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Zhang H, Ni T, Liu X, Ma B, Huang T, Zhao D, Li H, Chen K, Liu T. Ignored microbial-induced taste and odor in drinking water reservoirs: Novel insight into actinobacterial community structure, assembly, and odor-producing potential. WATER RESEARCH 2024; 264:122219. [PMID: 39121820 DOI: 10.1016/j.watres.2024.122219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 06/13/2024] [Accepted: 08/03/2024] [Indexed: 08/12/2024]
Abstract
The presence of actinobacteria in reservoirs can lead to taste and odor issues, posing potential risks to the safety of drinking water supply. However, the response of actinobacterial communities to environmental factors in drinking water reservoirs remains largely unexplored. To address this gap, this study investigated the community structure and metabolic characteristics of odor-producing actinobacteria in water reservoirs across northern and southern China. The findings revealed differences in the actinobacterial composition across the reservoirs, with Mycobacterium sp. and Candidatus Nanopelagicus being the most prevalent genera. Notably, water temperature, nutrient levels, and metal concentrations were associated with differences in actinobacterial communities, with stochastic processes playing a major role in shaping the community assembly. In addition, three strains of odor-producing actinobacteria were cultured in raw reservoir water, namely Streptomyces antibioticus LJH21, Streptomyces sp. ZEU13, and Streptomyces sp. PQK19, with peak ATP concentrations of 51 nmol/L, 66 nmol/L, and 70 nmol/L, respectively, indicating that odor-producing actinobacteria could remain metabolically active under poor nutrient pressure. Additionally, Streptomyces antibioticus LJH21 produced the highest concentration of geosmin at 24.4 ng/L. These findings enhance our understanding of regional variances and reproductive metabolic mechanisms of actinobacteria in drinking water reservoirs, providing a solid foundation for improving drinking water quality control, especially for taste and odor.
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Affiliation(s)
- Haihan Zhang
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Tongchao Ni
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiang Liu
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Ben Ma
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Daijuan Zhao
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Haiyun Li
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Kaige Chen
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tao Liu
- Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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2
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Fung T, Pande J, Shnerb NM, O'Dwyer JP, Chisholm RA. Processes governing species richness in communities exposed to temporal environmental stochasticity: A review and synthesis of modelling approaches. Math Biosci 2024; 369:109131. [PMID: 38113973 DOI: 10.1016/j.mbs.2023.109131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 11/10/2023] [Accepted: 12/15/2023] [Indexed: 12/21/2023]
Abstract
Research into the processes governing species richness has often assumed that the environment is fixed, whereas realistic environments are often characterised by random fluctuations over time. This temporal environmental stochasticity (TES) changes the demographic rates of species populations, with cascading effects on community dynamics and species richness. Theoretical and applied studies have used process-based mathematical models to determine how TES affects species richness, but under a variety of frameworks. Here, we critically review such studies to synthesise their findings and draw general conclusions. We first provide a broad mathematical framework encompassing the different ways in which TES has been modelled. We then review studies that have analysed models with TES under the assumption of negligible interspecific interactions, such that a community is conceptualised as the sum of independent species populations. These analyses have highlighted how TES can reduce species richness by increasing the frequency at which a species becomes rare and therefore prone to extinction. Next, we review studies that have relaxed the assumption of negligible interspecific interactions. To simplify the corresponding models and make them analytically tractable, such studies have used mean-field theory to derive fixed parameters representing the typical strength of interspecific interactions under TES. The resulting analyses have highlighted community-level effects that determine how TES affects species richness, for species that compete for a common limiting resource. With short temporal correlations of environmental conditions, a non-linear averaging effect of interspecific competition strength over time gives an increase in species richness. In contrast, with long temporal correlations of environmental conditions, strong selection favouring the fittest species between changes in environmental conditions results in a decrease in species richness. We compare such results with those from invasion analysis, which examines invasion growth rates (IGRs) instead of species richness directly. Qualitative differences sometimes arise because the IGR is the expected growth rate of a species when it is rare, which does not capture the variation around this mean or the probability of the species becoming rare. Our review elucidates key processes that have been found to mediate the negative and positive effects of TES on species richness, and by doing so highlights key areas for future research.
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Affiliation(s)
- Tak Fung
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore 117558, Singapore.
| | - Jayant Pande
- Department of Physical and Natural Sciences, FLAME University, Pune, Maharashtra 412115, India
| | - Nadav M Shnerb
- Department of Physics, Bar-Ilan University, Ramat Gan 52900, Israel
| | - James P O'Dwyer
- Department of Plant Biology, School of Integrative Biology, University of Illinois, 505, South Goodwin Avenue, Urbana, IL 61801, United States
| | - Ryan A Chisholm
- Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore 117558, Singapore
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3
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Li D, Wu J. Canopy nitrogen addition and understory removal destabilize the microbial community in a subtropical Chinese fir plantation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 354:120407. [PMID: 38368803 DOI: 10.1016/j.jenvman.2024.120407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/04/2024] [Accepted: 02/15/2024] [Indexed: 02/20/2024]
Abstract
Subtropical Chinese fir plantations have been experiencing increased nitrogen deposition and understory management because of human activities. Nevertheless, effect of increased nitrogen deposition and understory removal in the plantations on microbial community stability and the resulting consequences for ecosystem functioning is still unclear. We carried out a 5-year experiment of canopy nitrogen addition (2.5 g N m-2 year-1), understory removal, and their combination to assess their influences on microbial community stability and functional potentials in a subtropical Chinese fir plantation. Nitrogen addition, understory removal, and their combination reduced soil bacterial diversity (OUT richness, Inverse Simpson index, Shannon index, and phylogenetic diversity) by 11-18%, 15-24%, and 19-31%; reduced fungal diversity indexes by 3-5%, 5-6%, and 5-7%, respectively. We found that environmental filtering and interspecific interactions together determined changes in bacterial community stability, while changes in fungal community stability were mainly caused by environmental filtering. Fungi were more stable than bacteria under disturbances, possibly from having a more stable network structure. Furthermore, we found that microbial community stability was linked to changes in microbial community functional potentials. Importantly, we observed synergistic interactions between understory removal and nitrogen addition on bacterial diversity, network structure, and community stability. These findings suggest that understory plants play a significant role in promoting soil microbial community stability in subtropical Chinese fir plantations and help to mitigate the negative impacts of nitrogen addition. Hence, it is crucial to retain understory vegetation as important components of subtropical plantations.
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Affiliation(s)
- Debao Li
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming, 650 500, China; Laboratory of Soil Ecology and Health in Universities of Yunnan Province, Yunnan University, Kunming, 650500, China
| | - Jianping Wu
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming, 650 500, China; Laboratory of Soil Ecology and Health in Universities of Yunnan Province, Yunnan University, Kunming, 650500, China.
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4
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Eichenwald AJ, Fefferman NH, Reed JM. Potential extinction cascades in a desert ecosystem: Linking food web interactions to community viability. Ecol Evol 2024; 14:e10930. [PMID: 38362165 PMCID: PMC10867880 DOI: 10.1002/ece3.10930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 11/27/2023] [Accepted: 12/05/2023] [Indexed: 02/17/2024] Open
Abstract
Desert communities are threatened with species loss due to climate change, and their resistance to such losses is unknown. We constructed a food web of the Mojave Desert terrestrial community (300 nodes, 4080 edges) to empirically examine the potential cascading effects of bird extinctions on this desert network, compared to losses of mammals and lizards. We focused on birds because they are already disappearing from the Mojave, and their relative thermal vulnerabilities are known. We quantified bottom-up secondary extinctions and evaluated the relative resistance of the community to losses of each vertebrate group. The impact of random bird species loss was relatively low compared to the consequences of mammal (causing the greatest number of cascading losses) or reptile loss, and birds were relatively less likely to be in trophic positions that could drive top-down effects in apparent competition and tri-tropic cascade motifs. An avian extinction cascade with year-long resident birds caused more secondary extinctions than the cascade involving all bird species for randomized ordered extinctions. Notably, we also found that relatively high interconnectivity among avian species has formed a subweb, enhancing network resistance to bird losses.
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Affiliation(s)
| | - Nina H. Fefferman
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTennesseeUSA
| | - J. Michael Reed
- Department of BiologyTufts UniversityMedfordMassachusettsUSA
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5
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Steidinger BS, Büntgen U, Stobbe U, Tegel W, Sproll L, Haeni M, Moser B, Bagi I, Bonet J, Buée M, Dauphin B, Martínez‐Peña F, Molinier V, Zweifel R, Egli S, Peter M. The fall of the summer truffle: Recurring hot, dry summers result in declining fruitbody production of Tuber aestivum in Central Europe. GLOBAL CHANGE BIOLOGY 2022; 28:7376-7390. [PMID: 36200354 PMCID: PMC9828532 DOI: 10.1111/gcb.16424] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 08/14/2022] [Indexed: 06/16/2023]
Abstract
Global warming is pushing populations outside their range of physiological tolerance. According to the environmental envelope framework, the most vulnerable populations occur near the climatic edge of their species' distributions. In contrast, populations from the climatic center of the species range should be relatively buffered against climate warming. We tested this latter prediction using a combination of linear mixed effects and machine learning algorithms on an extensive, citizen-scientist generated dataset on the fruitbody productivity of the Burgundy (aka summer) truffle (Tuber aestivum Vittad.), a keystone, ectomycorrhizal tree-symbiont occurring on a wide range of temperate climates. T. aestivum's fruitbody productivity was monitored at 3-week resolution over up to 8 continuous years at 20 sites distributed in the climatic center of its European distribution in southwest Germany and Switzerland. We found that T. aestivum fruitbody production is more sensitive to summer drought than would be expected from the breadth of its species' climatic niche. The monitored populations occurring nearly 5°C colder than the edge of their species' climatic distribution. However, interannual fruitbody productivity (truffle mass year-1 ) fell by a median loss of 22% for every 1°C increase in summer temperature over a site's 30-year mean. Among the most productive monitored populations, the temperature sensitivity was even higher, with single summer temperature anomalies of 3°C sufficient to stop fruitbody production altogether. Interannual truffle productivity was also related to the phenology of host trees, with ~22 g less truffle mass for each 1-day reduction in the length of the tree growing season. Increasing summer drought extremes are therefore likely to reduce fruiting among summer truffle populations throughout Central Europe. Our results suggest that European T. aestivum may be a mosaic of vulnerable populations, sensitive to climate-driven declines at lower thresholds than implied by its species distribution model.
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Affiliation(s)
- Brian S. Steidinger
- Department of EcologyUniversity of KonstanzKonstanzGermany
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Ulf Büntgen
- Global Change Research Centre (Czech Globe)BrnoCzech Republic
- Department of GeographyUniversity of CambridgeCambridgeUK
- Department of Geography, Faculty of ScienceMasaryk UniversityBrnoCzech Republic
| | | | - Willy Tegel
- Forest GrowthAlbert‐Ludwigs UniversityFreiburgGermany
| | | | - Matthias Haeni
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Barbara Moser
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | | | | | - Marc Buée
- Laboratory of Excellence ARBRE, INRAE‐Grand Est, Interactions Arbres/MicroorganismesINRAE, UMR 1136 INRAE‐University of LorraineChampenouxFrance
| | - Benjamin Dauphin
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Fernando Martínez‐Peña
- Agrifood Research and Technology Centre of Aragon CITAZaragozaSpain
- European Mycological Institute EGTC‐EMISoriaSpain
| | - Virginie Molinier
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Simon Egli
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - Martina Peter
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
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6
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Peel K, Evans D, Emary C. Ternary network models for disturbed ecosystems. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220619. [PMID: 36303942 PMCID: PMC9597174 DOI: 10.1098/rsos.220619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
The complex network of interactions between species makes understanding the response of ecosystems to disturbances an enduring challenge. One commonplace way to deal with this complexity is to reduce the description of a species to a binary presence-absence variable. Though convenient, this limits the patterns of behaviours representable within such models. We address these shortcomings by considering discrete population models that expand species descriptions beyond the binary setting. Specifically, we focus on ternary (three-state) models which, alongside presence and absence, additionally permit species to become overabundant. We apply this ternary framework to the robustness analysis of model ecosystems and show that this expanded description permits the modelling of top-down extinction cascades emerging from consumer pressure or mesopredator release. Results therefore differ significantly from those seen in binary models, where such effects are absent. We also illustrate how this method opens up the modelling of ecosystem disturbances outside the scope of binary models, namely those in which species are externally raised to overabundance. Our method therefore has the potential to provide a richer description of ecosystem dynamics and their disturbances, while at the same time preserving the conceptual simplicity of familiar binary approaches.
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Affiliation(s)
- Kieran Peel
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK
| | - Darren Evans
- Natural and Environmental Sciences, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK
| | - Clive Emary
- School of Mathematics, Statistics and Physics, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK
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7
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Merging theory and experiments to predict and understand coextinctions. Trends Ecol Evol 2022; 37:886-898. [DOI: 10.1016/j.tree.2022.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 11/20/2022]
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8
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Aung KMM, Chen HH, Segar ST, Miao BG, Peng YQ, Liu C. Changes in temperature alter competitive interactions and overall structure of fig wasp communities. J Anim Ecol 2022; 91:1303-1315. [PMID: 35420162 DOI: 10.1111/1365-2656.13701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 03/17/2022] [Indexed: 11/30/2022]
Abstract
Organisms exist within ecological networks, connected through interactions such as parasitism, predation and mutualism which can modify their abundance and distribution within habitat patches. Differential species responses make it hard to predict the influence of climate change at the community scale. Understanding the interplay between climate and biotic interactions can improve our predictions of how ecosystems will respond to current global warming. We aim to understand how climate affects the multi-trophic biotic interactions as well as the community structure using the enclosed communities of wasps associated with figs as study system. To examine the presence and strength of multi-trophic species interactions, we first characterized the multi-trophic community of fig wasps associated with Ficus racemosa and then applied hierarchical joint species distribution models, fitted to community monitoring data. We further evaluated the effect of climate on individual species trends as well as inter-specific interactions. We found that the competitive balance shifted to favour non-pollinating galling wasps and disadvantage the dominant pollinator in sub-optimal conditions. Further, sub-optimal conditions for galling wasps facilitated the occurrence of their specialized parasitoid, as changes cascaded across trophic levels and led to alternative community structures. Our results highlight the role of how species interactions can be modified across multiple trophic levels in a fig wasp community according to climate.
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Affiliation(s)
- Khin Me Me Aung
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, China.,Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, China
| | - Huan-Huan Chen
- College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, 655011, China.,Key Laboratory of Yunnan Province Universities of Qujing Natural History and Early Vertebrate Evolution
| | - Simon T Segar
- Agriculture and Environment Department, Harper Adams University, Newport, Shropshire TF10 8NB, UK
| | - Bai-Ge Miao
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, China.,Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, China
| | - Yan-Qiong Peng
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, China.,Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, China
| | - Cong Liu
- Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, United States
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9
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Eisawi KA, Subedi IP, Shaheen T, He H. Impact of land-use changes on ant communities and the retention of ecosystem services in Rashad District, Southern Kordofan, Sudan. S AFR J SCI 2022. [DOI: 10.17159/sajs.2022/11994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The ecological consequences of biodiversity loss are usually the reduction of ecosystem functions. These responses, however, differ depending on the type of land-use change and the ecological setting. We investigated the impact of land-use type and ecosystem functions on the ant assemblage of Rashad District, Sudan. We analysed the effects of three different land uses (soy monoculture, pasture and organic production of vegetables) on the ant community by assessing ant composition in 176 different locations. The collection sites were conventional soy monoculture, pastures, organic agriculture, and native vegetation such as Campo, Kubos, and forests. We recorded 264 ant species on the soil surface of the Rashad District, where 342 to 354 species were thought to exist. Pastures and organic agriculture areas have 61% and 56% of the native myrmecofauna, respectively, while conventional soy monoculture areas are home to only 17% of native ant species. Forest areas present a unique community, and soy monoculture areas have the strongest pattern of biotic homogenisation. We also detected that rare species (of low frequency) were the chief promoters of richness in the Rashad District, and the most threatened with local extinction, due to their low density and low occurrence in agrosystems. Overall, we found that agricultural expansion reduces ant diversity, particularly in soybean crops, and can affect ecosystem functions. To mitigate the reduction in the ant assemblage, we recommend the conservation of multiple natural habitats.
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Affiliation(s)
- Khalid A.E. Eisawi
- College of Forestry, Northwest A&F University, Yangling, China
- College of Forestry and Rangeland, University of East Kordofan, Rashad, Sudan
| | - Indra P. Subedi
- Central Department of Zoology, Tribhuvan University, Kathmandu, Nepal
| | - Tayyab Shaheen
- College of Forestry, Northwest A&F University, Yangling, China
| | - Hong He
- College of Forestry, Northwest A&F University, Yangling, China
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10
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Baumgartner MT, Bianco Faria LD. The sensitivity of complex dynamic food webs to the loss of top omnivores. J Theor Biol 2022; 538:111027. [DOI: 10.1016/j.jtbi.2022.111027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 12/12/2022]
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11
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McLeod AM, Leroux SJ. Incongruent drivers of network, species and interaction persistence in food webs. OIKOS 2021. [DOI: 10.1111/oik.08512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Anne M. McLeod
- Dept of Biology, Memorial Univ. of Newfoundland St John's NL Canada
| | - Shawn J. Leroux
- Dept of Biology, Memorial Univ. of Newfoundland St John's NL Canada
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12
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Eichenwald AJ, Reed JM. An Expanded Framework for Community Viability Analysis. Bioscience 2021. [DOI: 10.1093/biosci/biab034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Community viability analysis (CVA) has been put forth as an analogue for population viability analysis (PVA), an accepted conservation tool for evaluating species-specific threat and management scenarios. The original proposal recommended that CVAs examine resistance-based questions. PVAs, however, are broadly applicable to multiple types of viability questions, suggesting that the original CVA definition may be too narrow. In the present article, we advance an expanded framework in which CVA includes any analysis assessing the status, threats, or management options of an ecological community. We discuss viability questions that can be investigated with CVA. We group those inquiries into categories of resistance, resilience, and persistence, and provide case studies for each. Finally, we broadly present the steps in a CVA.
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Affiliation(s)
- Adam J Eichenwald
- PhD candidate, Tufts University, Medford, Massachusetts, United States
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Microbial Community Resilience across Ecosystems and Multiple Disturbances. Microbiol Mol Biol Rev 2021; 85:85/2/e00026-20. [PMID: 33789927 DOI: 10.1128/mmbr.00026-20] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The ability of ecosystems to withstand disturbances and maintain their functions is being increasingly tested as rates of change intensify due to climate change and other human activities. Microorganisms are crucial players underpinning ecosystem functions, and the recovery of microbial communities from disturbances is therefore a key part of the complex processes determining the fate of ecosystem functioning. However, despite global environmental change consisting of numerous pressures, it is unclear and controversial how multiple disturbances affect microbial community stability and what consequences this has for ecosystem functions. This is particularly the case for those multiple or compounded disturbances that occur more frequently than the normal recovery time. The aim of this review is to provide an overview of the mechanisms that can govern the responses of microbes to multiple disturbances across aquatic and terrestrial ecosystems. We first summarize and discuss properties and mechanisms that influence resilience in aquatic and soil biomes to determine whether there are generally applicable principles. Following, we focus on interactions resulting from inherent characteristics of compounded disturbances, such as the nature of the disturbance, timing, and chronology that can lead to complex and nonadditive effects that are modulating the response of microorganisms.
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14
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Wan JN, Mbari NJ, Wang SW, Liu B, Mwangi BN, Rasoarahona JR, Xin HP, Zhou YD, Wang QF. Modeling impacts of climate change on the potential distribution of six endemic baobab species in Madagascar. PLANT DIVERSITY 2021; 43:117-124. [PMID: 33997544 PMCID: PMC8103343 DOI: 10.1016/j.pld.2020.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 05/12/2023]
Abstract
Madagascar, a globally renowned biodiversity hotspot characterized by high rates of endemism, is one of the few remaining refugia for many plants and animal species. However, global climate change has greatly affected the natural ecosystem and endemic species living in Madagascar, and will likely continue to influence species distribution in the future. Madagascar is home to six endemic baobab (Adansonia spp., Bombacoideae [Malvaceae]) species (Adansonia grandidieri, A. suarezensis, A. madagascariensis, A. perrieri, A. rubrostipa, A. za), which are remarkable and endangered plants. This study aimed to model the current distribution of suitable habitat for each baobab species endemic to Madagascar and determine the effect that climate change will have on suitable baobab habitat by the years 2050 and 2070. The distribution was modeled using MaxEnt based on locality information of 245 occurrence sites of six species from both online database and our own field work. A total of seven climatic variables were used for the modeling process. The present distribution of all six Madagascar's baobabs was largely influenced by temperature-related factors. Although both expansion and contraction of suitable habitat are predicted for all species, loss of original suitable habitat is predicted to be extensive. For the most widespread Madagascar baobab, A. za, more than 40% of its original habitat is predicted to be lost because of climate change. Based on these findings, we recommend that areas predicted to contract in response to climate change should be designated key protection regions for baobab conservation.
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Affiliation(s)
- Jun-Nan Wan
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
| | - Ndungu J. Mbari
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Sheng-Wei Wang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Bing Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
| | - Brian N. Mwangi
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Jean R.E. Rasoarahona
- High School of Agricultural Sciences, University of Antananarivo, P.O. Box 175, Madagascar
| | - Hai-Ping Xin
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
| | - Ya-Dong Zhou
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
| | - Qing-Feng Wang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, Hubei, 430074, PR China
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15
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Häussler J, Barabás G, Eklöf A. A Bayesian network approach to trophic metacommunities shows that habitat loss accelerates top species extinctions. Ecol Lett 2020; 23:1849-1861. [PMID: 32981202 PMCID: PMC7702078 DOI: 10.1111/ele.13607] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/09/2020] [Accepted: 08/14/2020] [Indexed: 11/28/2022]
Abstract
We develop a novel approach to analyse trophic metacommunities, which allows us to explore how progressive habitat loss affects food webs. Our method combines classic metapopulation models on fragmented landscapes with a Bayesian network representation of trophic interactions for calculating local extinction rates. This means that we can repurpose known results from classic metapopulation theory for trophic metacommunities, such as ranking the habitat patches of the landscape with respect to their importance to the persistence of the metacommunity as a whole. We use this to study the effects of habitat loss, both on model communities and the plant‐mammal Serengeti food web dataset as a case study. Combining straightforward parameterisability with computational efficiency, our method permits the analysis of species‐rich food webs over large landscapes, with hundreds or even thousands of species and habitat patches, while still retaining much of the flexibility of explicit dynamical models.
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Affiliation(s)
- Johanna Häussler
- EcoNetLab, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, Leipzig, 04103, Germany.,Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger-Str. 159, Jena, 07743, Germany
| | - György Barabás
- Linköping University, Linköping, SE-58183, Sweden.,MTA-ELTE Theoretical Biology and Evolutionary Ecology Research Group, Pázmány Péter sétány, Budapest, H-1117, Hungary
| | - Anna Eklöf
- Linköping University, Linköping, SE-58183, Sweden
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16
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Tielke A, Karreman J, Vos M. Mild cycles open closed communities to ecological restoration. Restor Ecol 2020. [DOI: 10.1111/rec.13136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ann‐Kathrin Tielke
- Ruhr University Bochum, Faculty of Biology and Biotechnology Theoretical and Applied Biodiversity Research Universitätsstraße 150 44780 Bochum Germany
| | - Japke Karreman
- Institute of Environmental Sciences Leiden University PO Box 9518 2300 RA Leiden The Netherlands
| | - Matthijs Vos
- Ruhr University Bochum, Faculty of Biology and Biotechnology Theoretical and Applied Biodiversity Research Universitätsstraße 150 44780 Bochum Germany
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17
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Habitat Climate Change Vulnerability Index Applied to Major Vegetation Types of the Western Interior United States. LAND 2019. [DOI: 10.3390/land8070108] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We applied a framework to assess climate change vulnerability of 52 major vegetation types in the Western United States to provide a spatially explicit input to adaptive management decisions. The framework addressed climate exposure and ecosystem resilience; the latter derived from analyses of ecosystem sensitivity and adaptive capacity. Measures of climate change exposure used observed climate change (1981–2014) and then climate projections for the mid-21st century (2040–2069 RCP 4.5). Measures of resilience included (under ecosystem sensitivity) landscape intactness, invasive species, fire regime alteration, and forest insect and disease risk, and (under adaptive capacity), measures for topo-climate variability, diversity within functional species groups, and vulnerability of any keystone species. Outputs are generated per 100 km2 hexagonal area for each type. As of 2014, moderate climate change vulnerability was indicated for >50% of the area of 50 of 52 types. By the mid-21st century, all but 19 types face high or very high vulnerability with >50% of the area scoring in these categories. Measures for resilience explain most components of vulnerability as of 2014, with most targeted vegetation scoring low in adaptive capacity measures and variably for specific sensitivity measures. Elevated climate exposure explains increases in vulnerability between the current and mid-century time periods.
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18
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Jeltsch F, Grimm V, Reeg J, Schlägel UE. Give chance a chance: from coexistence to coviability in biodiversity theory. Ecosphere 2019. [DOI: 10.1002/ecs2.2700] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Florian Jeltsch
- Department of Plant Ecology and Nature Conservation University of Potsdam Am Mühlenberg 3 Potsdam‐Golm DE‐14476 Germany
- Berlin‐Brandenburg Institute of Advanced Biodiversity Research (BBIB) Berlin DE‐14195 Germany
| | - Volker Grimm
- Department of Plant Ecology and Nature Conservation University of Potsdam Am Mühlenberg 3 Potsdam‐Golm DE‐14476 Germany
- Department of Ecological Modelling Helmholtz Centre for Environmental Research‐UFZ Permoserstraße 15 Leipzig 04318 Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e Leipzig 04103 Germany
| | - Jette Reeg
- Department of Plant Ecology and Nature Conservation University of Potsdam Am Mühlenberg 3 Potsdam‐Golm DE‐14476 Germany
| | - Ulrike E. Schlägel
- Department of Plant Ecology and Nature Conservation University of Potsdam Am Mühlenberg 3 Potsdam‐Golm DE‐14476 Germany
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Whitebark and Foxtail Pine in Yosemite, Sequoia, and Kings Canyon National Parks: Initial Assessment of Stand Structure and Condition. FORESTS 2019. [DOI: 10.3390/f10010035] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Inventory & Monitoring Division of the U.S. National Park Service conducts long-term monitoring to provide park managers information on the status and trends in biological and environmental attributes including white pines. White pines are foundational species in many subalpine ecosystems and are currently experiencing population declines. Here we present results on the status of whitebark and foxtail pine in the southern Sierra Nevada of California, an area understudied relative to other parts of their ranges. We selected random plot locations in Yosemite, Sequoia, and Kings Canyon national parks using an equal probability spatially-balanced approach. Tree- and plot-level data were collected on forest structure, composition, demography, cone production, crown mortality, and incidence of white pine blister rust and mountain pine beetle. We measured 7899 whitebark pine, 1112 foxtail pine, and 6085 other trees from 2012–2017. All factors for both species were spatially highly variable. Whitebark pine occurred in nearly-pure krummholz stands at or near treeline and as a minor component of mixed species forests. Ovulate cones were observed on 25% of whitebark pine and 69% of foxtail pine. Whitebark pine seedlings were recorded in 58% of plots, and foxtail pine seedlings in only 21% of plots. Crown mortality (8% in whitebark, 6% in foxtail) was low and significantly higher in 2017 compared to previous years. Less than 1% of whitebark and zero foxtail pine were infected with white pine blister rust and <1% of whitebark and foxtail pine displayed symptoms of mountain pine beetle attack. High elevation white pines in the southern Sierra Nevada are healthy compared to other portions of their range where population declines are significant and well documented. However, increasing white pine blister rust and mountain pine beetle occurrence, coupled with climate change projections, portend future declines for these species, underscoring the need for broad-scale collaborative monitoring.
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20
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Clegg T, Ali M, Beckerman AP. The impact of intraspecific variation on food web structure. Ecology 2018; 99:2712-2720. [DOI: 10.1002/ecy.2523] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 07/25/2018] [Accepted: 08/20/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Tom Clegg
- Department of Animal and Plant Sciences University of Sheffield Western Bank Sheffield S10 2TN United Kingdom
| | - Mohammad Ali
- Department of Animal and Plant Sciences University of Sheffield Western Bank Sheffield S10 2TN United Kingdom
| | - Andrew P. Beckerman
- Department of Animal and Plant Sciences University of Sheffield Western Bank Sheffield S10 2TN United Kingdom
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21
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Cordone G, Marina TI, Salinas V, Doyle SR, Saravia LA, Momo FR. Effects of macroalgae loss in an Antarctic marine food web: applying extinction thresholds to food web studies. PeerJ 2018; 6:e5531. [PMID: 30225167 PMCID: PMC6139014 DOI: 10.7717/peerj.5531] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 08/07/2018] [Indexed: 11/20/2022] Open
Abstract
Antarctica is seriously affected by climate change, particularly at the Western Antarctic Peninsula (WAP) where a rapid regional warming is observed. Potter Cove is a WAP fjord at Shetland Islands that constitutes a biodiversity hotspot where over the last years, Potter Cove annual air temperatures averages increased by 0.66 °C, coastal glaciers declined, and suspended particulate matter increased due to ice melting. Macroalgae are the main energy source for all consumers and detritivores of Potter Cove. Some effects of climate change favor pioneer macroalgae species that exploit new ice-free areas and can also decline rates of photosynthesis and intensify competition between species due to the increase of suspended particulate matter. In this study, we evaluated possible consequences of climate change at Potter Cove food web by simulating the extinction of macroalgae and detritus using a topological approach with thresholds of extinction. Thresholds represent the minimum number of incoming links necessary for species' survival. When we simulated the extinctions of macroalgae species at random, a threshold of extinction beyond 50% was necessary to obtain a significant number of secondary extinctions, while with a 75% threshold a real collapse of the food web occurred. Our results indicate that Potter Cove food web is relative robust to macroalgae extinction. This is dramatically different from what has been found in other food webs, where the reduction of 10% in prey intake caused a disproportionate increase of secondary extinctions. Robustness of the Potter Cove food web was mediated by omnivory and redundancy, which had an important relevance in this food web. When we eliminated larger-biomass species more secondary extinctions occurred, a similar response was observed when more connected species were deleted, yet there was no correlation between species of larger-biomass and high-degree. This similarity could be explained because both criteria involved key species that produced an emerging effect on the food web. In this way, large-biomass and high-degree species could be acting as source for species with few trophic interactions or low redundancy. Based on this work, we expect the Potter Cove food web to be robust to changes in macroalgae species caused by climate change until a high threshold of stress is reached, and then negative effects are expected to spread through the entire food web leading to its collapse.
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Affiliation(s)
- Georgina Cordone
- Centro Nacional Patagónico (CCT CONICET-CENPAT), Centro Para el Estudio de Sistemas Marinos (CESIMAR), Puerto Madryn, Chubut, Argentina
| | - Tomás I. Marina
- Universidad Nacional de General Sarmiento, Instituto de Ciencias (ICI), Los Polvorines, Buenos Aires, Argentina
- Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES), Luján, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Centro Austral de Investigaciones Científicas (CADIC), Ushuaia, Tierra del Fuego, Argentina
| | - Vanesa Salinas
- Universidad Nacional de General Sarmiento, Instituto de Ciencias (ICI), Los Polvorines, Buenos Aires, Argentina
| | - Santiago R. Doyle
- Universidad Nacional de General Sarmiento, Instituto de Ciencias (ICI), Los Polvorines, Buenos Aires, Argentina
- Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES), Luján, Buenos Aires, Argentina
| | - Leonardo A. Saravia
- Universidad Nacional de General Sarmiento, Instituto de Ciencias (ICI), Los Polvorines, Buenos Aires, Argentina
- Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES), Luján, Buenos Aires, Argentina
| | - Fernando R. Momo
- Universidad Nacional de General Sarmiento, Instituto de Ciencias (ICI), Los Polvorines, Buenos Aires, Argentina
- Universidad Nacional de Luján, Instituto de Ecología y Desarrollo Sustentable (INEDES), Luján, Buenos Aires, Argentina
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22
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Boehm MM, Scholer MN, Kennedy JJ, Heavyside JM, Daza A, Guevara-Apaza D, Jankowski JE. The Manú Gradient as a study system for bird pollination. Biodivers Data J 2018:e22241. [PMID: 29674936 PMCID: PMC5904515 DOI: 10.3897/bdj.6.e22241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 02/09/2018] [Indexed: 11/19/2022] Open
Abstract
Background This study establishes an altiudinal gradient, spanning from the highland Andes (2400 m) to lowland Amazon, as a productive region for the study of bird pollination in Southeastern Peru. The 'Manú Gradient' has a rich history of ornithological research, the published data and resources from which lay the groundwork for analyses of plant-bird interactions. In this preliminary expedition we documented 44 plants exhibting aspects of the bird pollination syndrome, and made field observations of hummingbird visits at three sites spanning the Manú Gradient: 2800 m (Wayqecha), 1400 m (San Pedro), and 400 m (Pantiacolla). Some of the documented plant taxa are underrepresented in the bird pollination literature and could be promising avenues for future analyses of their pollination biology. The Manú Gradient is currently the focus of a concerted, international effort to describe and study the birds in the region; we propose that this region of Southeastern Peru is a productive and perhaps underestimated system to gain insight into the ecology and evolution of bird pollination. New information Observations were made on 11, 19, and 14 putatively bird pollinated plant species found at the high-, mid- and low-elevation sites along the gradient, respectively. Hummingbirds visited 18 of these plant species, with some plant species being visited by multiple hummingbird species or the same hummingbird species on differing occasions. Morphometric data is presented for putatively bird-pollinated plants, along with bill measurements from hummingbirds captured at each of three sites. Voucher specimens from this study are deposited in the herbaria of the Universidad Nacional de Agraria de La Molina (MOL), Peru and the University of British Columbia (UBC), Canada. The specimens collected represent a ‘snapshot’ of the diversity of bird-pollinated flora as observed over 10 day sampling windows (per site) during the breeding season for hummingbirds of Manú .
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Affiliation(s)
- Mannfred Ma Boehm
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Micah N Scholer
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Jeremiah Jc Kennedy
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Julian M Heavyside
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Aniceto Daza
- Universidad Nacional Agraria La Molina, Lima, Peru
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23
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Individual-Based Modelling of Invasion in Bioaugmented Sand Filter Communities. Processes (Basel) 2018. [DOI: 10.3390/pr6010002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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24
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Transience after disturbance: Obligate species recovery dynamics depend on disturbance duration. Theor Popul Biol 2017; 115:81-88. [PMID: 28479290 DOI: 10.1016/j.tpb.2017.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 02/21/2017] [Accepted: 04/23/2017] [Indexed: 11/20/2022]
Abstract
After a disturbance event, population recovery becomes an important species response that drives ecosystem dynamics. Yet, it is unclear how interspecific interactions impact species recovery from a disturbance and which role the disturbance duration (pulse or press) plays. Here, we analytically derive conditions that govern the transient recovery dynamics from disturbance of a host and its obligately dependent partner in a two-species metapopulation model. We find that, after disturbance, species recovery dynamics depend on the species' role (i.e. host or obligately dependent species) as well as the duration of disturbance. Host recovery starts immediately after the disturbance. In contrast, for obligate species, recovery depends on disturbance duration. After press disturbance, which allows dynamics to equilibrate during disturbance, obligate species immediately start to recover. Yet, after pulse disturbance, obligate species continue declining although their hosts have already begun to increase. Effectively, obligate species recovery is delayed until a necessary host threshold occupancy is reached. Obligates' delayed recovery arises solely from interspecific interactions independent of dispersal limitations, which contests previous explanations. Delayed recovery exerts a two-fold negative effect, because populations continue declining to even smaller population sizes and the phase of increased risk from demographic stochastic extinction in small populations is prolonged. We argue that delayed recovery and its determinants -species interactions and disturbance duration - have to be considered in biodiversity management.
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25
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Kulkarni D, De Laender F. The combined effects of biotic and abiotic stress on species richness and connectance. PLoS One 2017; 12:e0172828. [PMID: 28248985 PMCID: PMC5383007 DOI: 10.1371/journal.pone.0172828] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 02/10/2017] [Indexed: 11/18/2022] Open
Abstract
Food web structure and species richness are both subject to biotic (e.g. predation pressure and resource limitation) and abiotic stress (e.g. environmental change). We investigated the combined effects of both types of stress on richness and connectance, and on their relationship, in a predator-prey system. To this end, we developed a mathematical two trophic level food-web model to investigate the effects of biotic and abiotic stress on food web connectance and species richness. We found negative effects of top-down and bottom-up control on prey and predator richness, respectively. Effects of top-down and bottom-up control were stronger when initial connectance was high and low, respectively. Bottom-up control could either aggravate or buffer negative effects of top-down control. Abiotic stress affecting predator richness had positive indirect effects on prey richness, but only when initial connectance was low. However, no indirect effects on predator richness were observed following direct effects on prey richness. Top-down and bottom-up control selected for weakly connected prey and highly connected predators, thereby decreasing and increasing connectance, respectively. Our simulations suggest a broad range of negative and positive richness-connectance relationships, thereby revisiting the often found negative relationship between richness and connectance in food webs. Our results suggest that (1) initial food-web connectance strongly influences the effects of biotic stress on richness and the occurrence of indirect effects on richness; and (2) the shape of the richness-connectance relationship depends on the type of biotic stress.
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Affiliation(s)
- Devdutt Kulkarni
- Laboratory of Environmental Ecosystem Ecology, Research Unit in Environmental and Evolutionary Biology (URBE), University of Namur, Namur, Belgium
| | - Frederik De Laender
- Laboratory of Environmental Ecosystem Ecology, Research Unit in Environmental and Evolutionary Biology (URBE), University of Namur, Namur, Belgium
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26
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Oysters and the Ecosystem. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/b978-0-12-803472-9.00010-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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27
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Daly AJ, Baetens JM, De Baets B. The impact of resource dependence of the mechanisms of life on the spatial population dynamics of an in silico microbial community. CHAOS (WOODBURY, N.Y.) 2016; 26:123121. [PMID: 28039986 DOI: 10.1063/1.4972788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Biodiversity has a critical impact on ecosystem functionality and stability, and thus the current biodiversity crisis has motivated many studies of the mechanisms that sustain biodiversity, a notable example being non-transitive or cyclic competition. We therefore extend existing microscopic models of communities with cyclic competition by incorporating resource dependence in demographic processes, characteristics of natural systems often oversimplified or overlooked by modellers. The spatially explicit nature of our individual-based model of three interacting species results in the formation of stable spatial structures, which have significant effects on community functioning, in agreement with experimental observations of pattern formation in microbial communities.
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Affiliation(s)
- Aisling J Daly
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, Ghent B-9000, Belgium
| | - Jan M Baetens
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, Ghent B-9000, Belgium
| | - Bernard De Baets
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, Ghent B-9000, Belgium
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28
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Holm SR, Noon BR, Wiens JD, Ripple WJ. Potential trophic cascades triggered by the barred owl range expansion. WILDLIFE SOC B 2016. [DOI: 10.1002/wsb.714] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Samantha R. Holm
- Department of Fish, Wildlife, and Conservation Biology and Graduate Degree Program in Ecology; Colorado State University; Fort Collins CO 80523 USA
| | - Barry R. Noon
- Department of Fish, Wildlife, and Conservation Biology and Graduate Degree Program in Ecology; Colorado State University; Fort Collins CO 80523 USA
| | - J. David Wiens
- U.S. Geological Survey, Forest and Range Ecosystem Science Center; 3200 SW Jefferson Way Corvallis OR 9733 USA
| | - William J. Ripple
- Trophic Cascades Program; Department of Forest Ecosystems and Society; Oregon State University; Corvallis OR 97331 USA
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29
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Diamond SE, Nichols LM, Pelini SL, Penick CA, Barber GW, Cahan SH, Dunn RR, Ellison AM, Sanders NJ, Gotelli NJ. Climatic warming destabilizes forest ant communities. SCIENCE ADVANCES 2016; 2:e1600842. [PMID: 27819044 PMCID: PMC5091351 DOI: 10.1126/sciadv.1600842] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 09/26/2016] [Indexed: 05/26/2023]
Abstract
How will ecological communities change in response to climate warming? Direct effects of temperature and indirect cascading effects of species interactions are already altering the structure of local communities, but the dynamics of community change are still poorly understood. We explore the cumulative effects of warming on the dynamics and turnover of forest ant communities that were warmed as part of a 5-year climate manipulation experiment at two sites in eastern North America. At the community level, warming consistently increased occupancy of nests and decreased extinction and nest abandonment. This consistency was largely driven by strong responses of a subset of thermophilic species at each site. As colonies of thermophilic species persisted in nests for longer periods of time under warmer temperatures, turnover was diminished, and species interactions were likely altered. We found that dynamical (Lyapunov) community stability decreased with warming both within and between sites. These results refute null expectations of simple temperature-driven increases in the activity and movement of thermophilic ectotherms. The reduction in stability under warming contrasts with the findings of previous studies that suggest resilience of species interactions to experimental and natural warming. In the face of warmer, no-analog climates, communities of the future may become increasingly fragile and unstable.
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Affiliation(s)
- Sarah E. Diamond
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Lauren M. Nichols
- Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695, USA
| | - Shannon L. Pelini
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH 43403, USA
| | - Clint A. Penick
- Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695, USA
| | - Grace W. Barber
- Department of Environmental Conservation, University of Massachusetts, Amherst, MA 01003, USA
- Harvard Forest, Harvard University, Petersham, MA 01366, USA
| | - Sara Helms Cahan
- Department of Biology, University of Vermont, Burlington, VT 05405, USA
| | - Robert R. Dunn
- Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695, USA
- Center for Macroecology, Evolution and Climate, University of Copenhagen, Copenhagen, DK-2100, Denmark
| | | | - Nathan J. Sanders
- Center for Macroecology, Evolution and Climate, University of Copenhagen, Copenhagen, DK-2100, Denmark
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Rohr JR, Salice CJ, Nisbet RM. The pros and cons of ecological risk assessment based on data from different levels of biological organization. Crit Rev Toxicol 2016; 46:756-84. [PMID: 27340745 PMCID: PMC5141515 DOI: 10.1080/10408444.2016.1190685] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 05/12/2016] [Accepted: 05/13/2016] [Indexed: 01/15/2023]
Abstract
Ecological risk assessment (ERA) is the process used to evaluate the safety of manufactured chemicals to the environment. Here we review the pros and cons of ERA across levels of biological organization, including suborganismal (e.g., biomarkers), individual, population, community, ecosystem and landscapes levels. Our review revealed that level of biological organization is often related negatively with ease at assessing cause-effect relationships, ease of high-throughput screening of large numbers of chemicals (it is especially easier for suborganismal endpoints), and uncertainty of the ERA because low levels of biological organization tend to have a large distance between their measurement (what is quantified) and assessment endpoints (what is to be protected). In contrast, level of biological organization is often related positively with sensitivity to important negative and positive feedbacks and context dependencies within biological systems, and ease at capturing recovery from adverse contaminant effects. Some endpoints did not show obvious trends across levels of biological organization, such as the use of vertebrate animals in chemical testing and ease at screening large numbers of species, and other factors lacked sufficient data across levels of biological organization, such as repeatability, variability, cost per study and cost per species of effects assessment, the latter of which might be a more defensible way to compare costs of ERAs than cost per study. To compensate for weaknesses of ERA at any particular level of biological organization, we also review mathematical modeling approaches commonly used to extrapolate effects across levels of organization. Finally, we provide recommendations for next generation ERA, submitting that if there is an ideal level of biological organization to conduct ERA, it will only emerge if ERA is approached simultaneously from the bottom of biological organization up as well as from the top down, all while employing mathematical modeling approaches where possible to enhance ERA. Because top-down ERA is unconventional, we also offer some suggestions for how it might be implemented efficaciously. We hope this review helps researchers in the field of ERA fill key information gaps and helps risk assessors identify the best levels of biological organization to conduct ERAs with differing goals.
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Affiliation(s)
| | | | - Roger M. Nisbet
- University of California at Santa Barbara, Santa Barbara, CA 93106-9620
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31
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Daly AJ, Baetens JM, De Baets B. In silico substrate dependence increases community productivity but threatens biodiversity. Phys Rev E 2016; 93:042414. [PMID: 27176336 DOI: 10.1103/physreve.93.042414] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Indexed: 11/07/2022]
Abstract
The critical role that biodiversity plays in ecosystem functioning has motivated many studies of the mechanisms that sustain biodiversity, a notable example being cyclic competition. We extend existing models of communities with cyclic competition by incorporating variable community evenness and resource dependence in demographic processes, two features that have generally been neglected. In this way, we align previous approaches more closely with real-world microbial ecosystems. We demonstrate the existence of a trade-off between increasing biomass production and maintaining biodiversity. This supports experimental observations of a net negative biodiversity effect on biomass productivity, due to competition effects suffered by highly productive species in diverse communities. Our results also support the important role assigned by microbial ecologists to evenness in maintaining ecosystem stability, thus far largely overlooked in in silico approaches.
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Affiliation(s)
- Aisling J Daly
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Jan M Baetens
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Bernard De Baets
- KERMIT, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
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32
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Colin N, Porte C, Fernandes D, Barata C, Padrós F, Carrassón M, Monroy M, Cano-Rocabayera O, de Sostoa A, Piña B, Maceda-Veiga A. Ecological relevance of biomarkers in monitoring studies of macro-invertebrates and fish in Mediterranean rivers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 540:307-323. [PMID: 26148426 DOI: 10.1016/j.scitotenv.2015.06.099] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/24/2015] [Accepted: 06/24/2015] [Indexed: 06/04/2023]
Abstract
Mediterranean rivers are probably one of the most singular and endangered ecosystems worldwide due to the presence of many endemic species and a long history of anthropogenic impacts. Besides a conservation value per se, biodiversity is related to the services that ecosystems provide to society and the ability of these to cope with stressors, including climate change. Using macro-invertebrates and fish as sentinel organisms, this overview presents a synthesis of the state of the art in the application of biomarkers (stress and enzymatic responses, endocrine disruptors, trophic tracers, energy and bile metabolites, genotoxic indicators, histopathological and behavioural alterations, and genetic and cutting edge omic markers) to determine the causes and effects of anthropogenic stressors on the biodiversity of European Mediterranean rivers. We also discuss how a careful selection of sentinel species according to their ecological traits and the food-web structure of Mediterranean rivers could increase the ecological relevance of biomarker responses. Further, we provide suggestions to better harmonise ecological realism with experimental design in biomarker studies, including statistical analyses, which may also deliver a more comprehensible message to managers and policy makers. By keeping on the safe side the health status of populations of multiple-species in a community, we advocate to increase the resilience of fluvial ecosystems to face present and forecasted stressors. In conclusion, this review provides evidence that multi-biomarker approaches detect early signs of impairment in populations, and supports their incorporation in the standardised procedures of the Water Frame Work Directive to better appraise the status of European water bodies.
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Affiliation(s)
- Nicole Colin
- Department of Animal Biology, Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain; Institute of Research in Biodiversity (IRBio), Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain.
| | - Cinta Porte
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), ES-08028 Barcelona, Spain
| | - Denise Fernandes
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), ES-08028 Barcelona, Spain
| | - Carlos Barata
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), ES-08028 Barcelona, Spain
| | - Francesc Padrós
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, ES-08193 Barcelona, Spain
| | - Maite Carrassón
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, ES-08193 Barcelona, Spain
| | - Mario Monroy
- Department of Animal Biology, Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain; Institute of Research in Biodiversity (IRBio), Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain
| | - Oriol Cano-Rocabayera
- Department of Animal Biology, Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain; Institute of Research in Biodiversity (IRBio), Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain
| | - Adolfo de Sostoa
- Department of Animal Biology, Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain; Institute of Research in Biodiversity (IRBio), Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain
| | - Benjamín Piña
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), ES-08028 Barcelona, Spain
| | - Alberto Maceda-Veiga
- Institute of Research in Biodiversity (IRBio), Faculty of Biology, University of Barcelona, ES-08028 Barcelona, Spain; School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK; Department of Integrative Ecology, Estación Biológica de Doñana (EBD-CSIC), Estación Biológica de Doñana (EBD-CSIC), ES-41092 Sevilla, Spain
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33
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Jonsson T, Berg S, Emmerson M, Pimenov A. The context dependency of species keystone status during food web disassembly. FOOD WEBS 2015. [DOI: 10.1016/j.fooweb.2015.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Daly AJ, Baetens JM, De Baets B. The impact of initial evenness on biodiversity maintenance for a four-species in silico bacterial community. J Theor Biol 2015; 387:189-205. [DOI: 10.1016/j.jtbi.2015.09.036] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/15/2015] [Accepted: 09/29/2015] [Indexed: 10/22/2022]
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Sekar N, Lee CL, Sukumar R. In the elephant's seed shadow: the prospects of domestic bovids as replacement dispersers of three tropical Asian trees. Ecology 2015; 96:2093-105. [PMID: 26405735 DOI: 10.1890/14-1543.1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
As populations of the world's largest animal species decline, it is unclear how ecosystems will react to their local extirpation. Due to the unique ecological characteristics of megaherbivores such as elephants, seed dispersal is one ecosystem process that may be affected as populations of large animals are decimated. In typically disturbed South Asian ecosystems, domestic bovids (cattle, Bosprimigenius, and buffalo, Bubalus bubalis) may often be the species most available to replace Asian elephants (Elephas maximus) as endozoochorous dispersers of large-fruited mammal-dispersed species. We use feeding trials, germination trials, and movement data from the tropical moist forests of Buxa Tiger Reserve (India) to examine whether domestic bovids are viable replacements for elephants in the dispersal of three large- fruited species: Dillenia indica, Artocarpus chaplasha, and Careya arborea. We find that (1) once consumed, seeds are between 2.5 (C. arborea) and 26.5 (D. indica) times more likely to pass undigested into elephant dung than domestic bovid dung; and (2) seeds from elephant dung germinated as well as or better than seeds taken from bovid dung for all plant species, with D. indica seeds from elephant dung 1.5 times more likely to germinate. Furthermore, since wild elephants have less constrained movements than even free-roaming domestic bovids, we calculate that maximum dispersal by elephants is between 9.5 and 11.2 times farther than that of domestic bovids, with about 20% of elephant-dispersed seeds being moved farther than the maximum distance seeds are moved by bovids. Our findings suggest that, while bovids are able to disperse substantial numbers of seeds over moderate distances for two of the three study species, domestic bovids will be unable to routinely emulate the reliable, long-distance dispersal of seeds executed by elephants in this tropical moist forest. Thus while domestic bovids can attenuate the effects of losing elephants as dispersers, they may not be able to prevent the decline of various mammal-dispersed fruiting species in the face of overhunting, habitat fragmentation, and climate change.
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36
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Hartley SE, Green JP, Massey FP, Press MCP, Stewart AJA, John EA. Hemiparasitic plant impacts animal and plant communities across four trophic levels. Ecology 2015; 96:2408-16. [DOI: 10.1890/14-1244.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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37
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Ballantyne M, Pickering CM. Recreational trails as a source of negative impacts on the persistence of keystone species and facilitation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 159:48-57. [PMID: 26042631 DOI: 10.1016/j.jenvman.2015.05.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 05/18/2015] [Accepted: 05/20/2015] [Indexed: 06/04/2023]
Abstract
Hiking trails, which are among the most common forms of infrastructure created for nature-based tourism, can alter key ecological processes. Trails can damage plants that facilitate the establishment and growth of other species leading to changes in community and functional composition. This can be a particular concern in harsh alpine ecosystems where plant communities are often dominated by one or two keystone species that provide shelter to a suite of beneficiary species. We analysed how a hiking trail affects interspecific facilitation by a dominant trampling-sensitive nurse shrub in the highest National Park in Australia. First we assessed the effects of the trail on the abundance, size and density of the nurse shrub at different distances from the trail. We then compared species richness and composition between areas in, and out, of the nurse shrub's canopy at different distances from the trail. To better understand why some species may benefit from facilitation and any effects of the trail on the quality of facilitation we compared functional composition between quadrats using community trait weighted means calculated by combining plant composition with species functional traits (canopy height, leaf area, % dry weight of leaves and specific leaf area). The abundance, size and density of nurse shrubs was lower on the trail edges than further away, particularly on the leeward edge, where there was more bare ground and less shrub cover. There were differences in species richness, cover, composition and functional composition in and outside the nurse shrub canopy. The shrubs appeared to facilitate species with more competitive, but less stress tolerant traits (e.g. taller plants with leaves that were larger, had high specific leaf area and low dry matter content). However, despite reductions in nurse shrubs near the trail, where they do exist, they appear to provide the same 'quality' of facilitation as nurse shrubs further away. However, longer-term effects may be occurring as the loss of nurse shrubs alters the wind profile of the ridgeline and therefore succession. The use of a steel mesh walkway along the trail may facilitate the regeneration of nurse shrubs and other plants that require protection from wind. Our results highlight the importance of diversifying recreation ecology research to assess how trails affect important ecological processes.
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Affiliation(s)
- Mark Ballantyne
- Environmental Futures Research Institute, Griffith University, Gold Coast, Queensland, 4222, Australia.
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38
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Scotti M, Jordán F. The structural importance of less abundant species in Prince William Sound food web. Isr J Ecol Evol 2015. [DOI: 10.1080/15659801.2015.1067972] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Rarity of species is often considered to set priorities for biodiversity conservation. Less abundant species are expected to be at higher risk of extinction and make significant contribution to food web functioning. However, the relationship between species abundance and position in food webs is still unclear. Here we tested possible correlations between species abundance and structural position in Prince William Sound food web. Species abundance was inferred from biomass data and structural position was characterized by 13 centrality indices.We found that less abundant species have higher trophic positions and display more generalist feeding strategies. However, positive correlations link most of the centrality indices to population size. Thus, being locally rare translates into more peripheral food web positions and implies marginal roles in the spread of indirect effects. Species characterized by largest population size are responsible for the transfer of largest amounts of biomass and regulate the transmission of indirect effects. Less abundant species are of marginal structural importance and are exposed to impacts mediated by larger populations. In Prince William Sound ecosystem, rarity is associated with critical food web positions and does not simply reflect a marginal contribution to biodiversity.We suggest that knowing the food web position of rare species might help to formulate more effective, system-level solutions for their conservation, rather than simply focusing on the direct treatment of symptoms.
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Affiliation(s)
- Marco Scotti
- GEOMAR Helmholtz Centre for Ocean Research, , Marine Ecology Division, Research Unit Experimental Ecology
| | - Ferenc Jordán
- Danube Research Institute, Centre for Ecological Research, Hungarian Academy of Sciences
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39
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Valls A, Coll M, Christensen V. Keystone species: toward an operational concept for marine biodiversity conservation. ECOL MONOGR 2015. [DOI: 10.1890/14-0306.1] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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40
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Analysis and Control of Pre-extinction Dynamics in Stochastic Populations. Bull Math Biol 2014; 76:3122-37. [DOI: 10.1007/s11538-014-0047-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 11/11/2014] [Indexed: 10/24/2022]
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41
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Brodie JF, Aslan CE, Rogers HS, Redford KH, Maron JL, Bronstein JL, Groves CR. Secondary extinctions of biodiversity. Trends Ecol Evol 2014; 29:664-72. [PMID: 25445878 DOI: 10.1016/j.tree.2014.09.012] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 09/25/2014] [Accepted: 09/26/2014] [Indexed: 10/24/2022]
Abstract
Extinctions beget further extinctions when species lose obligate mutualists, predators, prey, or hosts. Here, we develop a conceptual model of species and community attributes affecting secondary extinction likelihood, incorporating mechanisms that buffer organisms against partner loss. Specialized interactors, including 'cryptic specialists' with diverse but nonredundant partner assemblages, incur elevated risk. Risk is also higher for species that cannot either evolve new traits following partner loss or obtain novel partners in communities reorganizing under changing environmental conditions. Partner loss occurs alongside other anthropogenic impacts; multiple stressors can circumvent ecological buffers, enhancing secondary extinction risk. Stressors can also offset each other, reducing secondary extinction risk, a hitherto unappreciated phenomenon. This synthesis suggests improved conservation planning tactics and critical directions for research on secondary extinctions.
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Affiliation(s)
- Jedediah F Brodie
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada; Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada; Biodiversity Research Centre, University of British Columbia, Vancouver BC, V6T 1Z4, Canada.
| | - Clare E Aslan
- Conservation Education and Science Department, Arizona-Sonora Desert Museum, Tucson, AZ 85743, USA
| | - Haldre S Rogers
- Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA
| | | | - John L Maron
- Division of Biological Sciences, University of Montana, Missoula, MT 59803, USA
| | - Judith L Bronstein
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
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42
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Berg S, Pimenov A, Palmer C, Emmerson M, Jonsson T. Ecological communities are vulnerable to realistic extinction sequences. OIKOS 2014. [DOI: 10.1111/oik.01279] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sofia Berg
- Dept of Physics, Chemistry and Biology, Div. of Theoretical Biology; Linköping Univ.; SE-58183 Linköping Sweden
- Research Centre for Systems Biology, Univ. of Skövde; PO Box 408, SE-541 28 Skövde Sweden
| | - Alexander Pimenov
- Weierstrass Inst.; Mohrenstr. 39 DE-10117 Berlin Germany
- Environmental Research Inst., Univ. College Cork; Lee Road Cork Ireland
| | | | - Mark Emmerson
- School of Biological Sciences, Queen's Univ. Belfast; 97 Lisburn Road Belfast BT9 7BL UK
| | - Tomas Jonsson
- Research Centre for Systems Biology, Univ. of Skövde; PO Box 408, SE-541 28 Skövde Sweden
- Dept of Ecology; Swedish Univ. of Agricultural Sciences; Box 7044, SE-750 07 Uppsala Sweden
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43
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Jonsson T, Berg S, Pimenov A, Palmer C, Emmerson M. The reliability ofR50as a measure of vulnerability of food webs to sequential species deletions. OIKOS 2014. [DOI: 10.1111/oik.01588] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Tomas Jonsson
- Dept of Ecology; Swedish Univ. of Agricultural Sciences; Box 7044, SE-750 07 Uppsala Sweden
- Research Centre for Systems Biology, Univ. of Skövde; PO Box 408, SE-541 28 Skövde Sweden
| | - Sofia Berg
- Research Centre for Systems Biology, Univ. of Skövde; PO Box 408, SE-541 28 Skövde Sweden
- Dept of Physics, Chemistry and Biology, Div. of Theoretical Biology; Linköping Univ.; SE-58183 Linköping Sweden
| | - Alexander Pimenov
- Environmental Res. Inst., Univ. College Cork; Lee Road Cork Ireland
- Weierstrass Inst.; Mohrenstr. 39 DE-10117 Berlin Germany
| | - Catherine Palmer
- Environmental Res. Inst., Univ. College Cork; Lee Road Cork Ireland
| | - Mark Emmerson
- School of Biological Sciences, Queen's Univ. Belfast; 97 Lisburn Road Belfast BT9 7BL UK
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44
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Barabás G, Pásztor L, Meszéna G, Ostling A. Sensitivity analysis of coexistence in ecological communities: theory and application. Ecol Lett 2014; 17:1479-94. [DOI: 10.1111/ele.12350] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 04/18/2014] [Accepted: 08/01/2014] [Indexed: 11/29/2022]
Affiliation(s)
- György Barabás
- Department of Ecology and Evolution; University of Chicago; 1101 E 57th St Chicago IL 60637 USA
| | - Liz Pásztor
- Department of Genetics; Eötvös Loránd University; Pázmány Péter sétány 1C H-1117 Budapest Hungary
| | - Géza Meszéna
- Department of Biological Physics; Eötvös Loránd University; Pázmány Péter sétány 1A H-1117 Budapest Hungary
| | - Annette Ostling
- Department of Ecology and Evolutionary Biology; University of Michigan; 830 North University Ann Arbor MI 48109-1048 USA
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45
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Microbiota dynamics in patients treated with fecal microbiota transplantation for recurrent Clostridium difficile infection. PLoS One 2013; 8:e81330. [PMID: 24303043 PMCID: PMC3841263 DOI: 10.1371/journal.pone.0081330] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/20/2013] [Indexed: 12/14/2022] Open
Abstract
Clostridium difficile causes antibiotic-associated diarrhea and pseudomembraneous colitis and is responsible for a large and increasing fraction of hospital-acquired infections. Fecal microbiota transplantation (FMT) is an alternate treatment option for recurrent C. difficile infection (RCDI) refractory to antibiotic therapy. It has recently been discussed favorably in the clinical and scientific communities and is receiving increasing public attention. However, short- and long-term health consequences of FMT remain a concern, as the effects of the transplanted microbiota on the patient remain unknown. To shed light on microbial events associated with RCDI and treatment by FMT, we performed fecal microbiota analysis by 16S rRNA gene amplicon pyrosequencing of 14 pairs of healthy donors and RCDI patients treated successfully by FMT. Post-FMT patient and healthy donor samples collected up to one year after FMT were studied longitudinally, including one post-FMT patient with antibiotic-associated relapse three months after FMT. This analysis allowed us not only to confirm prior reports that RCDI is associated with reduced diversity and compositional changes in the fecal microbiota, but also to characterize previously undocumented post-FMT microbiota dynamics. Members of the Streptococcaceae, Enterococcaceae, or Enterobacteriaceae were significantly increased and putative butyrate producers, such as Lachnospiraceae and Ruminococcaceae were significantly reduced in samples from RCDI patients before FMT as compared to post-FMT patient and healthy donor samples. RCDI patient samples showed more case-specific variations than post-FMT patient and healthy donor samples. However, none of the bacterial groups were invariably associated with RCDI or successful treatment by FMT. Overall microbiota compositions in post-FMT patients, specifically abundances of the above-mentioned Firmicutes, continued to change for at least 16 weeks after FMT, suggesting that full microbiota recovery from RCDI may take much longer than expected based on the disappearance of diarrheal symptoms immediately after FMT.
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46
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Lin Y, Sutherland WJ. Color and degree of interspecific synchrony of environmental noise affect the variability of complex ecological networks. Ecol Modell 2013. [DOI: 10.1016/j.ecolmodel.2013.05.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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47
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High frequency of functional extinctions in ecological networks. Nature 2013; 499:468-70. [PMID: 23831648 DOI: 10.1038/nature12277] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 05/09/2013] [Indexed: 11/08/2022]
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48
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Eklöf A, Tang S, Allesina S. Secondary extinctions in food webs: a Bayesian network approach. Methods Ecol Evol 2013. [DOI: 10.1111/2041-210x.12062] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Anna Eklöf
- Department of Ecology & Evolution; University of Chicago; Chicago; IL; USA
| | - Si Tang
- Department of Ecology & Evolution; University of Chicago; Chicago; IL; USA
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49
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Fowler MS. The form of direct interspecific competition modifies secondary extinction patterns in multi-trophic food webs. OIKOS 2013. [DOI: 10.1111/j.1600-0706.2013.00346.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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Eklöf A, Kaneryd L, Münger P. Climate change in metacommunities: dispersal gives double-sided effects on persistence. Philos Trans R Soc Lond B Biol Sci 2013; 367:2945-54. [PMID: 23007082 DOI: 10.1098/rstb.2012.0234] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Climate change is increasingly affecting the structure and dynamics of ecological communities both at local and at regional scales, and this can be expected to have important consequences for their robustness and long-term persistence. The aim of the present work is to analyse how the spatial structure of the landscape and dispersal patterns of species (dispersal rate and average dispersal distance) affects metacommunity response to two disturbances: (i) increased mortality during dispersal and (ii) local species extinction. We analyse the disturbances both in isolation and in combination. Using a spatially and dynamically explicit metacommunity model, we find that the effect of dispersal on metacommunity persistence is two-sided: on the one hand, high dispersal significantly reduces the risk of bottom-up extinction cascades following the local removal of a species; on the other hand, when dispersal imposes a risk to the dispersing individuals, high dispersal increases extinction risks, especially when dispersal is global. Large-bodied species with long generation times at the highest trophic level are particularly vulnerable to extinction when dispersal involves a risk. This suggests that decreasing the mortality risk of dispersing individuals by improving the quality of the habitat matrix may greatly increase the robustness of metacommunities.
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Affiliation(s)
- Anna Eklöf
- IFM, Theory and Modeling, Division of Theoretical Biology, Linköping University, 581 83 Linköping, Sweden.
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