Effects of abiotic factors and species interactions on estimates of male plant function: a meta-analysis

Red alga species belonging to the Porphyra and Pyropia genera (commonly known as Nori), which are widely consumed and commercialized due to their high nutritional value. These species have a carotenoid profile dominated by xanthophylls, mostly lutein and zeaxanthin, which have relevant benefits for human health. The effects of different abiotic factors on xanthophyll synthesis in these species have been scarcely studied, despite their health benefits. The objectives of this study were (i) to identify the abiotic factors that enhance the synthesis of xanthophylls in Porphyra/Pyropia species by conducting a systematic review and meta-analysis of the xanthophyll content found in the literature, and (ii) to recommend a culture method that would allow a significant accumulation of these compounds in the biomass of these species. The results show that salinity significantly affected the content of total carotenoids and led to higher values under hypersaline conditions (70,247.91 µg/g dm at 55 psu). For lutein and zeaxanthin, the wavelength treatment caused significant differences between the basal and maximum content (4.16–23.47 µg/g dm). Additionally, in Pyropia spp., the total carotenoids were considerably higher than in Porphyra spp.; however, the lutein and zeaxanthin contents were lower. We discuss the specific conditions for each treatment and the relation to the ecological distribution of these species.

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Temperature as a modulator of sexual selection

10.32942/osf.io/hqvmd ◽

2018 ◽

Author(s):

Roberto García-Roa ◽

Francisco Garcia-Gonzalez ◽

Daniel W.A. Noble ◽

Pau Carazo

Keyword(s):

Global Warming ◽

Sexual Selection ◽

Thermal Environment ◽

Abiotic Factors ◽

Meta Analysis ◽

Population Viability ◽

Order Effects ◽

Secondary Sexual Traits ◽

Trade Offs ◽

Wide Range

A central question in ecology and evolution is to understand why sexual selection varies so much in strength across taxa, and it has long been known that ecological factors are crucial to this respect. Temperature is a particularly critical abiotic ecological factor that can drastically modulate a wide range of physiological, morphological and behavioural traits, impacting individuals and populations at a global taxonomic scale. Furthermore, temperature exhibits substantial temporal variation (e.g. daily, seasonally and inter-seasonally), and hence for most species in the wild sexual selection will regularly unfold in a dynamic thermal environment. Unfortunately, studies have so far almost completely neglected the role of temperature as a modulator of sexual selection. Here, we outline the main pathways via which temperature can affect the intensity and form (i.e. mechanisms) of sexual selection, via: a) direct effects on secondary sexual traits and preferences (i.e. trait variance, opportunity for selection and trait-fitness covariance), and b) indirect effects on key mating parameters, sex-specific reproductive costs/benefits, trade-offs, demography and correlated abiotic factors. Building upon this framework, we show that, by focusing exclusively on the first order effects that environmental temperature has on traits linked with individual fitness and population viability, current global warming studies may be ignoring important eco-evolutionary feedbacks mediated by sexual selection. Finally, we tested the general prediction that temperature modulates sexual selection by conducting a meta-analysis of available studies experimentally manipulating temperature and reporting effects on the variance of male/female reproductive success and/or traits under sexual selection. Our results show a clear association between temperature and sexual selection measures in both sexes. In short, we suggest that studying the feedback between temperature and sexual selection processes can be vital to better understand variation in the strength of sexual selection in nature, and its consequences for population viability in response to environmental change (e.g. global warming).

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Answers.

Key questions in ecology: a study and revision guide ◽

10.1079/9781789247572.0179 ◽

2020 ◽

pp. 179-214

Author(s):

Paul A. Rees

Keyword(s):

Community Ecology ◽

Population Ecology ◽

Species Interactions ◽

Abiotic Factors ◽

Multiple Choice ◽

Ecological Genetics ◽

Major Topic ◽

Production Ecology ◽

Material Cycles ◽

Ecological Methods

Abstract A multiple choice question has a stem (the 'question'), a key (the 'answer') and a number of distracters (wrong answers intended to distract the student from the key). This part of the book contains the key to each question along with a brief explanation of why this is correct and, in some cases, what the distracters mean. The questions are grouped into 10 major topic areas: (1) The history and foundations of ecology, (2) Abiotic factors and environmental monitoring, (3) Taxonomy and biodiversity, (4) Energy flow and production ecology, (5) Nutrient and material cycles, (6) Ecophysiology, (7) Population ecology, (8) Community ecology and species interactions, (9) Ecological genetics and evolution, (10) Ecological methods and statistics.

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Aridity weakens population-level effects of multiple species interactions on Hibiscus meyeri

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1708436115 ◽

2017 ◽

Vol 115 (3) ◽

pp. 543-548 ◽

Cited By ~ 13

Author(s):

Allison M. Louthan ◽

Robert M. Pringle ◽

Jacob R. Goheen ◽

Todd M. Palmer ◽

William F. Morris ◽

...

Keyword(s):

Population Growth ◽

Species Interactions ◽

Abiotic Factors ◽

Population Level ◽

Distinct Species ◽

High Elevation ◽

Relative Strength ◽

Herbaceous Plant ◽

Species Abundances ◽

Multiple Species

Predicting how species’ abundances and ranges will shift in response to climate change requires a mechanistic understanding of how multiple factors interact to limit population growth. Both abiotic stress and species interactions can limit populations and potentially set range boundaries, but we have a poor understanding of when and where each is most critical. A commonly cited hypothesis, first proposed by Darwin, posits that abiotic factors (e.g., temperature, precipitation) are stronger determinants of range boundaries in apparently abiotically stressful areas (“stress” indicates abiotic factors that reduce population growth), including desert, polar, or high-elevation environments, whereas species interactions (e.g., herbivory, competition) play a stronger role in apparently less stressful environments. We tested a core tenet of this hypothesis—that population growth rate is more strongly affected by species interactions in less stressful areas—using experimental manipulations of species interactions affecting a common herbaceous plant, Hibiscus meyeri (Malvaceae), across an aridity gradient in a semiarid African savanna. Population growth was more strongly affected by four distinct species interactions (competition with herbaceous and shrubby neighbors, herbivory, and pollination) in less stressful mesic areas than in more stressful arid sites. However, contrary to common assumptions, this effect did not arise because of greater density or diversity of interacting species in less stressful areas, but rather because aridity reduced sensitivity of population growth to these interactions. Our work supports classic predictions about the relative strength of factors regulating population growth across stress gradients, but suggests that this pattern results from a previously unappreciated mechanism that may apply to many species worldwide.

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Long-term empirical evidence of ocean warming leading to tropicalization of fish communities, increased herbivory, and loss of kelp

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1610725113 ◽

2016 ◽

Vol 113 (48) ◽

pp. 13791-13796 ◽

Cited By ~ 151

Author(s):

Adriana Vergés ◽

Christopher Doropoulos ◽

Hamish A. Malcolm ◽

Mathew Skye ◽

Marina Garcia-Pizá ◽

...

Keyword(s):

Empirical Evidence ◽

Species Interactions ◽

Abiotic Factors ◽

Fish Communities ◽

Kelp Forests ◽

Ecological Communities ◽

Epilithic Algae ◽

Fish Herbivory ◽

Eastern Australia

Some of the most profound effects of climate change on ecological communities are due to alterations in species interactions rather than direct physiological effects of changing environmental conditions. Empirical evidence of historical changes in species interactions within climate-impacted communities is, however, rare and difficult to obtain. Here, we demonstrate the recent disappearance of key habitat-forming kelp forests from a warming tropical–temperate transition zone in eastern Australia. Using a 10-y video dataset encompassing a 0.6 °C warming period, we show how herbivory increased as kelp gradually declined and then disappeared. Concurrently, fish communities from sites where kelp was originally abundant but subsequently disappeared became increasingly dominated by tropical herbivores. Feeding assays identified two key tropical/subtropical herbivores that consumed transplanted kelp within hours at these sites. There was also a distinct increase in the abundance of fishes that consume epilithic algae, and much higher bite rates by this group at sites without kelp, suggesting a key role for these fishes in maintaining reefs in kelp-free states by removing kelp recruits. Changes in kelp abundance showed no direct relationship to seawater temperatures over the decade and were also unrelated to other measured abiotic factors (nutrients and storms). Our results show that warming-mediated increases in fish herbivory pose a significant threat to kelp-dominated ecosystems in Australia and, potentially, globally.

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Coexistence patterns of soil methanogens are closely tied to methane generation and community assembly in rice paddies

Microbiome ◽

10.1186/s40168-020-00978-8 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Dong Li ◽

Haowei Ni ◽

Shuo Jiao ◽

Yahai Lu ◽

Jizhong Zhou ◽

...

Keyword(s):

Species Interactions ◽

Functional Significance ◽

Abiotic Factors ◽

Mean Annual Temperature ◽

Rice Paddies ◽

Asian Continent ◽

Local Networks ◽

Methane Generation ◽

Complex Interactions ◽

Archaeal Communities

Abstract Background Soil methanogens participate in complex interactions, which determine the community structures and functions. Studies continue to seek the coexistence patterns of soil methanogens, influencing factors and the contribution to methane (CH4) production, which are regulated primarily by species interactions, and the functional significance of these interactions. Here, methane emissions were measured in rice paddies across the Asian continent, and the complex interactions involved in coexistence patterns of methanogenic archaeal communities were represented as pairwise links in co-occurrence networks. Results The network topological properties, which were positively correlated with mean annual temperature, were the most important predictor of CH4 emissions among all the biotic and abiotic factors. The methanogenic groups involved in commonly co-occurring links among the 39 local networks contributed most to CH4 emission (53.3%), much higher than the contribution of methanogenic groups with endemic links (36.8%). The potential keystone taxa, belonging to Methanobacterium, Methanocella, Methanothrix, and Methanosarcina, possessed high linkages with the methane generation functional genes mcrA, fwdB, mtbA, and mtbC. Moreover, the commonly coexisting taxa showed a very different assembly pattern, with ~ 30% determinism and ~ 70% stochasticity. In contrast, a higher proportion of stochasticity (93~99%) characterized the assembly of endemically coexisting taxa. Conclusions These results suggest that the coexistence patterns of microbes are closely tied to their functional significance, and the potential importance of common coexistence further imply that complex networks of interactions may contribute more than species diversity to soil functions.

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Is Phylogeographic Congruence Predicted by Historical Habitat Stability, or Ecological Co-associations?

Insect Systematics and Diversity ◽

10.1093/isd/ixab018 ◽

2021 ◽

Vol 5 (5) ◽

Author(s):

Ryan C Garrick ◽

Chaz Hyseni ◽

Ísis C Arantes ◽

Louis G Zachos ◽

Peter C Zee ◽

...

Keyword(s):

Dna Sequences ◽

Species Interactions ◽

Ecological Niche Modeling ◽

Nuclear Dna ◽

Abiotic Factors ◽

Genetic Data ◽

Phylogeographic Structure ◽

Biotic Factors ◽

Effective Population ◽

Species Responses

Abstract Comparative phylogeographic studies can distinguish between idiosyncratic and community-wide responses to past environmental change. However, to date, the impacts of species interactions have been largely overlooked. Here we used non-genetic data to characterize two competing scenarios about expected levels of congruence among five deadwood-associated (saproxylic) invertebrate species (i.e., a wood-feeding cockroach, termite, and beetle; a predatory centipede, and a detritivorous millipede) from the southern Appalachian Mountains—a globally recognized center of endemism. Under one scenario, abiotic factors primarily drove species’ responses, with predicted congruence based on the spatial overlap of climatically stable habitat areas estimated for each species via ecological niche modeling. The second scenario considered biotic factors to be most influential, with proxies for species interactions used to predict congruence. Analyses of mitochondrial and nuclear DNA sequences focused on four axes of comparison: the number and geographic distribution of distinct spatial-genetic clusters, phylogeographic structure, changes in effective population size, and historical gene flow dynamics. Overall, we found stronger support for the ecological co-associations scenario, suggesting an important influence of biotic factors in constraining or facilitating species’ responses to Pleistocene climatic cycles. However, there was an imperfect fit between predictions and outcomes of genetic data analyses. Thus, while thought-provoking, conclusions remain tentative until additional data on species interactions becomes available. Ultimately, the approaches presented here advance comparative phylogeography by expanding the scope of inferences beyond solely considering abiotic drivers, which we believe is too simplistic. This work also provides conservation-relevant insights into the evolutionary history of a functionally important ecological community.

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A quantitative synthesis of soil microbial effects on plant species coexistence

10.1101/2021.11.12.467958 ◽

2021 ◽

Author(s):

Xinyi Yan ◽

Jonathan M. Levine ◽

Gaurav S. Kandlikar

Keyword(s):

Species Interactions ◽

Soil Microbes ◽

Species Coexistence ◽

Meta Analysis ◽

Priority Effects ◽

Soil Microbial ◽

Plant Soil ◽

Niche Differences ◽

Plant Coexistence ◽

Microbial Effects

Soil microorganisms play a major role in shaping plant diversity, not only through their direct effects as pathogens, mutualists, and decomposers, but also by altering interactions between plants. In particular, previous research has shown that the soil community often generates frequency-dependent feedback loops among plants that can either destabilize species interactions, or generate stabilizing niche differences that promote species coexistence. However, recent insights from modern coexistence theory have shown that microbial effects on plant coexistence depend not only on these stabilizing or destabilizing effects, but also on the degree to which they generate competitive fitness differences. While many previous experiments have generated the data necessary for evaluating microbially mediated fitness differences, these effects have rarely been quantified in the literature. Here we present a meta-analysis of data from 50 studies, which we used to quantify the microbially mediated (de)stabilization and fitness differences derived from a classic plant-soil feedback model. Across 518 pairwise comparisons, we found that soil microbes generated both stabilization (or destabilization) and fitness differences, but also that the microbially mediated fitness differences dominated. As a consequence, if plants are otherwise equivalent competitors, the balance of soil microbe-generated (de)stabilization and fitness differences drives species exclusion much more frequently than coexistence or priority effects. Our work shows that microbially mediated fitness differences are an important but overlooked effect of soil microbes on plant coexistence. This finding paves the way for a more complete understanding of the processes that maintain plant biodiversity.

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Parasitism to mutualism continuum for Joshua trees inoculated with different communities of arbuscular mycorrhizal fungi from a desert elevation gradient

PLoS ONE ◽

10.1371/journal.pone.0256068 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256068

Author(s):

Jennifer T. Harrower ◽

Gregory S. Gilbert

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Species Interactions ◽

High Throughput Sequencing ◽

Abiotic Factors ◽

Elevation Gradient ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Climate Gradient ◽

Joshua Trees

Most desert plants form symbiotic relationships with arbuscular mycorrhizal fungi (AMF), yet fungal identity and impacts on host plants remain largely unknown. Despite widespread recognition of the importance of AMF relationships for plant functioning, we do not know how fungal community structure changes across a desert climate gradient, nor the impacts of different fungal communities on host plant species. Because climate change can shape the distribution of species through effects on species interactions, knowing how the ranges of symbiotic partners are geographically structured and the outcomes of those species interactions informs theory and improves management recommendations. Here we used high throughput sequencing to examine the AMF community of Joshua trees along a climate gradient in Joshua Tree National Park. We then used a range of performance measures and abiotic factors to evaluate how different AMF communities may affect Joshua tree fitness. We found that fungal communities change with elevation resulting in a spectrum of interaction outcomes from mutualism to parasitism that changed with the developmental stage of the plant. Nutrient accumulation and the mycorrhizal growth response of Joshua tree seedlings inoculated with fungi from the lowest (warmest) elevations was first negative, but after 9 months had surpassed that of plants with other fungal treatments. This indicates that low elevation fungi are costly for the plant to initiate symbiosis, yet confer benefits over time. The strong relationship between AMF community and plant growth suggests that variation in AMF community may have long term consequences for plant populations along an elevation gradient.

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Unified Framework I: Interspecific Interactions and Species Diversity in Drylands

Biodiversity in Drylands ◽

10.1093/oso/9780195139853.003.0013 ◽

2005 ◽

Author(s):

Gary A. Polis ◽

Robert D. Holt

Keyword(s):

Species Diversity ◽

Species Interactions ◽

Abiotic Factors ◽

Biotic Interactions ◽

Annual Plants ◽

Ecological Processes ◽

Systematic Analysis ◽

Local Diversity ◽

High Diversity ◽

Regional Processes

The goal of this chapter is to delineate how abiotic conditions, regional processes, and species interactions influence species diversity at local scales in drylands. There is a very rich literature that bears on this topic, but here we focus on mechanisms that promote or constrain local diversity and ask how these factors apply to deserts. We ask, “What is different about deserts, relative to other habitats, in their patterns of diversity, temporal variability in productivity, and spatial heterogeneity?” We assess how such differences might modify extant theory, and sketch relevant examples. Compared with other biomes, productivity, population densities, and community biomass are much lower in deserts, and temporal heterogeneity is typically higher. Do these differences imply distinct ecological processes and patterns in deserts? Or, do processes operate in deserts in similar ways as in tropical forests or grasslands? For example, it is often assumed that abiotic factors are more important in deserts. If so, how do abiotic factors modify biotic interactions? How do we integrate physical and biotic interactions? More generally, we ask what should be the main goals and approaches of a research program to understand the role of species interactions in determining community structure in drylands, as modified by abiotic factors and regional processes. . . . What Is Different About Drylands? . . . Deserts are traditionally perceived as relatively simple ecosystems harboring low species diversity. Yet increasing evidence suggests that desert communities can be highly diverse and complex. To our knowledge the only systematic analysis of the relative diversity in desert versus nondesert communities was compiled by Polis (1991a). These data suggest that patterns differ widely among taxonomic groups. In some cases, deserts support high diversity, comparable to or even higher than nonarid areas (see Polis 1991b). For example, while avian (Wiens 1991) and anuran (Woodward and Mitchell 1991) diversities are low compared with other biomes, desert annual plants show extremely high species diversity (Inouye 1991). Ants, succulent plants, lizards, scorpions, and tenebrionid beetles also have relatively high diversity in deserts (Polis 1991a–c, Wiens 1991). But, while very high diversity may occur, local diversity varies greatly in space and time (e.g., ants and annual plants: Danin 1977, Inouye 1991, MacKay 1991).

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