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Langley JA, Wang L, Yedman B, Megonigal JP. Rising plant demand strengthens nitrogen limitation in tidal marsh. GLOBAL CHANGE BIOLOGY 2024; 30:e17342. [PMID: 38804198 DOI: 10.1111/gcb.17342] [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: 01/03/2024] [Revised: 04/12/2024] [Accepted: 04/26/2024] [Indexed: 05/29/2024]
Abstract
Nitrogen (N) is a limiting nutrient for primary productivity in most terrestrial ecosystems, but whether N limitation is strengthening or weakening remains controversial because both N sources and sinks are increasing in magnitude globally. Temperate marshes are exposed to greater amounts of external N inputs than most terrestrial ecosystems and more than in preindustrial times owing to their position downstream of major sources of human-derived N runoff along river mouths and estuaries. Simultaneously, ecosystem N demand may also be increasing owing to other global changes such as rising atmospheric [CO2]. Here, we used interannual variability in external drivers and variables related to exogenous supply of N, along with detailed assessments of plant growth and porewater biogeochemistry, to assess the severity of N-limitation, and to determine its causes, in a 14-year N-addition × elevated CO2 experiment. We found substantial interannual variability in porewater [N], plant growth, and experimental N effects on plant growth, but the magnitude of N pools through time varied independently of the strength of N limitation. Sea level, and secondarily salinity, related closely to interannual variability in growth of the dominant plant functional groups which drove patterns in N limitation and in porewater [N]. Experimental exposure of plants to elevated CO2 and years with high flooding strengthened N limitation for the sedge. Abiotic variables controlled plant growth, which determined the strength of N limitation for each plant species and for ecosystem productivity as a whole. We conclude that in this ecosystem, which has an open N cycle and where N inputs are likely greater than in preindustrial times, plant N demand has increased more than supply.
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Affiliation(s)
- J A Langley
- Department of Biology and Center for Biodiversity & Ecosystem Stewardship, Villanova University, Villanova, Pennsylvania, USA
| | - L Wang
- Department of Mathematics, Statistics and Data Science, Loyola Marymount University, Los Angeles, California, USA
| | - B Yedman
- Department of Biology and Center for Biodiversity & Ecosystem Stewardship, Villanova University, Villanova, Pennsylvania, USA
| | - J P Megonigal
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
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2
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Wilcox KR, Chen A, Avolio ML, Butler EE, Collins S, Fisher R, Keenan T, Kiang NY, Knapp AK, Koerner SE, Kueppers L, Liang G, Lieungh E, Loik M, Luo Y, Poulter B, Reich P, Renwick K, Smith MD, Walker A, Weng E, Komatsu KJ. Accounting for herbaceous communities in process-based models will advance our understanding of "grassy" ecosystems. GLOBAL CHANGE BIOLOGY 2023; 29:6453-6477. [PMID: 37814910 DOI: 10.1111/gcb.16950] [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: 04/04/2023] [Accepted: 06/01/2023] [Indexed: 10/11/2023]
Abstract
Grassland and other herbaceous communities cover significant portions of Earth's terrestrial surface and provide many critical services, such as carbon sequestration, wildlife habitat, and food production. Forecasts of global change impacts on these services will require predictive tools, such as process-based dynamic vegetation models. Yet, model representation of herbaceous communities and ecosystems lags substantially behind that of tree communities and forests. The limited representation of herbaceous communities within models arises from two important knowledge gaps: first, our empirical understanding of the principles governing herbaceous vegetation dynamics is either incomplete or does not provide mechanistic information necessary to drive herbaceous community processes with models; second, current model structure and parameterization of grass and other herbaceous plant functional types limits the ability of models to predict outcomes of competition and growth for herbaceous vegetation. In this review, we provide direction for addressing these gaps by: (1) presenting a brief history of how vegetation dynamics have been developed and incorporated into earth system models, (2) reporting on a model simulation activity to evaluate current model capability to represent herbaceous vegetation dynamics and ecosystem function, and (3) detailing several ecological properties and phenomena that should be a focus for both empiricists and modelers to improve representation of herbaceous vegetation in models. Together, empiricists and modelers can improve representation of herbaceous ecosystem processes within models. In so doing, we will greatly enhance our ability to forecast future states of the earth system, which is of high importance given the rapid rate of environmental change on our planet.
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Affiliation(s)
- Kevin R Wilcox
- University of North Carolina Greensboro, Greensboro, North Carolina, USA
- University of Wyoming, Laramie, Wyoming, USA
| | - Anping Chen
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, Colorado, USA
| | - Meghan L Avolio
- Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ethan E Butler
- Department of Forest Resources, University of Minnesota, St. Paul, Minnesota, USA
| | - Scott Collins
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Rosie Fisher
- CICERO Centre for International Cimate Research, Forskningsparken, Oslo, Norway
| | - Trevor Keenan
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Nancy Y Kiang
- NASA Goddard Institute for Space Studies, New York, New York, USA
| | - Alan K Knapp
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, Colorado, USA
| | - Sally E Koerner
- University of North Carolina Greensboro, Greensboro, North Carolina, USA
| | - Lara Kueppers
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Guopeng Liang
- Department of Forest Resources, University of Minnesota, St. Paul, Minnesota, USA
| | - Eva Lieungh
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Michael Loik
- Department of Environmental Studies, University of California, Santa Cruz, California, USA
| | - Yiqi Luo
- School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
| | - Ben Poulter
- Biospheric Sciences Lab, NASA GSFC, Greenbelt, Maryland, USA
| | - Peter Reich
- Department of Forest Resources, University of Minnesota, St. Paul, Minnesota, USA
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | | | - Melinda D Smith
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, Colorado, USA
| | - Anthony Walker
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Ensheng Weng
- NASA Goddard Institute for Space Studies, New York, New York, USA
- Center for Climate Systems Research, Columbia University, New York, New York, USA
| | - Kimberly J Komatsu
- University of North Carolina Greensboro, Greensboro, North Carolina, USA
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3
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Number of simultaneously acting global change factors affects composition, diversity and productivity of grassland plant communities. Nat Commun 2022; 13:7811. [PMID: 36535931 PMCID: PMC9763497 DOI: 10.1038/s41467-022-35473-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 12/06/2022] [Indexed: 12/23/2022] Open
Abstract
Plant communities experience impacts of increasing numbers of global change factors (e.g., warming, eutrophication, pollution). Consequently, unpredictable global change effects could arise. However, information about multi-factor effects on plant communities is scarce. To test plant-community responses to multiple global change factors (GCFs), we subjected sown and transplanted-seedling communities to increasing numbers (0, 1, 2, 4, 6) of co-acting GCFs, and assessed effects of individual factors and increasing numbers of GCFs on community composition and productivity. GCF number reduced species diversity and evenness of both community types, whereas none of the individual factors alone affected these measures. In contrast, GCF number positively affected the productivity of the transplanted-seedling community. Our findings show that simultaneously acting GCFs can affect plant communities in ways differing from those expected from single factor effects, which may be due to biological effects, sampling effects, or both. Consequently, exploring the multifactorial nature of global change is crucial to better understand ecological impacts of global change.
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Bai Z, Jia A, Bai Z, Qu S, Zhang M, Kong L, Sun R, Wang M. Photovoltaic panels have altered grassland plant biodiversity and soil microbial diversity. Front Microbiol 2022; 13:1065899. [PMID: 36590393 PMCID: PMC9797687 DOI: 10.3389/fmicb.2022.1065899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 11/21/2022] [Indexed: 12/23/2022] Open
Abstract
Introduction Human concerns about fossil fuel depletion, energy security and environmental degradation have driven the rapid development of solar photovoltaic (PV) power generation. Most of the photovoltaic power generation plants are concentrated in desert, grassland and arable land, which means the change of land use type. However, there is still a gap in the research of the PV panel layout on grassland plant species diversity and ecological function. Methods In this study, Illumina high-throughput sequencing technology was used to investigate the effects of PV panel arrangement on grassland plant species diversity and soil microbial diversity. In view of the differences in the microclimate at different sites of the PV panels, quadrates were arranged in front edge (FE), beneath the center of each panel (BP), back edge (BE), the uncovered interspace adjacent to each panel (IS) and the undisturbed grassland around the PV panels (Control), respectively. Results PV panels (especially FE) significantly increased the total aboveground productivity (total AGB) and plant species diversity in grasslands. FE increased precipitation accumulation and plant species diversity directly and indirectly changed the diversity of soil bacterial and fungal communities. PV panels decreased the relative abundance of Actinobacteriota, while increased the relative abundance of Proteobacteria, Acidobacteriota, and Methylomirabilota. EC, Margalef' s richness and total AGB were the main factors affecting the composition of bacterial communities, while alkaline hydrolysis nitrogen (AN) and available phosphorus (AP) were the main factors affecting the composition of fungal communities. Discussion In conclusion, the arrangement of PV panels increased the plant species diversity and soil microorganisms in grassland. This study provides important information for further understanding the impact of PV panels on grassland ecosystem function and is of great significance for maintaining grassland ecosystem function.
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Affiliation(s)
- Zhenyin Bai
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Aomei Jia
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Zhenjian Bai
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Shanmin Qu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Meng Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Linghang Kong
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Renhao Sun
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Mingjun Wang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, China,*Correspondence: Mingjun Wang,
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Mueller KE, Ocheltree TW, Kray JA, Bushey JA, Blumenthal DM, Williams DG, Pendall E. Trading water for carbon in the future: Effects of elevated CO 2 and warming on leaf hydraulic traits in a semiarid grassland. GLOBAL CHANGE BIOLOGY 2022; 28:5991-6001. [PMID: 35751572 PMCID: PMC9544398 DOI: 10.1111/gcb.16314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The effects of climate change on plants and ecosystems are mediated by plant hydraulic traits, including interspecific and intraspecific variability of trait phenotypes. Yet, integrative and realistic studies of hydraulic traits and climate change are rare. In a semiarid grassland, we assessed the response of several plant hydraulic traits to elevated CO2 (+200 ppm) and warming (+1.5 to 3°C; day to night). For leaves of five dominant species (three graminoids and two forbs), and in replicated plots exposed to 7 years of elevated CO2 , warming, or ambient climate, we measured: stomatal density and size, xylem vessel size, turgor loss point, and water potential (pre-dawn). Interspecific differences in hydraulic traits were larger than intraspecific shifts induced by elevated CO2 and/or warming. Effects of elevated CO2 were greater than effects of warming, and interactions between treatments were weak or not detected. The forbs showed little phenotypic plasticity. The graminoids had leaf water potentials and turgor loss points that were 10% to 50% less negative under elevated CO2 ; thus, climate change might cause these species to adjust their drought resistance strategy away from tolerance and toward avoidance. The C4 grass also reduced allocation of leaf area to stomata under elevated CO2 , which helps explain observations of higher soil moisture. The shifts in hydraulic traits under elevated CO2 were not, however, simply due to higher soil moisture. Integration of our results with others' indicates that common species in this grassland are more likely to adjust stomatal aperture in response to near-term climate change, rather than anatomical traits; this contrasts with apparent effects of changing CO2 on plant anatomy over evolutionary time. Future studies should assess how plant responses to drought may be constrained by the apparent shift from tolerance (via low turgor loss point) to avoidance (via stomatal regulation and/or access to deeper soil moisture).
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Affiliation(s)
- Kevin E. Mueller
- Department of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Troy W. Ocheltree
- Department of Forest and Rangeland StewardshipColorado State UniversityFort CollinsColoradoUSA
| | - Julie A. Kray
- Rangeland Resources & Systems Research, Agricultural Research Service, United States Department of AgricultureFort CollinsColoradoUSA
| | - Julie A. Bushey
- Water Management Research, Agricultural Research Service, United States Department of AgricultureFort CollinsColoradoUSA
| | - Dana M. Blumenthal
- Rangeland Resources & Systems Research, Agricultural Research Service, United States Department of AgricultureFort CollinsColoradoUSA
| | | | - Elise Pendall
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
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6
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Oburger E, Schmidt H, Staudinger C. Harnessing belowground processes for sustainable intensification of agricultural systems. PLANT AND SOIL 2022; 478:177-209. [PMID: 36277079 PMCID: PMC9579094 DOI: 10.1007/s11104-022-05508-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 05/18/2022] [Indexed: 06/16/2023]
Abstract
Increasing food demand coupled with climate change pose a great challenge to agricultural systems. In this review we summarize recent advances in our knowledge of how plants, together with their associated microbiota, shape rhizosphere processes. We address (molecular) mechanisms operating at the plant-microbe-soil interface and aim to link this knowledge with actual and potential avenues for intensifying agricultural systems, while at the same time reducing irrigation water, fertilizer inputs and pesticide use. Combining in-depth knowledge about above and belowground plant traits will not only significantly advance our mechanistic understanding of involved processes but also allow for more informed decisions regarding agricultural practices and plant breeding. Including belowground plant-soil-microbe interactions in our breeding efforts will help to select crops resilient to abiotic and biotic environmental stresses and ultimately enable us to produce sufficient food in a more sustainable agriculture in the upcoming decades.
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Affiliation(s)
- Eva Oburger
- Department of Forest and Soil Science, Institute of Soil Research, University of Natural Resources and Life Sciences, Konrad Lorenzstrasse 24, 3430 Tulln an der Donau, Austria
| | - Hannes Schmidt
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Christiana Staudinger
- Department of Forest and Soil Science, Institute of Soil Research, University of Natural Resources and Life Sciences, Konrad Lorenzstrasse 24, 3430 Tulln an der Donau, Austria
- Graduate School of Integrated Sciences for Life, Hiroshima University, Kagamiyama 1-7-1, Higashi-Hiroshima, Japan
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7
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Langley JA, Grman E, Wilcox KR, Avolio ML, Komatsu KJ, Collins SL, Koerner SE, Smith MD, Baldwin AH, Bowman W, Chiariello N, Eskelinen A, Harmens H, Hovenden M, Klanderud K, McCulley RL, Onipchenko VG, Robinson CH, Suding KN. Do tradeoffs govern plant species responses to different global change treatments? Ecology 2021; 103:e3626. [PMID: 34967948 DOI: 10.1002/ecy.3626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/21/2021] [Indexed: 11/07/2022]
Abstract
Plants are subject to tradeoffs among growth strategies such that adaptations for optimal growth in one condition can preclude optimal growth in another. Thus, we predicted that a plant species that responds positively to one global change treatment would be less likely than average to respond positively to another treatment, particularly for pairs of treatments that favor distinct traits. We examined plant species abundances in 39 global change experiments manipulating two or more of the following: CO2 , nitrogen, phosphorus, water, temperature, or disturbance. Overall, the directional response of a species to one treatment was 13% more likely than expected to oppose its response to a another single-factor treatment. This tendency was detectable across the global dataset but held little predictive power for individual treatment combinations or within individual experiments. While tradeoffs in the ability to respond to different global change treatments exert discernible global effects, other forces obscure their influence in local communities. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- J Adam Langley
- Department of Biology, Center of Biodiversity and Ecosystem Stewardship, Villanova, PA
| | - Emily Grman
- Department of Biology, Eastern Michigan University, Ypsilanti, MI, USA
| | - Kevin R Wilcox
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY
| | - Meghan L Avolio
- Department of Earth and Planetary Sciences, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD
| | - Kimberly J Komatsu
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD, USA
| | | | | | - Melinda D Smith
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Andrew H Baldwin
- Department of Environmental Science and Technology, University of Maryland, College Park, MD
| | - William Bowman
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - Nona Chiariello
- Jasper Ridge Biological Preserve, Stanford, Stanford, CA, USA
| | - Anu Eskelinen
- Helmholtz Centre for Environmental Research UFZ, Leipzig, Germany, German Centre for Integrative Biodiversity Research iDiv, Leipzig, Germany, Ecology and Genetics Unit, University of Oulu, Finland
| | - Harry Harmens
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd, UK
| | - Mark Hovenden
- Biological Sciences, School of Natural Sciences, University of Tasmania, Locked Bag 55, Hobart, Tasmania, Australia
| | - Kari Klanderud
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Aas, Norway
| | - Rebecca L McCulley
- Department of Plant & Soil Sciences, University of Kentucky, Lexington, KY, USA
| | | | - Clare H Robinson
- Department of Earth & Environmental Sciences, The University of Manchester, Manchester, UK
| | - Katharine N Suding
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO
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8
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Avolio ML, Komatsu KJ, Collins SL, Grman E, Koerner SE, Tredennick AT, Wilcox KR, Baer S, Boughton EH, Britton AJ, Foster B, Gough L, Hovenden M, Isbell F, Jentsch A, Johnson DS, Knapp AK, Kreyling J, Langley JA, Lortie C, McCulley RL, McLaren JR, Reich PB, Seabloom EW, Smith MD, Suding KN, Suttle KB, Tognetti PM. Determinants of community compositional change are equally affected by global change. Ecol Lett 2021; 24:1892-1904. [PMID: 34170615 DOI: 10.1111/ele.13824] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/21/2021] [Accepted: 04/28/2021] [Indexed: 11/28/2022]
Abstract
Global change is impacting plant community composition, but the mechanisms underlying these changes are unclear. Using a dataset of 58 global change experiments, we tested the five fundamental mechanisms of community change: changes in evenness and richness, reordering, species gains and losses. We found 71% of communities were impacted by global change treatments, and 88% of communities that were exposed to two or more global change drivers were impacted. Further, all mechanisms of change were equally likely to be affected by global change treatments-species losses and changes in richness were just as common as species gains and reordering. We also found no evidence of a progression of community changes, for example, reordering and changes in evenness did not precede species gains and losses. We demonstrate that all processes underlying plant community composition changes are equally affected by treatments and often occur simultaneously, necessitating a wholistic approach to quantifying community changes.
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Affiliation(s)
- Meghan L Avolio
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Kimberly J Komatsu
- Smithsonian Environmental Research Center, Smithsonian Institution, Edgewater, MD, USA
| | - Scott L Collins
- Department of Biology, University of New Mexico, Albuquerque, NM, USA
| | - Emily Grman
- Department of Biology, Eastern Michigan University, Ypsilanti, MI, USA
| | - Sally E Koerner
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Andrew T Tredennick
- Department of Statistics, Western EcoSystems Technology, Inc, Laramie, WY, USA
| | - Kevin R Wilcox
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY, USA
| | - Sara Baer
- Kansas Biological Survey and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA
| | | | | | - Bryan Foster
- Ecology and Evolutionary Biology and Kansas Biological Survey, University of Kansas, Lawrence, KS, USA
| | - Laura Gough
- Department of Biological Sciences, Towson University, Towson, MD, USA
| | - Mark Hovenden
- Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Forest Isbell
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Anke Jentsch
- Department of Disturbance Ecology, University of Bayreuth, Center of Ecology and Environmental Research (BayCEER), Bayreuth, Germany
| | - David S Johnson
- Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA, USA
| | - Alan K Knapp
- Department of Biology, Colorado State University, Fort Collins, CO, USA.,Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Juergen Kreyling
- Experimental Plant Ecology, Institute for Botany and Landscape Ecology, University of Greifswald, Greifswald, Germany
| | - J Adam Langley
- Department of Biology, Center for Biodiversity and Ecosystem Stewardship, Villanova University, Villanova, PA, USA
| | - Christopher Lortie
- The National Center for Ecological Analysis and Synthesis, UCSB, Santa Barbara, CA, USA
| | - Rebecca L McCulley
- Department of Plant & Soil Sciences, University of Kentucky, Lexington, KY, USA
| | - Jennie R McLaren
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, USA
| | - Peter B Reich
- Department Forest Resources, University of Minnesota, Saint Paul, MN, USA.,Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Eric W Seabloom
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Melinda D Smith
- Department of Biology, Colorado State University, Fort Collins, CO, USA.,Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Katharine N Suding
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - K Blake Suttle
- Angelo Coast Range Reserve, University of California Natural Reserve System, Branscomb, CA, USA
| | - Pedro M Tognetti
- IFEVA, Facultad de Agronomía, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
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9
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Pec GJ, Diepen LTA, Knorr M, Grandy AS, Melillo JM, DeAngelis KM, Blanchard JL, Frey SD. Fungal community response to long‐term soil warming with potential implications for soil carbon dynamics. Ecosphere 2021. [DOI: 10.1002/ecs2.3460] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Gregory J. Pec
- Department of Natural Resources and the Environment University of New Hampshire Durham New Hampshire03824USA
| | - Linda T. A. Diepen
- Department of Ecosystem Science and Management University of Wyoming Laramie Wyoming82071USA
| | - Melissa Knorr
- Department of Natural Resources and the Environment University of New Hampshire Durham New Hampshire03824USA
| | - A. Stuart Grandy
- Department of Natural Resources and the Environment University of New Hampshire Durham New Hampshire03824USA
| | - Jerry M. Melillo
- The Ecosystems Center Marine Biological Laboratory Woods Hole Massachusetts02543USA
| | - Kristen M. DeAngelis
- Department of Microbiology University of Massachusetts Amherst Massachusetts01003USA
| | | | - Serita D. Frey
- Department of Natural Resources and the Environment University of New Hampshire Durham New Hampshire03824USA
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10
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Multiple constraints cause positive and negative feedbacks limiting grassland soil CO 2 efflux under CO 2 enrichment. Proc Natl Acad Sci U S A 2020; 118:2008284117. [PMID: 33419921 DOI: 10.1073/pnas.2008284117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Terrestrial ecosystems are increasingly enriched with resources such as atmospheric CO2 that limit ecosystem processes. The consequences for ecosystem carbon cycling depend on the feedbacks from other limiting resources and plant community change, which remain poorly understood for soil CO2 efflux, JCO2, a primary carbon flux from the biosphere to the atmosphere. We applied a unique CO2 enrichment gradient (250 to 500 µL L-1) for eight years to grassland plant communities on soils from different landscape positions. We identified the trajectory of JCO2 responses and feedbacks from other resources, plant diversity [effective species richness, exp(H)], and community change (plant species turnover). We found linear increases in JCO2 on an alluvial sandy loam and a lowland clay soil, and an asymptotic increase on an upland silty clay soil. Structural equation modeling identified CO2 as the dominant limitation on JCO2 on the clay soil. In contrast with theory predicting limitation from a single limiting factor, the linear JCO2 response on the sandy loam was reinforced by positive feedbacks from aboveground net primary productivity and exp(H), while the asymptotic JCO2 response on the silty clay arose from a net negative feedback among exp(H), species turnover, and soil water potential. These findings support a multiple resource limitation view of the effects of global change drivers on grassland ecosystem carbon cycling and highlight a crucial role for positive or negative feedbacks between limiting resources and plant community structure. Incorporating these feedbacks will improve models of terrestrial carbon sequestration and ecosystem services.
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11
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Wilcox KR, Komatsu KJ, Avolio ML. Improving collaborations between empiricists and modelers to advance grassland community dynamics in ecosystem models. THE NEW PHYTOLOGIST 2020; 228:1467-1471. [PMID: 33460147 DOI: 10.1111/nph.16900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- Kevin R Wilcox
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY, 82071, USA
| | | | - Meghan L Avolio
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD, 21218, USA
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12
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Avolio ML, Carroll IT, Collins SL, Houseman GR, Hallett LM, Isbell F, Koerner SE, Komatsu KJ, Smith MD, Wilcox KR. A comprehensive approach to analyzing community dynamics using rank abundance curves. Ecosphere 2019. [DOI: 10.1002/ecs2.2881] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Meghan L. Avolio
- Department of Earth and Planetary Sciences Johns Hopkins University Baltimore Maryland 21218 USA
- National Socio‐Environmental Synthesis Center (SESYNC) Annapolis Maryland 21401 USA
| | - Ian T. Carroll
- National Socio‐Environmental Synthesis Center (SESYNC) Annapolis Maryland 21401 USA
| | - Scott L. Collins
- Department of Biology University of New Mexico Albuquerque New Mexico 87131 USA
| | - Gregory R. Houseman
- Department of Biological Sciences Wichita State University Wichita Kansas 67026 USA
| | - Lauren M. Hallett
- Environmental Studies Program and Department of Biology University of Oregon Eugene Oregon 97403 USA
| | - Forest Isbell
- Department of Ecology, Evolution and Behavior University of Minnesota Saint Paul Minnesota 55108 USA
| | - Sally E. Koerner
- Department of Biology University of North Carolina Greensboro North Carolina 27402 USA
| | | | - Melinda D. Smith
- Department of Biology and Graduate Degree Program in Ecology Colorado State University Fort Collins Colorado 80523 USA
| | - Kevin R. Wilcox
- U.S. Department of Agriculture Agriculture Research Service Fort Collins Colorado 80526 USA
- Department of Ecosystem Science and Management University of Wyoming Laramie Wyoming 80521 USA
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13
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Chen JM, Ju W, Ciais P, Viovy N, Liu R, Liu Y, Lu X. Vegetation structural change since 1981 significantly enhanced the terrestrial carbon sink. Nat Commun 2019; 10:4259. [PMID: 31534135 PMCID: PMC6751163 DOI: 10.1038/s41467-019-12257-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 08/30/2019] [Indexed: 11/16/2022] Open
Abstract
Satellite observations show that leaf area index (LAI) has increased globally since 1981, but the impact of this vegetation structural change on the global terrestrial carbon cycle has not been systematically evaluated. Through process-based diagnostic ecosystem modeling, we find that the increase in LAI alone was responsible for 12.4% of the accumulated terrestrial carbon sink (95 ± 5 Pg C) from 1981 to 2016, whereas other drivers of CO2 fertilization, nitrogen deposition, and climate change (temperature, radiation, and precipitation) contributed to 47.0%, 1.1%, and −28.6% of the sink, respectively. The legacy effects of past changes in these drivers prior to 1981 are responsible for the remaining 65.5% of the accumulated sink from 1981 to 2016. These results refine the attribution of the land sink to the various drivers and would help constrain prognostic models that often have large uncertainties in simulating changes in vegetation and their impacts on the global carbon cycle. There lacks systematic analysis on the importance of vegetation structural change in the global terrestrial carbon cycle. Here the authors conducted a multi-model comparison analysis and find that the increase in leaf area index has been responsible for 12.4% of the accumulated terrestrial carbon sink from 1981 to 2016.
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Affiliation(s)
- Jing M Chen
- Department of Geography and Program in Planning, University of Toronto, Toronto, ON, M5S 3G3, Canada.,Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, International Institute for Earth System Science, Nanjing University, Nanjing, 210023, China
| | - Weimin Ju
- Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, International Institute for Earth System Science, Nanjing University, Nanjing, 210023, China. .,Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application, Nanjing, 210023, China.
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Universite Paris-Saclay, F-91191, Gif-sur-Yvette, France
| | - Nicolas Viovy
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Universite Paris-Saclay, F-91191, Gif-sur-Yvette, France
| | - Ronggao Liu
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yang Liu
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xuehe Lu
- Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, International Institute for Earth System Science, Nanjing University, Nanjing, 210023, China
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14
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Global change effects on plant communities are magnified by time and the number of global change factors imposed. Proc Natl Acad Sci U S A 2019; 116:17867-17873. [PMID: 31427510 DOI: 10.1073/pnas.1819027116] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (<10 y). In contrast, long-term (≥10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity-ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously.
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15
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Polley HW, Aspinwall MJ, Collins HP, Gibson AE, Gill RA, Jackson RB, Jin VL, Khasanova AR, Reichmann LG, Fay PA. CO 2 enrichment and soil type additively regulate grassland productivity. THE NEW PHYTOLOGIST 2019; 222:183-192. [PMID: 30367488 DOI: 10.1111/nph.15562] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 10/18/2018] [Indexed: 06/08/2023]
Abstract
Atmospheric CO2 enrichment usually increases the aboveground net primary productivity (ANPP) of grassland vegetation, but the magnitude of the ANPP-CO2 response differs among ecosystems. Soil properties affect ANPP via multiple mechanisms and vary over topographic to geographic gradients, but have received little attention as potential modifiers of the ANPP-CO2 response. We assessed the effects of three soil types, sandy loam, silty clay and clay, on the ANPP response of perennial C3 /C4 grassland communities to a subambient to elevated CO2 gradient over 10 yr in Texas, USA. We predicted an interactive, rather than additive, effect of CO2 and soil type on ANPP. Contrary to prediction, CO2 and soil additively influenced grassland ANPP. Increasing CO2 by 250 μl l-1 increased ANPP by 170 g m-2 across soil types. Increased clay content from 10% to 50% among soils reduced ANPP by 50 g m-2 . CO2 enrichment increased ANPP via a predominant direct effect, accompanied by a smaller indirect effect mediated by a successional shift to increased dominance of the C4 tallgrass Sorghastrum nutans. Our results indicate a large, positive influence of CO2 enrichment on grassland productivity that resulted from the direct physiological benefits of CO2 augmented by species succession, and was expressed similarly across soils of differing physical properties.
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Affiliation(s)
- H Wayne Polley
- Agricultural Research Service, Grassland, Soil and Water Research Laboratory, USDA, 808 East Blackland Road, Temple, TX, 76502, USA
| | - Michael J Aspinwall
- Section of Integrative Biology, The University of Texas at Austin, 1 University Station C0930, Austin, TX, 78712, USA
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL, 32224, USA
| | - Harold P Collins
- Agricultural Research Service, Grassland, Soil and Water Research Laboratory, USDA, 808 East Blackland Road, Temple, TX, 76502, USA
| | - Anne E Gibson
- Agricultural Research Service, Grassland, Soil and Water Research Laboratory, USDA, 808 East Blackland Road, Temple, TX, 76502, USA
| | - Richard A Gill
- Department of Biology, Brigham Young University, 4102 LSB, Provo, UT, 84602, USA
| | - Robert B Jackson
- Department of Earth System Science, Woods Institute for the Environment and Precourt Institute for Energy, Stanford University, Y2E2 Building, 379B, Stanford, CA, 94305, USA
| | - Virginia L Jin
- Agricultural Research Service, ARS Agroecosystem Management Research Unit, USDA, University of Nebraska, 251 Filley Hall, Lincoln, NE, 68583, USA
| | - Albina R Khasanova
- Section of Integrative Biology, The University of Texas at Austin, 1 University Station C0930, Austin, TX, 78712, USA
| | - Lara G Reichmann
- Section of Integrative Biology, The University of Texas at Austin, 1 University Station C0930, Austin, TX, 78712, USA
- Data Institute, University of San Francisco, 101 Howard St., San Francisco, CA, 94105, USA
| | - Philip A Fay
- Agricultural Research Service, Grassland, Soil and Water Research Laboratory, USDA, 808 East Blackland Road, Temple, TX, 76502, USA
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16
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Song J, Wan S, Piao S, Hui D, Hovenden MJ, Ciais P, Liu Y, Liu Y, Zhong M, Zheng M, Ma G, Zhou Z, Ru J. Elevated CO2
does not stimulate carbon sink in a semi-arid grassland. Ecol Lett 2019; 22:458-468. [DOI: 10.1111/ele.13202] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 07/17/2018] [Accepted: 10/23/2018] [Indexed: 01/19/2023]
Affiliation(s)
- Jian Song
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
- College of Life Sciences; Hebei University; Baoding Hebei 071002 China
| | - Shiqiang Wan
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
- College of Life Sciences; Hebei University; Baoding Hebei 071002 China
| | - Shilong Piao
- Sino-French Institute for Earth System Science; College of Urban and Environmental Sciences; Peking University; Beijing 100871 China
- Key Laboratory of Alpine Ecology and Biodiversity; Institute of Tibetan Plateau Research; Chinese Academy of Sciences; Beijing 100085 China
- Centre for Excellence in Tibetan Earth Science; Chinese Academy of Sciences; Beijing 100085 China
| | - Dafeng Hui
- Department of Biological Sciences; Tennessee State University; Nashville TN 37209 USA
| | - Mark J. Hovenden
- Biological Sciences; School of Natural Sciences; University of Tasmania; Private Bag 55 Hobart Tas 7001 Australia
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement; CEA CNRS UVSQ; Gif-sur-Yvette France
| | - Yongwen Liu
- Key Laboratory of Alpine Ecology and Biodiversity; Institute of Tibetan Plateau Research; Chinese Academy of Sciences; Beijing 100101 China
| | - Yinzhan Liu
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
| | - Mingxing Zhong
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
| | - Mengmei Zheng
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
| | - Gaigai Ma
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
| | - Zhenxing Zhou
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
| | - Jingyi Ru
- International Joint Research Laboratory for Global Change Ecology; School of Life Sciences; Henan University; Kaifeng Henan 475004 China
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17
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Langley JA, Chapman SK, La Pierre KJ, Avolio M, Bowman WD, Johnson DS, Isbell F, Wilcox KR, Foster BL, Hovenden MJ, Knapp AK, Koerner SE, Lortie CJ, Megonigal JP, Newton PCD, Reich PB, Smith MD, Suttle KB, Tilman D. Ambient changes exceed treatment effects on plant species abundance in global change experiments. GLOBAL CHANGE BIOLOGY 2018; 24:5668-5679. [PMID: 30369019 DOI: 10.1111/gcb.14442] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
The responses of species to environmental changes will determine future community composition and ecosystem function. Many syntheses of global change experiments examine the magnitude of treatment effect sizes, but we lack an understanding of how plant responses to treatments compare to ongoing changes in the unmanipulated (ambient or background) system. We used a database of long-term global change studies manipulating CO2 , nutrients, water, and temperature to answer three questions: (a) How do changes in plant species abundance in ambient plots relate to those in treated plots? (b) How does the magnitude of ambient change in species-level abundance over time relate to responsiveness to global change treatments? (c) Does the direction of species-level responses to global change treatments differ from the direction of ambient change? We estimated temporal trends in plant abundance for 791 plant species in ambient and treated plots across 16 long-term global change experiments yielding 2,116 experiment-species-treatment combinations. Surprisingly, for most species (57%) the magnitude of ambient change was greater than the magnitude of treatment effects. However, the direction of ambient change, whether a species was increasing or decreasing in abundance under ambient conditions, had no bearing on the direction of treatment effects. Although ambient communities are inherently dynamic, there is now widespread evidence that anthropogenic drivers are directionally altering plant communities in many ecosystems. Thus, global change treatment effects must be interpreted in the context of plant species trajectories that are likely driven by ongoing environmental changes.
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Affiliation(s)
- J Adam Langley
- Department of Biology, Villanova University, Villanova, Pennsylvania
| | | | | | - Meghan Avolio
- Department of Earth & Planetary Sciences, Johns Hopkins University, Baltimore, Maryland
| | - William D Bowman
- Department of Ecology and Evolutionary Biology and Mountain Research Station, University of Colorado, Boulder, Colorado
| | - David S Johnson
- Virginia Institute of Marine Science, Gloucester Point, Virginia
| | - Forest Isbell
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota
| | - Kevin R Wilcox
- U.S. Department of Agriculture, Agriculture Research Service, Fort Collins, Colorado
| | - Bryan L Foster
- Ecology and Evolutionary Biology and Kansas Biological Survey, University of Kansas, Lawrence, Kansas
| | - Mark J Hovenden
- Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Alan K Knapp
- Department of Biology and Graduate Degree Program in Ecology, Fort Collins, Colorado
| | - Sally E Koerner
- Department of Biology, University of North Carolina Greensboro, Greensboro, North Carolina
| | - Christopher J Lortie
- The National Center for Ecological Analysis and Synthesis, UCSB, Santa Barbara, California
| | | | | | - Peter B Reich
- Department of Forest Resources, University of Minnesota, St. Paul, Minnesota
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Melinda D Smith
- Department of Biology and Graduate Degree Program in Ecology, Fort Collins, Colorado
| | - Kenwyn B Suttle
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California
| | - David Tilman
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota
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18
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Fatichi S, Leuzinger S, Paschalis A, Langley JA, Donnellan Barraclough A, Hovenden MJ. Partitioning direct and indirect effects reveals the response of water-limited ecosystems to elevated CO 2. Proc Natl Acad Sci U S A 2016; 113:12757-12762. [PMID: 27791074 PMCID: PMC5111654 DOI: 10.1073/pnas.1605036113] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Increasing concentrations of atmospheric carbon dioxide are expected to affect carbon assimilation and evapotranspiration (ET), ultimately driving changes in plant growth, hydrology, and the global carbon balance. Direct leaf biochemical effects have been widely investigated, whereas indirect effects, although documented, elude explicit quantification in experiments. Here, we used a mechanistic model to investigate the relative contributions of direct (through carbon assimilation) and indirect (via soil moisture savings due to stomatal closure, and changes in leaf area index) effects of elevated CO2 across a variety of ecosystems. We specifically determined which ecosystems and climatic conditions maximize the indirect effects of elevated CO2 The simulations suggest that the indirect effects of elevated CO2 on net primary productivity are large and variable, ranging from less than 10% to more than 100% of the size of direct effects. For ET, indirect effects were, on average, 65% of the size of direct effects. Indirect effects tended to be considerably larger in water-limited ecosystems. As a consequence, the total CO2 effect had a significant, inverse relationship with the wetness index and was directly related to vapor pressure deficit. These results have major implications for our understanding of the CO2 response of ecosystems and for global projections of CO2 fertilization, because, although direct effects are typically understood and easily reproducible in models, simulations of indirect effects are far more challenging and difficult to constrain. Our findings also provide an explanation for the discrepancies between experiments in the total CO2 effect on net primary productivity.
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Affiliation(s)
- Simone Fatichi
- Institute of Environmental Engineering, ETH Zurich, 8093 Zurich, Switzerland;
| | - Sebastian Leuzinger
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland 1010, New Zealand
| | - Athanasios Paschalis
- Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ, United Kingdom
- Nicholas School of the Environment, Duke University, Durham, NC 27708
| | - J Adam Langley
- Department of Biology, Villanova University, Villanova, PA 19085
| | - Alicia Donnellan Barraclough
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland 1010, New Zealand
| | - Mark J Hovenden
- School of Biological Sciences, University of Tasmania, Hobart, 7005 TAS, Australia
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19
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Nonlinear, interacting responses to climate limit grassland production under global change. Proc Natl Acad Sci U S A 2016; 113:10589-94. [PMID: 27601643 DOI: 10.1073/pnas.1606734113] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Global changes in climate, atmospheric composition, and pollutants are altering ecosystems and the goods and services they provide. Among approaches for predicting ecosystem responses, long-term observations and manipulative experiments can be powerful approaches for resolving single-factor and interactive effects of global changes on key metrics such as net primary production (NPP). Here we combine both approaches, developing multidimensional response surfaces for NPP based on the longest-running, best-replicated, most-multifactor global-change experiment at the ecosystem scale-a 17-y study of California grassland exposed to full-factorial warming, added precipitation, elevated CO2, and nitrogen deposition. Single-factor and interactive effects were not time-dependent, enabling us to analyze each year as a separate realization of the experiment and extract NPP as a continuous function of global-change factors. We found a ridge-shaped response surface in which NPP is humped (unimodal) in response to temperature and precipitation when CO2 and nitrogen are ambient, with peak NPP rising under elevated CO2 or nitrogen but also shifting to lower temperatures. Our results suggest that future climate change will push this ecosystem away from conditions that maximize NPP, but with large year-to-year variability.
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20
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Pastore MA, Megonigal JP, Langley JA. Elevated CO2 promotes long-term nitrogen accumulation only in combination with nitrogen addition. GLOBAL CHANGE BIOLOGY 2016; 22:391-403. [PMID: 26577708 DOI: 10.1111/gcb.13112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/25/2015] [Accepted: 09/13/2015] [Indexed: 06/05/2023]
Abstract
Biogeochemical models that incorporate nitrogen (N) limitation indicate that N availability will control the magnitude of ecosystem carbon uptake in response to rising CO2 . Some models, however, suggest that elevated CO2 may promote ecosystem N accumulation, a feedback that in the long term could circumvent N limitation of the CO2 response while mitigating N pollution. We tested this prediction using a nine-year CO2 xN experiment in a tidal marsh. Although the effects of CO2 are similar between uplands and wetlands in many respects, this experiment offers a greater likelihood of detecting CO2 effects on N retention on a decadal timescale because tidal marshes have a relatively open N cycle and can accrue soil organic matter rapidly. To determine how elevated CO2 affects N dynamics, we assessed the three primary fates of N in a tidal marsh: (1) retention in plants and soil, (2) denitrification to the atmosphere, and (3) tidal export. We assessed changes in N pools and tracked the fate of a (15) N tracer added to each plot in 2006 to quantify the fraction of added N retained in vegetation and soil, and to estimate lateral N movement. Elevated CO2 alone did not increase plant N mass, soil N mass, or (15) N label retention. Unexpectedly, CO2 and N interacted such that the combined N+CO2 treatment increased ecosystem N accumulation despite the stimulation in N losses indicated by reduced (15) N label retention. These findings suggest that in N-limited ecosystems, elevated CO2 is unlikely to increase long-term N accumulation and circumvent progressive N limitation without additional N inputs, which may relieve plant-microbe competition and allow for increased plant N uptake.
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Affiliation(s)
- Melissa A Pastore
- Department of Biology, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA
| | - J Patrick Megonigal
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD, 21037, USA
| | - J Adam Langley
- Department of Biology, Villanova University, 800 Lancaster Avenue, Villanova, PA, 19085, USA
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD, 21037, USA
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21
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Classen AT, Sundqvist MK, Henning JA, Newman GS, Moore JAM, Cregger MA, Moorhead LC, Patterson CM. Direct and indirect effects of climate change on soil microbial and soil microbial-plant interactions: What lies ahead? Ecosphere 2015. [DOI: 10.1890/es15-00217.1] [Citation(s) in RCA: 337] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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22
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Gornish ES, Leuzinger S. Introduction to the Special Issue: Across the horizon: scale effects in global change research. AOB PLANTS 2015; 7:plv079. [PMID: 26174145 PMCID: PMC4564050 DOI: 10.1093/aobpla/plv079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 07/03/2015] [Indexed: 06/04/2023]
Abstract
As a result of the increasing speed and magnitude in which habitats worldwide are experiencing environmental change, making accurate predictions of the effects of global change on ecosystems and the organisms that inhabit them have become an important goal for ecologists. Experimental and modelling approaches aimed at understanding the linkages between factors of global change and biotic responses have become numerous and increasingly complex in order to adequately capture the multifarious dynamics associated with these relationships. However, constrained by resources, experiments are often conducted at small spatiotemporal scales (e.g. looking at a plot of a few square metres over a few years) and at low organizational levels (looking at organisms rather than ecosystems) in spite of both theoretical and experimental work that suggests ecological dynamics across scales can be dissimilar. This phenomenon has been hypothesized to occur because the mechanisms that drive dynamics across scales differ. A good example is the effect of elevated CO2 on transpiration. While at the leaf level, transpiration can be reduced, at the stand level, transpiration can increase because leaf area per unit ground area increases. The reported net effect is then highly dependent on the spatiotemporal scale. This special issue considers the biological relevancy inherent in the patterns associated with the magnitude and type of response to changing environmental conditions, across scales. This collection of papers attempts to provide a comprehensive treatment of this phenomenon in order to help develop an understanding of the extent of, and mechanisms involved with, ecological response to global change.
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Affiliation(s)
- Elise S Gornish
- Plant Sciences, University of California, Davis, CA 95616, USA
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