Ryan B. Stephens, Andrew P. Ouimette, Erik A. Hobbie, Rebecca J. Rowe
{"title":"Reevaluating trophic discrimination factors (Δδ13C and Δδ15N) for diet reconstruction","authors":"Ryan B. Stephens, Andrew P. Ouimette, Erik A. Hobbie, Rebecca J. Rowe","doi":"10.1002/ecm.1525","DOIUrl":"10.1002/ecm.1525","url":null,"abstract":"<p>Stable isotope analysis is increasingly being used to assess diet and trophic positions of animals. Such assessments require estimates of trophic discrimination factors (TDFs)—offset between the isotopic composition of diet and animal tissues—with imprecise applications of TDFs leading to biased conclusions in resource use. Because TDFs are unavailable for most species, ecologists often apply values from taxonomically similar species or use trophic step increases of approximately 1‰ for carbon (TDF-δ<sup>13</sup>C) and 3‰ for nitrogen (TDF-δ<sup>15</sup>N). Such practices may yield inaccuracies since TDFs vary greatly, even within a species. To better understand the factors that influence TDFs, we conducted a meta-analysis of TDF-δ<sup>13</sup>C and TDF-δ<sup>15</sup>N for mammals and quantified variation in relation to consumer type (herbivore, omnivore, carnivore) and diet source (C<sub>3</sub>-based, C<sub>4</sub>-based, marine-based, mixture). Additionally, to guide TDF choice, we used an isotopic data set of small mammal tissues and diet items to assess how predicted dietary contributions vary with TDFs estimated using (1) taxonomic relatedness, (2) consumer type and diet source, or (3) values derived from wild animals eating natural diets. Our meta-analysis revealed that metabolic routing and interactions between consumer class, dietary source, and the protein versus energy content of diets best explained variation in TDF-δ<sup>13</sup>C values (−1.5‰ to 7.3‰), whereas consumer class best explained variation in TDF-δ<sup>15</sup>N values (−0.5‰ to 7.1‰). Our test of methods to estimate TDFs indicated that ecologists should avoid relying on taxonomic relatedness when selecting TDF-δ<sup>13</sup>C because mixed-diet lab studies may produce misleading results for herbivores and omnivores. Additionally, field-derived estimates could help fill TDF gaps where diets within a consumer class are absent. Overall, we suggest that using standard TDF trophic step values should be abandoned, because feeding studies are often poor proxies for natural diets, particularly for herbivores and omnivores. Instead, we make recommendations on how to select TDFs, along with a range of TDF-δ<sup>13</sup>C and TDF-δ<sup>15</sup>N values depending on diet source, consumer class, and tissue type. Use of these more refined recommendations and TDF values in isotopic assessments will improve estimates of diets and trophic interactions in natural systems, leading to a better understanding of ecological interactions and communities.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48175808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Ruijiao Sun, Christophe Barbraud, Henri Weimerskirch, Karine Delord, Samantha C. Patrick, Hal Caswell, Stephanie Jenouvrier
{"title":"Causes and consequences of pair-bond disruption in a sex-skewed population of a long-lived monogamous seabird","authors":"Ruijiao Sun, Christophe Barbraud, Henri Weimerskirch, Karine Delord, Samantha C. Patrick, Hal Caswell, Stephanie Jenouvrier","doi":"10.1002/ecm.1522","DOIUrl":"10.1002/ecm.1522","url":null,"abstract":"<p>Many animals form long-term monogamous pair bonds, and the disruption of a pair bond (through either divorce or widowhood) can have significant consequences for individual vital rates (survival, breeding, and breeding success probabilities) and life-history outcomes (lifetime reproductive success [LRS], life expectancy). Here, we investigated the causes and consequences of pair-bond disruption in wandering albatross (<i>Diomedea exulans</i>). State-of-the-art statistical and mathematical approaches were developed to estimate divorce and widowhood rates and their impacts on vital rates and life-history outcomes. In this population, females incur a higher mortality rate due to incidental fishery bycatch, so the population is male-skewed. Therefore, we first posited that males would show higher widowhood rates negatively correlated with fishing effort and females would have higher divorce rates because they have more mating opportunities. Furthermore, we expected that divorce could be an adaptive strategy, whereby individuals improved breeding success by breeding with a new partner of better quality. Finally, we posited that pair-bond disruptions could reduce survival and breeding probabilities owing to the cost of remating processes, with important consequences for life-history outcomes. As expected, we showed that males had higher widowhood rates than females and females had higher divorce rates in this male-skewed population. However, no correlation was found between fishing effort and male widowhood. Secondly, contrary to our expectation, we found that divorce was likely nonadaptive in this population. We propose that divorce in this population is caused by an intruder who outcompetes the original partner in line with the so-called forced divorce hypothesis. Furthermore, we found a 16.7% and 18.0% reduction in LRS only for divorced and widowed males, respectively, owing to missing breeding seasons after a pair-bond disruption. Finally, we found that divorced individuals were more likely to divorce again, but whether this is related to specific individual characteristics remains an important area of investigation.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/02/12/ECM-92-e1522.PMC9539511.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33544140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Ionescu, M. Bizic, R. Karnatak, C. L. Musseau, G. Onandia, M. Kasada, S. A. Berger, J. C. Nejstgaard, M. Ryo, G. Lischeid, M. O. Gessner, S. Wollrab, H.-P. Grossart
{"title":"From microbes to mammals: Pond biodiversity homogenization across different land-use types in an agricultural landscape","authors":"D. Ionescu, M. Bizic, R. Karnatak, C. L. Musseau, G. Onandia, M. Kasada, S. A. Berger, J. C. Nejstgaard, M. Ryo, G. Lischeid, M. O. Gessner, S. Wollrab, H.-P. Grossart","doi":"10.1002/ecm.1523","DOIUrl":"https://doi.org/10.1002/ecm.1523","url":null,"abstract":"<p>Local biodiversity patterns are expected to strongly reflect variation in topography, land use, dispersal boundaries, nutrient supplies, contaminant spread, management practices, and other anthropogenic influences. Contrary to this expectation, studies focusing on specific taxa revealed a biodiversity homogenization effect in areas subjected to long-term intensive industrial agriculture. We investigated whether land use affects biodiversity levels and community composition (α- and β-diversity) in 67 kettle holes (KH) representing small aquatic islands embedded in the patchwork matrix of a largely agricultural landscape comprising grassland, forest, and arable fields. These KH, similar to millions of standing water bodies of glacial origin, spread across northern Europe, Asia, and North America, are physico-chemically diverse and differ in the degree of coupling with their surroundings. We assessed aquatic and sediment biodiversity patterns of eukaryotes, <i>Bacteria</i>, and <i>Archaea</i> in relation to environmental features of the KH, using deep-amplicon-sequencing of environmental DNA (eDNA). First, we asked whether deep sequencing of eDNA provides a representative picture of KH aquatic biodiversity across the <i>Bacteria</i>, <i>Archaea</i>, and eukaryotes. Second, we investigated if and to what extent KH biodiversity is influenced by the surrounding land use. We hypothesized that richness and community composition will greatly differ in KH from agricultural land use compared with KH in grasslands and forests. Our data show that deep eDNA amplicon sequencing is useful for in-depth assessments of cross-domain biodiversity comprising both micro- and macro-organisms, but has limitations with respect to single-taxa conservation studies. Using this broad method, we show that sediment eDNA, integrating several years to decades, depicts the history of agricultural land-use intensification. Aquatic biodiversity was best explained by seasonality, whereas land-use type explained little of the variation. We concluded that, counter to our hypothesis, land use intensification coupled with landscape wide nutrient enrichment (including atmospheric deposition), groundwater connectivity between KH and organismal (active and passive) dispersal in the tight network of ponds, resulted in a biodiversity homogenization in the KH water, leveling off today's detectable differences in KH biodiversity between land-use types. These findings have profound implications for measures and management strategies to combat current biodiversity loss in agricultural landscapes worldwide.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecm.1523","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138016195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seraina L. Cappelli, Noémie A. Pichon, Tosca Mannall, Eric Allan
{"title":"Partitioning the effects of plant diversity on ecosystem functions at different trophic levels","authors":"Seraina L. Cappelli, Noémie A. Pichon, Tosca Mannall, Eric Allan","doi":"10.1002/ecm.1521","DOIUrl":"10.1002/ecm.1521","url":null,"abstract":"<p>Biodiversity effects on ecosystem functioning can be partitioned into complementarity effects, driven by many species, and selection effects, driven by few. Selection effects occur through interspecific abundance shifts (dominance) and intraspecific shifts in functioning. Complementarity and selection effects are often calculated for biomass, but very rarely for secondary productivity, that is, energy transfer to higher trophic levels. We calculated diversity effects for three functions: aboveground biomass, insect herbivory and pathogen infection, the latter two as proxies for energy transfer to higher trophic levels, in a grassland experiment (PaNDiv) manipulating species richness, functional composition, nitrogen enrichment, and fungicide treatment. Complementarity effects were, on average, positive and selection effects negative for biomass production and pathogen infection and multiple species contributed to diversity effects in mixtures. Diversity effects were, on average, less pronounced for herbivory. Diversity effects for the three functions were not correlated, because different species drove the different effects. Benefits (and costs) from growing in diverse communities, be it reduced herbivore or pathogen damage or increased productivity either due to abundance increases or increased productivity per area were distributed across different plant species, leading to highly variable contributions of single species to effects of diversity on different functions. These results show that different underlying ecological mechanisms can result in similar overall diversity effects across functions.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecm.1521","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46157255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matthew D. Green, Kurt E. Anderson, David B. Herbst, Marko J. Spasojevic
{"title":"Rethinking biodiversity patterns and processes in stream ecosystems","authors":"Matthew D. Green, Kurt E. Anderson, David B. Herbst, Marko J. Spasojevic","doi":"10.1002/ecm.1520","DOIUrl":"10.1002/ecm.1520","url":null,"abstract":"<p>A major goal of community ecology is understanding the processes responsible for generating biodiversity patterns along spatial and environmental gradients. In stream ecosystems, system-specific conceptual frameworks have dominated research describing biodiversity change along longitudinal gradients of river networks. However, support for these conceptual frameworks has been mixed, mainly applicable to specific stream ecosystems and biomes, and these frameworks have placed less emphasis on general mechanisms driving biodiversity patterns. Rethinking biodiversity patterns and processes in stream ecosystems with a focus on the overarching mechanisms common across ecosystems will provide a more holistic understanding of why biodiversity patterns vary along river networks. In this study, we apply the theory of ecological communities (TEC) conceptual framework to stream ecosystems to focus explicitly on the core ecological processes structuring communities: dispersal, speciation, niche selection, and ecological drift. Using a unique case study from high-elevation networks of connected lakes and streams, we sampled stream invertebrate communities in the Sierra Nevada, California, USA to test established stream ecology frameworks and compared them with the TEC framework. Local diversity increased and β-diversity decreased moving downstream from the headwaters, consistent with the river continuum concept and the small but mighty framework of mountain stream biodiversity. Local diversity was also structured by distance below upstream lakes, where diversity increased with distance below upstream lakes, in support of the serial discontinuity concept. Despite some support for the biodiversity patterns predicted from the stream ecology frameworks, no single framework was fully supported, suggesting “context dependence.” By framing our results under the TEC, we found that species diversity was structured by niche selection, where local diversity was highest in environmentally favorable sites. Local diversity was also highest in sites with small community sizes, countering the predicted effects of ecological drift. Moreover, higher β-diversity in the headwaters was influenced by dispersal and niche selection, where environmentally harsh and spatially isolated sites exhibit higher community variation. Taken together our results suggest that combining system-specific ecological frameworks with the TEC provides a powerful approach for inferring the mechanisms driving biodiversity patterns and provides a path toward generalization of biodiversity research across ecosystems.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48708305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
E. Payne, O. Spiegel, D. L. Sinn, S. T. Leu, M. G. Gardner, S. S. Godfrey, C. Wohlfeil, A. Sih
{"title":"Intrinsic traits, social context, and local environment shape home range size and fidelity of sleepy lizards","authors":"E. Payne, O. Spiegel, D. L. Sinn, S. T. Leu, M. G. Gardner, S. S. Godfrey, C. Wohlfeil, A. Sih","doi":"10.1002/ecm.1519","DOIUrl":"10.1002/ecm.1519","url":null,"abstract":"<p>Home ranges (HRs), the regions within which animals interact with their environment, constitute a fundamental aspect of their ecology. HR sizes and locations commonly reflect costs and benefits associated with diverse social, biotic, and abiotic factors. Less is known, however, about how these factors affect intraspecific variation in HR size or fidelity (the individual's tendency to maintain the same HR location over time) or whether variation in these features emerge from consistent differences among individuals or among the sites they occupy. To address this knowledge gap, we used an extensive GPS-tracking data set of a long-lived lizard, the sleepy lizard (<i>Tiliqua rugosa</i>), which included repeated observations of multiple individuals across years. We tested how three categories of predictors—(1) lizard characteristics (sex, aggressiveness, and parasitic tick counts), (2) environmental characteristics (precipitation, food, and refuge quality), and (3) social conditions (conspecific overlap and number of neighbors)—affected HR size and fidelity. We found that individuals differed consistently in the size and fidelity of annual HRs (with a repeatability of 0.58 and 0.33, respectively), and that all three categories of predictors affected both HR size and fidelity. For example, HRs were smaller in areas with more food, and males had larger HRs than females. In addition, more aggressive lizards tended to have larger HRs. Conspecific overlap and number of individuals that a lizard interacted with (social network degree) had an interactive effect on HR size where individuals whose HRs overlapped more with neighbors had larger HRs, and this effect was particularly strong for individuals that interacted with more neighbors. HR fidelity declined over time (HR locations drifted from year to year), but individuals differed consistently in this rate of drift. The fact that HR size was consistent despite drifting locations suggests that lizard HRs reflect individual traits (e.g., habitat choice criteria that differ among individuals), rather than simple heterogeneity among sites. Overall, these findings demonstrate (1) both strong, long-term, within-individual consistency and between-individual differences in space use and (2) combined effects of individual traits, social conditions, and environmental characteristics on animal HRs, with implications for diverse ecological processes.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45727369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Daniel R. Garrett, Fanie Pelletier, Dany Garant, Marc Bélisle
{"title":"Combined influence of food availability and agricultural intensification on a declining aerial insectivore","authors":"Daniel R. Garrett, Fanie Pelletier, Dany Garant, Marc Bélisle","doi":"10.1002/ecm.1518","DOIUrl":"https://doi.org/10.1002/ecm.1518","url":null,"abstract":"<p>Aerial insectivores show worldwide population declines coinciding with shifts in agricultural practices. Increasing reliance on certain agricultural practices is thought to have led to an overall reduction in insect abundance that negatively affects aerial insectivore fitness. The relationship between prey availability and the fitness of insectivores may thus vary with the extent of agricultural intensity. It is therefore imperative to quantify the strength and direction of these associations. Here we used data from an 11-year study monitoring the breeding of Tree Swallows (<i>Tachycineta bicolor</i>) and the availability of Diptera (their main prey) across a gradient of agricultural intensification in southern Québec, Canada. This gradient was characterized by a shift in agricultural production, whereby landscapes composed of forage and pastures represented less agro-intensive landscapes and those focusing on large-scale arable row crop monocultures, such as corn (<i>Zea mays</i>) or soybean (<i>Glycine max</i>) that are innately associated with significant mechanization and agro-chemical inputs, represented more agro-intensive landscapes. We evaluated the landscape characteristics affecting prey availability and how this relationship influences the fledging success, duration of the nestling period, fledgling body mass, and wing length as these variables are known to influence the population dynamics of this species. Diptera availability was greatest within predominately forested landscapes, while within landscapes dominated by agriculture, it was marginally greater in less agro-intensive areas. Of the measured fitness and body condition proxies, both fledging success and nestling body mass were positively related to prey availability. The impact of prey availability varied across the agricultural gradient as fledging success improved with increasing prey levels within forage landscapes yet declined in more agro-intensive landscapes. Finally, after accounting for prey availability, fledging success was lowest, nestling periods were the longest, and wing length of fledglings were shortest within more agro-intensive landscapes. Our results highlight the interacting roles that aerial insect availability and agricultural intensification have on the fitness of aerial insectivores, and by extension how food availability may interact with other aspects of breeding habitats to influence the population dynamics of predators.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137955911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
David J. S. Montagnes, Qing Wang, Zhao Lyu, Chen Shao
{"title":"Evaluating thermal performance of closely related taxa: Support for hotter is not better, but for unexpected reasons","authors":"David J. S. Montagnes, Qing Wang, Zhao Lyu, Chen Shao","doi":"10.1002/ecm.1517","DOIUrl":"10.1002/ecm.1517","url":null,"abstract":"<p>Temperature drives performance and therefore adaptation; to interpret and understand these, thermal performance curves (TPC) are used, often through meta-analyses, revealing trends across divergent taxa. Four discrete hypotheses—thermodynamic-constraint; biochemical-adaptation (hotter is not better); specialist-generalist; thermal-trade-off—have arisen to explain cross-phyletic trends. In contrast, detailed comparisons of closely related taxa are rare, yet trends arising from these should reveal mechanisms of adaptation, as taxa diverge. Here, we combine experimental work with TPC theory to assess if the current hypotheses apply equally to closely related taxa. We established TPC for six species (and two strains of one species) of the animal model <i>Tetrahymena</i> (Ciliophora)—characterized by SSU rDNA/COX1 sequences—by examining specific growth rate (<i>r</i>), size (<i>V</i>), production (<i>P</i> = <i>rV</i>), and metabolic rate (<i>rV</i><sup>−0.25</sup>) across 15–20 temperatures. Using parameters derived from the mechanistic “Sharpe and DeMichele” function, we established a framework to test which hypothesis best represented the data. We conclude that superficially the “hotter is not better” hypothesis is best but argue that the mechanistic theory underlying it cannot apply at the genus level: trends are likely to arise from little rather than substantial adaptation. Our further analysis suggests: (1) upward shift in the maximum-functioning temperature (<i>T</i><sub>max</sub>) is more constrained than the optimal temperature (<i>T</i><sub>opt</sub>), leading to a decreased safety margin (<i>T</i><sub>opt</sub>−<i>T</i><sub>max</sub>) and suggesting that species initially succeed in warmer environments through an increase in <i>T</i><sub>opt</sub>, followed by increasing <i>T</i><sub>max</sub>; and (2) thermal performance traits are correlated with phylogeny for closely related species, suggesting that species gradually adapt to new thermal environments.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecm.1517","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46329360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Janne S. Koskinen, Nerea Abrego, Eero J. Vesterinen, Torsti Schulz, Tomas Roslin, Tommi Nyman
{"title":"Imprints of latitude, host taxon, and decay stage on fungus-associated arthropod communities","authors":"Janne S. Koskinen, Nerea Abrego, Eero J. Vesterinen, Torsti Schulz, Tomas Roslin, Tommi Nyman","doi":"10.1002/ecm.1516","DOIUrl":"10.1002/ecm.1516","url":null,"abstract":"<p>Interactions among fungi and insects involve hundreds of thousands of species. While insect communities on plants have formed some of the classic model systems in ecology, fungus-based communities and the forces structuring them remain poorly studied by comparison. We characterize the arthropod communities associated with fruiting bodies of eight mycorrhizal basidiomycete fungus species from three different orders along a 1200-km latitudinal gradient in northern Europe. We hypothesized that, matching the pattern seen for most insect taxa on plants, we would observe a general decrease in fungal-associated species with latitude. Against this backdrop, we expected local communities to be structured by host identity and phylogeny, with more closely related fungal species sharing more similar communities of associated organisms. As a more unique dimension added by the ephemeral nature of fungal fruiting bodies, we expected further imprints generated by successional change, with younger fruiting bodies harboring communities different from older ones. Using DNA metabarcoding to identify arthropod communities from fungal fruiting bodies, we found that latitude left a clear imprint on fungus-associated arthropod community composition, with host phylogeny and decay stage of fruiting bodies leaving lesser but still-detectable effects. The main latitudinal imprint was on a high arthropod species turnover, with no detectable pattern in overall species richness. Overall, these findings paint a new picture of the drivers of fungus-associated arthropod communities, suggesting that latitude will not affect how many arthropod species inhabit a fruiting body but, rather, what species will occur in it and at what relative abundances (as measured by sequence read counts). These patterns upset simplistic predictions regarding latitudinal gradients in species richness and in the strength of biotic interactions.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecm.1516","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41556100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jelena H. Pantel, Thomas Lamy, Maxime Dubart, Jean-Pierre Pointier, Philippe Jarne, Patrice David
{"title":"Metapopulation dynamics of multiple species in a heterogeneous landscape","authors":"Jelena H. Pantel, Thomas Lamy, Maxime Dubart, Jean-Pierre Pointier, Philippe Jarne, Patrice David","doi":"10.1002/ecm.1515","DOIUrl":"10.1002/ecm.1515","url":null,"abstract":"<p>Characterizing the diversity of demographic strategies among species can inform research in topics such as trait syndromes, community stability, coexistence, and ecological succession. However, this diversity can depend on the spatial scale considered: at the landscape scale, species often form metapopulations, that is sets of local, sometimes short-lived, populations, inhabiting discrete habitat patches. Metapopulation dynamics are most frequently analyzed in individual species or pairs of interacting species because of the large amount of data required for multiple species, and because species vary in their perceptions of what constitutes a favorable or unfavorable habitat. Here we evaluate, using a case study, whether a metapopulation model can be used to generate accurate estimates of demographic parameters and to describe the diversity of dynamics, responses to environment, and prospects of long-term persistence in a guild of species inhabiting a common fragmented landscape. We applied this approach to a guild of 22 mollusk species that inhabit freshwater habitats on two islands of Guadeloupe, to compare metapopulation dynamics among species. We analyzed a 15-year time series of occupancy records for 278 sites using a multistate occupancy model that estimated colonization and extinction rates as a function of site-specific and year-specific environmental covariates, then used model results to simulate future island metapopulation dynamics. Despite the diverse array of metapopulation trajectories—a mix of species with either stable, increasing, declining, or fluctuating metapopulations—and the inherent challenges associated with such data (e.g., imperfect detection, spatial and temporal heterogeneity), our model accurately captured among-patch variation in suitability for many mollusk taxa. The dynamics of rare species or species with habitat preferences not fully captured by the retained set of covariates were less well described. For several species, we detected a negative correlation between extinction and colonization. This variation in habitat suitability created species-specific extinction-resistant pockets in the landscape. Our comparative analysis also revealed that species had distinct strategies for metapopulation dynamics, such as “fast-turnover” species with both a high proportion of occupied sites and a high rate of site extinction in the landscape.</p>","PeriodicalId":11505,"journal":{"name":"Ecological Monographs","volume":"92 3","pages":""},"PeriodicalIF":6.1,"publicationDate":"2022-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41398030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}