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Pashkevich MD, Luke SH, Aryawan AAK, Waters HS, Caliman J, Dupérré N, Naim M, Potapov AM, Turner EC. Riparian buffers made of mature oil palms have inconsistent impacts on oil palm ecosystems. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2552. [PMID: 35112418 PMCID: PMC9286838 DOI: 10.1002/eap.2552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 08/09/2021] [Accepted: 09/16/2021] [Indexed: 06/14/2023]
Abstract
Expansion of oil palm has caused widespread declines in biodiversity and changes in ecosystem functioning across the tropics. A major driver of these changes is loss of habitat heterogeneity as forests are converted into oil palm plantations. Therefore, one strategy to help support biodiversity and functioning in oil palm is to increase habitat heterogeneity, for instance, by retaining forested buffers around rivers when new plantations are established, or maintaining buffers made of mature oil palms ("mature palm buffers") when old plantations are replanted. While forested buffers are known to benefit oil palm systems, the impacts of mature palm buffers are less certain. In this study, we assessed the benefits of mature palm buffers, which were being passively restored (in this case, meaning that buffers were treated with no herbicides, pesticides, or fertilizers) by sampling environmental conditions and arthropods within buffers and in surrounding non-buffer areas (i.e., areas that were 25 and 125 m from buffers, and receiving normal business-as-usual management) across an 8-year chronosequence in industrial oil palm plantations (Sumatra, Indonesia). We ask (1) Do environmental conditions and biodiversity differ between buffer and non-buffer areas? (2) Do buffers affect environmental conditions and biodiversity in adjacent non-buffer areas (i.e., areas that were 25 m from buffers)? (3) Do buffers become more environmentally complex and biodiverse over time? We found that buffers can have environmental conditions (canopy openness, variation in openness, vegetation height, ground cover, and soil temperature) and levels of arthropod biodiversity (total arthropod abundance and spider abundance in the understory and spider species-level community composition in all microhabitats) that are different from those in non-buffer areas, but that these differences are inconsistent across the oil palm commercial life cycle. We also found that buffers might contribute to small increases in vegetation height and changes in ground cover in adjacent non-buffer areas, but do not increase levels of arthropod biodiversity in these areas. Finally, we found that canopy openness, variation in openness, and ground cover, but no aspects of arthropod biodiversity, change within buffers over time. Collectively, our findings indicate that mature palm buffers that are being passively restored can have greater environmental complexity and higher levels of arthropod biodiversity than non-buffer areas, particularly in comparison to recently replanted oil palm, but these benefits are not consistent across the crop commercial life cycle. If the goal of maintaining riparian buffers is to consistently increase habitat heterogeneity and improve biodiversity, an alternative to mature palm buffers or a move toward more active restoration of these areas is, therefore, probably required.
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Affiliation(s)
| | - Sarah H. Luke
- Insect Ecology Group, Department of ZoologyUniversity of CambridgeCambridgeUK
| | | | - Helen S. Waters
- Insect Ecology Group, Department of ZoologyUniversity of CambridgeCambridgeUK
- School of GeosciencesUniversity of EdinburghEdinburghUK
| | - Jean‐Pierre Caliman
- Sinar Mas Agro Resources and Technology Research Institute (SMARTRI)PekanbaruIndonesia
| | | | - Mohammad Naim
- Sinar Mas Agro Resources and Technology Research Institute (SMARTRI)PekanbaruIndonesia
| | - Anton M. Potapov
- J.F. Blumenbach Institute of Zoology and AnthropologyUniversity of GoettingenGoettingenGermany
| | - Edgar C. Turner
- Insect Ecology Group, Department of ZoologyUniversity of CambridgeCambridgeUK
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2
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Quinto J, Díaz-Castelazo C, Rico-Gray V, Martínez-Falcón AP, Abdala-Roberts L, Parra-Tabla V. Short-Term Temporal Patterns in Herbivore Beetle Assemblages in Polyculture Neotropical Forest Plantations. NEOTROPICAL ENTOMOLOGY 2022; 51:199-211. [PMID: 34988944 DOI: 10.1007/s13744-021-00933-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Although insect herbivorous communities in tropical forests are known to exhibit strong seasonality, few studies have systematically assessed temporal patterns of variation in community structure and plant-herbivore interactions in early successional arboreal communities. We assessed seasonal and interannual variation of the diversity and composition of herbivorous beetles and the tree-herbivore network in a recently established polyculture forest plantation, during the dry and the rainy seasons of 2012 and of 2013. Species richness was similar between years, while the ecological diversity was higher in 2012. Comparing seasons, no differences were found in 2012, whereas in 2013, the species richness and ecological diversity were higher during the dry season. The species composition differed radically across years and seasons. Moreover, a quantitative nested pattern was consistently found across both temporal scales, more influenced by species densities. We found temporal changes in the species strength, whereas connectance and interaction evenness remained stable. Rapid temporal changes in the structural complexity of recently established polyculture plantations and the availability and quality of the trophic resources they offer may act as drivers of beetle diversity patterns, promoting rapid variation in herbivore composition and some interacting attributes. Nonetheless, network structure, connectance, and interaction evenness remained similar, suggesting that reorganizations in the distribution of species may determine the maintenance of the patterns of interaction. Further work assessing long-term temporal dynamics of herbivore beetle assemblages are needed to more robustly relate diversity and interaction patterns to biotic and abiotic factors and their implications in management programs.
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Affiliation(s)
- Javier Quinto
- Departamento de Ecología Tropical, Universidad Autónoma de Yucatán (UADY), Mérida, Yucatan, Mexico.
- Instituto de Investigación y Formación Agraria y Pesquera de Andalucía (IFAPA), Centro de Málaga (Churriana), Málaga, Spain.
| | | | - Víctor Rico-Gray
- Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Veracruz, Mexico
| | - Ana Paola Martínez-Falcón
- Laboratorio de Ecología de Comunidades, Centro de Investigaciones Biológicas, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Mineral de La Reforma, Hidalgo, Mexico
| | - Luis Abdala-Roberts
- Departamento de Ecología Tropical, Universidad Autónoma de Yucatán (UADY), Mérida, Yucatan, Mexico
| | - Víctor Parra-Tabla
- Departamento de Ecología Tropical, Universidad Autónoma de Yucatán (UADY), Mérida, Yucatan, Mexico
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3
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Bongers FJ, Schmid B, Durka W, Li S, Bruelheide H, Hahn CZ, Yan H, Ma K, Liu X. Genetic richness affects trait variation but not community productivity in a tree diversity experiment. THE NEW PHYTOLOGIST 2020; 227:744-756. [PMID: 32242938 DOI: 10.1111/nph.16567] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
Biodiversity-ecosystem functioning experiments found that productivity generally increases with species richness, but less is known about effects of within-species genetic richness and potential interactions between the two. While functional differences between species can explain species richness effects, empirical evidence regarding functional differences between genotypes within species and potential consequences for productivity is largely lacking. We therefore measured within- and among-species variation in functional traits and growth and determined stand-level tree biomass in a large forest experiment factorially manipulating species and genetic richness in subtropical China. Within-species variation across genetic seed families, in addition to variation across species, explained a substantial amount of trait variation. Furthermore, trait responses to species and genetic richness varied significantly within and between species. Multivariate trait variation was larger among individuals from species mixtures than those from species monocultures, but similar among individuals from genetically diverse vs genetically uniform monocultures. Correspondingly, species but not genetic richness had a positive effect on stand-level tree biomass. We argue that identifying functional diversity within and among species in forest communities is necessary to separate effects of species and genetic diversity on tree growth and community productivity.
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Affiliation(s)
- Franca J Bongers
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
| | - Bernhard Schmid
- Department of Geography, University of Zurich, 8057, Zurich, Switzerland
| | - Walter Durka
- Department of Community Ecology, UFZ - Helmholtz Centre for Environmental Research, Theodor-Lieser-Str. 4, 06120, Halle, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany
| | - Shan Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
| | - Helge Bruelheide
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany
- Institute of Biology, Martin Luther University Halle-Wittenberg, D-06108, Halle, Germany
| | - Christoph Z Hahn
- Department of Community Ecology, UFZ - Helmholtz Centre for Environmental Research, Theodor-Lieser-Str. 4, 06120, Halle, Germany
- Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Haoru Yan
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Keping Ma
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
| | - Xiaojuan Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
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Solís-Montero V, Martínez-Natarén DA, Parra-Tabla V, Ibarra-Cerdeña C, Munguía-Rosas MA. Herbivory and anti-herbivore defences in wild and cultivated Cnidoscolus aconitifolius: disentangling domestication and environmental effects. AOB PLANTS 2020; 12:plaa023. [PMID: 32607138 PMCID: PMC7306974 DOI: 10.1093/aobpla/plaa023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/29/2020] [Indexed: 05/20/2023]
Abstract
Phenotypic changes in plants during domestication may disrupt plant-herbivore interactions. Because wild and cultivated plants have different habitats and some anti-herbivore defences exhibit some plasticity, their defences may be also influenced by the environment. Our goal was to assess the effects of domestication and the environment on herbivory and some anti-herbivore defences in chaya (Cnidoscolus aconitifolius) in its centre of domestication. Herbivores, herbivory, and direct and indirect anti-herbivore defences were assessed in wild and cultivated plants. The same variables were measured in the field and in a common garden to assess environmental effects. Our results show that domestication increased herbivory and herbivore abundance, but reduced direct and some indirect defences (ants). The environment also affected the herbivore guild (herbivore abundance and richness) and some direct and indirect defences (trichome number and ants). There was also an interaction effect of domestication and the environment on the number of trichomes. We conclude that domestication and the environment influence herbivory and anti-herbivore defences in an additive and interactive manner in chaya.
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Affiliation(s)
- Virginia Solís-Montero
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Merida C.P., México
| | - Daniela A Martínez-Natarén
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Merida C.P., México
- Consejo Nacional de Ciencia y Tecnología (Conacyt), Insurgentes Sur, Ciudad de México C.P., México
| | - Víctor Parra-Tabla
- Departamento de Ecología Tropical, Universidad Autónoma de Yucatán, Merida C.P., México
| | - Carlos Ibarra-Cerdeña
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Merida C.P., México
| | - Miguel A Munguía-Rosas
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Merida C.P., México
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Barantal S, Castagneyrol B, Durka W, Iason G, Morath S, Koricheva J. Contrasting effects of tree species and genetic diversity on the leaf-miner communities associated with silver birch. Oecologia 2019; 189:687-697. [PMID: 30799514 PMCID: PMC6418074 DOI: 10.1007/s00442-019-04351-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 01/30/2019] [Indexed: 11/29/2022]
Abstract
Both species and genetic diversity of plant communities can affect insect herbivores, but a few studies have compared the effects of both diversity levels within the same experimental context. We compared the effects of tree species and genetic diversity on abundance, species richness, and β-diversity of leaf-miner communities associated with silver birch using two long-term forest diversity experiments in Finland where birch trees were planted in monocultures and mixtures of birch genotypes or other trees species. Although both abundance and species richness of leaf miners differed among birch genotypes at the tree level, birch genetic diversity had no significant effect on miner abundance and species richness at the plot level. Instead, birch genetic diversity affected leaf-miner β-diversity with species turnover being higher among trees within genotypic mixtures than among trees within monoclonal plots. In contrast, tree species diversity had a significant negative effect on both leaf-miner abundance and species richness at plot level, but no effect on miner β-diversity. Significant tree species diversity effects on leaf-miner abundance and species richness were found only in plots with high tree density. We have demonstrated that plant species and genetic diversity play important but contrasting roles in structuring associated herbivore communities. Tree species diversity largely affects miner abundance and species richness, whereas tree genetic diversity affects miner β-diversity. These results have important implications for conservation and management of woodlands.
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Affiliation(s)
- Sandra Barantal
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK. .,Ecotron-CNRS, 1 Chemin du Rioux, 34980, Monferrier, France.
| | | | - Walter Durka
- Helmholtz Centre for Environmental Research-UFZ, 06120, Halle, Germany
| | - Glenn Iason
- James Hutton Institute, Aberdeen, AB15 8QH, UK
| | - Simon Morath
- Forest Research, Alice Holt Lodge, Farnham, Surrey, GU10 4LH, UK
| | - Julia Koricheva
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK
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6
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Raffard A, Santoul F, Cucherousset J, Blanchet S. The community and ecosystem consequences of intraspecific diversity: a meta-analysis. Biol Rev Camb Philos Soc 2018; 94:648-661. [PMID: 30294844 DOI: 10.1111/brv.12472] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 09/12/2018] [Accepted: 09/14/2018] [Indexed: 12/12/2022]
Abstract
Understanding the relationships between biodiversity and ecosystem functioning has major implications. Biodiversity-ecosystem functioning relationships are generally investigated at the interspecific level, although intraspecific diversity (i.e. within-species diversity) is increasingly perceived as an important ecological facet of biodiversity. Here, we provide a quantitative and integrative synthesis testing, across diverse plant and animal species, whether intraspecific diversity is a major driver of community dynamics and ecosystem functioning. We specifically tested (i) whether the number of genotypes/phenotypes (i.e. intraspecific richness) or the specific identity of genotypes/phenotypes (i.e. intraspecific variation) in populations modulate the structure of communities and the functioning of ecosystems, (ii) whether the ecological effects of intraspecific richness and variation are strong in magnitude, and (iii) whether these effects vary among taxonomic groups and ecological responses. We found a non-linear relationship between intraspecific richness and community and ecosystem dynamics that follows a saturating curve shape, as observed for biodiversity-function relationships measured at the interspecific level. Importantly, intraspecific richness modulated ecological dynamics with a magnitude that was equal to that previously reported for interspecific richness. Our results further confirm, based on a database containing more than 50 species, that intraspecific variation also has substantial effects on ecological dynamics. We demonstrated that the effects of intraspecific variation are twice as high as expected by chance, and that they might have been underestimated previously. Finally, we found that the ecological effects of intraspecific variation are not homogeneous and are actually stronger when intraspecific variation is manipulated in primary producers than in consumer species, and when they are measured at the ecosystem rather than at the community level. Overall, we demonstrated that the two facets of intraspecific diversity (richness and variation) can both strongly affect community and ecosystem dynamics, which reveals the pivotal role of within-species biodiversity for understanding ecological dynamics.
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Affiliation(s)
- Allan Raffard
- CNRS, Station d'Écologie Théorique et Expérimentale du CNRS à Moulis UMR-5321, Université Toulouse III Paul Sabatier, 2 route du CNRS, F-09200, Moulis, France.,EcoLab, Université de Toulouse, CNRS, INPT, UPS, 31062 Toulouse, France
| | - Frédéric Santoul
- EcoLab, Université de Toulouse, CNRS, INPT, UPS, 31062 Toulouse, France
| | - Julien Cucherousset
- CNRS, IRD, UPS, Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, 118 route de Narbonne, Toulouse 31062, France
| | - Simon Blanchet
- CNRS, Station d'Écologie Théorique et Expérimentale du CNRS à Moulis UMR-5321, Université Toulouse III Paul Sabatier, 2 route du CNRS, F-09200, Moulis, France.,CNRS, IRD, UPS, Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, 118 route de Narbonne, Toulouse 31062, France
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7
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Cao HX, Klein AM, Zhu C, Staab M, Durka W, Fischer M, Fornoff F. Intra- and interspecific tree diversity promotes multitrophic plant–Hemiptera–ant interactions in a forest diversity experiment. Basic Appl Ecol 2018. [DOI: 10.1016/j.baae.2018.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Koricheva J, Hayes D. The relative importance of plant intraspecific diversity in structuring arthropod communities: A meta‐analysis. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13062] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Julia Koricheva
- School of Biological SciencesRoyal Holloway University of London Egham Surrey UK
| | - Dexter Hayes
- School of Biological SciencesRoyal Holloway University of London Egham Surrey UK
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Fischer DG, Wimp GM, Hersch‐Green E, Bangert RK, LeRoy CJ, Bailey JK, Schweitzer JA, Dirks C, Hart SC, Allan GJ, Whitham TG. Tree genetics strongly affect forest productivity, but intraspecific diversity–productivity relationships do not. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12733] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dylan G. Fischer
- The Evergreen State College 2700 Evergreen Parkway NW Olympia WA98505 USA
| | - Gina M. Wimp
- Biology Department Georgetown University Reiss Science Building, 37th and O Streets NW Washington DC20057 USA
| | - Erika Hersch‐Green
- Department of Biological Sciences Michigan Technological University 1400 Townsend Drive Houghton MI49931‐1295 USA
| | - Randy K. Bangert
- Department of Biological Sciences Northern Arizona University PO Box 5460 Flagstaff AZ86001 USA
- School of Earth Sciences and Environmental Sustainability Northern Arizona University PO Box 5694 Flagstaff AZ86011 USA
| | - Carri J. LeRoy
- The Evergreen State College 2700 Evergreen Parkway NW Olympia WA98505 USA
| | - Joseph K. Bailey
- Department of Ecology and Evolutionary Biology University of Tennessee 569 Dabney Hall Knoxville TN37996 USA
| | - Jennifer A. Schweitzer
- Department of Ecology and Evolutionary Biology University of Tennessee 569 Dabney Hall Knoxville TN37996 USA
| | - Clarissa Dirks
- The Evergreen State College 2700 Evergreen Parkway NW Olympia WA98505 USA
| | - Stephen C. Hart
- Life & Environmental Sciences and Sierra Nevada Research Institute University of California Merced CA95344 USA
| | - Gerard J. Allan
- Department of Biological Sciences Northern Arizona University PO Box 5460 Flagstaff AZ86001 USA
| | - Thomas G. Whitham
- Department of Biological Sciences Northern Arizona University PO Box 5460 Flagstaff AZ86001 USA
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Esquivel-Gómez L, Abdala-Roberts L, Pinkus-Rendón M, Parra-Tabla V. Effects of tree species diversity on a community of weaver spiders in a tropical forest plantation. Biotropica 2016. [DOI: 10.1111/btp.12352] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luis Esquivel-Gómez
- Departamento de Ecología Tropical; Campus de Ciencias Biológicas y Agropecuarias; Universidad Autόnoma de Yucatán; Apartado Postal 4-116, Itzimná Merida 97000 Yucatan Mexico
| | - Luis Abdala-Roberts
- Departamento de Ecología Tropical; Campus de Ciencias Biológicas y Agropecuarias; Universidad Autόnoma de Yucatán; Apartado Postal 4-116, Itzimná Merida 97000 Yucatan Mexico
| | - Miguel Pinkus-Rendón
- Centro Peninsular en Humanidades y Ciencias Sociales; Universidad Nacional Autónoma de México; Merida 97150 Yucatan Mexico
| | - Víctor Parra-Tabla
- Departamento de Ecología Tropical; Campus de Ciencias Biológicas y Agropecuarias; Universidad Autόnoma de Yucatán; Apartado Postal 4-116, Itzimná Merida 97000 Yucatan Mexico
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11
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Campos-Navarrete MJ, Abdala-Roberts L, Munguía-Rosas MA, Parra-Tabla V. Are Tree Species Diversity and Genotypic Diversity Effects on Insect Herbivores Mediated by Ants? PLoS One 2015; 10:e0132671. [PMID: 26241962 PMCID: PMC4524695 DOI: 10.1371/journal.pone.0132671] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 06/17/2015] [Indexed: 11/18/2022] Open
Abstract
Plant diversity can influence predators and omnivores and such effects may in turn influence herbivores and plants. However, evidence for these ecological feedbacks is rare. We evaluated if the effects of tree species (SD) and genotypic diversity (GD) on the abundance of different guilds of insect herbivores associated with big-leaf mahogany (Swietenia macrophylla) were contingent upon the protective effects of ants tending extra-floral nectaries of this species. This study was conducted within a larger experiment consisting of mahogany monocultures and species polycultures of four species and –within each of these two plot types– mahogany was represented by either one or four maternal families. We selected 24 plots spanning these treatment combinations, 10 mahogany plants/plot, and within each plot experimentally reduced ant abundance on half of the selected plants, and surveyed ant and herbivore abundance. There were positive effects of SD on generalist leaf-chewers and sap-feeders, but for the latter group this effect depended on the ant reduction treatment: SD positively influenced sap-feeders under ambient ant abundance but had no effect when ant abundance was reduced; at the same time, ants had negative effects on sap feeders in monoculture but no effect in polyculture. In contrast, SD did not influence specialist stem-borers or leaf-miners and this effect was not contingent upon ant reduction. Finally, GD did not influence any of the herbivore guilds studied, and such effects did not depend on the ant treatment. Overall, we show that tree species diversity influenced interactions between a focal plant species (mahogany) and ants, and that such effects in turn mediated plant diversity effects on some (sap-feeders) but not all the herbivores guilds studied. Our results suggest that the observed patterns are dependent on the combined effects of herbivore identity, diet breadth, and the source of plant diversity.
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Affiliation(s)
- María José Campos-Navarrete
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autόnoma de Yucatán, Apartado Postal 4–116, Itzimná, 97000, Mérida, Yucatán, México
| | - Luis Abdala-Roberts
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autόnoma de Yucatán, Apartado Postal 4–116, Itzimná, 97000, Mérida, Yucatán, México
| | - Miguel A. Munguía-Rosas
- Departamento de Ecología Humana, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), KM 6 Antigua Carretera a Progreso, Mérida, 97310, México
| | - Víctor Parra-Tabla
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autόnoma de Yucatán, Apartado Postal 4–116, Itzimná, 97000, Mérida, Yucatán, México
- * E-mail:
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