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Cereghetti E, Bossart R, Bruder A, Krähenbühl A, Wolf F, Altermatt F. The year of a leaf: Tracking the fate of leaf litter and its nutrients during aquatic decomposition and consumption. Ecology 2025; 106:e4520. [PMID: 39835745 DOI: 10.1002/ecy.4520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 11/05/2024] [Indexed: 01/22/2025]
Abstract
Temperate streams are subsidized by inputs of leaf litter peaking in fall. Yet, stream communities decompose dead leaves and integrate their energy into the aquatic food web throughout the whole year. Most studies investigating stream decomposition largely overlook long-term trajectories, which must be understood for an appropriate temporal upscaling of ecosystem processes. Using mesocosms, we quantified changes in carbon, nitrogen, and phosphorus content of three leaf species during decomposition at weekly to multi-month intervals for up to a year; then, we tested how decomposition duration affected the subsequent consumption by a keystone amphipod macroinvertebrate. Over a year, nitrogen and phosphorus percentage increased across all leaf species, but only the recalcitrant species maintained initial levels of absolute nitrogen and phosphorus. Prolonged decomposition barely affected or impaired amphipod consumption of labile leaf species, whereas it enhanced feeding on the recalcitrant species. Overall, we demonstrate that recalcitrant leaves might serve as longer stored potential resources for when labile species have already been consumed and that their increasing palatability observed over multi-month intervals of sustained decomposition may stabilize fluctuations in the rates of leaf litter integration into aquatic food webs. This yearlong perspective highlights the relevancy of slow-decomposing leaves for aquatic detrital communities.
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Affiliation(s)
- Eva Cereghetti
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Raphaël Bossart
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Andreas Bruder
- Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland, Mendrisio, Switzerland
| | - Andrin Krähenbühl
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Franziska Wolf
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Florian Altermatt
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
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2
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Robbins CJ, Manning DWP, Halvorson HM, Norman BC, Eckert RA, Pastor A, Dodd AK, Jabiol J, Bastias E, Gossiaux A, Mehring AS. Nutrient and stoichiometry dynamics of decomposing litter in stream ecosystems: A global synthesis. Ecology 2023:e4060. [PMID: 37186091 DOI: 10.1002/ecy.4060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 04/14/2023] [Indexed: 05/17/2023]
Abstract
Decomposing organic matter forms a substantial resource base fueling the biogeochemical function and secondary production of most aquatic ecosystems. However, detrital N (nitrogen) and P (phosphorus) dynamics remain relatively unexplored in aquatic relative to terrestrial ecosystems, despite fundamentally linking microbial processes to ecosystem function across broad spatial scales. We synthesized 217 published time series of detrital carbon (C), N, P, and their stoichiometric ratios (C:N, C:P, N:P) from stream ecosystems to analyze the temporal nutrient dynamics of decomposing litter using generalized additive models. Model results indicated that detritus was a net source of N (irrespective of inorganic or organic form) to the environment regardless of initial N content. In contrast, P sink/source dynamics were more strongly influenced by initial P content, where P-poor litters were sinks of nutrients until shifting to net P mineralization after ~40% mass loss. However, large variation surrounded both N and P predictions, suggesting the importance of non-microbial factors such as fragmentation by invertebrates. Detrital C:N ratios converged and became more similar toward the end of decomposition, suggesting predictable microbial functional effects throughout detrital ontogeny. C:P and N:P ratios also converged to some degree, but these model predictions were less robust than for C:N, due in part to the lower number of published detrital C:P time series. Explorations of environmental covariate effects were frequently limited by few coincident covariate measurements across studies, but temperature, N availability, and P tended to accelerate existing ontogenetic patterns in C:N. Our analysis helps unite organic matter decomposition across aquatic-terrestrial boundaries by describing basic patterns of elemental flows catalyzed by decomposition in streams, and points to a research agenda to continue addressing gaps in our knowledge of detrital nutrient dynamics across ecosystems. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Caleb J Robbins
- Department of Biology, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - David W P Manning
- Department of Biology, University of Nebraska at Omaha, Omaha, NE, USA
| | | | - Beth C Norman
- Lacawac Sanctuary Field Station and Environmental Education Center, Lake Ariel, PA, USA
| | - Rebecca A Eckert
- Biology Department, Environmental Studies Department, Gettysburg College, Gettysburg, PA, USA
| | - Ada Pastor
- Group of Continental Aquatic Ecology Research (GRECO), Institute of Aquatic Ecology, University of Girona, Girona, Spain
| | - Allyn K Dodd
- Arkansas School for Math, Sciences, and the Arts, Hot Springs, AR, USA
| | - Jérémy Jabiol
- HYFE - Hydrobiologie et Fonctionnement des Ecosystèmes, Elven, France
| | - Elliot Bastias
- Department of Ecology and Environmental Sciences, Umeå University, Umeå, Sweden
| | | | - Andrew S Mehring
- Department of Biology, University of Louisville, Louisville, KY, USA
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Rideout NK, Compson ZG, Monk WA, Bruce MR, Hajibabaei M, Porter TM, Wright MTG, Baird DJ. Environmental filtering of macroinvertebrate traits influences ecosystem functioning in a large river floodplain. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Natalie K. Rideout
- Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
| | - Zacchaeus G. Compson
- Environment and Climate Change Canada @ Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
- Department of Biological Sciences, Advanced Environmental Research Institute University of North Texas Denton TX USA
| | - Wendy A. Monk
- Environment and Climate Change Canada @ Canadian Rivers Institute, Faculty of Forestry and Environmental Management University of New Brunswick Fredericton NB Canada
| | - Meghann R. Bruce
- Canadian Rivers Institute @ University of New Brunswick Fredericton NB Canada
| | - Mehrdad Hajibabaei
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Teresita M. Porter
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Michael T. G. Wright
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Donald J. Baird
- Environment and Climate Change Canada @ Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
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Fenoy E, Pradhan A, Pascoal C, Rubio-Ríos J, Batista D, Moyano-López FJ, Cássio F, Casas JJ. Elevated temperature may reduce functional but not taxonomic diversity of fungal assemblages on decomposing leaf litter in streams. GLOBAL CHANGE BIOLOGY 2022; 28:115-127. [PMID: 34651383 DOI: 10.1111/gcb.15931] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 08/02/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Mounting evidence points to a linkage between biodiversity and ecosystem functioning (B-EF). Global drivers, such as warming and nutrient enrichment, can alter species richness and composition of aquatic fungal assemblages associated with leaf-litter decomposition, a key ecosystem process in headwater streams. However, effects of biodiversity changes on ecosystem functions might be countered by the presumed high functional redundancy of fungal species. Here, we examined how environmental variables and leaf-litter traits (based on leaf chemistry) affect taxonomic and functional α- and β-diversity of fungal decomposers. We analysed taxonomic diversity (DNA-fingerprinting profiles) and functional diversity (community-level physiological profiles) of fungal communities in four leaf-litter species from four subregions differing in stream-water characteristics and riparian vegetation. We hypothesized that increasing stream-water temperature and nutrients would alter taxonomic diversity more than functional diversity due to the functional redundancy among aquatic fungi. Contrary to our expectations, fungal taxonomic diversity varied little with stream-water characteristics across subregions, and instead taxon replacement occurred. Overall taxonomic β-diversity was fourfold higher than functional diversity, suggesting a high degree of functional redundancy among aquatic fungi. Elevated temperature appeared to boost assemblage uniqueness by increasing β-diversity while the increase in nutrient concentrations appeared to homogenize fungal assemblages. Functional richness showed a negative relationship with temperature. Nonetheless, a positive relationship between leaf-litter decomposition and functional richness suggests higher carbon use efficiency of fungal communities in cold waters.
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Affiliation(s)
- Encarnación Fenoy
- Department of Biology and Geology, University of Almería, Almería, Spain
- Andalusian Centre for Assessment and Monitoring of Global Change (CAESCG), Almería, Spain
| | - Arunava Pradhan
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Braga, Portugal
- Institute of Science and Innovation for Bio-sustainability, University of Minho, Braga, Portugal
| | - Cláudia Pascoal
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Braga, Portugal
- Institute of Science and Innovation for Bio-sustainability, University of Minho, Braga, Portugal
| | - Juan Rubio-Ríos
- Department of Biology and Geology, University of Almería, Almería, Spain
- Andalusian Centre for Assessment and Monitoring of Global Change (CAESCG), Almería, Spain
| | - Daniela Batista
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Braga, Portugal
- Institute of Science and Innovation for Bio-sustainability, University of Minho, Braga, Portugal
| | | | - Fernanda Cássio
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Braga, Portugal
- Institute of Science and Innovation for Bio-sustainability, University of Minho, Braga, Portugal
| | - J Jesús Casas
- Department of Biology and Geology, University of Almería, Almería, Spain
- Andalusian Centre for Assessment and Monitoring of Global Change (CAESCG), Almería, Spain
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Jeplawy JR, Cooper HF, Marks J, Lindroth RL, Andrews MI, Compson ZG, Gehring C, Hultine KR, Grady K, Whitham TG, Allan GJ, Best RJ. Plastic responses to hot temperatures homogenize riparian leaf litter, speed decomposition, and reduce detritivores. Ecology 2021; 102:e03461. [PMID: 34236702 DOI: 10.1002/ecy.3461] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/12/2021] [Accepted: 05/13/2021] [Indexed: 01/10/2023]
Abstract
Efforts to maintain the function of critical ecosystems under climate change often begin with foundation species. In the southwestern United States, cottonwood trees support diverse communities in riparian ecosystems that are threatened by rising temperatures. Genetic variation within cottonwoods shapes communities and ecosystems, but these effects may be modified by phenotypic plasticity, where genotype traits change in response to environmental conditions. Here, we investigated plasticity in Fremont cottonwood (Populus fremontii) leaf litter traits as well as the consequences of plasticity for riparian ecosystems. We used three common gardens each planted with genotypes from six genetically divergent populations spanning a 12°C temperature gradient, and a decomposition experiment in a common stream environment. We found that leaf litter area, specific leaf area, and carbon to nitrogen ratio (C:N) were determined by interactions between genetics and growing environment, as was the subsequent rate of litter decomposition. Most of the genetic variation in leaf litter traits appeared among rather than within source populations with distinct climate histories. Source populations from hotter climates generally produced litter that decomposed more quickly, but plasticity varied the magnitude of this effect. We also found that hotter growing conditions reduced the variation in litter traits produced across genotypes, homogenizing the litter inputs to riparian ecosystems. All genotypes in the hottest garden produced comparatively small leaves that decomposed quickly and supported lower abundances of aquatic invertebrates, whereas the same genotypes in the coldest garden produced litter with distinct morphologies and decomposition rates. Our results suggest that plastic responses to climate stress may constrict the expression of genetic variation in predictable ways that impact communities and ecosystems. Understanding these interactions between genetic and environmental variation is critical to our ability to plan for the role of foundation species when managing and restoring riparian ecosystems in a warming world.
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Affiliation(s)
- Joann R Jeplawy
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Tetra Tech, Inc., Denver, Colorado, 80202, USA
| | - Hillary F Cooper
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Jane Marks
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Richard L Lindroth
- Department of Entomology, University of Wisconsin-Madison, Madison, Wisconsin, 53706, USA
| | - Morgan I Andrews
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Zacchaeus G Compson
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, Denton, Texas, 76203, USA
| | - Catherine Gehring
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, Arizona, 85008, USA
| | - Kevin Grady
- Department of Forestry, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Thomas G Whitham
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Gerard J Allan
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Rebecca J Best
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA
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The Influence of Leaf Type on Carbon and Nitrogen Assimilation by Aquatic Invertebrate Communities: A New Perspective on Trophic Efficiency. Ecosystems 2020. [DOI: 10.1007/s10021-020-00550-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Marks JC. Revisiting the Fates of Dead Leaves That Fall into Streams. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019. [DOI: 10.1146/annurev-ecolsys-110218-024755] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As terrestrial leaf litter decomposes in rivers, its constituent elements follow multiple pathways. Carbon leached as dissolved organic matter can be quickly taken up by microbes, then respired before it can be transferred to the macroscopic food web. Alternatively, this detrital carbon can be ingested and assimilated by aquatic invertebrates, so it is retained longer in the stream and transferred to higher trophic levels. Microbial growth on litter can affect invertebrates through three pathways, which are not mutually exclusive. First, microbes can facilitate invertebrate feeding, improving food quality by conditioning leaves and making them more palatable for invertebrates. Second, microbes can be prey for invertebrates. Third, microbes can compete with invertebrates for resources bound within litter and may produce compounds that retard carbon and nitrogen fluxes to invertebrates. As litter is broken down into smaller particles, there are many opportunities for its elements to reenter the stream food web. Here, I describe a conceptual framework for evaluating how traits of leaf litter will affect its fate in food webs and ecosystems that is useful for predicting how global change will alter carbon fluxes into and out of streams.
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Affiliation(s)
- Jane C. Marks
- Department of Biological Sciences and Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona 86011, USA
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