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Li X, Chai B, Wang C, Li H, Wu Y, Lei X, Chen B. Spatial variation of dissolved organic matter in the Tuojiang River Basin in Chengdu, China: insights based on EEMs-PARAFAC analysis. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:1178-1193. [PMID: 37771221 PMCID: wst_2023_267 DOI: 10.2166/wst.2023.267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
Three-dimensional excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis was adopted to investigate the characteristics of dissolved organic matter (DOM) components in water samples collected from the Tuojiang River Basin in Chengdu, including its main stream and tributaries. Four DOM components that matched with three fluorescence peaks were identified in the whole river basin and tributaries; while three components corresponding to four fluorescence peaks were identified in the main stream. In all cases, humic-like components accounted for high proportions of the DOM. Correlation analysis revealed the same sources for four components in the whole river basin and its tributaries, whereas two components had different sources in the main stream. Ultraviolet absorbance parameters (SUVA254, SR) and fluorescence parameters (BIX, HIX, FI, β:α) indicated the dominant autochthonous sources of DOM in the whole river basin. Higher terrestrial inputs of DOM were observed in the tributaries than in the main stream. In the areas influenced by human activities (6#, 17#, 18#), the sources of DOM showed strong terrestrial characteristics and high degrees of humification and aromatization, as well as serious pollution. The results of this study have potentially far-reaching implications for environmental water management in the area.
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Affiliation(s)
- Xiaxia Li
- Collaborative Innovation Center for Intelligent Regulation & Comprehensive Management of Water Resources, College of Water Resources and Hydropower, Hebei University of Engineering, Handan 056038, China; Hebei Key Laboratory of Intelligent Water Conservancy, College of Water Conservancy and Hydropower, Hebei University of Engineering, Handan 056038, China E-mail:
| | - Beibei Chai
- Collaborative Innovation Center for Intelligent Regulation & Comprehensive Management of Water Resources, College of Water Resources and Hydropower, Hebei University of Engineering, Handan 056038, China; Hebei Key Laboratory of Intelligent Water Conservancy, College of Water Conservancy and Hydropower, Hebei University of Engineering, Handan 056038, China
| | - Chao Wang
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Hongtao Li
- Chengdu University of Technology, Chengdu 610059, China
| | - Yong Wu
- Chengdu University of Technology, Chengdu 610059, China
| | - Xiaohui Lei
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Bin Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China; Hebei Provincial Innovation Center for Water Pollution Control and Water Ecological Remediation, Hebei University of Engineering, Handan 056038, China
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Abstract
AbstractWatershed resilience is the ability of a watershed to maintain its characteristic system state while concurrently resisting, adapting to, and reorganizing after hydrological (for example, drought, flooding) or biogeochemical (for example, excessive nutrient) disturbances. Vulnerable waters include non-floodplain wetlands and headwater streams, abundant watershed components representing the most distal extent of the freshwater aquatic network. Vulnerable waters are hydrologically dynamic and biogeochemically reactive aquatic systems, storing, processing, and releasing water and entrained (that is, dissolved and particulate) materials along expanding and contracting aquatic networks. The hydrological and biogeochemical functions emerging from these processes affect the magnitude, frequency, timing, duration, storage, and rate of change of material and energy fluxes among watershed components and to downstream waters, thereby maintaining watershed states and imparting watershed resilience. We present here a conceptual framework for understanding how vulnerable waters confer watershed resilience. We demonstrate how individual and cumulative vulnerable-water modifications (for example, reduced extent, altered connectivity) affect watershed-scale hydrological and biogeochemical disturbance response and recovery, which decreases watershed resilience and can trigger transitions across thresholds to alternative watershed states (for example, states conducive to increased flood frequency or nutrient concentrations). We subsequently describe how resilient watersheds require spatial heterogeneity and temporal variability in hydrological and biogeochemical interactions between terrestrial systems and down-gradient waters, which necessitates attention to the conservation and restoration of vulnerable waters and their downstream connectivity gradients. To conclude, we provide actionable principles for resilient watersheds and articulate research needs to further watershed resilience science and vulnerable-water management.
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Segatto PL, Battin TJ, Bertuzzo E. The Metabolic Regimes at the Scale of an Entire Stream Network Unveiled Through Sensor Data and Machine Learning. Ecosystems 2021; 24:1792-1809. [PMID: 34803482 PMCID: PMC8593893 DOI: 10.1007/s10021-021-00618-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/07/2021] [Indexed: 12/01/2022]
Abstract
Streams and rivers form dense networks that drain the terrestrial landscape and are relevant for biodiversity dynamics, ecosystem functioning, and transport and transformation of carbon. Yet, resolving in both space and time gross primary production (GPP), ecosystem respiration (ER) and net ecosystem production (NEP) at the scale of entire stream networks has been elusive so far. Here, combining Random Forest (RF) with time series of sensor data in 12 reach sites, we predicted annual regimes of GPP, ER, and NEP in 292 individual stream reaches and disclosed properties emerging from the network they form. We further predicted available light and thermal regimes for the entire network and expanded the library of stream metabolism predictors. We found that the annual network-scale metabolism was heterotrophic yet with a clear peak of autotrophy in spring. In agreement with the River Continuum Concept, small headwaters and larger downstream reaches contributed 16% and 60%, respectively, to the annual network-scale GPP. Our results suggest that ER rather than GPP drives the metabolic stability at the network scale, which is likely attributable to the buffering function of the streambed for ER, while GPP is more susceptible to flow-induced disturbance and fluctuations in light availability. Furthermore, we found large terrestrial subsidies fueling ER, pointing to an unexpectedly high network-scale level of heterotrophy, otherwise masked by simply considering reach-scale NEP estimations. Our machine learning approach sheds new light on the spatiotemporal dynamics of ecosystem metabolism at the network scale, which is a prerequisite to integrate aquatic and terrestrial carbon cycling at relevant scales.
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Affiliation(s)
- Pier Luigi Segatto
- Stream Biofilm and Ecosystem Research Laboratory, Ecole Polytechinque Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Tom J Battin
- Stream Biofilm and Ecosystem Research Laboratory, Ecole Polytechinque Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Enrico Bertuzzo
- Department of Environmental Sciences, Informatics and Statistics, University of Venice Ca' Foscari, 30170 Venice, Italy
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Retelletti Brogi S, Balestra C, Casotti R, Cossarini G, Galletti Y, Gonnelli M, Vestri S, Santinelli C. Time resolved data unveils the complex DOM dynamics in a Mediterranean river. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 733:139212. [PMID: 32446062 DOI: 10.1016/j.scitotenv.2020.139212] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/02/2020] [Accepted: 05/02/2020] [Indexed: 06/11/2023]
Abstract
In this study, dissolved organic carbon (DOC) data and optical properties (absorbance and fluorescence) of DOM, weekly collected in the Arno River for 2 years, are used to investigate the main processes determining DOM temporal dynamics in a small Mediterranean river, with torrential hydrology and medium-high human impact, and to quantify the contribution of this river to Med Sea carbon budget. A clear seasonal cycle of DOM, with DOC values ranging between 170 and 490 μM, was observed. Optical properties indicates that DOM quality in the river is different depending on the season; terrestrial humic-like substances prevail in winter, when discharge and floods are the main drivers of DOM concentration and quality, whereas autochthonous protein-like substances prevail in spring and summer, when biological processes dominate. Our results provide a robust estimate of the DOC flux to the Med Sea (9.6 · 109 g DOC yr-1) and of its range of variability (12.95 · 109-5.12 · 109 g DOC yr-1). The 80% of this flux was generally delivered during autumn/winter with significant amounts ascribed to single flood events (up to 26% in 2014). This study, by providing a rich dataset on water quantity and quality and by quantifying the importance of the hydrological regime on DOC transport, represents an important step toward a quantitative modeling of the Arno River.
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Affiliation(s)
| | - Cecilia Balestra
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples 80121, Italy
| | | | - Gianpiero Cossarini
- Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/C, 34010 Sgonico, (TS), Italy
| | - Yuri Galletti
- Istituto di Biofisica, CNR, Via G. Moruzzi, Pisa 56124, Italy
| | | | - Stefano Vestri
- Istituto di Biofisica, CNR, Via G. Moruzzi, Pisa 56124, Italy
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5
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Dong X, Fisher SG. Ecosystem spatial self-organization: Free order for nothing? ECOLOGICAL COMPLEXITY 2019. [DOI: 10.1016/j.ecocom.2019.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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6
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7
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Hasselquist EM, Lidberg W, Sponseller RA, Ågren A, Laudon H. Identifying and assessing the potential hydrological function of past artificial forest drainage. AMBIO 2018; 47:546-556. [PMID: 29098602 PMCID: PMC6072640 DOI: 10.1007/s13280-017-0984-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/06/2017] [Accepted: 10/12/2017] [Indexed: 05/29/2023]
Abstract
Drainage of forested wetlands for increased timber production has profoundly altered the hydrology and water quality of their downstream waterways. Some ditches need network maintenance (DNM), but potential positive effects on tree productivity must be balanced against environmental impacts. Currently, no clear guidelines exist for DNM that strike this balance. Our study helps begin to prioritise DNM by: (1) quantifying ditches by soil type in the 68 km2 Krycklan Catchment Study in northern Sweden and (2) using upslope catchment area algorithms on new high-resolution digital elevation models to determine their likelihood to drain water. Ditches nearly doubled the size of the stream network (178-327 km) and 17% of ditches occurred on well-draining sedimentary soils, presumably making DNM unwarranted. Modelling results suggest that 25-50% of ditches may never support flow. With new laser scanning technology, simple mapping and modelling methods can locate ditches and model their function, facilitating efforts to balance DNM with environmental impacts.
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Affiliation(s)
- Eliza Maher Hasselquist
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd, 901 83 Umeå, Sweden
| | - William Lidberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd, 901 83 Umeå, Sweden
| | - Ryan A. Sponseller
- Department of Ecology and Environmental Science, Umeå University, 901 87 Umeå, Sweden
| | - Anneli Ågren
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd, 901 83 Umeå, Sweden
| | - Hjalmar Laudon
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd, 901 83 Umeå, Sweden
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8
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The freshwater landscape: lake, wetland, and stream abundance and connectivity at macroscales. Ecosphere 2017. [DOI: 10.1002/ecs2.1911] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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9
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Pettit NE, Naiman RJ, Warfe DM, Jardine TD, Douglas MM, Bunn SE, Davies PM. Productivity and Connectivity in Tropical Riverscapes of Northern Australia: Ecological Insights for Management. Ecosystems 2016. [DOI: 10.1007/s10021-016-0037-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Butturini A, Guarch A, Romaní AM, Freixa A, Amalfitano S, Fazi S, Ejarque E. Hydrological conditions control in situ DOM retention and release along a Mediterranean river. WATER RESEARCH 2016; 99:33-45. [PMID: 27132197 DOI: 10.1016/j.watres.2016.04.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 04/14/2016] [Accepted: 04/15/2016] [Indexed: 06/05/2023]
Abstract
Uncertainties exist regarding the magnitude of in situ dissolved organic matter (DOM) processing in lotic systems. In addition, little is known about the effects of extreme hydrological events on in-stream DOM retention or release during downriver transport. This study quantified the net in-stream retention/release efficiencies (η) of dissolved organic carbon (DOC) and its humic and protein-like fluorescent fractions along a Mediterranean river during drought, baseflow and flood conditions. High performance size exclusion chromatography was used to describe the apparent size distributions of the humic and protein-like DOM moieties. A snapshot mass balance allowed estimating the η values of DOC and humic and protein-like fractions. Significant DOM net retention (η < 0) was detected during the drought condition and the protein-like fraction was more retained than the humic-like fraction and bulk DOC. In addition, small substances were more efficiently retained than larger substances. DOC retention decreased under baseflow conditions, but it remained significant. The humic and protein-like net efficiencies exhibited high variability, but the net retention were not significant. From a longitudinal perspective, the entire fluvial corridor contributed net retention of DOC and humic and protein-like moieties net retention during drought condition. In contrast, net retention/release efficiencies exhibited spatial variability during baseflow condition. The flood preferentially mobilized large size DOM molecules and the fluvial corridor behaved as a homogeneous passive DOM (η = 0) conduit. This research highlights the relevance of hydrological extreme events on the magnitude of DOM retention/release mass balance and emphasizes the need to perform measurements during these conditions to quantify the impact of fluvial corridors on DOM fate and transport.
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Affiliation(s)
- A Butturini
- Departament d'Ecologia, Universitat de Barcelona, Barcelona, Spain.
| | - A Guarch
- Departament d'Ecologia, Universitat de Barcelona, Barcelona, Spain
| | - A M Romaní
- Institute of Aquatic Ecology, Department of Environmental Sciences, University of Girona, Girona, Spain
| | - A Freixa
- Institute of Aquatic Ecology, Department of Environmental Sciences, University of Girona, Girona, Spain
| | - S Amalfitano
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Monterotondo, Roma, Italy
| | - S Fazi
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Monterotondo, Roma, Italy
| | - E Ejarque
- WasserCluster Lunz, Biologische Station GmbH, Lunz am See, Austria; Department of Limnology and Bio-Oceanography, University of Vienna, Austria
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11
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Cohen MJ, Creed IF, Alexander L, Basu NB, Calhoun AJK, Craft C, D'Amico E, DeKeyser E, Fowler L, Golden HE, Jawitz JW, Kalla P, Kirkman LK, Lane CR, Lang M, Leibowitz SG, Lewis DB, Marton J, McLaughlin DL, Mushet DM, Raanan-Kiperwas H, Rains MC, Smith L, Walls SC. Do geographically isolated wetlands influence landscape functions? Proc Natl Acad Sci U S A 2016; 113:1978-86. [PMID: 26858425 PMCID: PMC4776504 DOI: 10.1073/pnas.1512650113] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bodies to create spatial and temporal heterogeneity in the timing, flow paths, and magnitude of network connectivity. These attributes signal a critical role for GIWs in sustaining a portfolio of landscape functions, but legal protections remain weak despite preferential loss from many landscapes. GIWs lack persistent surface water connections, but this condition does not imply the absence of hydrological, biogeochemical, and biological exchanges with nearby and downstream waters. Although hydrological and biogeochemical connectivity is often episodic or slow (e.g., via groundwater), hydrologic continuity and limited evaporative solute enrichment suggest both flow generation and solute and sediment retention. Similarly, whereas biological connectivity usually requires overland dispersal, numerous organisms, including many rare or threatened species, use both GIWs and downstream waters at different times or life stages, suggesting that GIWs are critical elements of landscape habitat mosaics. Indeed, weaker hydrologic connectivity with downstream waters and constrained biological connectivity with other landscape elements are precisely what enhances some GIW functions and enables others. Based on analysis of wetland geography and synthesis of wetland functions, we argue that sustaining landscape functions requires conserving the entire continuum of wetland connectivity, including GIWs.
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Affiliation(s)
- Matthew J Cohen
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL 32611;
| | - Irena F Creed
- Department of Biology, Western University, London, ON, Canada N6A 5B7
| | - Laurie Alexander
- National Center for Environmental Assessment, United States Environmental Protection Agency, Washington, DC 20460
| | - Nandita B Basu
- Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON, Canada N2L 3G1
| | - Aram J K Calhoun
- Department of Wildlife, Fisheries, and Conservation Biology, University of Maine, Orono, ME 04469
| | - Christopher Craft
- School of Public Health and Environmental Affairs, Indiana University, Bloomington, IN 47405
| | | | - Edward DeKeyser
- School of Natural Resource Sciences, North Dakota State University, Fargo, ND 58108-6050
| | - Laurie Fowler
- Odum School of Ecology, The University of Georgia, Athens, GA 30602
| | - Heather E Golden
- National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, OH 45268
| | - James W Jawitz
- Soil and Water Science Department, University of Florida, Gainesville, FL 32611
| | - Peter Kalla
- Region 4, United States Environmental Protection Agency, Athens, GA 30605
| | | | - Charles R Lane
- National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, OH 45268
| | - Megan Lang
- Department of Geographical Sciences, University of Maryland, College Park, MD 20742
| | - Scott G Leibowitz
- Western Ecology Division, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Corvallis, OR 97333
| | - David Bruce Lewis
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620
| | | | - Daniel L McLaughlin
- Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - David M Mushet
- Northern Prairie Wildlife Research Center, United States Geological Survey, Jamestown, ND 58401
| | - Hadas Raanan-Kiperwas
- Office of Wetlands, Oceans, and Watersheds, United States Environmental Protection Agency, Washington, DC 20460
| | - Mark C Rains
- School of Geosciences, University of South Florida, Tampa, FL 3362
| | - Lora Smith
- Joseph W. Jones Ecological Research Center, Newton, GA 39870
| | - Susan C Walls
- Wetland and Aquatic Research Center, United States Geological Survey, Gainesville, FL 32653
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12
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Laudon H, Kuglerová L, Sponseller RA, Futter M, Nordin A, Bishop K, Lundmark T, Egnell G, Ågren AM. The role of biogeochemical hotspots, landscape heterogeneity, and hydrological connectivity for minimizing forestry effects on water quality. AMBIO 2016; 45 Suppl 2:152-62. [PMID: 26744050 PMCID: PMC4705070 DOI: 10.1007/s13280-015-0751-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Protecting water quality in forested regions is increasingly important as pressures from land-use, long-range transport of air pollutants, and climate change intensify. Maintaining forest industry without jeopardizing sustainability of surface water quality therefore requires new tools and approaches. Here, we show how forest management can be optimized by incorporating landscape sensitivity and hydrological connectivity into a framework that promotes the protection of water quality. We discuss how this approach can be operationalized into a hydromapping tool to support forestry operations that minimize water quality impacts. We specifically focus on how hydromapping can be used to support three fundamental aspects of land management planning including how to (i) locate areas where different forestry practices can be conducted with minimal water quality impact; (ii) guide the off-road driving of forestry machines to minimize soil damage; and (iii) optimize the design of riparian buffer zones. While this work has a boreal perspective, these concepts and approaches have broad-scale applicability.
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Affiliation(s)
- Hjalmar Laudon
- Department of Forest Ecology and Management, SLU, Skogsmarksgränd, 901 83, Umeå, Sweden.
| | - Lenka Kuglerová
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, V6T 1Z4, Canada.
| | - Ryan A Sponseller
- Department of Ecology and Environmental Science, Umeå University, 901 87, Umeå, Sweden.
| | - Martyn Futter
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
| | - Annika Nordin
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, Sweden.
| | - Kevin Bishop
- Department of Earth Science, Uppsala University, 752 36, Uppsala, Sweden.
| | - Tomas Lundmark
- Department of Forest Ecology and Management, SLU, Skogsmarksgränd, 901 83, Umeå, Sweden.
| | - Gustaf Egnell
- Department of Forest Ecology and Management, SLU, Skogsmarksgränd, 901 83, Umeå, Sweden.
| | - Anneli M Ågren
- Department of Forest Ecology and Management, SLU, Skogsmarksgränd, 901 83, Umeå, Sweden.
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13
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Abstract
By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in an entire fifth-order stream network. These samples were analyzed for an exhaustive suite of chemical constituents. The fine grain and broad extent of this study design allowed us to quantify spatial patterns over a range of scales by using empirical semivariograms that explicitly incorporated network topology. Here, we show that spatial structure, as determined by the characteristic shape of the semivariograms, differed both among chemical constituents and by spatial relationship (flow-connected, flow-unconnected, or Euclidean). Spatial structure was apparent at either a single scale or at multiple nested scales, suggesting separate processes operating simultaneously within the stream network and surrounding terrestrial landscape. Expected patterns of spatial dependence for flow-connected relationships (e.g., increasing homogeneity with downstream distance) occurred for some chemical constituents (e.g., dissolved organic carbon, sulfate, and aluminum) but not for others (e.g., nitrate, sodium). By comparing semivariograms for the different chemical constituents and spatial relationships, we were able to separate effects on streamwater chemistry of (i) fine-scale versus broad-scale processes and (ii) in-stream processes versus landscape controls. These findings provide insight on the hierarchical scaling of local, longitudinal, and landscape processes that drive biogeochemical patterns in stream networks.
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14
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Kuglerová L, Jansson R, Ågren A, Laudon H, Malm-Renöfält B. Groundwater discharge creates hotspots of riparian plant species richness in a boreal forest stream network. Ecology 2014; 95:715-25. [DOI: 10.1890/13-0363.1] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Landscape Influences on Ecosystem Function: Local and Routing Control of Oxygen Dynamics in a Floodplain Aquifer. Ecosystems 2013. [DOI: 10.1007/s10021-013-9717-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Tatariw C, Chapman EL, Sponseller RA, Mortazavi B, Edmonds JW. Denitrification in a large river: consideration of geomorphic controls on microbial activity and community structure. Ecology 2013; 94:2249-62. [DOI: 10.1890/12-1765.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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17
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Peterson EE, Ver Hoef JM, Isaak DJ, Falke JA, Fortin MJ, Jordan CE, McNyset K, Monestiez P, Ruesch AS, Sengupta A, Som N, Steel EA, Theobald DM, Torgersen CE, Wenger SJ. Modelling dendritic ecological networks in space: an integrated network perspective. Ecol Lett 2013; 16:707-19. [DOI: 10.1111/ele.12084] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 10/31/2012] [Accepted: 01/14/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Erin E. Peterson
- CSIRO Division of Mathematics; Informatics and Statistics; Dutton Park; QLD; Australia
| | | | - Dan J. Isaak
- USDA Forest Service; Rocky Mountain Research Station; Boise; ID; USA
| | - Jeffrey A. Falke
- Department of Fisheries and Wildlife; Oregon State University; Corvallis; OR; USA
| | - Marie-Josée Fortin
- Department of Ecology & Evolutionary Biology; University of Toronto; Toronto; ON; Canada
| | - Chris E. Jordan
- NOAA/NMFS/NWFSC Conservation Biology Division; Seattle; WA; USA
| | - Kristina McNyset
- Department of Fisheries and Wildlife; Oregon State University; Corvallis; OR; USA
| | - Pascal Monestiez
- Inra, Unité Biostatistique et Processus Spatiaux; Avignon; France
| | - Aaron S. Ruesch
- School of Environmental and Forest Sciences; University of Washington; Seattle; WA; USA
| | - Aritra Sengupta
- Department of Statistics; The Ohio State University; Columbus; OH; USA
| | - Nicholas Som
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis; OR; USA
| | - E. Ashley Steel
- USDA Forest Service; Pacific Northwest Research Station; Seattle; WA; USA
| | - David M. Theobald
- Department of Fish; Wildlife & Conservation Biology; Colorado State University; Fort Collins; CO; USA
| | - Christian E. Torgersen
- U.S. Geological Survey; Forest and Rangeland Ecosystem Science Center; Cascadia Field Station; School of Environmental and Forest Sciences; University of Washington; Seattle; WA; USA
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18
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Sponseller RA, Heffernan JB, Fisher SG. On the multiple ecological roles of water in river networks. Ecosphere 2013. [DOI: 10.1890/es12-00225.1] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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19
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Trimmer M, Grey J, Heppell CM, Hildrew AG, Lansdown K, Stahl H, Yvon-Durocher G. River bed carbon and nitrogen cycling: state of play and some new directions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2012; 434:143-158. [PMID: 22682557 DOI: 10.1016/j.scitotenv.2011.10.074] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 09/30/2011] [Accepted: 10/21/2011] [Indexed: 06/01/2023]
Abstract
The significance of freshwaters as key players in the global budget of both carbon dioxide and methane has recently been highlighted. In particular, rivers clearly do not act simply as inert conduits merely piping carbon from catchment to coast, but, on the whole, their metabolic activity transforms a considerable fraction of the carbon that they convey. In addition, nitrogen is cycled, sometimes in tight unison with carbon, with appreciable amounts being 'denitrified' between catchment and coast. However, shortfalls in our knowledge about the significance of exchange and interaction between rivers and their catchments, particularly the significance of interactions mediated through hyporheic sediments, are still apparent. From humble beginnings of quantifying the consumption of oxygen by small samples of gravel, to an integrated measurement of reach scale transformations of carbon and nitrogen, our understanding of the cycling of these two macro elements in rivers has improved markedly in the past few decades. However, recent discoveries of novel metabolic pathways in both the nitrogen and carbon cycle across a spectrum of aquatic ecosystems, highlights the need for new directions and a truly multidisciplinary approach to quantifying the flux of carbon and nitrogen through rivers.
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Affiliation(s)
- Mark Trimmer
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK.
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Lawrence GB, Simonin HA, Baldigo BP, Roy KM, Capone SB. Changes in the chemistry of acidified Adirondack streams from the early 1980s to 2008. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:2750-2758. [PMID: 21741140 DOI: 10.1016/j.envpol.2011.05.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 05/11/2011] [Accepted: 05/15/2011] [Indexed: 05/27/2023]
Abstract
Lakes in the Adirondack region of New York have partially recovered in response to declining deposition, but information on stream recovery is limited. Here we report results of Adirondack stream monitoring from the early 1980s to 2008. Despite a 50% reduction in atmospheric deposition of sulfur, overall increases in pH of only 0.28 and ANC of 13 μeq L(-1) were observed in 12 streams over 23 years, although greater changes did occur in streams with lower initial ANC, as expected. In the North Tributary of Buck Creek with high dissolved organic carbon (DOC) concentrations, SO(4)(2-) concentrations decreased from 1999 to 2008 at a rate of 2.0 μmol L(-1) y(-1), whereas in the neighboring South Tributary with low DOC concentrations, the decrease was only 0.73 μmol L(-1) y(-1). Ca(2+) leaching decreased in the North Tributary due to the SO(4)(2-) decrease, but this was partially offset by an increase in Ca(2+) leaching from increased DOC concentrations.
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Affiliation(s)
- G B Lawrence
- US Geological Survey, New York Water Science Center, 425 Jordan Road, Troy, NY 12180, United States.
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Carbon Cycling in Floodplain Ecosystems: Out-Gassing and Photosynthesis Transmit Soil δ13C Gradient Through Stream Food Webs. Ecosystems 2011. [DOI: 10.1007/s10021-011-9430-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Iwata T, Urabe J, Mitsuhashi H. Effects of drainage-basin geomorphology on insectivorous bird abundance in temperate forests. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2010; 24:1278-1289. [PMID: 20337688 DOI: 10.1111/j.1523-1739.2010.01493.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage-basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage-basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed-scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape-based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation.
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Affiliation(s)
- Tomoya Iwata
- Faculty of Engineering, University of Yamanashi, Kofu 400-8511, Japan.
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Poole GC. Stream hydrogeomorphology as a physical science basis for advances in stream ecology. ACTA ACUST UNITED AC 2010. [DOI: 10.1899/08-070.1] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Geoffrey C. Poole
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, Montana 59717-3120 USA
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Global Within-Site Variance in Soil Solution Nitrogen and Hydraulic Conductivity Are Correlated with Clay Content. Ecosystems 2009. [DOI: 10.1007/s10021-009-9293-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Feris KP, Ramsey PW, Gibbons SM, Frazar C, Rillig MC, Moore JN, Gannon JE, Holben WE. Hyporheic microbial community development is a sensitive indicator of metal contamination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:6158-6163. [PMID: 19746707 DOI: 10.1021/es9005465] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Accurate natural resource damage assessment necessitates monitoring organisms or communities that respond most sensitively to contaminants. Observational studies have demonstrated a correlation between fluvial heavy metal deposition and hyporheic microbial community structure. To establish a causal relationship between sediment metal content and the structure of colonizing bacterial communities, we performed a controlled field experiment River sediments of 1.75-2.36 mm in diameter with five different contaminant concentrations were collected from an environmental metal contamination gradient. Sediments were sterilized and then recolonized by incubation in the hyporheic zone of an uncontaminated river (i.e., a common garden experiment was performed). A significant correlation between hyporheic microbial community structure and heavy metal contamination (R2 = 0.81) was observed. The abundance of two phylogenetic groups was highly correlated with the level of heavy metal contamination (Group I, R2 = 0.96; Group III, R2 = 0.96, most closely affiliated with the alpha- and gamma-proteobacteria, respectively). Microbial community structural responses were detected at metal concentrations an order of magnitude lower than those previously reported to impact benthic macroinvertebrate communities. We conclude that hyporheic microbial communities could offer the most sensitive method for assessing natural resource damage in lotic ecosystems in response to fluvial heavy metal deposition.
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Affiliation(s)
- Kevin P Feris
- Department of Biology, Boise State University, Boise, Idaho 83725, USA.
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Brookshire ENJ, Valett HM, Gerber S. Maintenance of terrestrial nutrient loss signatures during in-stream transport. Ecology 2009; 90:293-9. [DOI: 10.1890/08-0949.1] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Martí E, Riera JL, Sabater F. Effects of Wastewater Treatment Plants on Stream Nutrient Dynamics Under Water Scarcity Conditions. THE HANDBOOK OF ENVIRONMENTAL CHEMISTRY 2009. [DOI: 10.1007/698_2009_33] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Sponseller RA, Fisher SG. The influence of drainage networks on patterns of soil respiration in a desert catchment. Ecology 2008; 89:1089-100. [PMID: 18481533 DOI: 10.1890/06-1933.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Hydrologic flow and connectivity act as important determinants of ecological pattern and process in heterogeneous landscapes. Here we examine how the routing of water through the drainage network of an upper Sonoran Desert basin influences landscape patterns of soil respiration (SR) at both seasonal and event-based timescales. At seasonal timescales, SR varied up to 13-fold with downstream position in the drainage network, and annual estimates of CO2 efflux ranged from 185 g C x m(-2) x yr(-1) to 1190 g C x m(-2) x yr(-1) for sites arrayed along the same flow path. Spatial patterns of SR were unrelated to the carbon and water content of surface soils, but rather tracked changes in plant size and productivity, which in turn reflect downstream increases in groundwater availability. The relative importance of precipitation and temperature as drivers of SR also changed with landscape position, with the latter becoming more important in downstream locations. At the scale of individual precipitation events, SR increased up to 30-fold upon rewetting but typically returned to background levels within 24 h, even when soil moisture remained elevated. Unlike patterns observed at seasonal scales, event-based losses of CO2 varied across the landscape as a function of the organic-matter content in surface soils. Results from labile carbon amendments confirm that CO2 losses following precipitation pulses are initially constrained by substrate availability, not soil drying. By mediating spatial patterns of vegetation structure and soil resource availability, drainage networks represent an important physical template upon which belowground processes are organized in desert basins.
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Affiliation(s)
- Ryan A Sponseller
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA.
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Verhoeven JT, Soons MB, Janssen R, Omtzigt N. An Operational Landscape Unit approach for identifying key landscape connections in wetland restoration. J Appl Ecol 2008. [DOI: 10.1111/j.1365-2664.2008.01534.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Inter-annual, Annual, and Seasonal Variation of P and N Retention in a Perennial and an Intermittent Stream. Ecosystems 2008. [DOI: 10.1007/s10021-008-9150-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lewis DB, Grimm NB. Hierarchical regulation of nitrogen export from urban catchments: interactions of storms and landscapes. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2007; 17:2347-2364. [PMID: 18213974 DOI: 10.1890/06-0031.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In urban catchments of arid central Arizona, we investigate how the export of mineral and organic nitrogen (N) in storm runoff is regulated by interactions between local landscape characteristics and broader scale storm features. First, we test whether N export is more a function of (1) processes that affect N concentration in runoff or (2) the propensity of the catchment to convey rainfall as runoff. With data pooled across catchments, the mass of N in export (load) is determined by processes regulating runoff N concentration. There are exceptions when catchments are examined individually, where N load from some catchments is determined by the hydrologic responsiveness of the catchment. Second, we investigate the relationship between N export and catchment features. Loads per catchment area were greater from more impervious catchments, probably because impervious catchments held more N in a mobilizable phase and conveyed more rainfall as overland flow. Loads per area were lower from larger catchments, possibly owing to more N-retention hot spots in larger catchments. Catchments with the greatest N exports were those with commercial land use, and loads decreased as development became less prevalent or as residential replaced industrial land use. Third, we investigated how catchment features moderated direct responses of N export to storms. Export was less correlated with storm features in catchments that were larger, more pervious, and less industrial. Results support an "N build and flush" hypothesis, which purports that there is little biotic processing of N deposited to arid, urban surfaces with little organic matter. The rate and duration of deposition determine the size of the mobile N pool. Any amount of rainfall capable of generating overland flow would entrain nearly all mobilizable N and export it from the catchment. Nonetheless, these results suggest that, even with daunting seasonal and interannual variability in storm conditions, material export can be reduced by managing intrinsic catchment features.
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Affiliation(s)
- David Bruce Lewis
- Global Institute of Sustainability, Arizona State University, P.O. Box 873211, Tempe, Arizona 85287-3211, USA.
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32
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Nutrient Vectors and Riparian Processing: A Review with Special Reference to African Semiarid Savanna Ecosystems. Ecosystems 2007. [DOI: 10.1007/s10021-007-9092-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Uncertainty in Nutrient Spiraling: Sensitivity of Spiraling Indices to Small Errors in Measured Nutrient Concentration. Ecosystems 2007. [DOI: 10.1007/s10021-007-9031-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Campbell Grant EH, Lowe WH, Fagan WF. Living in the branches: population dynamics and ecological processes in dendritic networks. Ecol Lett 2007; 10:165-75. [PMID: 17257104 DOI: 10.1111/j.1461-0248.2006.01007.x] [Citation(s) in RCA: 255] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Spatial structure regulates and modifies processes at several levels of ecological organization (e.g. individual/genetic, population and community) and is thus a key component of complex systems, where knowledge at a small scale can be insufficient for understanding system behaviour at a larger scale. Recent syntheses outline potential applications of network theory to ecological systems, but do not address the implications of physical structure for network dynamics. There is a specific need to examine how dendritic habitat structure, such as that found in stream, hedgerow and cave networks, influences ecological processes. Although dendritic networks are one type of ecological network, they are distinguished by two fundamental characteristics: (1) both the branches and the nodes serve as habitat, and (2) the specific spatial arrangement and hierarchical organization of these elements interacts with a species' movement behaviour to alter patterns of population distribution and abundance, and community interactions. Here, we summarize existing theory relating to ecological dynamics in dendritic networks, review empirical studies examining the population- and community-level consequences of these networks, and suggest future research integrating spatial pattern and processes in dendritic systems.
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Affiliation(s)
- Evan H Campbell Grant
- USGS--Patuxent Wildlife Research Center, 12100 Beech Forest Road, Laurel, MD 20708, USA.
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O'Connor BL, Hondzo M, Dobraca D, LaPara TM, Finlay JC, Brezonik PL. Quantity-activity relationship of denitrifying bacteria and environmental scaling in streams of a forested watershed. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006jg000254] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ben L. O'Connor
- Saint Anthony Falls Laboratory; University of Minnesota-Twin Cities; Minneapolis Minnesota USA
| | - Miki Hondzo
- Saint Anthony Falls Laboratory; University of Minnesota-Twin Cities; Minneapolis Minnesota USA
| | - Dina Dobraca
- Department of Genetics, Cell Biology, and Development; University of Minnesota-Twin Cities; Minneapolis Minnesota USA
| | - Timothy M. LaPara
- Department of Civil Engineering; University of Minnesota-Twin Cities; Minneapolis Minnesota USA
| | - Jacques C. Finlay
- Department of Ecology, Evolution, and Behavior; University of Minnesota-Twin Cities; St. Paul Minnesota USA
| | - Patrick L. Brezonik
- Department of Civil Engineering; University of Minnesota-Twin Cities; Minneapolis Minnesota USA
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Affiliation(s)
- Scott H. Ensign
- Curriculum in Ecology; University of North Carolina at Chapel Hill; Morehead City North Carolina USA
| | - Martin W. Doyle
- Department of Geography; University of North Carolina at Chapel Hill; Chapel Hill North Carolina USA
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Hale RL, Groffman PM. Chloride effects on nitrogen dynamics in forested and suburban stream debris dams. JOURNAL OF ENVIRONMENTAL QUALITY 2006; 35:2425-32. [PMID: 17071914 DOI: 10.2134/jeq2006.0164] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Organic debris dams (accumulations of organic material) can function as "hotspots" of nitrogen (N) processing in streams. Suburban streams are often characterized by high flows that prevent the accumulation of organic debris and by elevated concentrations of solutes, especially nitrate (NO(3)(-)) and chloride (Cl(-)). In this study we (1) studied the effects of urbanization on the extent and characteristics of debris dams in large and small streams and (2) evaluated the effects of NO(3)(-) and Cl(-) on rates of N cycle processes in these debris dams. In some suburban streams debris dams were small and rare, but in others factors that reduce the effects of high stream flows fostered the maintenance of debris dams. Ambient denitrification enzyme activity (DEA) in these suburban and forested streams was positively correlated with stream NO(3)(-) concentrations. In laboratory microcosms, DEA in debris dam material from a forested reference stream was increased by NO(3)(-) additions. Chloride additions constrained the response of DEA to NO(3)(-) additions in material from the forested stream, but had no effect on DEA in material from streams with a history of high Cl(-) levels. Chloride additions changed the sign of net N mineralization from negative (consumption of inorganic N) to positive in debris dam material from the forested reference stream, but had no effect on net mineralization in material from streams with a history of exposure to Cl(-). Understanding the factors regulating the maintenance and N cycling activity of organic debris, and incorporating them into urban stream management plans could have important effects on N dynamics in suburban watersheds.
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Affiliation(s)
- Rebecca L Hale
- Hampshire College, 895 West St., Amherst, MA 01002-5001, USA
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38
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Anderson KE, Nisbet RM, Diehl S. Spatial scaling of consumer-resource interactions in advection-dominated systems. Am Nat 2006; 168:358-72. [PMID: 16947111 DOI: 10.1086/506916] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Accepted: 03/14/2006] [Indexed: 11/04/2022]
Abstract
Ecologists studying consumer-resource interactions in advection-dominated systems such as streams and rivers frequently seek to link the results of small-scale experiments with larger-scale patterns of distribution and abundance. Accomplishing this goal requires determining the characteristic scale, termed the response length, at which there is a shift from local dynamics dominated by advective dispersal to larger-scale dynamics dominated by births and deaths. Here, we model the dynamics of consumer-resource systems in a spatially variable, advective environment and show how consumer-resource interactions alter the response length relative to its single-species value. For one case involving a grazer that emigrates in response to high predator density, we quantify the changes using published data from small-scale experiments on aquatic invertebrates. Using Fourier analysis, we describe the responses of advection-dominated consumer-resource systems to spatially extended environmental variability in a way that involves explicit consideration of the response length. The patterns we derive for different consumer-resource systems exhibit important similarities in how component populations respond to spatial environmental variability affecting dispersal as opposed to demographic parameters.
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Affiliation(s)
- Kurt E Anderson
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106, USA.
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Poole GC, Stanford JA, Running SW, Frissell CA. Multiscale geomorphic drivers of groundwater flow paths: subsurface hydrologic dynamics and hyporheic habitat diversity. ACTA ACUST UNITED AC 2006. [DOI: 10.1899/0887-3593(2006)25[288:mgdogf]2.0.co;2] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Sponseller RA, Fisher SG. Drainage Size, Stream Intermittency, and Ecosystem Function in a Sonoran Desert Landscape. Ecosystems 2006. [DOI: 10.1007/s10021-005-0167-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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