A. Dairain, Manon Doutrelant, Sarah Bureau, Sébastien Henry, Olivier Maire
While parasitism is a common lifestyle on Earth, its importance for the functioning of marine ecosystems has been overlooked for a long time. In particular, parasites have significant potential to influence central ecological processes through their impacts on hosts that serve as ecosystem engineers. Using an ex situ experimental approach, we explored the effects of trematode parasites on the engineering bioturbation activity of a common and abundant bivalve along European Atlantic soft‐bottom coastlines, the peppery furrow shell Scrobicularia plana, as well as knock‐on effects for nutrient exchanges at the sediment–water interface (SWI). Trematodes negatively impacted the host's ability to transport sediment particles and solutes in a density‐dependent way, with parasite burden explaining 22–31% of the inter‐individual variability. This could be explained by parasitism impairing the bivalve physiological state and ability to burrow, as we observed a decrease in the condition index and the burrowing depth of the bivalves with an increase in the number of parasites they host. In contrast, the influence of S. plana on benthic biogeochemical fluxes did not vary significantly according to parasitic burden over a short time scale. Here, we focused on the effects of trematode parasites on the behaviour of S. plana alone, and thus excluded other macrofaunal organisms. We should next test whether trematodes modulate the structure and functioning of benthic communities dominated by S. plana to better understand and quantify the engineering role of parasites in soft‐bottom coastal environments.
{"title":"Density‐dependent effects of parasitism on the activity of a benthic engineer species: potential impact on ecosystem functioning","authors":"A. Dairain, Manon Doutrelant, Sarah Bureau, Sébastien Henry, Olivier Maire","doi":"10.1111/oik.10400","DOIUrl":"https://doi.org/10.1111/oik.10400","url":null,"abstract":"While parasitism is a common lifestyle on Earth, its importance for the functioning of marine ecosystems has been overlooked for a long time. In particular, parasites have significant potential to influence central ecological processes through their impacts on hosts that serve as ecosystem engineers. Using an ex situ experimental approach, we explored the effects of trematode parasites on the engineering bioturbation activity of a common and abundant bivalve along European Atlantic soft‐bottom coastlines, the peppery furrow shell Scrobicularia plana, as well as knock‐on effects for nutrient exchanges at the sediment–water interface (SWI). Trematodes negatively impacted the host's ability to transport sediment particles and solutes in a density‐dependent way, with parasite burden explaining 22–31% of the inter‐individual variability. This could be explained by parasitism impairing the bivalve physiological state and ability to burrow, as we observed a decrease in the condition index and the burrowing depth of the bivalves with an increase in the number of parasites they host. In contrast, the influence of S. plana on benthic biogeochemical fluxes did not vary significantly according to parasitic burden over a short time scale. Here, we focused on the effects of trematode parasites on the behaviour of S. plana alone, and thus excluded other macrofaunal organisms. We should next test whether trematodes modulate the structure and functioning of benthic communities dominated by S. plana to better understand and quantify the engineering role of parasites in soft‐bottom coastal environments.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139792495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Communities that are farther away from one another in distance or time tend to be more dissimilar. These relationships are often referred to as ‘distance–decay' relationships, relating compositional dissimilarity of communities to geographic distance or exploring compositional shifts through time at a single site. The data required to explore both relationships simultaneously – and their potential interactions – require standardized sampling through time across a set of geographically unique sites. We used data on five taxonomic groups sampled between 2013 and 2021 as part of the National Ecological Observatory Network (NEON) to explore evidence for geographic and temporal distance–decay relationships. Links between these relationships were explored by estimating the temporal consistency of geographic distance–decay relationships and estimating the strength of geographic patterns in temporal distance–decay relationships. Overall, we found evidence for geographic and temporal distance–decay relationships across the five studied taxa, but detected no temporal signal in geographic distance–decay relationships and no spatial signal in temporal distance–decay relationships. Together, this highlights that community composition changes across geographic and temporal gradients, but that the drivers of these changes may depend on different drivers at different scales.
{"title":"Geographic and temporal distance–decay relationships across taxa","authors":"Tad A. Dallas, Lauren A. Holian, Cleber Ten Caten","doi":"10.1111/oik.10269","DOIUrl":"https://doi.org/10.1111/oik.10269","url":null,"abstract":"Communities that are farther away from one another in distance or time tend to be more dissimilar. These relationships are often referred to as ‘distance–decay' relationships, relating compositional dissimilarity of communities to geographic distance or exploring compositional shifts through time at a single site. The data required to explore both relationships simultaneously – and their potential interactions – require standardized sampling through time across a set of geographically unique sites. We used data on five taxonomic groups sampled between 2013 and 2021 as part of the National Ecological Observatory Network (NEON) to explore evidence for geographic and temporal distance–decay relationships. Links between these relationships were explored by estimating the temporal consistency of geographic distance–decay relationships and estimating the strength of geographic patterns in temporal distance–decay relationships. Overall, we found evidence for geographic and temporal distance–decay relationships across the five studied taxa, but detected no temporal signal in geographic distance–decay relationships and no spatial signal in temporal distance–decay relationships. Together, this highlights that community composition changes across geographic and temporal gradients, but that the drivers of these changes may depend on different drivers at different scales.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139765753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Dairain, Manon Doutrelant, Sarah Bureau, Sébastien Henry, Olivier Maire
While parasitism is a common lifestyle on Earth, its importance for the functioning of marine ecosystems has been overlooked for a long time. In particular, parasites have significant potential to influence central ecological processes through their impacts on hosts that serve as ecosystem engineers. Using an ex situ experimental approach, we explored the effects of trematode parasites on the engineering bioturbation activity of a common and abundant bivalve along European Atlantic soft‐bottom coastlines, the peppery furrow shell Scrobicularia plana, as well as knock‐on effects for nutrient exchanges at the sediment–water interface (SWI). Trematodes negatively impacted the host's ability to transport sediment particles and solutes in a density‐dependent way, with parasite burden explaining 22–31% of the inter‐individual variability. This could be explained by parasitism impairing the bivalve physiological state and ability to burrow, as we observed a decrease in the condition index and the burrowing depth of the bivalves with an increase in the number of parasites they host. In contrast, the influence of S. plana on benthic biogeochemical fluxes did not vary significantly according to parasitic burden over a short time scale. Here, we focused on the effects of trematode parasites on the behaviour of S. plana alone, and thus excluded other macrofaunal organisms. We should next test whether trematodes modulate the structure and functioning of benthic communities dominated by S. plana to better understand and quantify the engineering role of parasites in soft‐bottom coastal environments.
{"title":"Density‐dependent effects of parasitism on the activity of a benthic engineer species: potential impact on ecosystem functioning","authors":"A. Dairain, Manon Doutrelant, Sarah Bureau, Sébastien Henry, Olivier Maire","doi":"10.1111/oik.10400","DOIUrl":"https://doi.org/10.1111/oik.10400","url":null,"abstract":"While parasitism is a common lifestyle on Earth, its importance for the functioning of marine ecosystems has been overlooked for a long time. In particular, parasites have significant potential to influence central ecological processes through their impacts on hosts that serve as ecosystem engineers. Using an ex situ experimental approach, we explored the effects of trematode parasites on the engineering bioturbation activity of a common and abundant bivalve along European Atlantic soft‐bottom coastlines, the peppery furrow shell Scrobicularia plana, as well as knock‐on effects for nutrient exchanges at the sediment–water interface (SWI). Trematodes negatively impacted the host's ability to transport sediment particles and solutes in a density‐dependent way, with parasite burden explaining 22–31% of the inter‐individual variability. This could be explained by parasitism impairing the bivalve physiological state and ability to burrow, as we observed a decrease in the condition index and the burrowing depth of the bivalves with an increase in the number of parasites they host. In contrast, the influence of S. plana on benthic biogeochemical fluxes did not vary significantly according to parasitic burden over a short time scale. Here, we focused on the effects of trematode parasites on the behaviour of S. plana alone, and thus excluded other macrofaunal organisms. We should next test whether trematodes modulate the structure and functioning of benthic communities dominated by S. plana to better understand and quantify the engineering role of parasites in soft‐bottom coastal environments.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139852277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Priscila S. Oliveira, Luiz A. D. Falcão, Jarcilene S. Almeida, Geraldo Wilson Fernandes, Ronaldo Reis Júnior, Yule R. F. Nunes, Maria das Dores M. Veloso, Marina do Vale Beirão, Frederico de Siqueira Neves, Ricardo R. C. Solar, Magno A. Z. Borges, Alex C. Silva, Renato P. Salomão, Luciana Iannuzzi, Luciana F. Silva, George A. L. Cabral, Everardo V. S. B. Sampaio, Luiz E. Macedo-Reis, Cleandson F. Santos, Solange M. Kerpel, Rayana M. Souza, Iaciara G. S. Cardoso, Mário M. do Espírito Santo
Evaluating the diversity of multiple taxa is fundamental to understand community assembly and to assess the integrity and functionality of tropical secondary forests. In this study, we analyzed the natural regeneration of tropical dry forests (TDFs) in three regions of Brazil using Hill–Simpson diversity, abundance and β-diversity of trees and five groups of insects (herbivores, fruit-feeding butterflies, ants, culicid mosquitoes and dung beetles). Sampling was conducted in 39 0.1 ha plots using a chronosequence approach (13 plots in early, intermediate and old-growth forests). We evaluated the contribution of three different levels to γ-diversity: α (within plots), β1 (among plots) and β2 (among successional stages), and further determined the relative importance of turnover (species replacement) and nestedness (differences in species number among sites) to β2. Our results showed that, unexpectedly, the Hill–Simpson diversity was consistently higher in early than old-growth stages for all regions, but varied more widely in the intermediate stages. For each group separately, the same trend was observed for butterflies, ants, dung beetles and herbivores and did not differ among stages for mosquitoes. Successional differences in abundance were only detected for trees (increasing along the gradient) and for mosquitoes (decreasing). According to our expectations, the additive partitioning analysis showed that β2-diversity contributed more to γ-diversity than β1-diversity, when all taxa were considered together and for most of them separately (except for butterflies and dung beetles). Most of the β2-diversity was due to species turnover, but this contribution varied among groups and regions, with the highest turnover for herbivores and the lowest for dung beetles. Our results suggest that the Hill–Simpson diversity and changes in species composition (as given by β2-diversity) are better indicators of forest natural regeneration than raw species richness, corroborating previous studies with plants and animals.
{"title":"Diversity patterns along ecological succession in tropical dry forests: a multi-taxonomic approach","authors":"Priscila S. Oliveira, Luiz A. D. Falcão, Jarcilene S. Almeida, Geraldo Wilson Fernandes, Ronaldo Reis Júnior, Yule R. F. Nunes, Maria das Dores M. Veloso, Marina do Vale Beirão, Frederico de Siqueira Neves, Ricardo R. C. Solar, Magno A. Z. Borges, Alex C. Silva, Renato P. Salomão, Luciana Iannuzzi, Luciana F. Silva, George A. L. Cabral, Everardo V. S. B. Sampaio, Luiz E. Macedo-Reis, Cleandson F. Santos, Solange M. Kerpel, Rayana M. Souza, Iaciara G. S. Cardoso, Mário M. do Espírito Santo","doi":"10.1111/oik.09653","DOIUrl":"https://doi.org/10.1111/oik.09653","url":null,"abstract":"Evaluating the diversity of multiple taxa is fundamental to understand community assembly and to assess the integrity and functionality of tropical secondary forests. In this study, we analyzed the natural regeneration of tropical dry forests (TDFs) in three regions of Brazil using Hill–Simpson diversity, abundance and β-diversity of trees and five groups of insects (herbivores, fruit-feeding butterflies, ants, culicid mosquitoes and dung beetles). Sampling was conducted in 39 0.1 ha plots using a chronosequence approach (13 plots in early, intermediate and old-growth forests). We evaluated the contribution of three different levels to γ-diversity: α (within plots), β<sup>1</sup> (among plots) and β<sup>2</sup> (among successional stages), and further determined the relative importance of turnover (species replacement) and nestedness (differences in species number among sites) to β<sup>2</sup>. Our results showed that, unexpectedly, the Hill–Simpson diversity was consistently higher in early than old-growth stages for all regions, but varied more widely in the intermediate stages. For each group separately, the same trend was observed for butterflies, ants, dung beetles and herbivores and did not differ among stages for mosquitoes. Successional differences in abundance were only detected for trees (increasing along the gradient) and for mosquitoes (decreasing). According to our expectations, the additive partitioning analysis showed that β<sup>2</sup>-diversity contributed more to γ-diversity than β<sup>1</sup>-diversity, when all taxa were considered together and for most of them separately (except for butterflies and dung beetles). Most of the β<sup>2</sup>-diversity was due to species turnover, but this contribution varied among groups and regions, with the highest turnover for herbivores and the lowest for dung beetles. Our results suggest that the Hill–Simpson diversity and changes in species composition (as given by β<sup>2</sup>-diversity) are better indicators of forest natural regeneration than raw species richness, corroborating previous studies with plants and animals.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139767052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cristian S. Dambros, Thiago Junqueira Izzo, Luciene Castuera de Oliveira, Ricardo Eduardo Vicente, Carlos A. Peres
Agricultural expansion has markedly reduced forests and reconfigured landscapes. These changes incur a well-known detrimental impact on the biodiversity of local forest patches, but the effects on species persistence in entire landscapes comprised of multiple patches are debated. Using data from ants collected in the Amazonian deforestation arc in Brazil, we investigated how regional diversity is affected by habitat loss, fragmentation, and cattle grazing, and how species respond to deforestation both locally and regionally. We also investigated how the heterogeneity in species distribution (beta-diversity) buffers landscapes against local diversity losses. We used hierarchical multi-species occupancy models to estimate these effects while controlling for errors in species detection. The vast majority of the 251 ant species found in our study were negatively affected by both habitat loss and cattle at local forest patches, drastically reducing diversity at these patches compared to continuous forests. Despite local declines in diversity, however, heavily fragmented landscapes could still retain most species due to the high heterogeneity in species distribution. We found that beta-diversity is the main component of regional diversity. Results from several studies suggest that this component is maximized when remnant primary habitats in a landscape are spread across vast areas. Although preserving local diversity may be important for the adequate functioning of the ecosystem locally, our results indicate that the maintenance of many small forest patches in a landscape can buffer regional biodiversity against local species losses. Our results suggest that even small forest remnants in otherwise deforested landscapes can collectively prevent most regional-scale species extirpations, and therefore also merit conservation efforts.
{"title":"Beta-diversity buffers fragmented landscapes against local species losses","authors":"Cristian S. Dambros, Thiago Junqueira Izzo, Luciene Castuera de Oliveira, Ricardo Eduardo Vicente, Carlos A. Peres","doi":"10.1111/oik.10401","DOIUrl":"https://doi.org/10.1111/oik.10401","url":null,"abstract":"Agricultural expansion has markedly reduced forests and reconfigured landscapes. These changes incur a well-known detrimental impact on the biodiversity of local forest patches, but the effects on species persistence in entire landscapes comprised of multiple patches are debated. Using data from ants collected in the Amazonian deforestation arc in Brazil, we investigated how regional diversity is affected by habitat loss, fragmentation, and cattle grazing, and how species respond to deforestation both locally and regionally. We also investigated how the heterogeneity in species distribution (beta-diversity) buffers landscapes against local diversity losses. We used hierarchical multi-species occupancy models to estimate these effects while controlling for errors in species detection. The vast majority of the 251 ant species found in our study were negatively affected by both habitat loss and cattle at local forest patches, drastically reducing diversity at these patches compared to continuous forests. Despite local declines in diversity, however, heavily fragmented landscapes could still retain most species due to the high heterogeneity in species distribution. We found that beta-diversity is the main component of regional diversity. Results from several studies suggest that this component is maximized when remnant primary habitats in a landscape are spread across vast areas. Although preserving local diversity may be important for the adequate functioning of the ecosystem locally, our results indicate that the maintenance of many small forest patches in a landscape can buffer regional biodiversity against local species losses. Our results suggest that even small forest remnants in otherwise deforested landscapes can collectively prevent most regional-scale species extirpations, and therefore also merit conservation efforts.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139559322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ines Klemme, Tommi Perälä, Sami O. Lehtinen, Anna Kuparinen
Parasites commonly alter the phenotype of their hosts, thereby influencing competitive and consumer–resource interactions. This could trigger a cascade effect on the dynamics of biological communities, but the role of parasites in ecosystem processes is poorly understood. In this study, we investigate how parasite-induced trait modifications shape the dynamics of a complex lake food web using an allometric trophic network model (ATN). We simulated infections of stage-structured fish host populations via increased maintenance costs and predation risk. Our results show that host trait modifications can significantly impact host demography, with stage-specific biomass declines up to 60%. However, less severely affected host stages buffered these effects and sustained the population. Importantly, host biomass decline altered the dynamics of species interactions and these effects cascaded through the entire community, with biomass changes observed at all trophic levels. Our findings emphasize the importance of incorporating both indirect parasite effects and host life history in ecological network studies for more realistic simulations of community dynamics.
{"title":"Parasite-mediated changes in host traits alter food web dynamics","authors":"Ines Klemme, Tommi Perälä, Sami O. Lehtinen, Anna Kuparinen","doi":"10.1111/oik.10374","DOIUrl":"https://doi.org/10.1111/oik.10374","url":null,"abstract":"Parasites commonly alter the phenotype of their hosts, thereby influencing competitive and consumer–resource interactions. This could trigger a cascade effect on the dynamics of biological communities, but the role of parasites in ecosystem processes is poorly understood. In this study, we investigate how parasite-induced trait modifications shape the dynamics of a complex lake food web using an allometric trophic network model (ATN). We simulated infections of stage-structured fish host populations via increased maintenance costs and predation risk. Our results show that host trait modifications can significantly impact host demography, with stage-specific biomass declines up to 60%. However, less severely affected host stages buffered these effects and sustained the population. Importantly, host biomass decline altered the dynamics of species interactions and these effects cascaded through the entire community, with biomass changes observed at all trophic levels. Our findings emphasize the importance of incorporating both indirect parasite effects and host life history in ecological network studies for more realistic simulations of community dynamics.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139559324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuval R. Zelnik, Matthieu Barbier, David W. Shanafelt, Michel Loreau, Rachel M. Germain
Ecology is a science of scale, which guides our description of both ecological processes and patterns, but we lack a systematic understanding of how process scale and pattern scale are connected. Recent calls for synthesis between population ecology, community ecology, and ecosystem ecology motivate the integration of phenomena at multiple organizational levels. Furthermore, many studies leave out the scaling of a critical process: species interactions, which may be non-local through movement or foraging and must be distinguished from dispersal scales. Here, we use simulations to explore the consequences of three different process scales (species interactions, dispersal, and the environment) on emergent patterns of biodiversity, ecosystem functioning, and their relationship, in a spatially-explicit landscape and stable equilibrium setting. A major result of our study is that the spatial scales of dispersal and species interactions have opposite effects: a larger dispersal scale homogenizes spatial biomass patterns, while a larger interaction scale amplifies their heterogeneity. Interestingly, the specific scale at which dispersal and interaction scales begin to influence landscape patterns depends on the scale of environmental heterogeneity – in other words, the scale of one process allows important scales to emerge in other processes. This interplay between process scales, i.e. a situation where no single process dominates, can only occur when the environment is heterogeneous and the scale of dispersal small. Finally, contrary to our expectations, we observe that the spatial scale of ecological processes is more clearly reflected in landscape patterns (i.e. distribution of local outcomes) than in global patterns such as species–area relationships (SARs) or large-scale biodiversity–functioning relationships. Overall we conclude that long-range interactions often act differently and even in opposite ways to dispersal, and that the landscape patterns that emerge from the interplay of long-ranged interactions, dispersal and environmental heterogeneity are not well captured by often-used metrics like the SAR.
{"title":"Linking intrinsic scales of ecological processes to characteristic scales of biodiversity and functioning patterns","authors":"Yuval R. Zelnik, Matthieu Barbier, David W. Shanafelt, Michel Loreau, Rachel M. Germain","doi":"10.1111/oik.10514","DOIUrl":"https://doi.org/10.1111/oik.10514","url":null,"abstract":"Ecology is a science of scale, which guides our description of both ecological processes and patterns, but we lack a systematic understanding of how process scale and pattern scale are connected. Recent calls for synthesis between population ecology, community ecology, and ecosystem ecology motivate the integration of phenomena at multiple organizational levels. Furthermore, many studies leave out the scaling of a critical process: species interactions, which may be non-local through movement or foraging and must be distinguished from dispersal scales. Here, we use simulations to explore the consequences of three different process scales (species interactions, dispersal, and the environment) on emergent patterns of biodiversity, ecosystem functioning, and their relationship, in a spatially-explicit landscape and stable equilibrium setting. A major result of our study is that the spatial scales of dispersal and species interactions have opposite effects: a larger dispersal scale homogenizes spatial biomass patterns, while a larger interaction scale amplifies their heterogeneity. Interestingly, the specific scale at which dispersal and interaction scales begin to influence landscape patterns depends on the scale of environmental heterogeneity – in other words, the scale of one process allows important scales to emerge in other processes. This interplay between process scales, i.e. a situation where no single process dominates, can only occur when the environment is heterogeneous and the scale of dispersal small. Finally, contrary to our expectations, we observe that the spatial scale of ecological processes is more clearly reflected in landscape patterns (i.e. distribution of local outcomes) than in global patterns such as species–area relationships (SARs) or large-scale biodiversity–functioning relationships. Overall we conclude that long-range interactions often act differently and even in opposite ways to dispersal, and that the landscape patterns that emerge from the interplay of long-ranged interactions, dispersal and environmental heterogeneity are not well captured by often-used metrics like the SAR.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139516636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phillip J. Haubrock, Ismael Soto, Melina Kourantidou, Danish A. Ahmed, Ali Serhan Tarkan, Paride Balzani, Kristi Bego, Antonín Kouba, Sadi Aksu, Elizabeta Briski, Francisco Sylvester, Vanessa De Santis, Gaït Archambaud-Suard, Núria Bonada, Miguel Cañedo-Argüelles, Zoltán Csabai, Thibault Datry, Mathieu Floury, Jean-François Fruget, John Iwan Jones, Marie-Helene Lizee, Anthony Maire, John F. Murphy, Davis Ozolins, Jes Jessen Rasmussen, Agnija Skuja, Gábor Várbíró, Piet Verdonschot, Ralf C. M. Verdonschot, Peter Wiberg-Larsen, Ross N. Cuthbert
The zebra mussel Dreissena polymorpha is one of the most successful, notorious, and detrimental aquatic invasive non-native species worldwide, having invaded Europe and North America while causing substantial ecological and socio-economic impacts. Here, we investigated the spatiotemporal trends in this species' invasion success using 178 macroinvertebrate abundance time series, containing 1451 records of D. polymorpha collected across nine European countries between 1972–2019. Using these raw (absolute) abundance data, we examined trends and drivers of occurrences and relative abundances of D. polymorpha within invaded communities. Meta-regression models revealed non-significant trends both at the European level and for the majority of the invaded countries, except for France (significant decreasing trend) and Hungary (marginally positive trend). At the European level, the number of D. polymorpha occurrences over time followed a flat-top bell-shaped distribution, with a steep increase between 1973–1989 followed by a plateau phase prior to significantly declining post-1998. Using a series of climatic and hydromorphological site-specific characteristics of invaded and uninvaded sites from two periods (1998–2002; 2011–2015), we found that native richness, non-native abundance, distance to the next barrier, and elevation were associated with the occurrence of D. polymorpha. We also found that higher native richness and lower latitude were related to lower relative abundances. Using Cohen's D as a measure of D. polymorpha impact, we found that biodiversity within the invaded sites was initially higher than in uninvaded ones, but then declined, suggesting differences in biodiversity trends across invaded and uninvaded sites. While our results emphasise the high invasion success of D. polymorpha, increasing stressors within the context of global change – particularly ongoing climate change – are likely to enhance invasion rates and the impact of D. polymorpha in the near future, exacerbated by the lack of timely and effective management actions.
斑马贻贝(Dreissena polymorpha)是世界上最成功、最臭名昭著、危害最大的水生入侵非本地物种之一,在入侵欧洲和北美的同时对生态和社会经济造成了巨大影响。在此,我们利用 178 个大型无脊椎动物丰度时间序列研究了该物种入侵成功的时空趋势,这些时间序列包含 1972-2019 年间在 9 个欧洲国家收集的 1451 条 D. polymorpha 记录。利用这些原始(绝对)丰度数据,我们研究了被入侵群落中多甲虫的出现趋势和驱动因素以及相对丰度。元回归模型显示,除法国(显著下降趋势)和匈牙利(略呈正趋势)外,欧洲层面和大多数受入侵国家的趋势都不显著。在欧洲层面,D. polymorpha 的出现数量随着时间的推移呈平顶钟形分布,1973-1989 年间急剧上升,随后进入高原阶段,1998 年后显著下降。利用两个时期(1998-2002 年;2011-2015 年)入侵和未入侵地点的一系列气候和水文地质特征,我们发现本地丰富度、非本地丰富度、到下一个障碍物的距离和海拔与多甲藻的出现有关。我们还发现,较高的本地丰富度和较低的纬度与较低的相对丰度有关。使用科恩氏 D 作为 D. polymorpha 影响的衡量标准,我们发现受入侵地点的生物多样性最初高于未受入侵地点,但随后有所下降,这表明受入侵地点和未受入侵地点的生物多样性趋势存在差异。虽然我们的研究结果表明多甲藻的入侵成功率很高,但在全球变化(尤其是持续的气候变化)的背景下,越来越多的压力因素可能会在不久的将来提高多甲藻的入侵率和影响,而缺乏及时有效的管理措施则会加剧这种情况。
{"title":"Understanding the complex dynamics of zebra mussel invasions over several decades in European rivers: drivers, impacts and predictions","authors":"Phillip J. Haubrock, Ismael Soto, Melina Kourantidou, Danish A. Ahmed, Ali Serhan Tarkan, Paride Balzani, Kristi Bego, Antonín Kouba, Sadi Aksu, Elizabeta Briski, Francisco Sylvester, Vanessa De Santis, Gaït Archambaud-Suard, Núria Bonada, Miguel Cañedo-Argüelles, Zoltán Csabai, Thibault Datry, Mathieu Floury, Jean-François Fruget, John Iwan Jones, Marie-Helene Lizee, Anthony Maire, John F. Murphy, Davis Ozolins, Jes Jessen Rasmussen, Agnija Skuja, Gábor Várbíró, Piet Verdonschot, Ralf C. M. Verdonschot, Peter Wiberg-Larsen, Ross N. Cuthbert","doi":"10.1111/oik.10283","DOIUrl":"https://doi.org/10.1111/oik.10283","url":null,"abstract":"The zebra mussel <i>Dreissena polymorpha</i> is one of the most successful, notorious, and detrimental aquatic invasive non-native species worldwide, having invaded Europe and North America while causing substantial ecological and socio-economic impacts. Here, we investigated the spatiotemporal trends in this species' invasion success using 178 macroinvertebrate abundance time series, containing 1451 records of <i>D. polymorpha</i> collected across nine European countries between 1972–2019. Using these raw (absolute) abundance data, we examined trends and drivers of occurrences and relative abundances of <i>D. polymorpha</i> within invaded communities. Meta-regression models revealed non-significant trends both at the European level and for the majority of the invaded countries, except for France (significant decreasing trend) and Hungary (marginally positive trend). At the European level, the number of <i>D. polymorpha</i> occurrences over time followed a flat-top bell-shaped distribution, with a steep increase between 1973–1989 followed by a plateau phase prior to significantly declining post-1998. Using a series of climatic and hydromorphological site-specific characteristics of invaded and uninvaded sites from two periods (1998–2002; 2011–2015), we found that native richness, non-native abundance, distance to the next barrier, and elevation were associated with the occurrence of <i>D. polymorpha</i>. We also found that higher native richness and lower latitude were related to lower relative abundances. Using Cohen's D as a measure of <i>D. polymorpha</i> impact, we found that biodiversity within the invaded sites was initially higher than in uninvaded ones, but then declined, suggesting differences in biodiversity trends across invaded and uninvaded sites. While our results emphasise the high invasion success of <i>D. polymorpha</i>, increasing stressors within the context of global change – particularly ongoing climate change – are likely to enhance invasion rates and the impact of <i>D. polymorpha</i> in the near future, exacerbated by the lack of timely and effective management actions.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139516237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Loïc Prosnier, Nicolas Loeuille, Florence D. Hulot, David Renault, Christophe Piscart, Baptiste Bicocchi, Muriel Deparis, Matthieu Lam, Vincent Médoc
Parasites are omnipresent, and their eco-evolutionary significance has aroused much interest from scientists. Parasites may affect their hosts in many ways with changes in density, appearance, behaviour and energy content, likely to modify their value to predators (profitability) within the optimal foraging framework. Consequently, parasites could impact predators' diet and the trophic links through food webs. Here, we investigate the consequences of the infection by the iridovirus Daphnia iridescent virus 1 (DIV-1) on the reproductive success, mortality, appearance, mobility, and biochemical composition of water fleas Daphnia magna, a widespread freshwater crustacean. We do predation tests and compare search time, handling time and feeding preference between infected and uninfected Daphnia when preyed upon by Notonecta sp., a common aquatic insect. Our findings show that infection does not change fecundity but reduces lifespan and thereby constrains fitness. Infected Daphnia show reduced mobility and increased color reflectance in the UV and visible domains, which potentially affects their appearance and thus vulnerability to predators. Infection increases body size and the amount of proteins but does not affect carbohydrate and lipid contents. Although infected Daphnia are longer to handle, they are preferred over uninfected individuals by aquatic insects. Taken together, our findings show that DIV-1 infection could make Daphnia more profitable to predators (24% energy increase), a positive effect that should be balanced with a lower availability due to the higher mortality of infected specimens. We also highlight that exposure to infection in asymptomatic individuals leads to ecological characteristics that differ from both healthy and symptomatic infected individuals.
{"title":"Parasites make hosts more profitable but less available to predators","authors":"Loïc Prosnier, Nicolas Loeuille, Florence D. Hulot, David Renault, Christophe Piscart, Baptiste Bicocchi, Muriel Deparis, Matthieu Lam, Vincent Médoc","doi":"10.1111/oik.10469","DOIUrl":"https://doi.org/10.1111/oik.10469","url":null,"abstract":"Parasites are omnipresent, and their eco-evolutionary significance has aroused much interest from scientists. Parasites may affect their hosts in many ways with changes in density, appearance, behaviour and energy content, likely to modify their value to predators (profitability) within the optimal foraging framework. Consequently, parasites could impact predators' diet and the trophic links through food webs. Here, we investigate the consequences of the infection by the iridovirus Daphnia iridescent virus 1 (DIV-1) on the reproductive success, mortality, appearance, mobility, and biochemical composition of water fleas <i>Daphnia magna</i>, a widespread freshwater crustacean. We do predation tests and compare search time, handling time and feeding preference between infected and uninfected <i>Daphnia</i> when preyed upon by <i>Notonecta</i> sp., a common aquatic insect. Our findings show that infection does not change fecundity but reduces lifespan and thereby constrains fitness. Infected <i>Daphnia</i> show reduced mobility and increased color reflectance in the UV and visible domains, which potentially affects their appearance and thus vulnerability to predators. Infection increases body size and the amount of proteins but does not affect carbohydrate and lipid contents. Although infected <i>Daphnia</i> are longer to handle, they are preferred over uninfected individuals by aquatic insects. Taken together, our findings show that DIV-1 infection could make <i>Daphnia</i> more profitable to predators (24% energy increase), a positive effect that should be balanced with a lower availability due to the higher mortality of infected specimens. We also highlight that exposure to infection in asymptomatic individuals leads to ecological characteristics that differ from both healthy and symptomatic infected individuals.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139516279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
β-diversity patterns (the compositional variations across sites) and their drivers are the major concerns of biodiversity research and conservation practices, whereas such information remains scarce for vascular epiphytes, especially in tropical forest communities. This study aimed to reveal the pattern and driving process of the compositional variations of vascular epiphytes in a tropical cloud forest on Hainan island, southern China, and their differences from those of terrestrial woody plants. To this end, we quantified their between-habitat compositional variations and distinguished the underlying components of β-diversity (nestedness and turnover). We then examined the relative roles of niche-based and neutral processes in driving the compositional variations by using a null model approach. Our results showed that the between-habitat compositional variations were significant for both plant assemblages and stronger in vascular epiphytes than in terrestrial woody plants. The turnover component of β-diversity was significantly stronger in terrestrial woody plants, accounting for 73.16–80.08% of the variations. By contrast, the nestedness component was significantly stronger in vascular epiphytes and characterized 46.82–67.5% of the variations. Besides, the compositional variations of both plant assemblages, especially terrestrial woody plants, were generally poorly fitted by the simulated niche-based scenarios but well fitted by the simulated neutral scenarios. Overall, the compositional variations of both plant assemblages were significant and mainly due to dispersal limitation, albeit to varying degrees. Hence, further studies of these plant assemblages at local scales should not be ideologically limited to the niche-based framework. Moreover, the stronger nestedness observed in vascular epiphytes suggests the greater importance of prioritizing conservation efforts in the species-rich habitats for these plants.
{"title":"Pattern and driver of the compositional variations in a tropical cloud forest: comparing vascular epiphytes with terrestrial woody plants","authors":"Chuchu Xiao, Guang Feng, Wenxing Long","doi":"10.1111/oik.10158","DOIUrl":"https://doi.org/10.1111/oik.10158","url":null,"abstract":"β-diversity patterns (the compositional variations across sites) and their drivers are the major concerns of biodiversity research and conservation practices, whereas such information remains scarce for vascular epiphytes, especially in tropical forest communities. This study aimed to reveal the pattern and driving process of the compositional variations of vascular epiphytes in a tropical cloud forest on Hainan island, southern China, and their differences from those of terrestrial woody plants. To this end, we quantified their between-habitat compositional variations and distinguished the underlying components of β-diversity (nestedness and turnover). We then examined the relative roles of niche-based and neutral processes in driving the compositional variations by using a null model approach. Our results showed that the between-habitat compositional variations were significant for both plant assemblages and stronger in vascular epiphytes than in terrestrial woody plants. The turnover component of β-diversity was significantly stronger in terrestrial woody plants, accounting for 73.16–80.08% of the variations. By contrast, the nestedness component was significantly stronger in vascular epiphytes and characterized 46.82–67.5% of the variations. Besides, the compositional variations of both plant assemblages, especially terrestrial woody plants, were generally poorly fitted by the simulated niche-based scenarios but well fitted by the simulated neutral scenarios. Overall, the compositional variations of both plant assemblages were significant and mainly due to dispersal limitation, albeit to varying degrees. Hence, further studies of these plant assemblages at local scales should not be ideologically limited to the niche-based framework. Moreover, the stronger nestedness observed in vascular epiphytes suggests the greater importance of prioritizing conservation efforts in the species-rich habitats for these plants.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139497176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}