENCE ADVANCES 2024; 10:eadp2558. [PMID: 39259806 DOI: 10.1126/sciadv.adp2558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Accepted: 08/02/2024] [Indexed: 09/13/2024]
Abstract
Excessive nitrogen (N) deposition affects aquatic ecosystems worldwide, but effectiveness of emissions controls and their impact on water pollution remains uncertain. In this modeling study, we assess historical and future N deposition trends in Chinese river basins and their contributions to water pollution via direct and indirect N deposition (the latter referring to transport of N to water from N deposited on land). The control of acid gas emissions (i.e., nitrogen oxides and sulfur dioxide) has had limited effectiveness in reducing total N deposition, with notable contributions from agricultural reduced N deposition. Despite increasing controls on acid gas emissions between 2011 and 2019, N inputs to rivers increased by 3%, primarily through indirect deposition. Simultaneously controlling acid gas and ammonia emissions could reduce N deposition and water inputs by 56 and 47%, respectively, by 2050 compared to 2019. Our findings underscore the importance of agricultural ammonia mitigation in protecting water bodies.
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Affiliation(s)
- Sijie Feng
- State Key Laboratory of Nutrient Use and Management, College of Resources and Environmental Sciences, Key Laboratory of Plant-Soil Interactions, Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing 100193, China
- Earth Systems and Global Change Group, Wageningen University & Research, Wageningen 6708 PB, Netherlands
| | - Mengru Wang
- Earth Systems and Global Change Group, Wageningen University & Research, Wageningen 6708 PB, Netherlands
| | - Mathew R Heal
- School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, UK
| | - Xuejun Liu
- State Key Laboratory of Nutrient Use and Management, College of Resources and Environmental Sciences, Key Laboratory of Plant-Soil Interactions, Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing 100193, China
| | - Xueyan Liu
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Yuanhong Zhao
- College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China
| | - Maryna Strokal
- Earth Systems and Global Change Group, Wageningen University & Research, Wageningen 6708 PB, Netherlands
| | - Carolien Kroeze
- Earth Systems and Global Change Group, Wageningen University & Research, Wageningen 6708 PB, Netherlands
| | - Fusuo Zhang
- State Key Laboratory of Nutrient Use and Management, College of Resources and Environmental Sciences, Key Laboratory of Plant-Soil Interactions, Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing 100193, China
| | - Wen Xu
- State Key Laboratory of Nutrient Use and Management, College of Resources and Environmental Sciences, Key Laboratory of Plant-Soil Interactions, Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing 100193, China
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2
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Qu R, Mao S, Wang X, Ren N. Nitrogen fate in riparian zones: Insights from experiments and analysis of sediment porosity and surface water-groundwater exchange. ENVIRONMENTAL RESEARCH 2024; 262:119914. [PMID: 39233031 DOI: 10.1016/j.envres.2024.119914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 08/29/2024] [Accepted: 09/01/2024] [Indexed: 09/06/2024]
Abstract
Riparian zones play a vital role in the river ecosystem. Solutes in vertical riparian zones are transported being by alternating hydraulic gradients between river water and groundwater, due to natural or human activities. This study investigates the impacts of porous sediments and alternating rate of surface water-groundwater on nitrogen removal in the riparian zone through experiments based on the field sampled. The experimental results, combined with dimensionless numbers (Péclet and Damköhler) and Partial Least Squares-Path Modeling, analyze the nitrogen fate responding to hydrodynamics changes. The results show that increased sediment porosity contributes to the ammonium removal, particularly when the oxygen content of river water is low, with the removal rate up to 72.57%. High ammonium content and dissolved organic carbon (DOC) in rural rivers lead to a constant low-oxygen condition (4 mg/L) during surface water-groundwater alternation, and promote denitrification. This threatens groundwater with ammonium pollution and causes accumulation at the top of vertical riparian zones during upwelling, potentially causing secondary river pollution. However, increasing the alternating rate hinders the nitrate denitrification and drastically changes in the redox environment of the riparian zone, despite contributing to ammonium removal. Rapid oxygen consumption during aerobic metabolism and nitrification in groundwater-surface water exchange created favorable conditions for denitrification. Floodplains sediment porosity is unfavorable for nitrification. This study improves understanding of coupled hydrologic and solute processes in vertical riparian zones, informing strategies for optimizing nitrogen attenuation and riparian zone construction.
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Affiliation(s)
- Ruizhuo Qu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Shuoyu Mao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Xiuheng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China; School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
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Mengistu SG, Golden HE, Lane CR, Christensen JC, Wine ML, D’Amico E, Prues A, Leibowitz SG, Compton JE, Weber MH, Hill RA. Wetland Flowpaths Mediate Nitrogen and Phosphorus Concentrations across the Upper Mississippi River Basin. JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION 2023; 59:1162-1179. [PMID: 38152418 PMCID: PMC10750867 DOI: 10.1111/1752-1688.12885] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 09/21/2020] [Indexed: 12/29/2023]
Abstract
Eutrophication, harmful algal blooms, and human health impacts are critical environmental challenges resulting from excess nitrogen and phosphorus in surface waters. Yet we have limited information regarding how wetland characteristics mediate water quality across watershed scales. We developed a large, novel set of spatial variables characterizing hydrological flowpaths from wetlands to streams, that is, "wetland hydrological transport variables," to explore how wetlands statistically explain the variability in total nitrogen (TN) and total phosphorus (TP) concentrations across the Upper Mississippi River Basin (UMRB) in the United States. We found that wetland flowpath variables improved landscape-to-aquatic nutrient multilinear regression models (from R2 = 0.89 to 0.91 for TN; R2 = 0.53 to 0.84 for TP) and provided insights into potential processes governing how wetlands influence watershed-scale TN and TP concentrations. Specifically, flowpath variables describing flow-attenuating environments, for example, subsurface transport compared to overland flowpaths, were related to lower TN and TP concentrations. Frequent hydrological connections from wetlands to streams were also linked to low TP concentrations, which likely suggests a nutrient source limitation in some areas of the UMRB. Consideration of wetland flowpaths could inform management and conservation activities designed to reduce nutrient export to downstream waters.
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Affiliation(s)
- Samson G. Mengistu
- National Research Council, National Academy of Science @ US Environmental Protection Agency (USEPA), Office of Research and Development, Cincinnati, Ohio USA
| | - Heather E. Golden
- USEPA, Office of Research and Development, National Center for Measurement and Modeling, Cincinnati, Ohio, USA
| | - Charles R. Lane
- USEPA, Office of Research and Development, National Center for Measurement and Modeling, Cincinnati, Ohio, USA
| | - Jay C. Christensen
- USEPA, Office of Research and Development, National Center for Measurement and Modeling, Cincinnati, Ohio, USA
| | - Michael L. Wine
- Oak Ridge Institute for Science and Education @ US Environmental Protection Agency (USEPA), Office of Research and Development, Cincinnati, Ohio USA
| | - Ellen D’Amico
- Pegasus Technical Services, Inc., Cincinnati, Ohio, USA
| | - Amy Prues
- Pegasus Technical Services, Inc., Cincinnati, Ohio, USA
| | - Scott G. Leibowitz
- USEPA, Office of Research and Development, National Center for Public Health and Environmental Assessment, Corvallis, Oregon, USA
| | - Jana E. Compton
- USEPA, Office of Research and Development, National Center for Public Health and Environmental Assessment, Corvallis, Oregon, USA
| | - Marc H. Weber
- USEPA, Office of Research and Development, National Center for Public Health and Environmental Assessment, Corvallis, Oregon, USA
| | - Ryan A. Hill
- USEPA, Office of Research and Development, National Center for Public Health and Environmental Assessment, Corvallis, Oregon, USA
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Doyle JM, Hill RA, Leibowitz SG, Ebersole JL. Random Forest models to estimate bankfull and low flow channel widths and depths across the conterminous United States. JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION 2023; 59:1099-1114. [PMID: 37941964 PMCID: PMC10631553 DOI: 10.1111/1752-1688.13116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 02/18/2023] [Indexed: 11/10/2023]
Abstract
Channel dimensions (width and depth) at varying flows influence a host of instream ecological processes, as well as habitat and biotic features; they are a major consideration in stream habitat restoration and instream flow assessments. Models of widths and depths are often used to assess climate change vulnerability, develop endangered species recovery plans, and model water quality. However, development and application of such models require specific skillsets and resources. To facilitate acquisition of such estimates, we created a dataset of modeled channel dimensions for perennial stream segments across the conterminous U.S. We used random forest models to predict wetted width, thalweg depth, bankfull width, and bankfull depth from several thousand field measurements of the National Rivers and Streams Assessment. Observed channel widths varied from <5 m to >2000 m and depths varied from <2 m to >125 m. Metrics of watershed area, runoff, slope, land use, and more were used as model predictors. The models had high pseudo R-squared values (0.70 to 0.91) and median absolute errors within ±6% to ±21% of the interquartile range of measured values across ten stream orders. Predicted channel dimensions can be joined to 1.1 million stream segments of the 1:100K resolution National Hydrography Dataset Plus (version 2.1). These predictions, combined with a rapidly growing body of nationally available data, will further enhance our ability to study and protect aquatic resources.
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Affiliation(s)
- Jessie M Doyle
- Oak Ridge Institute for Science and Education c/o Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Doyle), U.S. Environmental Protection Agency, Corvallis, Oregon USA; Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Hill, Leibowitz, Ebersole), U.S. Environmental Protection Agency, Corvallis, Oregon, USA
| | - Ryan A Hill
- Oak Ridge Institute for Science and Education c/o Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Doyle), U.S. Environmental Protection Agency, Corvallis, Oregon USA; Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Hill, Leibowitz, Ebersole), U.S. Environmental Protection Agency, Corvallis, Oregon, USA
| | - Scott G Leibowitz
- Oak Ridge Institute for Science and Education c/o Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Doyle), U.S. Environmental Protection Agency, Corvallis, Oregon USA; Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Hill, Leibowitz, Ebersole), U.S. Environmental Protection Agency, Corvallis, Oregon, USA
| | - Joseph L Ebersole
- Oak Ridge Institute for Science and Education c/o Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Doyle), U.S. Environmental Protection Agency, Corvallis, Oregon USA; Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division (Hill, Leibowitz, Ebersole), U.S. Environmental Protection Agency, Corvallis, Oregon, USA
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5
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Zhao G, Sun T, Wang D, Chen S, Ding Y, Li Y, Shi G, Sun H, Wu S, Li Y, Wu C, Li Y, Yu Z, Chen Z. Treated wastewater and weak removal mechanisms enhance nitrate pollution in metropolitan rivers. ENVIRONMENTAL RESEARCH 2023; 231:116182. [PMID: 37201708 DOI: 10.1016/j.envres.2023.116182] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/07/2023] [Accepted: 05/15/2023] [Indexed: 05/20/2023]
Abstract
The focus of urban water environment renovation has shifted to high nitrate (NO3-) load. Nitrate input and nitrogen conversion are responsible for the continuous increase in nitrate levels in urban rivers. This study utilized nitrate stable isotopes (δ15N-NO3- and δ18O-NO3-) to investigate NO3- sources and transformation processes in Suzhou Creek, located in Shanghai. The results demonstrated that NO3- was the most common form of dissolved inorganic nitrogen (DIN), accounting for 66 ± 14% of total DIN with a mean value of 1.86 ± 0.85 mg L-1. The δ15N-NO3- and δ18O-NO3- values ranged from 5.72 to 12.42‰ (mean value: 8.38 ± 1.54‰) and -5.01 to 10.39‰ (mean value: 0.58 ± 1.76‰), respectively. Based on isotopic evidence, the river received a significant amount of nitrate through direct exogenous input and sewage ammonium nitrification, while nitrate removal (denitrification) was insignificant, resulting in nitrate accumulation. Analysis using the MixSIAR model revealed that treated wastewater (68.3 ± 9.7%), soil nitrogen (15.7 ± 4.8%) and nitrogen fertilizer (15.5 ± 4.9%) were the main sources of NO3- in rivers. Despite the fact that Shanghai's urban domestic sewage recovery rate has reached 92%, reducing nitrate concentrations in treated wastewater is crucial for addressing nitrogen pollution in urban rivers. Additional efforts are needed to upgrade urban sewage treatment during low flow periods and/or in the main stream, and to control non-point sources of nitrate, such as soil nitrogen and nitrogen fertilizer, during high flow periods and/or tributaries. This research provides insights into NO3- sources and transformations, and serves as a scientific basis for controlling NO3- in urban rivers.
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Affiliation(s)
- Guanghui Zhao
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Taihu Sun
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Dongqi Wang
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai, 200241, China.
| | - Shu Chen
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China; College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China; Research Institute of Carbon Neutrality, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yan Ding
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Yilan Li
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Guitao Shi
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Hechen Sun
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Shengnan Wu
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Yizhe Li
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Chenyang Wu
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Yufang Li
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
| | - Zhongjie Yu
- Department of Natural Resources and Environmental Sciences, University of Illinois Urbana-Champaign, Urbana, 61801, IL, USA
| | - Zhenlou Chen
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China.
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6
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Lassiter MG, Lin J, Compton JE, Phelan J, Sabo RD, Stoddard JL, McDow SR, Greaver TL. Shifts in the composition of nitrogen deposition in the conterminous United States are discernable in stream chemistry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 881:163409. [PMID: 37044336 PMCID: PMC10332341 DOI: 10.1016/j.scitotenv.2023.163409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/13/2023] [Accepted: 04/06/2023] [Indexed: 04/14/2023]
Abstract
Across the conterminous United States (U.S.), the composition of atmospheric nitrogen (N) deposition is changing spatially and temporally. Previously, deposition was dominated by oxidized N, but now reduced N (ammonia [NH3] + ammonium [NH4+]) is equivalent to oxidized N when deposition is averaged across the entire nation and, in some areas, reduced N dominates deposition. To evaluate if there are effects of this change on stream chemistry at the national scale, estimates of N deposition form (oxidized or reduced) from the National Atmospheric Deposition Program Total Deposition data were coupled with stream measurements from the U.S. Environmental Protection Agency (EPA) National Rivers and Streams Assessments (three stream surveys between 2000 and 2014). A recent fine-scaled N input inventory was used to identify watersheds (<1000 km2) where atmospheric deposition is the largest N source (n = 1906). Within these more atmospherically-influenced watersheds there was a clear temporal shift from a greater proportion of sites dominated by oxidized N deposition to a greater proportion of sites dominated by reduced forms of N deposition. We found a significant positive correlation between oxidized N deposition and stream NO3- concentrations, whereas the correlation between reduced N deposition and stream NO3- concentrations were significant but weaker. Sites dominated by atmospheric inputs of reduced N forms had higher stream total organic N and total N despite lower total N deposition on average. This higher stream concentration of total N is mainly driven by the higher concentration of total organic N, suggesting an interaction between elevated reduced N in deposition and living components of the ecosystem or soil organic matter dynamics. Regardless of the proportion of reduced to oxidized N forms in deposition, stream NH4+ concentrations were generally low, suggesting that N deposited in a reduced form is rapidly immobilized, nitrified and/or assimilated by watershed processes.
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Affiliation(s)
- Meredith G Lassiter
- United States Environmental Protection Agency (U.S. EPA), Office of Research and Development, Center for Public Health and Environmental Assessment, Health and Environmental Effects Assessment Division, 109 T.W. Alexander Dr. Research Triangle Park, NC 27709, United States.
| | - Jiajia Lin
- Oak Ridge Institute for Science and Education, Postdoctoral Participant, Corvallis, OR 97333, United States; U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, 200 SW 35th St., Corvallis, OR 97333, United States.
| | - Jana E Compton
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, 200 SW 35th St., Corvallis, OR 97333, United States.
| | - Jennifer Phelan
- RTI International, P.O. Box 12194, 3040 Cornwallis Rd., RTP, NC 27709, United States.
| | - Robert D Sabo
- US EPA Headquarters, Office of Research and Development, Center for Public Health and Environmental Assessment, Health and Environmental Effects Assessment Division, 1200 Penn Ave NW, Mailcode 8623-P, Washington, DC 20460, United States.
| | - John L Stoddard
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, 200 SW 35th St., Corvallis, OR 97333, United States.
| | - Stephen R McDow
- United States Environmental Protection Agency (U.S. EPA), Office of Research and Development, Center for Public Health and Environmental Assessment, Health and Environmental Effects Assessment Division, 109 T.W. Alexander Dr. Research Triangle Park, NC 27709, United States.
| | - Tara L Greaver
- United States Environmental Protection Agency (U.S. EPA), Office of Research and Development, Center for Public Health and Environmental Assessment, Health and Environmental Effects Assessment Division, 109 T.W. Alexander Dr. Research Triangle Park, NC 27709, United States.
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7
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Bunyaga A, Corner-Thomas R, Draganova I, Kenyon P, Burkitt L. The Behaviour of Sheep around a Natural Waterway and Impact on Water Quality during Winter in New Zealand. Animals (Basel) 2023; 13:ani13091461. [PMID: 37174500 PMCID: PMC10177330 DOI: 10.3390/ani13091461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/19/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
Access of livestock, such as cattle, to waterways has been shown to be a cause of poor water quality due to pugging damage and excretion entering the water. In New Zealand, regulations require that cattle, deer, and pigs are excluded from accessing waterways, but there are no such requirements for sheep. The current study utilised 24 h video cameras, global positioning system units, and triaxial accelerometers to observe the interaction of Romney ewes (n = 40) with a natural waterway. Ewes were either restricted (week 1) or given access to a reticulated water trough (week 2). Proximity data showed that ewes spent more time within 3 m of the waterway when the trough was unrestricted than when restricted (14.1 ± 5.7 and 10.8 ± 5.1 min/ewe/day, respectively; p < 0.05). Ewes travelled shorter distances on the steeper areas of paddock than flatter areas. Similarly, ewes showed a spatial preference for the flat and low sloped areas of the paddock. Concentrations of suspended sediment and total phosphorus were higher during access to a reticulated water trough which coincided with the week with more rainy days. Phosphorus and E. coli concentrations in the stream water samples were the above recommended Australian and New Zealand Environment and Conservation Council water quality guidelines, especially after rainy days, but did not appear to be directly related to sheep activity. Overall, the results suggest that during winter, ewes interacted very little with the waterway and were thus unlikely to influence the levels of nutrient and pathogens in the waterway.
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Affiliation(s)
- Aloyce Bunyaga
- College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3020, Tanzania
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Rene Corner-Thomas
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Ina Draganova
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Paul Kenyon
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Lucy Burkitt
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
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Leibowitz SG, Hill RA, Creed IF, Compton JE, Golden HE, Weber MH, Rains MC, Jones CE, Lee EH, Christensen JR, Bellmore RA, Lane CR. National hydrologic connectivity classification links wetlands with stream water quality. NATURE WATER 2023; 1:370-380. [PMID: 37389401 PMCID: PMC10302404 DOI: 10.1038/s44221-023-00057-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 02/27/2023] [Indexed: 07/01/2023]
Abstract
Wetland hydrologic connections to downstream waters influence stream water quality. However, no systematic approach for characterizing this connectivity exists. Here using physical principles, we categorized conterminous US freshwater wetlands into four hydrologic connectivity classes based on stream contact and flowpath depth to the nearest stream: riparian, non-riparian shallow, non-riparian mid-depth and non-riparian deep. These classes were heterogeneously distributed over the conterminous United States; for example, riparian dominated the south-eastern and Gulf coasts, while non-riparian deep dominated the Upper Midwest and High Plains. Analysis of a national stream dataset indicated acidification and organic matter brownification increased with connectivity. Eutrophication and sedimentation decreased with wetland area but did not respond to connectivity. This classification advances our mechanistic understanding of wetland influences on water quality nationally and could be applied globally.
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Affiliation(s)
- Scott G. Leibowitz
- US Environmental Protection Agency (EPA), Center for Public Health and Environmental Assessment (CPHEA), Pacific Ecological Systems Division (PESD), Corvallis, OR, USA
| | - Ryan A. Hill
- US Environmental Protection Agency (EPA), Center for Public Health and Environmental Assessment (CPHEA), Pacific Ecological Systems Division (PESD), Corvallis, OR, USA
| | - Irena F. Creed
- Department of Physical and Environmental Science, University of Toronto, Toronto, Ontario, Canada
| | - Jana E. Compton
- US Environmental Protection Agency (EPA), Center for Public Health and Environmental Assessment (CPHEA), Pacific Ecological Systems Division (PESD), Corvallis, OR, USA
| | - Heather E. Golden
- US EPA, Center for Environmental Measurement and Modeling (CEMM), Watershed and Ecosystem Characterization Division, Cincinnati, OH, USA
| | - Marc H. Weber
- US Environmental Protection Agency (EPA), Center for Public Health and Environmental Assessment (CPHEA), Pacific Ecological Systems Division (PESD), Corvallis, OR, USA
| | - Mark C. Rains
- School of Geosciences, University of South Florida, Tampa, FL, USA
| | - Chas E. Jones
- ORISE Post-doctoral Participant, c/o US EPA, CPHEA, PESD, Corvallis, OR, USA
- Present address: Affiliated Tribes of Northwest Indians, Portland, OR, USA
| | - E. Henry Lee
- US Environmental Protection Agency (EPA), Center for Public Health and Environmental Assessment (CPHEA), Pacific Ecological Systems Division (PESD), Corvallis, OR, USA
| | - Jay R. Christensen
- US EPA, Center for Environmental Measurement and Modeling (CEMM), Watershed and Ecosystem Characterization Division, Cincinnati, OH, USA
| | - Rebecca A. Bellmore
- National Research Council, c/o US EPA, CPHEA, PESD, Corvallis, OR, USA
- Present address: Southeast Alaska Watershed Coalition, Juneau, AK, USA
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9
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Brooks JR, Compton JE, Lin J, Herlihy A, Nahlik AM, Rugh W, Weber M. δ 15N of Chironomidae: An index of nitrogen sources and processing within watersheds for national aquatic monitoring programs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:151867. [PMID: 34826484 PMCID: PMC8865614 DOI: 10.1016/j.scitotenv.2021.151867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 06/13/2023]
Abstract
Nitrogen (N) removal along flowpaths to aquatic ecosystems is an important regulating ecosystem service that can help reduce N pollution in the nation's waterways, but can be challenging to measure at large spatial scales. Measurements that integrate N processing within watersheds would be particularly useful for assessing the magnitude of this vital service. Because most N removal processes cause isotopic fractionation, δ15N from basal food-chain organisms in aquatic ecosystems can provide information on both N sources and the degree of watershed N processing. As part of EPA's National Aquatic Resource Surveys (NARS), we measured δ15N of Chironomidae collected from over 2000 lakes, rivers and streams across the continental USA. Using information on N inputs to watersheds and summer total N concentrations ([TN]) in the water column, we assessed where elevated chironomid δ15N would indicate N removal rather than possible enriched sources of N. Chironomid δ15N values ranged from -4 to +20‰, and were higher in rivers and streams than in lakes, indicating that N in rivers and streams underwent more processing and cycling that preferentially removes 14N than N in lakes. Chironomid δ15N increased with watershed size, N inputs, and water chemical components, and decreased as precipitation increased. In rivers and streams with high watershed N inputs, we found lower [TN] in streams with higher chironomid δ15N values, suggesting high rates of gaseous N loss such as denitrification. At low watershed N inputs, the pattern reversed; streams with elevated chironomid δ15N had higher [TN] than streams with lower chironomid δ15N, possibly indicating unknown sources elevated in δ15N such as legacy N, or waste from animals or humans. Chironomid δ15N values can be a valuable tool to assess integrated watershed-level N sources, input rates, and processing for water quality monitoring and assessment at large scales.
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Affiliation(s)
- J Renée Brooks
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America.
| | - Jana E Compton
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America
| | - Jiajia Lin
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America; Oak Ridge Institute for Science and Education, United States of America
| | - Alan Herlihy
- Oregon State University, Department of Fisheries and Wildlife, United States of America
| | - Amanda M Nahlik
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America
| | - William Rugh
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America
| | - Marc Weber
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, United States of America
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10
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Abstract
AbstractWatershed resilience is the ability of a watershed to maintain its characteristic system state while concurrently resisting, adapting to, and reorganizing after hydrological (for example, drought, flooding) or biogeochemical (for example, excessive nutrient) disturbances. Vulnerable waters include non-floodplain wetlands and headwater streams, abundant watershed components representing the most distal extent of the freshwater aquatic network. Vulnerable waters are hydrologically dynamic and biogeochemically reactive aquatic systems, storing, processing, and releasing water and entrained (that is, dissolved and particulate) materials along expanding and contracting aquatic networks. The hydrological and biogeochemical functions emerging from these processes affect the magnitude, frequency, timing, duration, storage, and rate of change of material and energy fluxes among watershed components and to downstream waters, thereby maintaining watershed states and imparting watershed resilience. We present here a conceptual framework for understanding how vulnerable waters confer watershed resilience. We demonstrate how individual and cumulative vulnerable-water modifications (for example, reduced extent, altered connectivity) affect watershed-scale hydrological and biogeochemical disturbance response and recovery, which decreases watershed resilience and can trigger transitions across thresholds to alternative watershed states (for example, states conducive to increased flood frequency or nutrient concentrations). We subsequently describe how resilient watersheds require spatial heterogeneity and temporal variability in hydrological and biogeochemical interactions between terrestrial systems and down-gradient waters, which necessitates attention to the conservation and restoration of vulnerable waters and their downstream connectivity gradients. To conclude, we provide actionable principles for resilient watersheds and articulate research needs to further watershed resilience science and vulnerable-water management.
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11
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Zhang J, Huang Z, Gao L, Gray S, Xie Z. Study of MOF incorporated dual layer membrane with enhanced removal of ammonia and per-/poly-fluoroalkyl substances (PFAS) in landfill leachate treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:151207. [PMID: 34728199 DOI: 10.1016/j.scitotenv.2021.151207] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 05/26/2023]
Abstract
Landfill leachate is a highly polluted and complex wastewater as it contains large amounts of organic matters, ammonia‑nitrogen, heavy metals, and per-/poly-fluoroalkyl substances (PFAS), which makes its treatment very challenging. In this paper, hydrophilic/hydrophobic dual layer membranes combining advantages of pervaporation and membrane distillation was employed to treat leachate in a direct contact membrane distillation (DCMD) configuration. An aluminum fumarate (AlFu) metal organic framework (MOF) incorporated poly(vinyl alcohol) (PVA) hydrophilic layer was coated on hydrophobic PTFE membrane to overcome the low separation efficiency of PFAS and ammonia and wetting issues encountered by the conventional hydrophobic PTFE membrane used for DCMD. The rejections of dual layer membranes with different MOF loading to PFAS, ammonia, TOC and TDS were assessed based on the amount of AlFu MOF incorporated into the PVA layer. Based on the conducted adsorption tests, it was found that AlFu MOF increases the rejection of PVA layer to PFAS and ammonia. The coating of the hydrophilic layer could enhance the wetting resistance with/without MOF addition. In comparison with the pristine PTFE membrane using synthetic feed containing 3 wt% NaCl, 1 wt% addition of AlFu MOF into the PVA layer showed slightly increased flux. All the tested membranes showed more than 99% rejection to TOC. The rejection to ammonia was increased as more MOF was incorporated into the PVA layer. The maximum rejection of ammonia was 99.8% when the PVA layer containing 10% MOF. All the membranes showed more than 99% rejection to PFOS and PFHxS. However, PTFE membrane did not show any rejection to PFOA. As more MOF was added into the hydrophilic layer, the rejection to PFOA increased, but plateaued at 65.6% with 5% MOF incorporation into the hydrophilic layer.
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Affiliation(s)
- Jianhua Zhang
- Institute for Sustainable Industries and Liveable Cities, Victoria University, PO Box 14428, Melbourne, Vic. 8001, Australia.
| | - Zhen Huang
- CSIRO Manufacturing, Private Bag 10, Clayton South, Vic. 3169, Australia
| | - Li Gao
- South East Water Corporation, PO Box 2268, Seaford, Victoria 3198, Australia
| | - Stephen Gray
- Institute for Sustainable Industries and Liveable Cities, Victoria University, PO Box 14428, Melbourne, Vic. 8001, Australia
| | - Zongli Xie
- CSIRO Manufacturing, Private Bag 10, Clayton South, Vic. 3169, Australia
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12
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Pennino MJ, Leibowitz SG, Compton JE, Beyene MT, LeDuc SD. Wildfires can increase regulated nitrate, arsenic, and disinfection byproduct violations and concentrations in public drinking water supplies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:149890. [PMID: 34520927 PMCID: PMC10084414 DOI: 10.1016/j.scitotenv.2021.149890] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 05/21/2023]
Abstract
Wildfires are a concern for water quality in the United States, particularly in the wildland-urban interface of populous areas. Wildfires combust vegetation and surface soil organic matter, reduce plant nutrient uptake, and can alter the composition of runoff and receiving waters. At the wildland-urban interface, fires can also introduce contaminants from the combustion of man-made structures. We examine post-wildfire effects on drinking water quality by evaluating concentrations and maximum contaminant level (MCL) violations of selected contaminants regulated in the U.S. at public drinking water systems (PWSs) located downstream from wildfire events. Among contaminants regulated under the U.S. Safe Drinking Water Act, nitrate, arsenic, disinfection byproducts, and volatile organic compounds (VOCs) were analyzed in watersheds that experienced major wildfires. Surface water sourced drinking water (SWDW) nitrate violations increased by an average of 0.56 violations per PWS and concentrations increased by 0.044 mg-N/L post-wildfire. Groundwater sourced drinking water (GWDW) nitrate violations increased by 0.069 violations per PWS and concentrations increased by 0.12 mg-N/L post-wildfire. SWDW total trihalomethane (TTHM) violations increased by 0.58 violations per PWS and concentrations increased by 10.4 μg/L. SWDW total haloacetic acid (HAA5) violations increased by 0.82 violations per PWS and concentrations increased by 8.5 μg/L. Arsenic violations increased by 1.08 violations per PWS and concentrations increased by 0.92 μg/L. There was no significant effect of wildfires on average VOC violations. Nitrate violations increased in 75% of SWDW sites and 34% of GWDW sites post-wildfire, while about 71% and 50% of SWDW sites showed an increase in TTHM and HAA5 violations. Violations also increased for 35% of arsenic and 44% of VOC sites post-wildfire. These findings support the need for increased awareness about the impact of wildfires on drinking water treatment to help PWS operators adapt to the consequences of wildfires on source water quality, particularly in wildfire-prone regions.
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Affiliation(s)
- Michael J Pennino
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Health & Environmental Effects Assessment Division, Washington, DC, USA.
| | - Scott G Leibowitz
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Jana E Compton
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Mussie T Beyene
- Oak Ridge Institute for Science and Education (ORISE), U.S. Environmental Protection Agency, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Stephen D LeDuc
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Health & Environmental Effects Assessment Division, Research Triangle Park, NC, USA
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13
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Lin J, Compton JE, Hill RA, Herlihy A, Sabo RD, Brooks JR, Weber M, Pickard B, Paulsen S, Stoddard JL. Context is Everything: Interacting Inputs and Landscape Characteristics Control Stream Nitrogen. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:7890-7899. [PMID: 34060819 PMCID: PMC8673309 DOI: 10.1021/acs.est.0c07102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
To understand the environmental and anthropogenic drivers of stream nitrogen (N) concentrations across the conterminous US, we combined summer low-flow data from 4997 streams with watershed information across three survey periods (2000-2014) of the US EPA's National Rivers and Streams Assessment. Watershed N inputs explained 51% of the variation in log-transformed stream total N (TN) concentrations. Both N source and input rates influenced stream NO3/TN ratios and N concentrations. Streams dominated by oxidized N forms (NO3/TN ratio > 0.50) were more strongly responsive to the N input rate compared to streams dominated by other N forms. NO3 proportional contribution increased with N inputs, supporting N saturation-enhanced NO3 export to aquatic ecosystems. By combining information about N inputs with climatic and landscape factors, random forest models of stream N concentrations explained 70, 58, and 60% of the spatial variation in stream concentrations of TN, dissolved inorganic N, and total organic N, respectively. The strength and direction of relationships between watershed drivers and stream N concentrations and forms varied with N input intensity. Model results for high N input watersheds not only indicated potential contributions from contaminated groundwater to high stream N concentrations but also the mitigating role of wetlands.
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Affiliation(s)
- Jiajia Lin
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
- Oak Ridge Institute for Science and Education, Corvallis, OR 97333
| | - Jana E. Compton
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
| | - Ryan A. Hill
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
| | - Alan Herlihy
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
- Oregon State University, Department of Fisheries and Wildlife, Corvallis, OR 97333
| | - Robert D. Sabo
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, HEEAD, Washington, DC 20004
| | - J. Renée Brooks
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
| | - Marc Weber
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
| | | | - Steve Paulsen
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
| | - John L. Stoddard
- US EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR 97333
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14
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Zhao S, Zhang B, Sun X, Yang L. Hot spots and hot moments of nitrogen removal from hyporheic and riparian zones: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 762:144168. [PMID: 33360457 DOI: 10.1016/j.scitotenv.2020.144168] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/01/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
The Earth is experiencing excessive nitrogen (N) input to its various ecosystems due to human activities. How to effectively and efficiently remove N from ecosystems has been, is and will be at the center of attention in N research. Hyporheic and riparian zones are widely acknowledged for their buffering capacity to reduce contaminants (especially N) transport downstream. However, these zones are usually misunderstood that they can remove N at all spots and at any moments. Here pathways of N removal from hyporheic and riparian zones are reviewed and summarized with an emphasize on their hot spots and hot moments. N is biogeochemically removed by denitrification, anammox, nitrifier denitrification, denitrifying anaerobic methane oxidation, Feammox and Sulfammox. Hot moments of N removal are mainly triggered by precipitation, fire and snowmelt. Finally, some research needs are outlined and discussed, such as developing approaches for multiscale sampling and monitoring, quantifying the effects of hot spots and hot moments at hyporheic and riparian zones and evaluating the impacts of human activities on hot spots and hot moments, to inspire more research on hot spots and hot moments of N removal. By this review, we hope to bring awareness of the heterogeneity of hyporheic and riparian zones to catchment managers and policy makers when tackling N pollution problems.
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Affiliation(s)
- Shan Zhao
- College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China; College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
| | - Baoju Zhang
- College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China
| | - Xiaohui Sun
- College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China
| | - Leimin Yang
- College of Ocean Science and Engineering, Shanghai Maritime University, 1550 Haigang Ave, Shanghai 201306, China
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15
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Stachelek J, Weng W, Carey CC, Kemanian AR, Cobourn KM, Wagner T, Weathers KC, Soranno PA. Granular measures of agricultural land use influence lake nitrogen and phosphorus differently at macroscales. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02187. [PMID: 32485044 DOI: 10.1002/eap.2187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 04/02/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
Agricultural land use is typically associated with high stream nutrient concentrations and increased nutrient loading to lakes. For lakes, evidence for these associations mostly comes from studies on individual lakes or watersheds that relate concentrations of nitrogen (N) or phosphorus (P) to aggregate measures of agricultural land use, such as the proportion of land used for agriculture in a lake's watershed. However, at macroscales (i.e., in hundreds to thousands of lakes across large spatial extents), there is high variability around such relationships and it is unclear whether considering more granular (or detailed) agricultural data, such as fertilizer application, planting of specific crops, or the extent of near-stream cropping, would improve prediction and inform understanding of lake nutrient drivers. Furthermore, it is unclear whether lake N and P would have different relationships to such measures and whether these relationships would vary by region, since regional variation has been observed in prior studies using aggregate measures of agriculture. To address these knowledge gaps, we examined relationships between granular measures of agricultural activity and lake total phosphorus (TP) and total nitrogen (TN) concentrations in 928 lakes and their watersheds in the Northeastern and Midwest U.S. using a Bayesian hierarchical modeling approach. We found that both lake TN and TP concentrations were related to these measures of agriculture, especially near-stream agriculture. The relationships between measures of agriculture and lake TN concentrations were more regionally variable than those for TP. Conversely, TP concentrations were more strongly related to lake-specific measures like depth and watershed hydrology relative to TN. Our finding that lake TN and TP concentrations have different relationships with granular measures of agricultural activity has implications for the design of effective and efficient policy approaches to maintain and improve water quality.
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Affiliation(s)
- Joseph Stachelek
- Department of Fisheries and Wildlife, Michigan State University, 480 Wilson Road, East Lansing, Michigan, 48824, USA
| | - W Weng
- School of Business, State University of New York College at Geneseo, 1 College Circle, Geneseo, New York, 14454, USA
| | - C C Carey
- Department of Biological Sciences, Virginia Tech, 926 W Campus Drive, Blacksburg, Virginia, 24061, USA
| | - A R Kemanian
- Department of Plant Science, The Pennsylvania State University, 247 Agricultural Sciences and Industries Bldg., University Park, Pennsylvania, 16802, USA
| | - K M Cobourn
- Department of Forest Resources and Environmental Conservation, Virginia Tech, 310 W Campus Drive, Blacksburg, Virginia, 24061, USA
| | - T Wagner
- U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - K C Weathers
- Cary Institute of Ecosystem Studies, 2801 Sharon Turnpike, Millbrook, New York, 12545, USA
| | - P A Soranno
- Department of Fisheries and Wildlife, Michigan State University, 480 Wilson Road, East Lansing, Michigan, 48824, USA
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16
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Gao L, Li JD, Yang G, Zhang J, Xie Z. De-ammonification using direct contact membrane distillation – An experimental and simulation study. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117158] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Metson GS, Lin J, Harrison JA, Compton JE. Where Have All the Nutrients Gone? Long-Term Decoupling of Inputs and Outputs in the Willamette River Watershed, Oregon, United States. JOURNAL OF GEOPHYSICAL RESEARCH. BIOGEOSCIENCES 2020; 125:1-16. [PMID: 36158138 PMCID: PMC9504559 DOI: 10.1029/2020jg005792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/04/2020] [Indexed: 05/26/2023]
Abstract
Better documentation and understanding of long-term temporal dynamics of nitrogen (N) and phosphorus (P) in watersheds is necessary to support effective water quality management, in part because studies have identified time lags between terrestrial nutrient balances and water quality. We present annual time series data from 1969 to 2012 for terrestrial N and P sources and monthly data from 1972 to 2013 for river N and P for the Willamette River Basin, Oregon, United States. Inputs to the watershed increased by factors of 3 for N and 1.2 for P. Synthetic fertilizer inputs increased in total and relative importance over time, while sewage inputs decreased. For N, increased fertilizer application was not matched by a proportionate increase in crop harvest; N use efficiency decreased from 69% to 38%. P use efficiency increased from 52% to 67%. As nutrient inputs to terrestrial systems increased, river concentrations and loads of total N, total P, and dissolved inorganic P decreased, and annual nutrient loads were strongly related to discharge. The N:P ratio of both sewage and fertilizer doubled over time but there was no similar trend in riverine export; river N:P concentrations declined dramatically during storms. River nutrient export over time was related to hydrology and waste discharge, with relatively little influence of watershed balances, suggesting that accumulation within soils or groundwater over time is mediating watershed export. Simply managing yearly nutrient balances is unlikely to improve water quality; rather, many factors must be considered, including soil and groundwater storage capacity, and gaseous loss pathways.
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Affiliation(s)
- Genevieve S Metson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
- National Research Council, National Academies of Science, Washington, DC, USA
- Pacific Ecological Systems Division, US Environmental Protection Agency, Corvallis, OR, USA
- School of the Environment, Washington State University, Vancouver, WA, USA
| | - Jiajia Lin
- National Research Council, National Academies of Science, Washington, DC, USA
- Pacific Ecological Systems Division, US Environmental Protection Agency, Corvallis, OR, USA
- Oak Ridge Institute for Science and Education, Corvallis, OR, USA
| | - John A Harrison
- School of the Environment, Washington State University, Vancouver, WA, USA
| | - Jana E Compton
- Pacific Ecological Systems Division, US Environmental Protection Agency, Corvallis, OR, USA
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18
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Manning DWP, Rosemond AD, Benstead JP, Bumpers PM, Kominoski JS. Transport of N and P in U.S. streams and rivers differs with land use and between dissolved and particulate forms. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02130. [PMID: 32227394 PMCID: PMC7507146 DOI: 10.1002/eap.2130] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 12/06/2019] [Accepted: 02/24/2020] [Indexed: 06/02/2023]
Abstract
We used a recently published, open-access data set of U.S. streamwater nitrogen (N) and phosphorus (P) concentrations to test whether watershed land use differentially influences N and P concentrations, including the relative availability of dissolved and particulate nutrient fractions. We tested the hypothesis that N and P concentrations and molar ratios in streams and rivers of the United States reflect differing nutrient inputs from three dominant land-use types (agricultural, urban and forested). We also tested for differences between dissolved inorganic nutrients and suspended particulate nutrient fractions to infer sources and potential processing mechanisms across spatial and temporal scales. Observed total N and P concentrations often exceeded reported thresholds for structural changes to benthic algae (58, 57% of reported values, respectively), macroinvertebrates (39% for TN and TP), and fish (41, 37%, respectively). The majority of dissolved N and P concentrations exceeded threshold concentrations known to stimulate benthic algal growth (85, 87%, respectively), and organic matter breakdown rates (94, 58%, respectively). Concentrations of both N and P, and total and dissolved N:P ratios, were higher in streams and rivers with more agricultural and urban than forested land cover. The pattern of elevated nutrient concentrations with agricultural and urban land use was weaker for particulate fractions. The % N contained in particles decreased slightly with higher agriculture and urbanization, whereas % P in particles was unrelated to land use. Particulate N:P was relatively constant (interquartile range = 2-7) and independent of variation in DIN:DIP (interquartile range = 22-152). Dissolved, but not particulate, N:P ratios were temporally variable. Constant particulate N:P across steep DIN:DIP gradients in both space and time suggests that the stoichiometry of particulates across U.S. watersheds is most likely controlled either by external or by physicochemical instream factors, rather than by biological processing within streams. Our findings suggest that most U.S. streams and rivers have concentrations of N and P exceeding those considered protective of ecological integrity, retain dissolved N less efficiently than P, which is retained proportionally more in particles, and thus transport and export high N:P streamwater to downstream ecosystems on a continental scale.
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Affiliation(s)
- David W. P. Manning
- Odum School of EcologyUniversity of GeorgiaAthensGeorgia30602USA
- Department of BiologyUniversity of Nebraska at OmahaOmahaNebraska68182USA
| | - Amy D. Rosemond
- Odum School of EcologyUniversity of GeorgiaAthensGeorgia30602USA
| | | | | | - John S. Kominoski
- Department of Biological SciencesFlorida International UniversityMiamiFlorida33199USA
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19
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Xie R, Rao P, Pang Y, Shi C, Li J, Shen D. Salt intrusion alters nitrogen cycling in tidal reaches as determined in field and laboratory investigations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 729:138803. [PMID: 32361438 DOI: 10.1016/j.scitotenv.2020.138803] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/06/2020] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Salinization is a growing problem throughout the world and poses a threat especially to freshwater ecosystems. However, much remains to be learned about the mechanisms by which salinity impacts microbially mediated biogeochemical processes. Elevated nitrogen (N) concentrations in estuarine ecosystems have led to their eutrophication, but the relationship between N transformation and the functional genes involved in the response to saltwater intrusion is poorly understood. Here, using the Minjiang River, a tidal river in southeastern China as an easily accessible natural laboratory, we conducted a 2-year field survey to investigate N speciation during ebb and flood tides. Then, in a laboratory experiment we simulated the varying degrees of salt intrusion that occur in natural tidal reaches. The microcosm study allowed quantitative assessments of N transformation and functional gene responses. The field surveys showed that concentrations of NH4+ rose during flood tides, while the concentrations of NO3- and total N fluctuated. In the microcosms, NO3- concentrations decreased in response to salt pulses, due to simultaneous declines in the abundance of genes responsible for nitrification and increases in the abundance of those involved in dissimilatory nitrate reduction to ammonium (DNRA). The elevated salinity led to increased yields of NH4+, a response that correlated positively with the abundance of nrfA genes, involved in DNRA. Furthermore, an increase in salinity promoted N2O accumulation during the denitrification process. Altogether, our study suggests that saltwater intrusion leads to a decrease in nitrification while favoring N transformation via denitrification and DNRA and that N2O accumulation in the water is dependent on the strength of the salt pulse.
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Affiliation(s)
- Rongrong Xie
- College of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, China; Key Laboratory of Pollution Control and Resource Recycling of Fujian Province, Fujian Normal University, Fuzhou 350007, China; Section of Physical Oceanography and Instrumentation, Leibniz Institute for Baltic Sea Research, Warnemuende, D-18119 Rostock, Germany
| | - Peiyuan Rao
- College of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, China
| | - Yong Pang
- College of Environment, Hohai University, Nanjing 210098, China
| | - Chengchun Shi
- Fuzhou Research Academy of Environmental Sciences, Fuzhou 350013, China
| | - Jiabing Li
- College of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, China; Key Laboratory of Pollution Control and Resource Recycling of Fujian Province, Fujian Normal University, Fuzhou 350007, China.
| | - Dandan Shen
- Section of Biological Oceanography, Leibniz Institute for Baltic Sea Research, Warnemuende, D-18119 Rostock, Germany; Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden.
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20
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Wu D, Sun Y, Wang L, Zhang Z, Gui J, Ding A. Modification of NaY zeolite by lanthanum and hexadecyl trimethyl ammonium bromide and its removal performance for nitrate. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:987-996. [PMID: 31833589 DOI: 10.1002/wer.1285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/25/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Nitrate in the effluent of wastewater treatment plants (WWTPs) is the main nitrogen resource in natural water. The excessive nitrogen in natural water causes ecological issues such as aqueous eutrophication. A novel modified NaY zeolite (SMZ-La) with hexadecyl trimethyl ammonium bromide (HDTMA) and lanthanum (La) as modifying agents for NO 3 - -N adsorption was investigated in this study. Results showed that SMZ-La had a higher adsorption capacity (3.82 mg NO 3 - -N/g) than zeolite only modified with HDTMA or La (2.75 and 2.23 mg NO 3 - -N/g, respectively). Moreover, the adsorption process was endothermic with a maximum theoretic adsorption of 14.49 mg NO 3 - -N/g. X-ray photoelectron spectroscopy (XPS) analysis indicated that adsorption rate principally depended on chemisorption between SMZ and NO 3 - -N. Thermogravimetric analysis showed that HDTMA was loaded on the surface of NaY zeolite with double layer. Scanning electron microscope and X-ray spectroscopy analysis illustrated that La was primarily loaded in the pore of NaY zeolite, and the loading of HDTMA and La did not affect the original crystal structure of NaY zeolite. The novel adsorbent provided a promising perspective for nitrogen control in WWTPs and natural water. PRACTITIONER POINTS: A novel modified zeolite (SMZ-La) was prepared successfully with HDTMA and La. SMZ-La had an excellent adsorption capacity compared to SMZ and NaY-La. There were both physical and chemical adsorptions in the adsorption process of SMZ-La on NO 3 - -N.
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Affiliation(s)
- Donglei Wu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Yue Sun
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Linlin Wang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Zhiming Zhang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Jiaxi Gui
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Aqiang Ding
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
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Pennino MJ, Leibowitz SG, Compton JE, Hill RA, Sabo RD. Patterns and predictions of drinking water nitrate violations across the conterminous United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 722:137661. [PMID: 32192969 PMCID: PMC8204728 DOI: 10.1016/j.scitotenv.2020.137661] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/28/2020] [Accepted: 02/29/2020] [Indexed: 05/12/2023]
Abstract
Excess nitrate in drinking water is a human health concern, especially for young children. Public drinking water systems in violation of the 10 mg nitrate-N/L maximum contaminant level (MCL) must be reported in EPA's Safe Drinking Water Information System (SDWIS). We used SDWIS data with random forest modeling to examine the drivers of nitrate violations across the conterminous U.S. and to predict where public water systems are at risk of exceeding the nitrate MCL. As explanatory variables, we used land cover, nitrogen inputs, soil/hydrogeology, and climate variables. While we looked at the role of nitrate treatment in separate analyses, we did not include treatment as a factor in the final models, due to incomplete information in SDWIS. For groundwater (GW) systems, a classification model correctly classified 79% of catchments in violation and a regression model explained 43% of the variation in nitrate concentrations above the MCL. The most important variables in the GW classification model were % cropland, agricultural drainage, irrigation-to-precipitation ratio, nitrogen surplus, and surplus precipitation. Regions predicted to have risk for nitrate violations in GW were the Central California Valley, parts of Washington, Idaho, the Great Plains, Piedmont of Pennsylvania and Coastal Plains of Delaware, and regions of Wisconsin, Iowa, and Minnesota. For surface water (SW) systems, a classification model correctly classified 90% of catchments and a regression model explained 52% of the variation in nitrate concentration. The variables most important for the SW classification model were largely hydroclimatic variables including surplus precipitation, irrigation-to-precipitation ratio, and % shrubland. Areas at greatest risk for SW nitrate violations were generally in the non-mountainous west and southwest. Identifying the areas with possible risk for future violations and potential drivers of nitrate violations across U.S. can inform decisions on how source water protection and other management options could best protect drinking water.
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Affiliation(s)
- Michael J Pennino
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Health & Environmental Effects Assessment Division, Washington, DC, USA.
| | - Scott G Leibowitz
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Jana E Compton
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Ryan A Hill
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, USA
| | - Robert D Sabo
- U.S. EPA, Office of Research and Development, Center for Public Health and Environmental Assessment, Health & Environmental Effects Assessment Division, Washington, DC, USA
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22
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Lee CM, Hamm SY, Cheong JY, Kim K, Yoon H, Kim M, Kim J. Contribution of nitrate-nitrogen concentration in groundwater to stream water in an agricultural head watershed. ENVIRONMENTAL RESEARCH 2020; 184:109313. [PMID: 32151840 DOI: 10.1016/j.envres.2020.109313] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/26/2020] [Accepted: 02/26/2020] [Indexed: 06/10/2023]
Abstract
This study characterized nitrate-nitrogen (NO3-N) concentrations in groundwater and stream water in an agricultural head watershed in South Korea and identified the pollution load of NO3-N as a result of the groundwater entering streams using field surveys, analyses of chemical constituents, and numerical modeling. The mean NO3-N concentration in groundwater was 7.373 mg/L, which is approximately 1.9 times higher than concentrations found in stream water. The groundwater and stream water samples belonged to the Ca-HCO3 type. The concentration of NO3-N in groundwater tended to increase in the lowland areas downstream. There was seasonal variations of NO3-N in both the groundwater and stream water samples, with increases in concentration during the dry season (January-April) and decreases during the wet season (June-October). The NO3-N load in stream water to that in groundwater (R) was higher during the wet season (September) than the dry season (March), with R distinctly increasing in upstream areas relative to downstream areas, indicating that during the wet season, a large amount of NO3-N is introduced into stream water from groundwater. By analyzing the relationship between groundwater and stream water and through NO3-N transport modeling, it was revealed that in the watershed, the nitrate-N load in stream water is greatly augmented by inputs from groundwater, particularly in the middle and downstream areas.
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Affiliation(s)
- Chung-Mo Lee
- Department of Geological Sciences, Pusan National University, Busan, 46241, South Korea
| | - Se-Yeong Hamm
- Department of Geological Sciences, Pusan National University, Busan, 46241, South Korea.
| | - Jae-Yeol Cheong
- Korea Radioactive Waste Agency, Gyeongju, 38062, South Korea
| | - Kangjoo Kim
- Department of Environmental Engineering, Kunsan National University, Kunsan, 54150, South Korea
| | - Heesung Yoon
- Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources, Daejeon, 34132, South Korea
| | - MoonSu Kim
- Soil and Groundwater Division, National Institute of Environmental Research, Incheon, 22689, South Korea
| | - Jinsoo Kim
- Department of Spatial Information Engineering, Pukyong National University, Busan, 48513, South Korea
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23
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Li Y, Wang D, Chen S, Yu Z, Liu L, Wang M, Chen Z. N 2 fixation in urbanization area rivers: spatial-temporal variations and influencing factors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:7211-7221. [PMID: 31879888 DOI: 10.1007/s11356-019-06780-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
While nitrogen (N2) fixation is an important process in nitrogen (N) biogeochemical cycling, supplying a significant portion of the N in natural ecosystems, few quantitative constraints exist concerning its contribution to the N enrichment and export from river ecosystems. This study estimates the N2 fixation rates of urban rivers in the Yangtze Estuary area using acetylene reduction. The results demonstrate that the prominent spatiotemporal variability of river N2 fixation rates is driven by various environmental factors. River N2 fixation rates are significantly higher in the summer (90.57 ± 14.60 ngN·L-1·h-1) than in the winter (57.98 ± 15.73 ngN·L-1·h-1). Spatially, rivers draining urban and suburban areas have higher N2 fixation rates than those draining rural areas. The N2 fixation rates are positively correlated with the N2 fixing cyanobacteria density, water temperature, light, and the water phosphorus (P) concentration, but they are negatively correlated with the dissolved N concentration (NH4+-N and NO3--N). The N2 fixation rates annually range from 53.20 to 89.24 ngN·L-1·h-1 for all of the sampling rivers, which is equivalent to a depth integrated (0-0.6 m) N input of 0.163-0.274 gN·m-2·a-1. The determined annual N input via N2 fixation is generally higher than that of marine systems, but it is lower than that of eutrophic lakes. This study provides robust evidence that N2 fixation can supply a substantial portion of the N input to human-impacted river ecosystems, which has not been sufficiently accounted for when determining the N mass balance of riverine ecosystems. A high N2 fixation rate may increase the ratio of N to P input to river systems, and therefore render P the limiting factor in aquatic eutrophication.
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Affiliation(s)
- Yu Li
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
| | - Dongqi Wang
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China.
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China.
| | - Shu Chen
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
| | - Zhongjie Yu
- Department of Soil, Water, and Climate, University of Minnesota, St. Paul, MN, 55108, USA
| | - Lijie Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
| | - Meng Wang
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
| | - Zhenlou Chen
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China
- School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
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24
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King K, Cheruvelil KS, Pollard A. Drivers and spatial structure of abiotic and biotic properties of lakes, wetlands, and streams at the national scale. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01957. [PMID: 31240779 PMCID: PMC7337605 DOI: 10.1002/eap.1957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 05/21/2019] [Accepted: 06/11/2019] [Indexed: 05/31/2023]
Abstract
Broad-scale studies have improved our ability to make predictions about how freshwater biotic and abiotic properties will respond to changes in climate and land use intensification. Further, fine-scaled studies of lakes, wetlands, or streams have documented the important role of hydrologic connections for understanding many freshwater biotic and abiotic processes. However, lakes, wetlands, and streams are typically studied in isolation of one another at both fine and broad scales. Therefore, it is not known whether these three freshwater types (lakes, wetlands, and streams) respond similarly to ecosystem and watershed drivers nor how they may respond to future global stresses. In this study, we asked, do lake, wetland, and stream biotic and abiotic properties respond to similar ecosystem and watershed drivers and have similar spatial structure at the national scale? We answered this question with three U.S. conterminous data sets of freshwater ecosystems. We used random forest (RF) analysis to quantify the multi-scaled drivers related to variation in nutrients and biota in lakes, wetlands, and streams simultaneously; we used semivariogram analysis to quantify the spatial structure of biotic and abiotic properties and to infer possible mechanisms controlling the ecosystem properties of these freshwater types. We found that abiotic properties responded to similar drivers, had large ranges of spatial autocorrelation, and exhibited multi-scale spatial structure, regardless of freshwater type. However, the dominant drivers of variation in biotic properties depended on freshwater type and had smaller ranges of spatial autocorrelation. Our study is the first to document that drivers and spatial structure differ more between biotic and abiotic variables than across freshwater types, suggesting that some properties of freshwater ecosystems may respond similarly to future global changes.
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Affiliation(s)
- Katelyn King
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan 48824 USA
| | - Kendra Spence Cheruvelil
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan 48824 USA
- Lyman Briggs College, Michigan State University, East Lansing, Michigan 48824 USA
| | - Amina Pollard
- U.S. Environmental Protection Agency Office of Water, Washington, D.C. 20004 USA
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25
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Amos HM, Miniat CF, Lynch J, Compton J, Templer PH, Sprague LA, Shaw D, Burns D, Rea A, Whitall D, Myles L, Gay D, Nilles M, Walker J, Rose AK, Bales J, Deacon J, Pouyat R. What Goes Up Must Come Down: Integrating Air and Water Quality Monitoring for Nutrients. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:11441-11448. [PMID: 30230820 DOI: 10.1021/acs.est.8b03504] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Excess nitrogen and phosphorus ("nutrients") loadings continue to affect ecosystem function and human health across the U.S. Our ability to connect atmospheric inputs of nutrients to aquatic end points remains limited due to uncoupled air and water quality monitoring. Where connections exist, the information provides insights about source apportionment, trends, risk to sensitive ecosystems, and efficacy of pollution reduction efforts. We examine several issues driving the need for better integrated monitoring, including: coastal eutrophication, urban hotspots of deposition, a shift from oxidized to reduced nitrogen deposition, and the disappearance of pristine lakes. Successful coordination requires consistent data reporting; collocating deposition and water quality monitoring; improving phosphorus deposition measurements; and filling coverage gaps in urban corridors, agricultural areas, undeveloped watersheds, and coastal zones.
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Affiliation(s)
- Helen M Amos
- AAAS Science and Technology Policy Fellow hosted by U.S. Environmental Protection Agency , Washington , DC 20004 , United States
| | - Chelcy F Miniat
- U.S. Department of Agriculture , Office of the Chief Scientist , Washington , DC 20250 , United States
| | - Jason Lynch
- U.S. Environmental Protection Agency , Office of Air and Radiation , Washington , DC 20004 , United States
| | - Jana Compton
- U.S. Environmental Protection Agency , Western Ecology Division , Corvallis , Oregon 97333 , United States
| | - Pamela H Templer
- Boston University , Department of Biology , Boston , Massachusetts 02215 , United States
| | - Lori A Sprague
- U.S. Geological Survey, National Water Quality Program , Denver , Colorado 80225 , United States
| | - Denice Shaw
- U.S. Environmental Protection Agency , Office of Research and Development , Washington , DC 20004 , United States
| | - Doug Burns
- U.S. Geological Survey, New York Water Science Center , Troy , New York 12309 , United States
| | - Anne Rea
- U.S. Environmental Protection Agency , Office of Research and Development , Research Triangle Park , North Carolina 27711 , United States
| | - David Whitall
- National Oceanic and Atmospheric Administration, National Ocean Service , Silver Spring , Maryland 20910 , United States
| | - LaToya Myles
- National Oceanic and Atmospheric Administration, Air Resources Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - David Gay
- National Atmospheric Deposition Program, Wisconsin State Laboratory of Hygiene , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Mark Nilles
- U.S. Geological Survey, National Water Quality Program , Lakewood , Colorado 80225 , United States
| | - John Walker
- U.S. Environmental Protection Agency , Office of Research and Development , Research Triangle Park , North Carolina 27711 , United States
| | - Anita K Rose
- U.S. Department of Agriculture Forest Service , Air Resource Management , Washington , DC 20250 , United States
| | - Jerad Bales
- Consortium of Universities for the Advancement Hydrologic Science, Inc. , Cambridge , Massachusetts 02140 , United States
| | - Jeffrey Deacon
- U.S. Geological Survey, National Water Quality Program , Pembroke , New Hampshire 03275 , United States
| | - Richard Pouyat
- U.S. Department of Agriculture Forest Service , Research and Development , Washington , DC 20250 , United States
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