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Schmitz OJ, Leroux SJ. Food Webs and Ecosystems: Linking Species Interactions to the Carbon Cycle. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-011720-104730] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
All species within ecosystems contribute to regulating carbon cycling because of their functional integration into food webs. Yet carbon modeling and accounting still assumes that only plants, microbes, and invertebrate decomposer species are relevant to the carbon cycle. Our multifaceted review develops a case for considering a wider range of species, especially herbivorous and carnivorous wild animals. Animal control over carbon cycling is shaped by the animals’ stoichiometric needs and functional traits in relation to the stoichiometry and functional traits of their resources. Quantitative synthesis reveals that failing to consider these mechanisms can lead to serious inaccuracies in the carbon budget. Newer carbon-cycle models that consider food-web structure based on organismal functional traits and stoichiometry can offer mechanistically informed predictions about the magnitudes of animal effects that will help guide new empirical research aimed at developing a coherent understanding of the interactions and importance of all species within food webs.
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Affiliation(s)
- Oswald J. Schmitz
- School of the Environment, Yale University, New Haven, Connecticut 06511, USA
| | - Shawn J. Leroux
- Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland, A1B 3X9, Canada
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2
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Van Dievel M, Janssens L, Stoks R. Effects of pesticide exposure and predation risk on nutrient cycling and primary production. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135880. [PMID: 31972928 DOI: 10.1016/j.scitotenv.2019.135880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/26/2019] [Accepted: 11/30/2019] [Indexed: 06/10/2023]
Abstract
Understanding how pesticides and natural stressors shape ecosystem functions remains a major challenge. A largely overlooked way how stressors may affect nutrient cycling and primary production is through effects on body stoichiometry and the egestion of elements. We investigated how exposure to the pesticide chlorpyrifos and to predation risk, an abundant natural stressor in aquatic systems, altered the stoichiometry of the bodies and the egested faecal pellets of Enallagma cyathigerum damselfly larvae and how this further cascaded into effects on primary production (algae growth). Chlorpyrifos exposure reduced egestion rates while predation risk had no effect. Chlorpyrifos exposure and predation risk affected both elemental composition of bodies and faecal pellets, and this in an additive way. Chlorpyrifos exposure increased body C(carbon), N(nitrogen), and P(phosphorous) contents, and increased the C content of the faecal pellets. Predation risk induced an increase of the N content, resulting in a decreased C:N ratio, of both the bodies and faecal pellets. The changes in the composition of the faecal pellets caused by predation risk but not by chlorpyrifos exposure increased algae growth under control conditions. This indicated that algae growth was N limited. Our results provide an important proof-of-principle how a stressor may shape nutrient cycling and subsequently primary productivity.
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Affiliation(s)
- Marie Van Dievel
- Evolutionary Stress Ecology and Ecotoxicology, University of Leuven, Charles Deberiotstraat 32, B-3000 Leuven, Belgium
| | - Lizanne Janssens
- Evolutionary Stress Ecology and Ecotoxicology, University of Leuven, Charles Deberiotstraat 32, B-3000 Leuven, Belgium
| | - Robby Stoks
- Evolutionary Stress Ecology and Ecotoxicology, University of Leuven, Charles Deberiotstraat 32, B-3000 Leuven, Belgium.
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3
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Trophic Regulations of the Soil Microbiome. Trends Microbiol 2019; 27:771-780. [DOI: 10.1016/j.tim.2019.04.008] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/09/2019] [Accepted: 04/23/2019] [Indexed: 12/28/2022]
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4
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Simon TN, Binderup AJ, Flecker AS, Gilliam JF, Marshall MC, Thomas SA, Travis J, Reznick DN, Pringle CM. Landscape patterns in top-down control of decomposition: omnivory disrupts a tropical detrital-based trophic cascade. Ecology 2019; 100:e02723. [PMID: 30973962 DOI: 10.1002/ecy.2723] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 02/11/2019] [Accepted: 03/12/2019] [Indexed: 11/05/2022]
Abstract
Detrital-based trophic cascades are often considered weak or absent in tropical stream ecosystems because of the prevalence of omnivorous macroconsumers and the dearth of leaf-shredding insects. In this study, we isolate top-down effects of three macroconsumer species on detrital processing in headwater streams draining Trinidad's northern mountains. We separated effects of different macroconsumers by experimentally manipulating their temporal access to isolated benthic habitat over the diel cycle. We found no evidence that omnivorous macroconsumers, including a freshwater crab (Eudaniela garmani) and guppy (Poecilia reticulata), increased leaf decomposition via consumption. By contrast, above a waterfall excluding guppies, the insectivorous killifish, Anablepsoides hartii, reduced the biomass of the leaf-shredding insect Phylloicus hansoni 4-fold, which consequently reduced leaf decomposition rates 1.6-fold. This detrital cascade did not occur below the barrier waterfall, where omnivorous guppies join the assemblage and reduce killifish densities; here killifish had no significant effects on Phylloicus or decomposition rates. These patterns of detrital processing were also observed in upstream-downstream comparisons in a landscape study across paired reaches of six streams. Above waterfalls, where killifish were present, but guppies absent, leaf decomposition rates and Phylloicus biomass were 2.5- and ~35-fold lower, respectively, compared to measurements below waterfalls. Moreover, the strength of top-down control by killifish is reflected by the 20- and 5-fold reductions in variability (±SE) surrounding mean Phylloicus biomass and leaf decomposition rates in upstream relative to downstream reaches where no top-down control was detected. Findings show a clear, detrital-based trophic cascade among killifish, a leaf-shredding insect, and leaf decomposition rates. Results also show how omnivorous guppies disrupt this cascade by depressing killifish densities, thereby releasing invertebrate shredders from predation, and significantly increasing decomposition rates. Moreover, this combination of direct and indirect trophic interactions drives patterns in decomposition rates in stream networks at a landscape scale, resulting in significantly lower rates of decomposition above vs. below barrier waterfalls. Our findings reveal that omnivory can result in significant indirect effects on a key ecosystem process, illustrating the importance of these hidden trophic pathways in detrital-based systems and suggesting that resource control in tropical systems may be even more complex than previously envisioned.
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Affiliation(s)
- Troy N Simon
- Odum School of Ecology, University of Georgia, Athens, Georgia, 30602, USA.,Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia, 30602, USA
| | - Andrew J Binderup
- Odum School of Ecology, University of Georgia, Athens, Georgia, 30602, USA
| | - Alex S Flecker
- Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14853, USA
| | - James F Gilliam
- Department of Biology, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Michael C Marshall
- Odum School of Ecology, University of Georgia, Athens, Georgia, 30602, USA
| | - Steven A Thomas
- School of Natural Resources, University of Nebraska-Lincoln, Lincoln, Nebraska, 68583, USA
| | - Joseph Travis
- Department of Biological Science, Florida State University, Tallahassee, Florida, 32306, USA
| | - David N Reznick
- Department of Biology, University of California-Riverside, Riverside, California, 92521, USA
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Koltz AM, Classen AT, Wright JP. Warming reverses top-down effects of predators on belowground ecosystem function in Arctic tundra. Proc Natl Acad Sci U S A 2018; 115:E7541-E7549. [PMID: 30038011 PMCID: PMC6094120 DOI: 10.1073/pnas.1808754115] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Predators can disproportionately impact the structure and function of ecosystems relative to their biomass. These effects may be exacerbated under warming in ecosystems like the Arctic, where the number and diversity of predators are low and small shifts in community interactions can alter carbon cycle feedbacks. Here, we show that warming alters the effects of wolf spiders, a dominant tundra predator, on belowground litter decomposition. Specifically, while high densities of wolf spiders result in faster litter decomposition under ambient temperatures, they result, instead, in slower decomposition under warming. Higher spider densities are also associated with elevated levels of available soil nitrogen, potentially benefiting plant production. Changes in decomposition rates under increased wolf spider densities are accompanied by trends toward fewer fungivorous Collembola under ambient temperatures and more Collembola under warming, suggesting that Collembola mediate the indirect effects of wolf spiders on decomposition. The unexpected reversal of wolf spider effects on Collembola and decomposition suggest that in some cases, warming does not simply alter the strength of top-down effects but, instead, induces a different trophic cascade altogether. Our results indicate that climate change-induced effects on predators can cascade through other trophic levels, alter critical ecosystem functions, and potentially lead to climate feedbacks with important global implications. Moreover, given the expected increase in wolf spider densities with climate change, our findings suggest that the observed cascading effects of this common predator on detrital processes could potentially buffer concurrent changes in decomposition rates.
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Affiliation(s)
- Amanda M Koltz
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130;
- Department of Biology, Duke University, Durham, NC 27708
| | - Aimée T Classen
- The Rubenstein School of Environment & Natural Resources, University of Vermont, Burlington, VT 05405
- The Gund Institute for Environment, University of Vermont, Burlington, VT 05405
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Guariento RD, Luttbeg B, Carneiro LS, Caliman A. Prey adaptive behaviour under predation risk modify stoichiometry predictions of predator‐induced stress paradigms. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13089] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Barney Luttbeg
- Department of Integrative BiologyOklahoma State University Stillwater OK USA
| | | | - Adriano Caliman
- Department of EcologyFederal University of Rio Grande do Norte Natal Brazil
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7
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Fear of predation alters clone-specific performance in phloem-feeding prey. Sci Rep 2017; 7:7695. [PMID: 28794462 PMCID: PMC5550486 DOI: 10.1038/s41598-017-07723-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/17/2017] [Indexed: 11/09/2022] Open
Abstract
Fear of predation has been shown to affect prey fitness and behaviour, however, to date little is known about the underlying genetics of responses to predator-associated risk. In an effort to fill this gap we exposed four naïve clones of green peach aphid (Myzus persicae), maintained on the model crop Brassica oleracea, to different types of cues from aphid lion (Chrysoperla carnea). The respective predation risks, we termed Fear Factors, were either lethal (consumption by predator), or non-lethal (non-consumptive predator-associated cues: plant-tethered predator cadavers and homogenised shoot-sprayed or soil-infused blends of predator remains). Our results show that the non-lethal risk cues differentially impeded prey reproductive success that varied by clone, suggesting genotype-specific response to fear of predation. Furthermore, whether plants were perceived as being safe or risky influenced prey responses as avoidance behaviour in prey depended on clone type. Our findings highlight that intra-specific genetic variation underlies prey responses to consumptive and non-consumptive effects of predation. This allows selection to act on anti-predator responses to fear of predation that may ramify and influence higher trophic levels in model agroecosystems.
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Schmitz OJ, Buchkowski RW, Smith JR, Telthorst M, Rosenblatt AE. Predator community composition is linked to soil carbon retention across a human land use gradient. Ecology 2017; 98:1256-1265. [PMID: 28273334 DOI: 10.1002/ecy.1794] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/16/2017] [Accepted: 02/24/2017] [Indexed: 11/07/2022]
Abstract
Soil carbon (C) storage is a major component of the carbon cycle. Consensus holds that soil C uptake and storage is regulated by plant-microbe-soil interactions. However, the contribution of animals in aboveground food webs to this process has been overlooked. Using insights from prior long-term experimentation in an old-field ecosystem and mathematical modeling, we predicted that the amount of soil C retention within a field should increase with the proportion of active hunting predators comprising the aboveground community of active hunting and sit-and-wait predators. This comes about because predators with different hunting modes have different cascading effects on plants. Our test of the prediction revealed that the composition of the arthropod predator community and associated cascading effects on the plant community explained 41% of variation in soil C retention among 15 old fields across a human land use gradient. We also evaluated the potential for several other candidate factors to explain variation in soil C retention among fields, independent of among-field variation in the predator community. These included live plant biomass, insect herbivore community composition, soil arthropod decomposer community composition, degree of land use development around the fields, field age, and soil texture. None of these candidate variables significantly explained soil C retention among the fields. The study offers a generalizable understanding of the pathways through which arthropod predator community composition can contribute to old-field ecosystem carbon storage. This insight helps support ongoing efforts to understand and manage the effects of anthropogenic land use change on soil C storage.
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Affiliation(s)
- Oswald J Schmitz
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, Connecticut, 06511, USA
| | - Robert W Buchkowski
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, Connecticut, 06511, USA
| | - Jeffrey R Smith
- Center for Conservation Biology, Stanford University, Stanford, California, 94305, USA
| | | | - Adam E Rosenblatt
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, Connecticut, 06511, USA
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Buchkowski RW, Bradford MA, Grandy AS, Schmitz OJ, Wieder WR. Applying population and community ecology theory to advance understanding of belowground biogeochemistry. Ecol Lett 2017; 20:231-245. [DOI: 10.1111/ele.12712] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 09/27/2016] [Accepted: 11/13/2016] [Indexed: 01/26/2023]
Affiliation(s)
- Robert W. Buchkowski
- School of Forestry & Environmental Studies Yale University New Haven CT06511 USA
| | - Mark A. Bradford
- School of Forestry & Environmental Studies Yale University New Haven CT06511 USA
| | - Andrew Stuart Grandy
- Department of Natural Resources and the Environment University of New Hampshire Durham NH03824 USA
| | - Oswald J. Schmitz
- School of Forestry & Environmental Studies Yale University New Haven CT06511 USA
| | - William R. Wieder
- Climate and Global Dynamics Laboratory National Center for Atmospheric Research Boulder CO80307 USA
- Institute of Arctic and Alpine Research University of Colorado Boulder CO80309 USA
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Affiliation(s)
- A. M. Maran
- Department of Biological Sciences Bowling Green State University Bowling Green Ohio 43403 USA
| | - S. L. Pelini
- Department of Biological Sciences Bowling Green State University Bowling Green Ohio 43403 USA
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11
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Krams I, Eichler Inwood S, Trakimas G, Krams R, Burghardt GM, Butler DM, Luoto S, Krama T. Short-term exposure to predation affects body elemental composition, climbing speed and survival ability in Drosophila melanogaster. PeerJ 2016; 4:e2314. [PMID: 27602281 PMCID: PMC4991848 DOI: 10.7717/peerj.2314] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Accepted: 07/12/2016] [Indexed: 12/14/2022] Open
Abstract
Factors such as temperature, habitat, larval density, food availability and food quality substantially affect organismal development. In addition, risk of predation has a complex impact on the behavioural and morphological life history responses of prey. Responses to predation risk seem to be mediated by physiological stress, which is an adaptation for maintaining homeostasis and improving survivorship during life-threatening situations. We tested whether predator exposure during the larval phase of development has any influence on body elemental composition, energy reserves, body size, climbing speed and survival ability of adult Drosophila melanogaster. Fruit fly larvae were exposed to predation by jumping spiders (Phidippus apacheanus), and the percentage of carbon (C) and nitrogen (N) content, extracted lipids, escape response and survival were measured from predator-exposed and control adult flies. The results revealed predation as an important determinant of adult phenotype formation and survival ability. D. melanogaster reared together with spiders had a higher concentration of body N (but equal body C), a lower body mass and lipid reserves, a higher climbing speed and improved adult survival ability. The results suggest that the potential of predators to affect the development and the adult phenotype of D. melanogaster is high enough to use predators as a more natural stimulus in laboratory experiments when testing, for example, fruit fly memory and learning ability, or when comparing natural populations living under different predation pressures.
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Affiliation(s)
- Indrikis Krams
- Department of Psychology, University of Tennessee, Knoxville, United States; Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia; Department of Risk Assessment and Epidemiology, Institute of Food Safety, Animal Health and Environment BIOR, Riga, Latvia
| | - Sarah Eichler Inwood
- Bredesen Center, Energy Science and Engineering, University of Tennessee , Knoxville , United States
| | - Giedrius Trakimas
- Centre for Ecology and Environmental Research, Vilnius University, Vilnius, Lithuania; Department of Biotechnology, Daugavpils University, Daugavpils, Latvia
| | - Ronalds Krams
- Department of Biotechnology, Daugavpils University , Daugavpils , Latvia
| | - Gordon M Burghardt
- Departments of Psychology and Ecology & Evolutionary Biology, University of Tennessee , Knoxville , TN , United States
| | - David M Butler
- Department of Plant Sciences, University of Tennessee , Knoxville , United States
| | - Severi Luoto
- School of Psychology, University of Auckland, Auckland, New Zealand; English, Drama and Writing Studies, University of Auckland, Auckland, New Zealand
| | - Tatjana Krama
- Department of Plant Protection, Estonian University of Life Science , Tartu , Estonia
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12
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Sitvarin MI, Rypstra AL, Harwood JD. Linking the green and brown worlds through nonconsumptive predator effects. OIKOS 2016. [DOI: 10.1111/oik.03190] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Marino NAC, Srivastava DS, Farjalla VF. Predator kairomones change food web structure and function, regardless of cues from consumed prey. OIKOS 2015. [DOI: 10.1111/oik.02664] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Nicholas A. C. Marino
- Lab. de Limnologia, Depto de Ecologia; Inst. de Biologia, Centro de Ciências da Saúde, Univ. Federal do Rio de Janeiro; PO Box 68020 Rio de Janeiro RJ Brazil
| | - Diane S. Srivastava
- Dept of Zoology and Biodiversity Research Centre; Univ. of British Columbia; 6270 University Boulevard Vancouver BC V6T 1Z4 Canada
| | - Vinicius F. Farjalla
- Lab. de Limnologia, Depto de Ecologia; Inst. de Biologia, Centro de Ciências da Saúde, Univ. Federal do Rio de Janeiro; PO Box 68020 Rio de Janeiro RJ Brazil
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Sitvarin MI, Romanchek C, Rypstra AL. Nonconsumptive Predator-Prey Interactions: Sensitivity of the Detritivore Sinella curviseta (Collembola: Entomobryidae) to Cues of Predation Risk From the Spider Pardosa milvina (Araneae: Lycosidae). ENVIRONMENTAL ENTOMOLOGY 2015; 44:349-355. [PMID: 26313189 DOI: 10.1093/ee/nvv011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
Predators can affect prey indirectly when prey respond to cues indicating a risk of predation by altering activity levels. Changes in prey behavior may cascade through the food web to influence ecosystem function. The response of the collembolan Sinella curviseta Brook (Collembola: Entomobryidae) to cues indicating predation risk (necromones and cues from the wolf spider Pardosa milvina (Hentz) (Araneae: Lycosidae)) was tested. Additionally, necromones and predator cues were paired in a conditioning experiment to determine whether the collembolan could form learned associations. Although collembolans did not alter activity levels in response to predator cues, numerous aspects of behavior differed in the presence of necromones. There was no detectable conditioned response to predator cues after pairing with necromones. These results provide insight into how collembolans perceive and respond to predation threats that vary in information content. Previously detected indirect impacts of predator cues on ecosystem function are likely due to changes in prey other than activity level.
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Affiliation(s)
- Michael I Sitvarin
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 4054 and Department of Biology, Miami University, 700 E High St., Oxford, OH 45056. Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 40546.
| | - Christian Romanchek
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 4054 and Department of Biology, Miami University, 700 E High St., Oxford, OH 45056
| | - Ann L Rypstra
- Department of Biology, Miami University, 1601 University Blvd., Hamilton, OH 45011
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Buchkowski RW, Schmitz OJ. Detritivores ameliorate the enhancing effect of plant-based trophic cascades on nitrogen cycling in an old-field system. Biol Lett 2015; 11:20141048. [PMID: 25878045 PMCID: PMC4424612 DOI: 10.1098/rsbl.2014.1048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 03/22/2015] [Indexed: 11/12/2022] Open
Abstract
Nitrogen (N) cycling is a fundamental process central to numerous ecosystem functions and services. Accumulating evidence suggests that species within detritus- and plant-based food chains can play an instrumental role in regulating this process. However, the effects of each food chain are usually examined in isolation of each other, so it remains uncertain if their effects are equally important or if one chain exerts predominant control. We experimentally manipulated the species composition of detritus-based (isopods and spiders) and plant-based (grasshoppers and spiders) food chains individually and in combination within mesocosms containing plants and microbes from an old-field ecosystem. We tested: (i) their relative impact on N cycling, and (ii) whether interactions between them moderated the influence of one group or the other. We found that spiders in plant-based food chains exerted the only positive effect on N cycling. Detritus-based food chains had no net effects on N cycling but, when combined with plant-based food chains, ameliorated the positive effects of plant-based species. Our results suggest that detritus-based food chains may ultimately limit rates of N cycling by eroding the enhancing effects of plant-based food chains when antagonistic interactions between detritus- and plant-based species exist.
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Affiliation(s)
- Robert W Buchkowski
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven CT 06511, USA
| | - Oswald J Schmitz
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven CT 06511, USA
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