1
|
Lai HR, Bellingham PJ, McCarthy JK, Richardson SJ, Wiser SK, Stouffer DB. Detecting Nonadditive Biotic Interactions and Assessing Their Biological Relevance among Temperate Rainforest Trees. Am Nat 2024; 204:105-120. [PMID: 39008837 DOI: 10.1086/730807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
AbstractInteractions between and within abiotic and biotic processes generate nonadditive density-dependent effects on species performance that can vary in strength or direction across environments. If ignored, nonadditivities can lead to inaccurate predictions of species responses to environmental and compositional changes. While there are increasing empirical efforts to test the constancy of pairwise biotic interactions along environmental and compositional gradients, few assess both simultaneously. Using a nationwide forest inventory that spans broad ambient temperature and moisture gradients throughout New Zealand, we address this gap by analyzing the diameter growth of six focal tree species as a function of neighbor densities and climate, as well as neighbor × climate and neighbor × neighbor statistical interactions. The most complex model featuring all interaction terms had the highest predictive accuracy. Compared with climate variables, biotic interactions typically had stronger effects on diameter growth, especially when subjected to nonadditivities from local climatic conditions and the density of intermediary species. Furthermore, statistically strong (or weak) nonadditivities could be biologically irrelevant (or significant) depending on whether a species pair typically interacted under average or more extreme conditions. Our study highlights the importance of considering both the statistical potential and the biological relevance of nonadditive biotic interactions when assessing species performance under global change.
Collapse
|
2
|
Buche L, Bartomeus I, Godoy O. Multitrophic Higher-Order Interactions Modulate Species Persistence. Am Nat 2024; 203:458-472. [PMID: 38489780 DOI: 10.1086/729222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
AbstractEcologists increasingly recognize that interactions between two species can be affected by the density of a third species. How these higher-order interactions (HOIs) affect species persistence remains poorly understood. To explore the effect of HOIs stemming from multiple trophic layers on a plant community composition, we experimentally built a mesocosm with three plants and three pollinator species arranged in a fully nested and modified network structure. We estimated pairwise interactions among plants and between plants and pollinators, as well as HOIs initiated by a plant or a pollinator affecting plant species pairs. Using a structuralist approach, we evaluated the consequences of the statistically supported HOIs on the persistence probability of each of the three competing plant species and their combinations. HOIs substantially redistribute the strength and sign of pairwise interactions between plant species, promoting the opportunities for multispecies communities to persist compared with a non-HOI scenario. However, the physical elimination of a plant-pollinator link in the modified network structure promotes changes in per capita pairwise interactions and HOIs, resulting in a single-species community. Our study provides empirical evidence of the joint importance of HOIs and network structure in determining species persistence within diverse communities.
Collapse
|
3
|
Hallett LM, Aoyama L, Barabás G, Gilbert B, Larios L, Shackelford N, Werner CM, Godoy O, Ladouceur ER, Lucero JE, Weiss-Lehman CP, Chase JM, Chu C, Harpole WS, Mayfield MM, Faist AM, Shoemaker LG. Restoration ecology through the lens of coexistence theory. Trends Ecol Evol 2023; 38:1085-1096. [PMID: 37468343 DOI: 10.1016/j.tree.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 07/21/2023]
Abstract
Advances in restoration ecology are needed to guide ecological restoration in a variable and changing world. Coexistence theory provides a framework for how variability in environmental conditions and species interactions affects species success. Here, we conceptually link coexistence theory and restoration ecology. First, including low-density growth rates (LDGRs), a classic metric of coexistence, can improve abundance-based restoration goals, because abundances are sensitive to initial treatments and ongoing variability. Second, growth-rate partitioning, developed to identify coexistence mechanisms, can improve restoration practice by informing site selection and indicating necessary interventions (e.g., site amelioration or competitor removal). Finally, coexistence methods can improve restoration assessment, because initial growth rates indicate trajectories, average growth rates measure success, and growth partitioning highlights interventions needed in future.
Collapse
Affiliation(s)
- Lauren M Hallett
- Department of Biology and Environmental Studies Program, University of Oregon, Eugene, OR 97403, USA.
| | - Lina Aoyama
- Department of Biology and Environmental Studies Program, University of Oregon, Eugene, OR 97403, USA
| | - György Barabás
- Division of Ecological and Environmental Modeling (ECOMOD), Dept. IFM, Linköping University, SE-58183 Linköping, Sweden; Institute of Evolution, Centre for Ecological Research, 1121 Budapest, Hungary
| | - Benjamin Gilbert
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON M5S 3B2, Canada
| | - Loralee Larios
- Department of Botany and Plant Sciences, University of California Riverside, CA 92521, USA
| | - Nancy Shackelford
- School of Environmental Studies, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Chhaya M Werner
- University of Wyoming, Botany Department, Laramie, WY 82071, USA; Department of Environmental Science, Policy, & Sustainability, Southern Oregon University, Ashland, OR 97520, USA
| | - Oscar Godoy
- Departamento de Biología, Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, E-11510 Puerto Real, Spain
| | - Emma R Ladouceur
- Helmholtz Center for Environmental Research - UFZ, Department of Physiological Diversity, Permoserstrasse 15, 04318 Leipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv), Puschstrasse 4, 04103 Leipzig, Germany
| | - Jacob E Lucero
- Department of Rangeland, Wildlife, and Fisheries Management, Texas A&M University, College Station, TX 77843, USA
| | | | - Jonathan M Chase
- German Centre for Integrative Biodiversity Research (iDiv), Puschstrasse 4, 04103 Leipzig, Germany
| | - Chengjin Chu
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou 510275, China
| | - W Stanley Harpole
- Helmholtz Center for Environmental Research - UFZ, Department of Physiological Diversity, Permoserstrasse 15, 04318 Leipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv), Puschstrasse 4, 04103 Leipzig, Germany; Martin Luther University Halle-Wittenberg, am Kirchtor 1, 06108 Halle (Saale), Germany
| | - Margaret M Mayfield
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Akasha M Faist
- Department of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, USA; Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT 59812, USA
| | | |
Collapse
|
4
|
Granjel RR, Allan E, Godoy O. Nitrogen enrichment and foliar fungal pathogens affect the mechanisms of multispecies plant coexistence. THE NEW PHYTOLOGIST 2023; 237:2332-2346. [PMID: 36527234 DOI: 10.1111/nph.18689] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Changes in resources (e.g. nitrogen) and enemies (e.g. foliar pathogens) are key drivers of plant diversity and composition. However, their effects have not been connected to the niche and fitness differences that determine multispecies coexistence. Here, we combined a structuralist theoretical approach with a detailed grassland experiment factorially applying nitrogen addition and foliar fungal pathogen suppression to evaluate the joint effect of nitrogen and pathogens on niche and fitness differences, across a gradient from two to six interacting species. Nitrogen addition and pathogen suppression modified species interaction strengths and intrinsic growth rates, leading to reduced multispecies fitness differences. However, contrary to expected, we also observed that they promote stabilising niche differences. Although these modifications did not substantially alter species richness, they predicted major changes in community composition. Indirect interactions between species explained these community changes in smaller assemblages (three and four species) but lost importance in favour of direct pairwise interactions when more species were involved (five and six). Altogether, our work shows that explicitly considering the number of interacting species is critical for better understanding the direct and indirect processes by which nitrogen enrichment and pathogen communities shape coexistence in grasslands.
Collapse
Affiliation(s)
- Rodrigo R Granjel
- Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, 41012, Sevilla, Spain
| | - Eric Allan
- Institute of Plant Sciences, University of Bern, Alterbergrain 21, 3013, Bern, Switzerland
| | - Oscar Godoy
- Departamento de Biología, Instituto Universitario de Investigación Marina (INMAR), Universidad de Cádiz, 11510, Puerto Real, Spain
| |
Collapse
|
5
|
Paniw M, García-Callejas D, Lloret F, Bassar RD, Travis J, Godoy O. Pathways to global-change effects on biodiversity: new opportunities for dynamically forecasting demography and species interactions. Proc Biol Sci 2023; 290:20221494. [PMID: 36809806 PMCID: PMC9943645 DOI: 10.1098/rspb.2022.1494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 01/12/2023] [Indexed: 02/23/2023] Open
Abstract
In structured populations, persistence under environmental change may be particularly threatened when abiotic factors simultaneously negatively affect survival and reproduction of several life cycle stages, as opposed to a single stage. Such effects can then be exacerbated when species interactions generate reciprocal feedbacks between the demographic rates of the different species. Despite the importance of such demographic feedbacks, forecasts that account for them are limited as individual-based data on interacting species are perceived to be essential for such mechanistic forecasting-but are rarely available. Here, we first review the current shortcomings in assessing demographic feedbacks in population and community dynamics. We then present an overview of advances in statistical tools that provide an opportunity to leverage population-level data on abundances of multiple species to infer stage-specific demography. Lastly, we showcase a state-of-the-art Bayesian method to infer and project stage-specific survival and reproduction for several interacting species in a Mediterranean shrub community. This case study shows that climate change threatens populations most strongly by changing the interaction effects of conspecific and heterospecific neighbours on both juvenile and adult survival. Thus, the repurposing of multi-species abundance data for mechanistic forecasting can substantially improve our understanding of emerging threats on biodiversity.
Collapse
Affiliation(s)
- Maria Paniw
- Department of Conservation Biology and Global Change, Estación Biológica de Doñana (EBD-CSIC), Seville, 41001 Spain
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich 8057, Switzerland
| | - David García-Callejas
- Department of Integrative Ecology, Estación Biológica de Doñana (EBD-CSIC), Seville, 41001 Spain
- Instituto Universitario de Investigación Marina (INMAR), Departamento de Biología, Universidad de Cádiz, Campus Río San Pedro, 11510 Puerto Real, Spain
| | - Francisco Lloret
- Center for Ecological Research and Forestry Applications (CREAF), Cerdanyola del Vallès 08193, Spain
- Department Animal Biology, Plant Biology and Ecology, Universitat Autònoma Barcelona, Cerdanyola del Vallès 08193, Spain
| | - Ronald D. Bassar
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Joseph Travis
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA
| | - Oscar Godoy
- Instituto Universitario de Investigación Marina (INMAR), Departamento de Biología, Universidad de Cádiz, Campus Río San Pedro, 11510 Puerto Real, Spain
| |
Collapse
|
6
|
Bimler MD, Mayfield MM, Martyn TE, Stouffer DB. Estimating interaction strengths for diverse horizontal systems using performance data. Methods Ecol Evol 2023. [DOI: 10.1111/2041-210x.14068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- Malyon D. Bimler
- School of BioSciences The University of Melbourne Parkville Victoria Australia
| | | | | | - Daniel B. Stouffer
- Centre for Integrative Ecology, School of Biological Sciences University of Canterbury Christchurch New Zealand
| |
Collapse
|
7
|
Bowler CH, Shoemaker LG, Weiss‐Lehman C, Towers IR, Mayfield MM. Positive effects of exotic species dampened by neighborhood heterogeneity. Ecology 2022; 103:e3779. [PMID: 35657139 PMCID: PMC9787102 DOI: 10.1002/ecy.3779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/01/2022] [Accepted: 04/19/2022] [Indexed: 12/30/2022]
Abstract
It is well known that species interactions between exotic and native species are important for determining the success of biological invasions and how influential exotic species become in invaded communities. The strength and type of interactions between species can substantially vary, however, from negative and detrimental to minimal or even positive. Increasing evidence from the literature shows that exotic species have positive interactions with native species more often than originally thought. Gaps in our theory for how population growth is limited when interactions are positive, however, restrict our understanding of the mechanisms by which exotic "facilitators" contribute to diversity maintenance in invaded systems. Here, we quantified interactions between seven native and four exotic (established nonnative) common annual plant species in the highly diverse, York Gum woodlands of Western Australia. We used a Bayesian demographic modeling approach that allowed for interaction coefficients to be positive or negative, and explored key sources of variation in species responses to native and exotic neighbors at per capita (individual) and neighborhood levels. We observed positive per capita effects from exotic neighbors on exotic focal species as well as on several native focal species. However, all focal species were, on average, inhibited by their interaction neighborhood, when the variance in identity and abundance of observed neighbors was considered. At the neighborhood scale, exotic species were found to suppress all focal species, particularly those with high intrinsic fecundity. Our study demonstrates that within-neighborhood heterogeneity can regulate per capita positive effects of invaders, limiting runaway population growth of both natives and exotic invaders.
Collapse
Affiliation(s)
- Catherine H. Bowler
- School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
| | | | | | - Isaac R. Towers
- School of Biological, Earth and Environmental SciencesUniversity of New South WalesSydneyNew South WalesAustralia
| | | |
Collapse
|
8
|
Weiss‐Lehman CP, Werner CM, Bowler CH, Hallett L, Mayfield MM, Godoy O, Aoyama L, Barabás G, Chu C, Ladouceur E, Larios L, Shoemaker L. Disentangling key species interactions in diverse and heterogeneous communities: A Bayesian sparse modelling approach. Ecol Lett 2022; 25:1263-1276. [PMID: 35106910 PMCID: PMC9543015 DOI: 10.1111/ele.13977] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/07/2021] [Accepted: 01/02/2022] [Indexed: 11/30/2022]
Abstract
Modelling species interactions in diverse communities traditionally requires a prohibitively large number of species-interaction coefficients, especially when considering environmental dependence of parameters. We implemented Bayesian variable selection via sparsity-inducing priors on non-linear species abundance models to determine which species interactions should be retained and which can be represented as an average heterospecific interaction term, reducing the number of model parameters. We evaluated model performance using simulated communities, computing out-of-sample predictive accuracy and parameter recovery across different input sample sizes. We applied our method to a diverse empirical community, allowing us to disentangle the direct role of environmental gradients on species' intrinsic growth rates from indirect effects via competitive interactions. We also identified a few neighbouring species from the diverse community that had non-generic interactions with our focal species. This sparse modelling approach facilitates exploration of species interactions in diverse communities while maintaining a manageable number of parameters.
Collapse
Affiliation(s)
| | | | - Catherine H. Bowler
- School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
| | - Lauren M. Hallett
- Biology DepartmentUniversity of OregonEugeneOregonUSA
- Environmental Studies ProgramUniversity of OregonEugeneOregonUSA
| | - Margaret M. Mayfield
- School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
| | - Oscar Godoy
- Departamento de BiologíaInstituto Universitario de Investigación Marina (INMAR)Universidad de CádizPuerto RealSpain
| | - Lina Aoyama
- Biology DepartmentUniversity of OregonEugeneOregonUSA
- Environmental Studies ProgramUniversity of OregonEugeneOregonUSA
| | - György Barabás
- Division of Theoretical BiologyDepartment of IFMLinköping UniversityLinköpingSweden
| | - Chengjin Chu
- Department of EcologyState Key Laboratory of Biocontrol and School of Life SciencesSun Yat‐sen UniversityGuangzhouGuangdongChina
| | - Emma Ladouceur
- German Centre for Integrative Biodiversity Research (iDiv) Leipzig‐Halle‐JenaLeipzigGermany
- Department of Physiological DiversityHelmholtz Centre for Environmental Research ‐UFZLeipzigGermany
| | - Loralee Larios
- Department of Botany and Plant SciencesUniversity of California RiversideRiversideCaliforniaUSA
| | | |
Collapse
|
9
|
Lai HR, Chong KY, Yee ATK, Mayfield MM, Stouffer DB. Non-additive biotic interactions improve predictions of tropical tree growth and impact community size structure. Ecology 2021; 103:e03588. [PMID: 34797924 DOI: 10.1002/ecy.3588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 03/25/2021] [Accepted: 09/03/2021] [Indexed: 11/11/2022]
Abstract
Growth in individual size or biomass is a key demographic component in population models, with wide-ranging applications from quantifying species performance across abiotic or biotic conditions to assessing landscape-level dynamics under global change. In forest ecology, the responses of tree growth to biotic interactions are widely held to be crucial for understanding forest diversity, function, and structure. To date, most studies on plant-plant interactions only examine the additive competitive or facilitative interactions between species pairs; however, there is increasing evidence of non-additive, higher-order interactions (HOIs) impacting species demographic rates. When HOIs are present, the dynamics of a multispecies community cannot be fully understood or accurately predicted solely from pairwise outcomes because of how additional species "interfere" with the direct, pairwise interactions. Such HOIs should be particularly prevalent when species show non-linear functional responses to resource availability and resource-acquisition traits themselves are density dependent. With this in mind, we used data from a tropical secondary forest-a system that fulfills both of these conditions-to build an ontogenetic diameter growth model for individuals across 10 woody-plant species. We allowed both direct and indirect interactions within communities to influence the species-specific growth parameters in a generalized Lotka-Volterra model. Specifically, indirect interactions entered the model as higher-order quadratic terms, i.e., non-additive effects of conspecific and heterospecific neighbor size on the focal individual's growth. For the whole community and for four out of 10 focal species, the model that included HOIs had more statistical support than the model that included only direct interactions, despite the former containing a far greater number of parameters. HOIs had comparable effect sizes to direct interactions, and tended to further reduce the diameter growth rates of most species beyond what direct interactions had already reduced. In a simulation of successional stand dynamics, the inclusion of HOIs led to rank swaps in species' diameter hierarchies, even when community-level size distributions remained qualitatively similar. Our study highlights the implications, and discusses possible mechanisms, of non-additive density dependence in highly diverse and light-competitive tropical forests.
Collapse
Affiliation(s)
- Hao Ran Lai
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, 8140, New Zealand
| | - Kwek Yan Chong
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore, 117558, Singapore
| | - Alex Thiam Koon Yee
- Centre for Urban Greenery and Ecology, National Parks Board, Singapore Botanic Gardens, Singapore, Singapore
| | - Margaret M Mayfield
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, 4067, Australia
| | - Daniel B Stouffer
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, 8140, New Zealand
| |
Collapse
|