1
|
Bieroza M, Hallberg L, Livsey J, Prischl LA, Wynants M. Recognizing Agricultural Headwaters as Critical Ecosystems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:4852-4858. [PMID: 38438992 PMCID: PMC10956425 DOI: 10.1021/acs.est.3c10165] [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: 12/05/2023] [Revised: 02/23/2024] [Accepted: 02/23/2024] [Indexed: 03/06/2024]
Abstract
Agricultural headwaters are positioned at the interface between terrestrial and aquatic ecosystems and, therefore, at the margins of scientific disciplines. They are deemed devoid of biodiversity and too polluted by ecologists, overlooked by hydrologists, and are perceived as a nuisance by landowners and water authorities. While agricultural streams are widespread and represent a major habitat in terms of stream length, they remain understudied and thereby undervalued. Agricultural headwater streams are significantly modified and polluted but at the same time are the critical linkages among land, air, and water ecosystems. They exhibit the largest variation in streamflow, water quality, and greenhouse gas emission with cascading effects on the entire stream networks, yet they are underrepresented in monitoring, remediation, and restoration. Therefore, we call for more intense efforts to characterize and understand the inherent variability and sensitivity of these ecosystems to global change drivers through scientific and regulatory monitoring and to improve their ecosystem conditions and functions through purposeful and evidence-based remediation.
Collapse
Affiliation(s)
- Magdalena Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden
| | - Lukas Hallberg
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden
| | - John Livsey
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden
| | - Laura-Ainhoa Prischl
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden
| | - Maarten Wynants
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden
| |
Collapse
|
2
|
Khandelwal A, Castillo T, González-Pinzón R. Development of The Navigator: A Lagrangian sensing system to characterize surface freshwater ecosystems. WATER RESEARCH 2023; 245:120577. [PMID: 37688858 DOI: 10.1016/j.watres.2023.120577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/10/2023] [Accepted: 09/04/2023] [Indexed: 09/11/2023]
Abstract
Most freshwater aquatic studies rely on Eulerian monitoring, i.e., water quality and quantity are monitored using grab samples or semi-continuous sensors deployed at fixed cross-sections. While Eulerian monitoring is practical, it provides a limited understanding of spatial and temporal heterogeneity. We designed and built The Navigator, a Lagrangian (i.e., along a flow path) monitoring system that offers cost-effective solutions for in-situ, real-time data collection in surface freshwater ecosystems. The Navigator features a suite of technologies, including an autonomous surface vehicle with GPS and LTE connectivity, water quality sensors, a depth sonar, a camera, and a webpage dashboard to visualize real-time data. With these technologies, The Navigator provides insight into where, how, and why water quality and quantity change over time and space as it moves with the current or follows user-specified pathways. We tested The Navigator monitoring water quality parameters at high spatial-temporal resolution in multiple surface water bodies in New Mexico (USA) to: (1) identify water quality changes associated with land use changes along a 7th-order reach in the Rio Grande, (2) identify the fate of wildfire disturbances ∼175 km downstream of a burned watershed affected by the largest wildfire ever recorded in the state, (3) monitor the water quality of a recreational fishing pond in the City of Albuquerque. Our three successful tests confirm that The Navigator is an affordable (USD 5,101 in 2023) monitoring system that can be used to address questions involving mass and energy balances in surface waters.
Collapse
Affiliation(s)
- Aashish Khandelwal
- Gerald May Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, NM, USA.
| | - Tzion Castillo
- Gerald May Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, NM, USA; Electrical Engineering, University of New Mexico, Albuquerque, NM, USA
| | - Ricardo González-Pinzón
- Gerald May Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, NM, USA.
| |
Collapse
|
3
|
Severe E, Errigo IM, Proteau M, Sayedi SS, Kolbe T, Marçais J, Thomas Z, Petton C, Rouault F, Vautier C, de Dreuzy JR, Moatar F, Aquilina L, Wood RL, LaBasque T, Lécuyer C, Pinay G, Abbott BW. Deep denitrification: Stream and groundwater biogeochemistry reveal contrasted but connected worlds above and below. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 880:163178. [PMID: 37023812 DOI: 10.1016/j.scitotenv.2023.163178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 03/25/2023] [Accepted: 03/26/2023] [Indexed: 05/27/2023]
Abstract
Excess nutrients from agricultural and urban development have created a cascade of ecological crises around the globe. Nutrient pollution has triggered eutrophication in most freshwater and coastal ecosystems, contributing to a loss in biodiversity, harm to human health, and trillions in economic damage every year. Much of the research conducted on nutrient transport and retention has focused on surface environments, which are both easy to access and biologically active. However, surface characteristics of watersheds, such as land use and network configuration, often do not explain the variation in nutrient retention observed in rivers, lakes, and estuaries. Recent research suggests subsurface processes and characteristics may be more important than previously thought in determining watershed-level nutrient fluxes and removal. In a small watershed in western France, we used a multi-tracer approach to compare surface and subsurface nitrate dynamics at commensurate spatiotemporal scales. We combined 3-D hydrological modeling with a rich biogeochemical dataset from 20 wells and 15 stream locations. Water chemistry in the surface and subsurface showed high temporal variability, but groundwater was substantially more spatially variable, attributable to long transport times (10-60 years) and patchy distribution of the iron and sulfur electron donors fueling autotrophic denitrification. Isotopes of nitrate and sulfate revealed fundamentally different processes dominating the surface (heterotrophic denitrification and sulfate reduction) and subsurface (autotrophic denitrification and sulfate production). Agricultural land use was associated with elevated nitrate in surface water, but subsurface nitrate concentration was decoupled from land use. Dissolved silica and sulfate are affordable tracers of residence time and nitrogen removal that are relatively stable in surface and subsurface environments. Together, these findings reveal distinct but adjacent and connected biogeochemical worlds in the surface and subsurface. Characterizing how these worlds are linked and decoupled is critical to meeting water quality targets and addressing water issues in the Anthropocene.
Collapse
Affiliation(s)
- Emilee Severe
- Lancaster Environmental Centre, Lancaster University, Lancaster, UK; Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Isabella M Errigo
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA; Grupo de Investigación en Biodiversidad, Medio Ambiente y Salud (BIOMAS), Facultad de Ingenierías y Ciencas Aplicadas, Universidad de Las Américas, Quito, Ecuador
| | - Mary Proteau
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Sayedeh Sara Sayedi
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Tamara Kolbe
- Section of Hydrogeology and Hydrochemistry, Institute of Geology, Faculty of Geoscience, Geoengineering and Mining, TU Bergakademie Freiberg, Freiberg, Germany
| | - Jean Marçais
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAe), RiverLy, Centre de Lyon-Villeurbanne, 69625 Villeurbanne, France
| | - Zahra Thomas
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAe), Sol Agro et Hydrosystème Spatialisation, UMR 1069, Agrocampus Ouest, 35042 Rennes, France
| | - Christophe Petton
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000 Rennes, France
| | - François Rouault
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAe), Sol Agro et Hydrosystème Spatialisation, UMR 1069, Agrocampus Ouest, 35042 Rennes, France
| | - Camille Vautier
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000 Rennes, France
| | - Jean-Raynald de Dreuzy
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000 Rennes, France; Univ Rennes, CNRS, OSUR (Observatoire des sciences de l'univers de Rennes), UMS 3343, 35000 Rennes, France
| | - Florentina Moatar
- RiverLy, INRAE, Centre de Lyon-Grenoble Auvergne-Rhône-Alpes, Lyon, France
| | - Luc Aquilina
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000 Rennes, France
| | - Rachel L Wood
- Department of Biology, Brigham Young University, Provo, UT, USA
| | - Thierry LaBasque
- Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 35000 Rennes, France
| | | | - Gilles Pinay
- Environnement, Ville & Société (EVS UMR5600), Centre National de la Recherche Scientifique (CNRS), Lyon, France
| | - Benjamin W Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA.
| |
Collapse
|
4
|
Bieroza M, Acharya S, Benisch J, ter Borg RN, Hallberg L, Negri C, Pruitt A, Pucher M, Saavedra F, Staniszewska K, van’t Veen SGM, Vincent A, Winter C, Basu NB, Jarvie HP, Kirchner JW. Advances in Catchment Science, Hydrochemistry, and Aquatic Ecology Enabled by High-Frequency Water Quality Measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4701-4719. [PMID: 36912874 PMCID: PMC10061935 DOI: 10.1021/acs.est.2c07798] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 03/03/2023] [Accepted: 03/03/2023] [Indexed: 06/18/2023]
Abstract
High-frequency water quality measurements in streams and rivers have expanded in scope and sophistication during the last two decades. Existing technology allows in situ automated measurements of water quality constituents, including both solutes and particulates, at unprecedented frequencies from seconds to subdaily sampling intervals. This detailed chemical information can be combined with measurements of hydrological and biogeochemical processes, bringing new insights into the sources, transport pathways, and transformation processes of solutes and particulates in complex catchments and along the aquatic continuum. Here, we summarize established and emerging high-frequency water quality technologies, outline key high-frequency hydrochemical data sets, and review scientific advances in key focus areas enabled by the rapid development of high-frequency water quality measurements in streams and rivers. Finally, we discuss future directions and challenges for using high-frequency water quality measurements to bridge scientific and management gaps by promoting a holistic understanding of freshwater systems and catchment status, health, and function.
Collapse
Affiliation(s)
- Magdalena Bieroza
- Department
of Soil and Environment, SLU, Box 7014, Uppsala 750
07 Sweden
| | - Suman Acharya
- Department
of Environment and Genetics, School of Agriculture, Biomedicine and
Environment, La Trobe University, Albury/Wodonga Campus, Victoria 3690, Australia
| | - Jakob Benisch
- Institute
for Urban Water Management, TU Dresden, Bergstrasse 66, Dresden 01068, Germany
| | | | - Lukas Hallberg
- Department
of Soil and Environment, SLU, Box 7014, Uppsala 750
07 Sweden
| | - Camilla Negri
- Environment
Research Centre, Teagasc, Johnstown Castle, Wexford Y35 Y521, Ireland
- The
James
Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
- School
of
Archaeology, Geography and Environmental Science, University of Reading, Whiteknights, Reading RG6 6AB, United Kingdom
| | - Abagael Pruitt
- Department
of Biological Sciences, University of Notre
Dame, Notre
Dame, Indiana 46556, United States
| | - Matthias Pucher
- Institute
of Hydrobiology and Aquatic Ecosystem Management, Vienna University of Natural Resources and Life Sciences, Gregor Mendel Straße 33, Vienna 1180, Austria
| | - Felipe Saavedra
- Department
for Catchment Hydrology, Helmholtz Centre
for Environmental Research - UFZ, Theodor-Lieser-Straße 4, Halle (Saale) 06120, Germany
| | - Kasia Staniszewska
- Department
of Earth and Atmospheric Sciences, University
of Alberta, Edmonton, Alberta T6G 2E3, Canada
| | - Sofie G. M. van’t Veen
- Department
of Ecoscience, Aarhus University, Aarhus 8000, Denmark
- Envidan
A/S, Silkeborg 8600, Denmark
| | - Anna Vincent
- Department
of Biological Sciences, University of Notre
Dame, Notre
Dame, Indiana 46556, United States
| | - Carolin Winter
- Environmental
Hydrological Systems, University of Freiburg, Friedrichstraße 39, Freiburg 79098, Germany
- Department
of Hydrogeology, Helmholtz Centre for Environmental
Research - UFZ, Permoserstr.
15, Leipzig 04318, Germany
| | - Nandita B. Basu
- Department
of Civil and Environmental Engineering and Department of Earth and
Environmental Sciences, and Water Institute, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Helen P. Jarvie
- Water Institute
and Department of Geography and Environmental Management, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - James W. Kirchner
- Department
of Environmental System Sciences, ETH Zurich, Zurich CH-8092, Switzerland
- Swiss
Federal Research Institute WSL, Birmensdorf CH-8903, Switzerland
| |
Collapse
|
5
|
Lee RM, Griffin N, Jones E, Abbott BW, Frei RJ, Bratsman S, Proteau M, Errigo IM, Shogren A, Bowden WB, Zarnetske JP, Aanderud ZT. Bacterioplankton dispersal and biogeochemical function across Alaskan Arctic catchments. Environ Microbiol 2022; 24:5690-5706. [PMID: 36273269 DOI: 10.1111/1462-2920.16259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 10/21/2022] [Indexed: 01/12/2023]
Abstract
In Arctic catchments, bacterioplankton are dispersed through soils and streams, both of which freeze and thaw/flow in phase, seasonally. To characterize this dispersal and its potential impact on biogeochemistry, we collected bacterioplankton and measured stream physicochemistry during snowmelt and after vegetation senescence across multiple stream orders in alpine, tundra, and tundra-dominated-by-lakes catchments. In all catchments, differences in community composition were associated with seasonal thaw, then attachment status (i.e. free floating or sediment associated), and then stream order. Bacterioplankton taxonomic diversity and richness were elevated in sediment-associated fractions and in higher-order reaches during snowmelt. Families Chthonomonadaceae, Pyrinomonadaceae, and Xiphinematobacteraceae were abundantly different across seasons, while Flavobacteriaceae and Microscillaceae were abundantly different between free-floating and sediment-associated fractions. Physicochemical data suggested there was high iron (Fe+ ) production (alpine catchment); Fe+ production and chloride (Cl- ) removal (tundra catchment); and phosphorus (SRP) removal and ammonium (NH4 + ) production (lake catchment). In tundra landscapes, these 'hot spots' of Fe+ production and Cl- removal accompanied shifts in species richness, while SRP promoted the antecedent community. Our findings suggest that freshet increases bacterial dispersal from headwater catchments to receiving catchments, where bacterioplankton-mineral relations stabilized communities in free-flowing reaches, but bacterioplankton-nutrient relations stabilized those punctuated by lakes.
Collapse
Affiliation(s)
- Raymond M Lee
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Natasha Griffin
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvalis, Oregon, USA
| | - Erin Jones
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Benjamin W Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Rebecca J Frei
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Samuel Bratsman
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Mary Proteau
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Isabella M Errigo
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| | - Arial Shogren
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama, USA
| | - William B Bowden
- The Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, Vermont, USA
| | - Jay P Zarnetske
- Department of Earth and Environmental Sciences, Michigan State University, East Lansing, Michigan, USA
| | - Zachary T Aanderud
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, USA
| |
Collapse
|
6
|
Shinohara N, Nakadai R, Suzuki Y, Terui A. Spatiotemporal dimensions of community assembly. POPUL ECOL 2022. [DOI: 10.1002/1438-390x.12144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Naoto Shinohara
- Graduate School of Life Sciences Tohoku University Sendai Japan
- Faculty of Agriculture and Life Science Hirosaki University Hirosaki Japan
| | - Ryosuke Nakadai
- Biodiversity Division National Institute for Environmental Studies Tsukuba Japan
| | - Yuka Suzuki
- Department of Computational Biology Institut Pasteur, Université de Paris Paris France
| | - Akira Terui
- Department of Biology University of North Carolina at Greensboro Greensboro North Carolina USA
| |
Collapse
|
7
|
Grac C, Braud A, Gançarski P, Herrmann A, Ber FL. Comparing the physico-chemistry dynamics of running waters (North-East of France) based on sequence clustering. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
8
|
Hallberg L, Hallin S, Bieroza M. Catchment controls of denitrification and nitrous oxide production rates in headwater remediated agricultural streams. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156513. [PMID: 35679930 DOI: 10.1016/j.scitotenv.2022.156513] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
Heavily modified headwater streams and open ditches carry high nitrogen loads from agricultural soils that sustain eutrophication and poor water quality in downstream aquatic ecosystems. To remediate agricultural streams and reduce the export of nitrate (NO3-), phosphorus and suspended sediments, two-stage ditches with constructed floodplains can be implemented as countermeasures. By extending hydrological connectivity between the stream channel and riparian corridor within constructed floodplains, these remediated ditches enhance the removal of NO3- via the microbial denitrification process. Ten remediated ditches were paired with upstream trapezoidal ditches in Sweden across different soils and land uses to measure the capacity for denitrification and nitrous oxide (N2O) production and yields under denitrifying conditions in stream and floodplain sediments. To examine the controls for denitrification, water quality was monitored monthly and flow discharge continuously along reaches. Floodplain sediments accounted for 33 % of total denitrification capacity of remediated ditches, primarily controlled by inundation and stream NO3- concentrations. Despite reductions in flow-weighted NO3- concentrations along reaches, NO3- removal in remediated ditches via denitrification can be masked by inputs of NO3--rich groundwaters, typical of intensively managed agricultural landscapes. Although N2O production rates were 50 % lower in floodplains compared to the stream, remediated ditches emitted more N2O than conventional trapezoidal ditches. Higher denitrification rates and reductions of N2O proportions were predicted by catchments with loamy soils, higher proportions of agricultural land use and lower floodplain elevations. For realizing enhanced NO3- removal from floodplains and avoiding increased N2O emissions, soil type, land use and the design of floodplains need to be considered when implementing remediated streams. Further, we stress the need for assessing the impact of stream remediation in the context of broader catchment processes, to determine the overall potential for improving water quality.
Collapse
Affiliation(s)
- Lukas Hallberg
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | - Sara Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Magdalena Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| |
Collapse
|
9
|
Edmonds JW, King KBS, Neely MB, Hensley RT, Goodman KJ, Cawley KM. Using large, open datasets to understand spatial and temporal patterns in lotic ecosystems:
NEON
case studies. Ecosphere 2022. [DOI: 10.1002/ecs2.4102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Jennifer W. Edmonds
- Department of Physical and Life Sciences Nevada State College Henderson Nevada USA
| | - Katelyn B. S. King
- Department of Fisheries and Wildlife Michigan State University East Lansing Michigan USA
| | | | - Robert T. Hensley
- Battelle, National Ecological Observatory Network Boulder Colorado USA
| | - Keli J. Goodman
- Battelle, National Ecological Observatory Network Boulder Colorado USA
| | - Kaelin M. Cawley
- Battelle, National Ecological Observatory Network Boulder Colorado USA
| |
Collapse
|
10
|
An Assessment of the Impacts of Snowmelt Rate and Continuity Shifts on Streamflow Dynamics in Three Alpine Watersheds in the Western U.S. WATER 2022. [DOI: 10.3390/w14071095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In semiarid to arid regions of the western U.S., river flow availability and variability are highly subject to shifts in snow accumulation and ablation in alpine watersheds. This study aims to examine how shifts in snowmelt rate (SMR) and snow continuity, an indicator of the consistent existence of snow on the ground, affect snow-driven streamflow dynamics in three alpine watersheds in the U.S. Great Basin. To achieve this end, the coupled hydro-ecological simulation system (CHESS) is used to simulate river flow dynamics, and multiple snow metrics are calculated to quantify the variation of SMR and snow continuity, the latter of which is measured by snow persistence (SP), snow residence time (SRT), and snow season length (SSL). Then, a new approach is proposed to partition streamflow into snow-driven and rain-driven streamflow. The statistical analyses indicate that the three alpine watersheds experienced a downward trend in SP, SRT, SSL, and SMR during the study period of 1990–2016 due to regional warming. As a result, the decrease in SMR and the decline in snow continuity shifted the occurrence day of 25% and 50% of the snow-driven cumulative discharge, as well as peak discharge, toward an earlier occurrence. Moreover, the magnitudes of snow-driven annual streamflow, summer baseflow, and peak discharge also decreased due to the declined snow continuity and the reduced SMR. Overall, by using multiple snow and flow metrics, and by partitioning streamflow into snow-driven and rain-driven flow via the newly proposed approach, we found that SMR and snow continuity determine the streamflow hydrographs and magnitudes in the three alpine watersheds. Given that warming can significantly affect snow dynamics in alpine watersheds in semiarid to arid regions, this has important implications for water resource management in the snow-dominated region when facing future climate warming.
Collapse
|
11
|
Gong C, Jiao R, Yan W, Yu Q, Li Q, Zhang P, Li Y, Wang D. Enhanced chemodiversity, distinctive molecular signature and diurnal dynamics of dissolved organic matter in streams of two headwater catchments, Southeastern China. WATER RESEARCH 2022; 211:118052. [PMID: 35065339 DOI: 10.1016/j.watres.2022.118052] [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: 10/08/2021] [Revised: 01/05/2022] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
Dissolved organic matter (DOM) is a complicated assembly of organic molecules, including thousands of molecules with various structures and properties. However, how the stream DOM sources respond to carbon compositions and the transformation processes remains unclear. In this study, the chemical characteristics and spectral and mass spectrometry (FT-ICR MS) of DOM were analyzed. Six sampling points of headwater stream (HWSs) were sampled, and an effluent polluted stream (WSR) and a main stream of the Changjiang River (DT) were also sampled for comparison. In situ degradation experiments and FT-ICR MS analysis were also performed to observe the dynamic processes of DOM in HWS. The results showed that the anthropogenic markers of sewage (i.e. sulfur (S) compounds and marker from antibiotics and estrogen) in HWS were higher than those in DT. The molecular weight decreased while the degradation products (S-containing compounds and unsaturated compounds (HU)) increased after in situ degradation due to the influence of both the photodegradation and biodegradation process. In addition, the KMD plots showed that the DOM homologue intensities in range 400-600 Da changed significantly after demethylation by biodegradation. The components of highly refractory substances and the degradation degree of DOM in DT was higher than that in HWS. We extracted the refractory DOM pool in HWS, which was mainly small molecular with molecular weights < 600 Da. These molecular will be difficult to remove in traditional drinking water treatment processes and easily produced disinfection byproducts (DBPs). This study emphasized the necessity of identifying the sources and transformation processes of DOM in HWS and clarified the types and characteristics of DOM that should be considered in future drinking water treatment.
Collapse
Affiliation(s)
- Chen Gong
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruyuan Jiao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu city, Zhejiang Province, 322000, China
| | - Weijin Yan
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Qibiao Yu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qingqian Li
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Peipei Zhang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yanqiang Li
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Dongsheng Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu city, Zhejiang Province, 322000, China.
| |
Collapse
|
12
|
Frei RJ, Lawson GM, Norris AJ, Cano G, Vargas MC, Kujanpää E, Hopkins A, Brown B, Sabo R, Brahney J, Abbott BW. Limited progress in nutrient pollution in the U.S. caused by spatially persistent nutrient sources. PLoS One 2021; 16:e0258952. [PMID: 34843503 PMCID: PMC8629290 DOI: 10.1371/journal.pone.0258952] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 10/10/2021] [Indexed: 01/01/2023] Open
Abstract
Human agriculture, wastewater, and use of fossil fuels have saturated ecosystems with nitrogen and phosphorus, threatening biodiversity and human water security at a global scale. Despite efforts to reduce nutrient pollution, carbon and nutrient concentrations have increased or remained high in many regions. Here, we applied a new ecohydrological framework to ~12,000 water samples collected by the U.S. Environmental Protection Agency from streams and lakes across the contiguous U.S. to identify spatial and temporal patterns in nutrient concentrations and leverage (an indicator of flux). For the contiguous U.S. and within ecoregions, we quantified trends for sites sampled repeatedly from 2000 to 2019, the persistence of spatial patterns over that period, and the patch size of nutrient sources and sinks. While we observed various temporal trends across ecoregions, the spatial patterns of nutrient and carbon concentrations in streams were persistent across and within ecoregions, potentially because of historical nutrient legacies, consistent nutrient sources, and inherent differences in nutrient removal capacity for various ecosystems. Watersheds showed strong critical source area dynamics in that 2-8% of the land area accounted for 75% of the estimated flux. Variability in nutrient contribution was greatest in catchments smaller than 250 km2 for most parameters. An ensemble of four machine learning models confirmed previously observed relationships between nutrient concentrations and a combination of land use and land cover, demonstrating how human activity and inherent nutrient removal capacity interactively determine nutrient balance. These findings suggest that targeted nutrient interventions in a small portion of the landscape could substantially improve water quality at continental scales. We recommend a dual approach of first prioritizing the reduction of nutrient inputs in catchments that exert disproportionate influence on downstream water chemistry, and second, enhancing nutrient removal capacity by restoring hydrological connectivity both laterally and vertically in stream networks.
Collapse
Affiliation(s)
- Rebecca J. Frei
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Gabriella M. Lawson
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Adam J. Norris
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Gabriel Cano
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Maria Camila Vargas
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Elizabeth Kujanpää
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Austin Hopkins
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Brian Brown
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Robert Sabo
- United States Environmental Protection Agency, Washington, D. C., United States of America
| | - Janice Brahney
- Department of Watershed Sciences and Ecology Center, Utah State University, Logan, Utah, United States of America
| | - Benjamin W. Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| |
Collapse
|
13
|
Terui A, Kim S, Dolph CL, Kadoya T, Miyazaki Y. Emergent dual scaling of riverine biodiversity. Proc Natl Acad Sci U S A 2021; 118:e2105574118. [PMID: 34795054 PMCID: PMC8617499 DOI: 10.1073/pnas.2105574118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2021] [Indexed: 11/18/2022] Open
Abstract
A prevailing paradigm suggests that species richness increases with area in a decelerating way. This ubiquitous power law scaling, the species-area relationship, has formed the foundation of many conservation strategies. In spatially complex ecosystems, however, the area may not be the sole dimension to scale biodiversity patterns because the scale-invariant complexity of fractal ecosystem structure may drive ecological dynamics in space. Here, we use theory and analysis of extensive fish community data from two distinct geographic regions to show that riverine biodiversity follows a robust scaling law along the two orthogonal dimensions of ecosystem size and complexity (i.e., the dual scaling law). In river networks, the recurrent merging of various tributaries forms fractal branching systems, where the prevalence of branching (ecosystem complexity) represents a macroscale control of the ecosystem's habitat heterogeneity. In the meantime, ecosystem size dictates metacommunity size and total habitat diversity, two factors regulating biodiversity in nature. Our theory predicted that, regardless of simulated species' traits, larger and more branched "complex" networks support greater species richness due to increased space and environmental heterogeneity. The relationships were linear on logarithmic axes, indicating power law scaling by ecosystem size and complexity. In support of this theoretical prediction, the power laws have consistently emerged in riverine fish communities across the study regions (Hokkaido Island in Japan and the midwestern United States) despite hosting different fauna with distinct evolutionary histories. The emergence of dual scaling law may be a pervasive property of branching networks with important implications for biodiversity conservation.
Collapse
Affiliation(s)
- Akira Terui
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27412;
| | - Seoghyun Kim
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27412
| | - Christine L Dolph
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN 55108
| | - Taku Kadoya
- Biodiversity Division, National Institute for Environmental Studies, Tsukuba 305-8506, Japan
| | - Yusuke Miyazaki
- Department of Child Education and Welfare, Shiraume Gakuen College, Tokyo 187-8570, Japan
| |
Collapse
|
14
|
Bieroza MZ, Bol R, Glendell M. What is the deal with the Green Deal: Will the new strategy help to improve European freshwater quality beyond the Water Framework Directive? THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 791:148080. [PMID: 34126496 DOI: 10.1016/j.scitotenv.2021.148080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/21/2021] [Accepted: 05/22/2021] [Indexed: 06/12/2023]
Abstract
Agricultural land use covers almost half of the EU territory and reducing nutrient and pesticide losses to freshwaters is central to existing EU policy. However, the progress of improving freshwater quality and reducing eutrophication is slow and lags behind targets. The Green Deal is a key element of the EU plans to implement the United Nation's Sustainable Development Goals. Here, we discuss the opportunities that the Green Deal and associated strategies may provide for the achievement of the water quality goals of the Water Framework Directive in agricultural landscapes. We welcome Green Deal's aspirational stated goals. However, the reliance of mitigation of diffuse agricultural pollution on the reform of the Common Agricultural Policy represents grave risks for practical implementation and the achievement of the Green Deal objectives. We also argue that the new strategies should be targeted at tackling and understanding the sources of water quality problems along the full pollution continuum. To maximise the opportunities for tackling diffuse pollution from agricultural land use and achieving the delayed water quality targets, we stress that a range of targeted new instruments will be needed to close the gaps in the pollution continuum 'from source to impact'. These gaps include: (I) smart and standardised monitoring of the impacts of proposed eco-schemes and agri-environment-climate measures, (ii) active restoration of agricultural streams and ditches and their floodplains to reduce secondary pollution sources, (iii) options to draw down nutrient levels to or below the agronomic optimum that reduce legacy sources, (iv) integrating farm-scale and catchment-scale analysis of trade-offs in reducing different pollutants and their combined effects, and finally (v) accounting for emerging pressures to freshwater quality due to climate change. Incorporation of the pollution continuum framework into tackling diffuse agricultural pollution will ensure that the European water-related policy goals are achieved.
Collapse
Affiliation(s)
- M Z Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden.
| | - R Bol
- Forschungszentrum Jülich IBG-3, Wilhelm-Johnen-Straße, 52428 Jülich, Germany; School of Natural Sciences, Environment Centre Wales, Bangor University, Bangor LL57 2UW, UK
| | - M Glendell
- The James Hutton Institute, Environmental and Biochemical Sciences Group, Craigiebuckler, Aberdeen AB15 8QH, Scotland, UK
| |
Collapse
|
15
|
A Classification Framework to Assess Ecological, Biogeochemical, and Hydrologic Synchrony and Asynchrony. Ecosystems 2021; 25:989-1005. [DOI: 10.1007/s10021-021-00700-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
16
|
A riverscape approach reveals downstream propagation of stream thermal responses to riparian thinning at multiple scales. Ecosphere 2021. [DOI: 10.1002/ecs2.3775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
17
|
Walker RH, Ashton MJ, Cashman MJ, Fanelli RM, Krause KP, Noe GB, Maloney KO. Time marches on, but do the causal pathways driving instream habitat and biology remain consistent? THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 789:147985. [PMID: 34323823 DOI: 10.1016/j.scitotenv.2021.147985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/16/2021] [Accepted: 05/19/2021] [Indexed: 06/13/2023]
Abstract
Stream ecosystems are complex networks of interacting terrestrial and aquatic drivers. To untangle these ecological networks, efforts evaluating the direct and indirect effects of landscape, climate, and instream predictors on biological condition through time are needed. We used structural equation modeling and leveraged a stream survey program to identify and compare important predictors driving condition of benthic macroinvertebrate and fish assemblages. We used data resampled 14 years apart at 252 locations across Maryland, USA. Sample locations covered a wide range of conditions that varied spatiotemporally. Overall, the relationship directions were consistent between sample periods, but their relative strength varied temporally. For benthic macroinvertebrates, we found that the total effect of natural landscape (e.g., elevation, longitude, latitude, geology) and land use (i.e., forest, development, agriculture) predictors was 1.4 and 1.5 times greater in the late 2010s compared to the 2000s. Moreover, the total effect of water quality (e.g., total nitrogen and conductivity) and habitat (e.g., embeddedness, riffle quality) was 1.2 and 4.8 times lower in the 2010s, respectively. For fish assemblage condition, the total effect of land use-land cover predictors was 2.3 times greater in the 2010s compared to the 2000s, while the total effect of local habitat was 1.4 times lower in the 2010s, respectively. As expected, we found biological assemblages in catchments with more agriculture and urban development were generally comprised of tolerant, generalist species, while assemblages in catchments with greater forest cover had more-specialized, less-tolerant species (e.g., Ephemeroptera, Plecoptera, and Trichoptera taxa, clingers, benthic and lithophilic spawning fishes). Changes in the relative importance of landscape and land-use predictors suggest other correlated, yet unmeasured, proximal factors became more important over time. By untangling these ecological networks, stakeholders can gain a better understanding of the spatiotemporal relationships driving biological condition to implement management practices aimed at improving stream condition.
Collapse
Affiliation(s)
- Richard H Walker
- U.S. Geological Survey, Eastern Ecological Science Center at the Leetown Research Laboratory, Kearneysville, WV, USA.
| | - Matthew J Ashton
- Maryland Department of Natural Resources, Monitoring and Non-Tidal Assessment Division, Annapolis, MD, USA
| | - Matthew J Cashman
- U.S. Geological Survey, Maryland-Delaware-District of Columbia Water Science Center, Baltimore, MD, USA
| | - Rosemary M Fanelli
- U.S. Geological Survey, South Atlantic Water Science Center, Raleigh, NC, USA
| | - Kevin P Krause
- U.S. Geological Survey, Eastern Ecological Science Center at the Leetown Research Laboratory, Kearneysville, WV, USA
| | - Gregory B Noe
- U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, VA, USA
| | - Kelly O Maloney
- U.S. Geological Survey, Eastern Ecological Science Center at the Leetown Research Laboratory, Kearneysville, WV, USA
| |
Collapse
|
18
|
Crandall T, Jones E, Greenhalgh M, Frei RJ, Griffin N, Severe E, Maxwell J, Patch L, St. Clair SI, Bratsman S, Merritt M, Norris AJ, Carling GT, Hansen N, St. Clair SB, Abbott BW. Megafire affects stream sediment flux and dissolved organic matter reactivity, but land use dominates nutrient dynamics in semiarid watersheds. PLoS One 2021; 16:e0257733. [PMID: 34555099 PMCID: PMC8460006 DOI: 10.1371/journal.pone.0257733] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 09/08/2021] [Indexed: 01/05/2023] Open
Abstract
Climate change is causing larger wildfires and more extreme precipitation events in many regions. As these ecological disturbances increasingly coincide, they alter lateral fluxes of sediment, organic matter, and nutrients. Here, we report the stream chemistry response of watersheds in a semiarid region of Utah (USA) that were affected by a megafire followed by an extreme precipitation event in October 2018. We analyzed daily to hourly water samples at 10 stream locations from before the storm event until three weeks after its conclusion for suspended sediment, solute and nutrient concentrations, water isotopes, and dissolved organic matter concentration, optical properties, and reactivity. The megafire caused a ~2,000-fold increase in sediment flux and a ~6,000-fold increase in particulate carbon and nitrogen flux over the course of the storm. Unexpectedly, dissolved organic carbon (DOC) concentration was 2.1-fold higher in burned watersheds, despite the decreased organic matter from the fire. DOC from burned watersheds was 1.3-fold more biodegradable and 2.0-fold more photodegradable than in unburned watersheds based on 28-day dark and light incubations. Regardless of burn status, nutrient concentrations were higher in watersheds with greater urban and agricultural land use. Likewise, human land use had a greater effect than megafire on apparent hydrological residence time, with rapid stormwater signals in urban and agricultural areas but a gradual stormwater pulse in areas without direct human influence. These findings highlight how megafires and intense rainfall increase short-term particulate flux and alter organic matter concentration and characteristics. However, in contrast with previous research, which has largely focused on burned-unburned comparisons in pristine watersheds, we found that direct human influence exerted a primary control on nutrient status. Reducing anthropogenic nutrient sources could therefore increase socioecological resilience of surface water networks to changing wildfire regimes.
Collapse
Affiliation(s)
- Trevor Crandall
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
- Cimarron Valley Research Station, Oklahoma State University, Perkins, Oklahoma, United States of America
| | - Erin Jones
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Mitchell Greenhalgh
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Rebecca J. Frei
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Natasha Griffin
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Emilee Severe
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Jordan Maxwell
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Leika Patch
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - S. Isaac St. Clair
- Department of Statistics, Brigham Young University, Provo, Utah, United States of America
| | - Sam Bratsman
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Marina Merritt
- Department of Chemical Engineering, Brigham Young University, Provo, Utah, United States of America
| | - Adam J. Norris
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Gregory T. Carling
- Department of Geological Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Neil Hansen
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Samuel B. St. Clair
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Benjamin W. Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| |
Collapse
|
19
|
Jones EF, Frei RJ, Lee RM, Maxwell JD, Shoemaker R, Follett AP, Lawson GM, Malmfeldt M, Watts R, Aanderud ZT, Allred C, Asay AT, Buhman M, Burbidge H, Call A, Crandall T, Errigo I, Griffin NA, Hansen NC, Howe JC, Meadows EL, Kujanpaa E, Lange L, Nelson ML, Norris AJ, Ostlund E, Suiter NJ, Tanner K, Tolworthy J, Vargas MC, Abbott BW. Citizen science reveals unexpected solute patterns in semiarid river networks. PLoS One 2021; 16:e0255411. [PMID: 34411107 PMCID: PMC8376020 DOI: 10.1371/journal.pone.0255411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 07/15/2021] [Indexed: 11/18/2022] Open
Abstract
Human modification of water and nutrient flows has resulted in widespread degradation of aquatic ecosystems. The resulting global water crisis causes millions of deaths and trillions of USD in economic damages annually. Semiarid regions have been disproportionately affected because of high relative water demand and pollution. Many proven water management strategies are not fully implemented, partially because of a lack of public engagement with freshwater ecosystems. In this context, we organized a large citizen science initiative to quantify nutrient status and cultivate connection in the semiarid watershed of Utah Lake (USA). Working with community members, we collected samples from ~200 locations throughout the 7,640 km2 watershed on a single day in the spring, summer, and fall of 2018. We calculated ecohydrological metrics for nutrients, major ions, and carbon. For most solutes, concentration and leverage (influence on flux) were highest in lowland reaches draining directly to the lake, coincident with urban and agricultural sources. Solute sources were relatively persistent through time for most parameters despite substantial hydrological variation. Carbon, nitrogen, and phosphorus species showed critical source area behavior, with 10-17% of the sites accounting for most of the flux. Unlike temperate watersheds, where spatial variability often decreases with watershed size, longitudinal variability showed an hourglass shape: high variability among headwaters, low variability in mid-order reaches, and high variability in tailwaters. This unexpected pattern was attributable to the distribution of human activity and hydrological complexity associated with return flows, losing river reaches, and diversions in the tailwaters. We conclude that participatory science has great potential to reveal ecohydrological patterns and rehabilitate individual and community relationships with local ecosystems. In this way, such projects represent an opportunity to both understand and improve water quality in diverse socioecological contexts.
Collapse
Affiliation(s)
- Erin Fleming Jones
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Rebecca J. Frei
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Raymond M. Lee
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Jordan D. Maxwell
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Rhetta Shoemaker
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Andrew P. Follett
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Gabriella M. Lawson
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Madeleine Malmfeldt
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Rachel Watts
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Zachary T. Aanderud
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Carter Allred
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Allison Tuttle Asay
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Madeline Buhman
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Hunter Burbidge
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Amber Call
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Trevor Crandall
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Isabella Errigo
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Natasha A. Griffin
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Neil C. Hansen
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Jansen C. Howe
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Emily L. Meadows
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Elizabeth Kujanpaa
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Leslie Lange
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Monterey L. Nelson
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Adam J. Norris
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Elysse Ostlund
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Nicholas J. Suiter
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Kaylee Tanner
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Joseph Tolworthy
- Department of Geology, Brigham Young University, Provo, Utah, United States of America
| | - Maria Camila Vargas
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| | - Benjamin W. Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, Utah, United States of America
| |
Collapse
|
20
|
Meyer AM, Fuenfrocken E, Kautenburger R, Cairault A, Beck HP. Detecting pollutant sources and pathways: High-frequency automated online monitoring in a small rural French/German transborder catchment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 290:112619. [PMID: 33971450 DOI: 10.1016/j.jenvman.2021.112619] [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: 11/04/2020] [Revised: 04/09/2021] [Accepted: 04/10/2021] [Indexed: 06/12/2023]
Abstract
Great temporal and spatial variability of inputs make comprehensive monitoring in small and middle sized rivers difficult. In this study, relevant inputs in a small river were recorded with suitable online monitoring equipment coupled in mobile water quality monitoring stations, the study area being a transborder catchment with French and German (Saarland federal state) subcatchments. In addition to a pronounced spatial variability necessitating a denser net of measuring points this catchment has also to be assessed in the light of different national regulations. To identify individual pollution sources and weigh their relative importance, relevant parameters were recorded over a representative monitoring period of several months: phosphorus (P) as total phosphorus (TP) and total reactive P phosphorus (TRP), nitrate (NO3-N), ammonium (NH4-N), total organic carbon (TOC), temperature, oxygen (O2), pH, turbidity, and electrical conductivity (EC). The recorded data were subjected to adapted interpretation together with other catchment-related factors. In order to retrieve maximum information from the online data sets the relationships among certain parameter pairs were also analysed for both storm events and low flow periods. Comparison of loads at the different monitoring sites could reliably verify the majority of nutrient inputs originating in the French subcatchment. Additional sampling of output channels from sewage treatment works (STWs) in the Saarland subcatchment revealed that inputs from several decentralised STWs do not result in significant loads, as opposed to inputs from one STW in France. Our holistic approach provides a basis for adopting cost-effective measures to reduce loads in small river catchments as well as cross-border harmonisation of environmental policies.
Collapse
Affiliation(s)
- Angelika M Meyer
- Institute of Inorganic and Analytical Chemistry, Saarland University, Dudweiler Zeile 4, 66125, Saarbruecken, Germany.
| | - Elisabeth Fuenfrocken
- Institute of Inorganic and Analytical Chemistry, Saarland University, Dudweiler Zeile 4, 66125, Saarbruecken, Germany
| | - Ralf Kautenburger
- Institute of Inorganic Solid State Chemistry - WASTe-Elemental Analysis Group, Saarland University, Campus C4 1, 66123, Saarbruecken, Germany
| | - Alban Cairault
- Regional Natural Park of the Northern Vosges, 21, Rue Du Château, 67290, La Petite-Pierre, France
| | - Horst P Beck
- Institute of Inorganic and Analytical Chemistry, Saarland University, Dudweiler Zeile 4, 66125, Saarbruecken, Germany
| |
Collapse
|
21
|
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.
Collapse
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
| |
Collapse
|
22
|
Abbott BW, Rocha AV, Shogren A, Zarnetske JP, Iannucci F, Bowden WB, Bratsman SP, Patch L, Watts R, Fulweber R, Frei RJ, Huebner AM, Ludwig SM, Carling GT, O'Donnell JA. Tundra wildfire triggers sustained lateral nutrient loss in Alaskan Arctic. GLOBAL CHANGE BIOLOGY 2021; 27:1408-1430. [PMID: 33394532 DOI: 10.1111/gcb.15507] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/13/2020] [Indexed: 06/12/2023]
Abstract
Climate change is creating widespread ecosystem disturbance across the permafrost zone, including a rapid increase in the extent and severity of tundra wildfire. The expansion of this previously rare disturbance has unknown consequences for lateral nutrient flux from terrestrial to aquatic environments. Lateral loss of nutrients could reduce carbon uptake and slow recovery of already nutrient-limited tundra ecosystems. To investigate the effects of tundra wildfire on lateral nutrient export, we analyzed water chemistry in and around the 10-year-old Anaktuvuk River fire scar in northern Alaska. We collected water samples from 21 burned and 21 unburned watersheds during snowmelt, at peak growing season, and after plant senescence in 2017 and 2018. After a decade of ecosystem recovery, aboveground biomass had recovered in burned watersheds, but overall carbon and nitrogen remained ~20% lower, and the active layer remained ~10% deeper. Despite lower organic matter stocks, dissolved organic nutrients were substantially elevated in burned watersheds, with higher flow-weighted concentrations of organic carbon (25% higher), organic nitrogen (59% higher), organic phosphorus (65% higher), and organic sulfur (47% higher). Geochemical proxies indicated greater interaction with mineral soils in watersheds with surface subsidence, but optical analysis and isotopes suggested that recent plant growth, not mineral soil, was the main source of organic nutrients in burned watersheds. Burned and unburned watersheds had similar δ15 N-NO3 - , indicating that exported nitrogen was of preburn origin (i.e., not recently fixed). Lateral nitrogen flux from burned watersheds was 2- to 10-fold higher than rates of background nitrogen fixation and atmospheric deposition estimated in this area. These findings indicate that wildfire in Arctic tundra can destabilize nitrogen, phosphorus, and sulfur previously stored in permafrost via plant uptake and leaching. This plant-mediated nutrient loss could exacerbate terrestrial nutrient limitation after disturbance or serve as an important nutrient release mechanism during succession.
Collapse
Affiliation(s)
- Benjamin W Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Adrian V Rocha
- Department of Biological Sciences & the Environmental Change Initiative, University of Notre Dame, Notre Dame, IN, USA
| | - Arial Shogren
- Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI, USA
| | - Jay P Zarnetske
- Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI, USA
| | - Frances Iannucci
- Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT, USA
- Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - William B Bowden
- Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT, USA
| | - Samuel P Bratsman
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Leika Patch
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Rachel Watts
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Randy Fulweber
- Toolik GIS, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Rebecca J Frei
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | - Amanda M Huebner
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, USA
| | - Sarah M Ludwig
- Department of Earth and Environmental Science, Columbia University, NY, NY, USA
| | - Gregory T Carling
- Department of Geological Sciences, Brigham Young University, Provo, UT, USA
| | | |
Collapse
|
23
|
Zhi W, Feng D, Tsai WP, Sterle G, Harpold A, Shen C, Li L. From Hydrometeorology to River Water Quality: Can a Deep Learning Model Predict Dissolved Oxygen at the Continental Scale? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:2357-2368. [PMID: 33533608 DOI: 10.1021/acs.est.0c06783] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Dissolved oxygen (DO) reflects river metabolic pulses and is an essential water quality measure. Our capabilities of forecasting DO however remain elusive. Water quality data, specifically DO data here, often have large gaps and sparse areal and temporal coverage. Earth surface and hydrometeorology data, on the other hand, have become largely available. Here we ask: can a Long Short-Term Memory (LSTM) model learn about river DO dynamics from sparse DO and intensive (daily) hydrometeorology data? We used CAMELS-chem, a new data set with DO concentrations from 236 minimally disturbed watersheds across the U.S. The model generally learns the theory of DO solubility and captures its decreasing trend with increasing water temperature. It exhibits the potential of predicting DO in "chemically ungauged basins", defined as basins without any measurements of DO and broadly water quality in general. The model however misses some DO peaks and troughs when in-stream biogeochemical processes become important. Surprisingly, the model does not perform better where more data are available. Instead, it performs better in basins with low variations of streamflow and DO, high runoff-ratio (>0.45), and winter precipitation peaks. Results here suggest that more data collections at DO peaks and troughs and in sparsely monitored areas are essential to overcome the issue of data scarcity, an outstanding challenge in the water quality community.
Collapse
Affiliation(s)
- Wei Zhi
- Department of Civil and Environmental Engineering, The Pennsylvania State University, State College, Pennsylvania 16802, United States
| | - Dapeng Feng
- Department of Civil and Environmental Engineering, The Pennsylvania State University, State College, Pennsylvania 16802, United States
| | - Wen-Ping Tsai
- Department of Civil and Environmental Engineering, The Pennsylvania State University, State College, Pennsylvania 16802, United States
| | - Gary Sterle
- Department of Natural Resources & Environmental Science, The University of Nevada, Reno, Nevada 89557, United States
| | - Adrian Harpold
- Department of Natural Resources & Environmental Science, The University of Nevada, Reno, Nevada 89557, United States
| | - Chaopeng Shen
- Department of Civil and Environmental Engineering, The Pennsylvania State University, State College, Pennsylvania 16802, United States
| | - Li Li
- Department of Civil and Environmental Engineering, The Pennsylvania State University, State College, Pennsylvania 16802, United States
| |
Collapse
|
24
|
Wologo E, Shakil S, Zolkos S, Textor S, Ewing S, Klassen J, Spencer RGM, Podgorski DC, Tank SE, Baker MA, O'Donnell JA, Wickland KP, Foks SSW, Zarnetske JP, Lee‐Cullin J, Liu F, Yang Y, Kortelainen P, Kolehmainen J, Dean JF, Vonk JE, Holmes RM, Pinay G, Powell MM, Howe J, Frei RJ, Bratsman SP, Abbott BW. Stream Dissolved Organic Matter in Permafrost Regions Shows Surprising Compositional Similarities but Negative Priming and Nutrient Effects. GLOBAL BIOGEOCHEMICAL CYCLES 2021; 35:e2020GB006719. [PMID: 33519064 PMCID: PMC7816262 DOI: 10.1029/2020gb006719] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/05/2020] [Accepted: 09/22/2020] [Indexed: 05/04/2023]
Abstract
Permafrost degradation is delivering bioavailable dissolved organic matter (DOM) and inorganic nutrients to surface water networks. While these permafrost subsidies represent a small portion of total fluvial DOM and nutrient fluxes, they could influence food webs and net ecosystem carbon balance via priming or nutrient effects that destabilize background DOM. We investigated how addition of biolabile carbon (acetate) and inorganic nutrients (nitrogen and phosphorus) affected DOM decomposition with 28-day incubations. We incubated late-summer stream water from 23 locations nested in seven northern or high-altitude regions in Asia, Europe, and North America. DOM loss ranged from 3% to 52%, showing a variety of longitudinal patterns within stream networks. DOM optical properties varied widely, but DOM showed compositional similarity based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. Addition of acetate and nutrients decreased bulk DOM mineralization (i.e., negative priming), with more negative effects on biodegradable DOM but neutral or positive effects on stable DOM. Unexpectedly, acetate and nutrients triggered breakdown of colored DOM (CDOM), with median decreases of 1.6% in the control and 22% in the amended treatment. Additionally, the uptake of added acetate was strongly limited by nutrient availability across sites. These findings suggest that biolabile DOM and nutrients released from degrading permafrost may decrease background DOM mineralization but alter stoichiometry and light conditions in receiving waterbodies. We conclude that priming and nutrient effects are coupled in northern aquatic ecosystems and that quantifying two-way interactions between DOM properties and environmental conditions could resolve conflicting observations about the drivers of DOM in permafrost zone waterways.
Collapse
Affiliation(s)
- Ethan Wologo
- Department of Land Resources and Environmental SciencesMontana State UniversityBozemanMTUSA
| | - Sarah Shakil
- Department of Biological SciencesUniversity of AlbertaEdmontonAlbertaCanada
| | - Scott Zolkos
- Department of Biological SciencesUniversity of AlbertaEdmontonAlbertaCanada
- Woods Hole Research CenterWoods HoleMAUSA
| | - Sadie Textor
- Department of Earth, Ocean and Atmospheric Science and National High Magnetic Field Laboratory Geochemistry GroupFlorida State UniversityTallahasseeFLUSA
| | - Stephanie Ewing
- Department of Land Resources and Environmental SciencesMontana State UniversityBozemanMTUSA
| | - Jane Klassen
- Department of Land Resources and Environmental SciencesMontana State UniversityBozemanMTUSA
| | - Robert G. M. Spencer
- Department of Earth, Ocean and Atmospheric Science and National High Magnetic Field Laboratory Geochemistry GroupFlorida State UniversityTallahasseeFLUSA
| | - David C. Podgorski
- Department of Earth, Ocean and Atmospheric Science and National High Magnetic Field Laboratory Geochemistry GroupFlorida State UniversityTallahasseeFLUSA
| | - Suzanne E. Tank
- Department of Biological SciencesUniversity of AlbertaEdmontonAlbertaCanada
| | - Michelle A. Baker
- Department of Biology and Ecology CenterUtah State UniversityLoganUTUSA
| | | | | | | | - Jay P. Zarnetske
- Department of Earth and Environmental SciencesMichigan State UniversityEast LansingMIUSA
| | - Joseph Lee‐Cullin
- Department of Earth and Environmental SciencesMichigan State UniversityEast LansingMIUSA
| | - Futing Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of BotanyChinese Academy of SciencesBeijingChina
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of BotanyChinese Academy of SciencesBeijingChina
| | | | | | - Joshua F. Dean
- Department of Earth SciencesVrije Universiteit AmsterdamAmsterdamNetherlands
- School of Environmental SciencesUniversity of LiverpoolLiverpoolUK
| | - Jorien E. Vonk
- Department of Earth SciencesVrije Universiteit AmsterdamAmsterdamNetherlands
| | | | - Gilles Pinay
- Environnement‐Ville‐Société (UMR5600) ‐ Centre National de la Recherche Scientifique (CNRS)LyonFrance
| | - Michaela M. Powell
- Department of Land Resources and Environmental SciencesMontana State UniversityBozemanMTUSA
| | - Jansen Howe
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUTUSA
| | - Rebecca J. Frei
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUTUSA
- Department of Renewable ResourcesUniversity of AlbertaEdmontonAlbertaCanada
| | - Samuel P. Bratsman
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUTUSA
| | - Benjamin W. Abbott
- Department of Plant and Wildlife SciencesBrigham Young UniversityProvoUTUSA
| |
Collapse
|
25
|
Zhi W, Li L. The Shallow and Deep Hypothesis: Subsurface Vertical Chemical Contrasts Shape Nitrate Export Patterns from Different Land Uses. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11915-11928. [PMID: 32812426 DOI: 10.1021/acs.est.0c01340] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Eutrophication has threatened water resources worldwide, yet mechanistic understanding on controls of nutrient export remains elusive. This work tests the shallow and deep hypothesis: subsurface vertical chemical contrasts regulate nitrate export patterns under different land use conditions. We synthesized data from 228 watersheds and used reactive transport modeling (500 simulations) under broad land use, climate, and geology conditions. Data synthesis indicated that human perturbation has amplified chemical contrasts in shallow water (e.g., soil water) versus deep waters (e.g., groundwater), inducing primarily flushing patterns (concentrations increase with streamflow) in agriculture lands and dilution patterns (concentrations decrease with streamflow) in urban watersheds. Results revealed a quantitative relationship between export patterns and shallow-versus-deep concentration contrasts, underscoring the often-overlooked role of nutrient distribution over depth. Results challenge the commonly held perception that legacy stores in agricultural lands induce chemostasis where concentrations vary negligibly with streamflow. They suggest that nitrate concentrations from agricultural lands will escalate during large hydrological events, which can exacerbate nutrient export problems as flooding events intensify in the future climate.
Collapse
Affiliation(s)
- Wei Zhi
- Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Li Li
- Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| |
Collapse
|
26
|
Weller DE, Jordan TE. Inexpensive spot sampling provides unexpectedly effective indicators of watershed nitrogen status. Ecosphere 2020. [DOI: 10.1002/ecs2.3224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Donald E. Weller
- Smithsonian Environmental Research Center 647 Contees Wharf Road Edgewater Maryland21037‐3702USA
| | - Thomas E. Jordan
- Smithsonian Environmental Research Center 647 Contees Wharf Road Edgewater Maryland21037‐3702USA
| |
Collapse
|
27
|
Source Switching Maintains Dissolved Organic Matter Chemostasis Across Discharge Levels in a Large Temperate River Network. Ecosystems 2020. [DOI: 10.1007/s10021-020-00514-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
28
|
Mansfeldt C, Deiner K, Mächler E, Fenner K, Eggen RIL, Stamm C, Schönenberger U, Walser JC, Altermatt F. Microbial community shifts in streams receiving treated wastewater effluent. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 709:135727. [PMID: 31887504 DOI: 10.1016/j.scitotenv.2019.135727] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/22/2019] [Accepted: 11/22/2019] [Indexed: 05/17/2023]
Abstract
Wastewater treatment plant (WWTP) effluents release not only chemical constituents in watersheds, but also contain microorganisms. Thus, an understanding of what microorganisms are released and how they change microbial communities within natural streams is needed. To characterize the community shifts in streams receiving WWTP effluent, we sampled water-column microorganisms from upstream, downstream, and the effluent of WWTPs located on 23 headwater streams in which no other effluent was released upstream. We characterized the bacterial community by sequencing the V3-V4 region of the 16S rRNA gene. We hypothesized that the downstream community profile would be a hydraulic mixture between the two sources (i.e., upstream and effluent). In ordination analyses, the downstream bacterial community profile was a mixture between the upstream and effluent. For 14 of the sites, the main contribution (>50%) to the downstream community originated from bacteria in the WWTP effluent and significant shifts in relative abundance of specific sequence variants were detected. These shifts in sequence variants may serve as general bioindicators of wastewater-effluent influenced streams, with a human-gut related Ruminococcus genus displaying the highest shift (30-fold higher abundances downstream). However, not all taxa composition changes were predicted based on hydraulic mixing alone. Specifically, the decrease of Cyanobacteria/Chloroplast reads was not adequately described by hydraulic mixing. The potential alteration of stream microbial communities via a high inflow of human-gut related bacteria and a decrease in autotrophic functional groups resulting from WWTP effluent creates the potential for general shifts in stream ecosystem function.
Collapse
Affiliation(s)
- Cresten Mansfeldt
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Kristy Deiner
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Natural History Museum London, London, UK.
| | - Elvira Mächler
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zürich, Switzerland
| | - Kathrin Fenner
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland; Chemistry Department, University of Zürich, Zürich, Switzerland
| | - Rik I L Eggen
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland
| | - Christian Stamm
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Urs Schönenberger
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | | | - Florian Altermatt
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zürich, Switzerland
| |
Collapse
|
29
|
Combining Tools from Edge-of-Field to In-Stream to Attenuate Reactive Nitrogen along Small Agricultural Waterways. WATER 2020. [DOI: 10.3390/w12020383] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reducing excessive reactive nitrogen (N) in agricultural waterways is a major challenge for freshwater managers and landowners. Effective solutions require the use of multiple and combined N attenuation tools, targeted along small ditches and streams. We present a visual framework to guide novel applications of ‘tool stacking’ that include edge-of-field and waterway-based options targeting N delivery pathways, timing, and impacts in the receiving environment (i.e., changes in concentration or load). Implementing tools at multiple locations and scales using a ‘toolbox’ approach will better leverage key hydrological and biogeochemical processes for N attenuation (e.g., water retention, infiltration and filtering, contact with organic soils and microbes, and denitrification), in addition to enhancing ecological benefits to waterways. Our framework applies primarily to temperate or warmer climates, since cold temperatures and freeze–thaw-related processes limit biologically mediated N attenuation in cold climates. Moreover, we encourage scientists and managers to codevelop N attenuation toolboxes with farmers, since implementation will require tailored fits to local hydrological, social, and productive landscapes. Generating further knowledge around N attenuation tool stacking in different climates and landscape contexts will advance management actions to attenuate agricultural catchment N. Understanding how different tools can be best combined to target key contaminant transport pathways and create activated zones of attenuation along and within small agricultural waterways will be essential.
Collapse
|
30
|
Moatar F, Floury M, Gold AJ, Meybeck M, Renard B, Ferréol M, Chandesris A, Minaudo C, Addy K, Piffady J, Pinay G. Stream Solutes and Particulates Export Regimes: A New Framework to Optimize Their Monitoring. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2019.00516] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
|
31
|
Palmer M, Ruhi A. Linkages between flow regime, biota, and ecosystem processes: Implications for river restoration. Science 2019; 365:365/6459/eaaw2087. [DOI: 10.1126/science.aaw2087] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
River ecosystems are highly biodiverse, influence global biogeochemical cycles, and provide valued services. However, humans are increasingly degrading fluvial ecosystems by altering their streamflows. Effective river restoration requires advancing our mechanistic understanding of how flow regimes affect biota and ecosystem processes. Here, we review emerging advances in hydroecology relevant to this goal. Spatiotemporal variation in flow exerts direct and indirect control on the composition, structure, and dynamics of communities at local to regional scales. Streamflows also influence ecosystem processes, such as nutrient uptake and transformation, organic matter processing, and ecosystem metabolism. We are deepening our understanding of how biological processes, not just static patterns, affect and are affected by stream ecosystem processes. However, research on this nexus of flow-biota-ecosystem processes is at an early stage. We illustrate this frontier with evidence from highly altered regulated rivers and urban streams. We also identify research challenges that should be prioritized to advance process-based river restoration.
Collapse
|
32
|
Shogren AJ, Zarnetske JP, Abbott BW, Iannucci F, Frei RJ, Griffin NA, Bowden WB. Revealing biogeochemical signatures of Arctic landscapes with river chemistry. Sci Rep 2019; 9:12894. [PMID: 31501454 PMCID: PMC6733942 DOI: 10.1038/s41598-019-49296-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/20/2019] [Indexed: 12/14/2022] Open
Abstract
Riverine fluxes of carbon and inorganic nutrients are increasing in virtually all large permafrost-affected rivers, indicating major shifts in Arctic landscapes. However, it is currently difficult to identify what is causing these changes in nutrient processing and flux because most long-term records of Arctic river chemistry are from small, headwater catchments draining <200 km2 or from large rivers draining >100,000 km2. The interactions of nutrient sources and sinks across these scales are what ultimately control solute flux to the Arctic Ocean. In this context, we performed spatially-distributed sampling of 120 subcatchments nested within three Arctic watersheds spanning alpine, tundra, and glacial-lake landscapes in Alaska. We found that the dominant spatial scales controlling organic carbon and major nutrient concentrations was 3-30 km2, indicating a continuum of diffuse and discrete sourcing and processing dynamics. These patterns were consistent seasonally, suggesting that relatively fine-scale landscape patches drive solute generation in this region of the Arctic. These network-scale empirical frameworks could guide and benchmark future Earth system models seeking to represent lateral and longitudinal solute transport in rapidly changing Arctic landscapes.
Collapse
Affiliation(s)
- Arial J Shogren
- Michigan State University, Department of Earth and Environmental Sciences, East Lansing, Michigan, 48824, USA.
| | - Jay P Zarnetske
- Michigan State University, Department of Earth and Environmental Sciences, East Lansing, Michigan, 48824, USA
| | - Benjamin W Abbott
- Brigham Young University, Department of Plant and Wildlife Sciences, Provo, Utah, 84602, USA
| | - Frances Iannucci
- University of Vermont, Rubenstein School of Environment and Natural Resources, Burlington, Vermont, 05405, USA
| | - Rebecca J Frei
- Brigham Young University, Department of Plant and Wildlife Sciences, Provo, Utah, 84602, USA
- University of Alberta, Department of Renewable Resources, Edmonton, Alberta, T6G 2R3, Canada
| | - Natasha A Griffin
- Brigham Young University, Department of Plant and Wildlife Sciences, Provo, Utah, 84602, USA
| | - William B Bowden
- University of Vermont, Rubenstein School of Environment and Natural Resources, Burlington, Vermont, 05405, USA
| |
Collapse
|
33
|
Bieroza M, Bergström L, Ulén B, Djodjic F, Tonderski K, Heeb A, Svensson J, Malgeryd J. Hydrologic Extremes and Legacy Sources Can Override Efforts to Mitigate Nutrient and Sediment Losses at the Catchment Scale. JOURNAL OF ENVIRONMENTAL QUALITY 2019; 48:1314-1324. [PMID: 31589708 DOI: 10.2134/jeq2019.02.0063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Combating eutrophication requires changes in land and water management in agricultural catchments and implementation of mitigation measures to reduce phosphorus (P), nitrogen (N) and suspended sediment (SS) losses. To date, such mitigation measures have been built in many agricultural catchments, but there is a lack of studies evaluating their effectiveness. Here we evaluated the effectiveness of mitigation measures in a clay soil-dominated headwater catchment by combining the evaluation of long-term and high-frequency data with punctual measurements upstream and downstream of three mitigation measures: lime-filter drains, a two-stage ditch, and a sedimentation pond. Long-term hydrochemical data at the catchment outlet showed a significant decrease in P (-15%) and SS (-28%) and an increase in nitrate nitrogen (NO-N, +13%) concentrations. High-frequency (hourly) measurements with a wet-chemistry analyzer (total and reactive P) and optical sensor (NO-N and SS) showed that the catchment is an abundant source of nutrients and sediments and that their transport is exacerbated by prolonged drought and resuspension of stream sediments during storm events. Lime-filter drains showed a decrease in SS by 76% and total P by 80% and an increase in NO-N by 45% compared with traditional drains, potentially indicating pollution swapping. The effectiveness of two-stage ditch and sedimentation pond was less evident and depended on the prevalent hydrometeorological conditions that drove the resuspension of bed sediments and associated sediment-bound P transport. These results suggest that increased frequency of prolonged drought due to changing weather patterns and resuspension of SS and sediment-bound P during storm events can override the generally positive effect of mitigation measures.
Collapse
|
34
|
Bradley PM, Journey CA, Berninger JP, Button DT, Clark JM, Corsi SR, DeCicco LA, Hopkins KG, Huffman BJ, Nakagaki N, Norman JE, Nowell LH, Qi SL, VanMetre PC, Waite IR. Mixed-chemical exposure and predicted effects potential in wadeable southeastern USA streams. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 655:70-83. [PMID: 30469070 DOI: 10.1016/j.scitotenv.2018.11.186] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/12/2018] [Accepted: 11/12/2018] [Indexed: 05/19/2023]
Abstract
Complex chemical mixtures have been widely reported in larger streams but relatively little work has been done to characterize them and assess their potential effects in headwater streams. In 2014, the United States Geological Survey (USGS) sampled 54 Piedmont streams over ten weeks and measured 475 unique organic compounds using five analytical methods. Maximum and median exposure conditions were evaluated in relation to watershed characteristics and for potential biological effects using multiple lines of evidence. Results demonstrate that mixed-contaminant exposures are ubiquitous and varied in sampled headwater streams. Approximately 56% (264) of the 475 compounds were detected at least once across all sites. Cumulative maximum concentrations ranged 1,922-162,346ngL-1 per site. Chemical occurrence significantly correlated to urban land use but was not related to presence/absence of wastewater treatment facility discharges. Designed bioactive chemicals represent about 2/3rd of chemicals detected, notably pharmaceuticals and pesticides, qualitative evidence for possible adverse biological effects. Comparative Toxicogenomics Database chemical-gene associations applied to maximum exposure conditions indicate >12,000 and 2,900 potential gene targets were predicted at least once across all sites for fish and invertebrates, respectively. Analysis of cumulative exposure-activity ratios provided additional evidence that, at a minimum, transient exposures with high probability of molecular effects to vertebrates were common. Finally, cumulative detections and concentrations correlated inversely with invertebrate metrics from in-stream surveys. The results demonstrate widespread instream exposure to extensive contaminant mixtures and compelling multiple lines of evidence for adverse effects on aquatic communities.
Collapse
|
35
|
Harvey E, Altermatt F. Regulation of the functional structure of aquatic communities across spatial scales in a major river network. Ecology 2019; 100:e02633. [DOI: 10.1002/ecy.2633] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/07/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Eric Harvey
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH‐8057 Switzerland
- Eawag, Swiss Federal Institute of Aquatic Science and Technology Duebendorf CH‐8600 Switzerland
- Département de Sciences Biologiques Université de Montréal Montréal H2V 2S9 Canada
| | - Florian Altermatt
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH‐8057 Switzerland
- Eawag, Swiss Federal Institute of Aquatic Science and Technology Duebendorf CH‐8600 Switzerland
| |
Collapse
|
36
|
Johnson B, Smith E, Ackerman JW, Dye S, Polinsky R, Somerville E, Decker C, Little D, Pond G, D'Amico E. Spatial Convergence in Major Dissolved Ion Concentrations and Implications of Headwater Mining for Downstream Water Quality. JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION 2019; 55:247-258. [PMID: 33354106 PMCID: PMC7751627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Spatial patterns in major dissolved solute concentrations were examined to better understand impact of surface coal mining in headwaters on downstream water chemistry. Sixty sites were sampled seasonally from 2012 to 2014 in an eastern Kentucky watershed. Watershed areas (WA) ranged from 1.6 to 400.5 km2 and were mostly forested (58%-95%), but some drained as much as 31% surface mining. Measures of total dissolved solutes and most component ions were positively correlated with mining. Analytes showed strong convergent spatial patterns with high variability in headwaters (<15 km2 WA) that stabilized downstream (WA > 75 km2), indicating hydrologic mixing primarily controls downstream values. Mean headwater solute concentrations were a good predictor of downstream values, with % differences ranging from 0.55% (Na+) to 28.78% (Mg2+). In a mined scenario where all headwaters had impacts, downstream solute concentrations roughly doubled. Alternatively, if mining impacts to headwaters were minimized, downstream solute concentrations better approximated the 300 μS/cm conductivity criterion deemed protective of aquatic life. Temporal variability also had convergent spatial patterns and mined streams were less variable due to unnaturally stable hydrology. The highly conserved nature of dissolved solutes from mining activities and lack of viable treatment options suggest forested, unmined watersheds would provide dilution that would be protective of downstream aquatic life.
Collapse
Affiliation(s)
- Brent Johnson
- United States Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Cincinnati, OH, USA
| | - Elizabeth Smith
- United States Environmental Protection Agency, Region 4, Water Protection Division, Atlanta, GA, USA
| | - Jerry W Ackerman
- United States Environmental Protection Agency, Region 4, Science and Ecosystem Support Division, Athens, GA, USA
| | - Sue Dye
- United States Environmental Protection Agency, Region 4, Science and Ecosystem Support Division, Athens, GA, USA
| | - Robyn Polinsky
- United States Environmental Protection Agency, Region 4, Water Protection Division, Atlanta, GA, USA
| | - Eric Somerville
- United States Environmental Protection Agency, Region 4, Water Protection Division, Atlanta, GA, USA
| | - Chris Decker
- United States Environmental Protection Agency, Region 4, Water Protection Division, Atlanta, GA, USA
| | - Derek Little
- United States Environmental Protection Agency, Region 4, Science and Ecosystem Support Division, Athens, GA, USA
| | - Gregory Pond
- United States Environmental Protection Agency, EPA Gulf of Mexico Program, Gulfport MS, USA
| | - Ellen D'Amico
- GIS Support specialist, Pegasus Technical Services Inc., Cincinnati, OH, USA
| |
Collapse
|
37
|
Abstract
Although groundwater is a critical source of drinking water and irrigation, it has been polluted worldwide by agriculture, industry, and domestic activity. Because assessing groundwater quality and recovery rates is challenging, we developed a method for determining where and how quickly nitrate is removed in aquifers using just a few point measurements of groundwater chemistry. This methodology opens new avenues for characterizing catchment-scale nutrient dynamics, including nitrogen, carbon, and silica, with existing datasets for ecosystems around the globe. Understanding the subsurface structure of reactivity would also improve estimates of recovery time frames for polluted ecosystems and inform sustainable limits for anthropogenic activity. Biogeochemical reactions occur unevenly in space and time, but this heterogeneity is often simplified as a linear average due to sparse data, especially in subsurface environments where access is limited. For example, little is known about the spatial variability of groundwater denitrification, an important process in removing nitrate originating from agriculture and land use conversion. Information about the rate, arrangement, and extent of denitrification is needed to determine sustainable limits of human activity and to predict recovery time frames. Here, we developed and validated a method for inferring the spatial organization of sequential biogeochemical reactions in an aquifer in France. We applied it to five other aquifers in different geological settings located in the United States and compared results among 44 locations across the six aquifers to assess the generality of reactivity trends. Of the sampling locations, 79% showed pronounced increases of reactivity with depth. This suggests that previous estimates of denitrification have underestimated the capacity of deep aquifers to remove nitrate, while overestimating nitrate removal in shallow flow paths. Oxygen and nitrate reduction likely increases with depth because there is relatively little organic carbon in agricultural soils and because excess nitrate input has depleted solid phase electron donors near the surface. Our findings explain the long-standing conundrum of why apparent reaction rates of oxygen in aquifers are typically smaller than those of nitrate, which is energetically less favorable. This stratified reactivity framework is promising for mapping vertical reactivity trends in aquifers, generating new understanding of subsurface ecosystems and their capacity to remove contaminants.
Collapse
|
38
|
Bieroza MZ, Heathwaite AL, Bechmann M, Kyllmar K, Jordan P. The concentration-discharge slope as a tool for water quality management. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 630:738-749. [PMID: 29499532 DOI: 10.1016/j.scitotenv.2018.02.256] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/20/2018] [Accepted: 02/21/2018] [Indexed: 05/23/2023]
Abstract
Recent technological breakthroughs of optical sensors and analysers have enabled matching the water quality measurement interval to the time scales of stream flow changes and led to an improved understanding of spatially and temporally heterogeneous sources and delivery pathways for many solutes and particulates. This new ability to match the chemograph with the hydrograph has promoted renewed interest in the concentration-discharge (c-q) relationship and its value in characterizing catchment storage, time lags and legacy effects for both weathering products and anthropogenic pollutants. In this paper we evaluated the stream c-q relationships for a number of water quality determinands (phosphorus, suspended sediments, nitrogen) in intensively managed agricultural catchments based on both high-frequency (sub-hourly) and long-term low-frequency (fortnightly-monthly) routine monitoring data. We used resampled high-frequency data to test the uncertainty in water quality parameters (e.g. mean, 95th percentile and load) derived from low-frequency sub-datasets. We showed that the uncertainty in water quality parameters increases with reduced sampling frequency as a function of the c-q slope. We also showed that different sources and delivery pathways control c-q relationship for different solutes and particulates. Secondly, we evaluated the variation in c-q slopes derived from the long-term low-frequency data for different determinands and catchments and showed strong chemostatic behaviour for phosphorus and nitrogen due to saturation and agricultural legacy effects. The c-q slope analysis can provide an effective tool to evaluate the current monitoring networks and the effectiveness of water management interventions. This research highlights how improved understanding of solute and particulate dynamics obtained with optical sensors and analysers can be used to understand patterns in long-term water quality time series, reduce the uncertainty in the monitoring data and to manage eutrophication in agricultural catchments.
Collapse
Affiliation(s)
- M Z Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Box 7014, 750 07, Sweden.
| | - A L Heathwaite
- Lancaster Environment Centre, Library Avenue, Lancaster University, Lancaster LA1 4YQ, United Kingdom.
| | - M Bechmann
- Norwegian Institute of Bioeconomy Research, P.O. Box 115, NO-1431 Ås, Norway.
| | - K Kyllmar
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Box 7014, 750 07, Sweden.
| | - P Jordan
- School of Geography & Environmental Sciences, Ulster University, Coleraine BT52 1SA, United Kingdom.
| |
Collapse
|