Positive Effects of Bacterial Diversity on Ecosystem Functioning Driven by Complementarity Effects in a Bioremediation Context

The tree of life, describing the evolutionary relationships among organisms, is totally dominated by bacteria. In a regular ecology textbook, the number of bacterial and Archaeal examples are, however, few. Microorganisms are in many respects understudied, and we do not yet know if they follow similar “rules” as other organisms: for instance, regarding patterns in diversity over time and space. Further, bacteria play important roles in biogeochemical cycles, and therefore it is also important to understand if and how this enormous diversity is related to the role bacteria play in ecosystems. Despite methodological developments (see Historical Overview and Methods) that led to an exponential increase in the amount of data over time, we are still only scratching the surface of the diversity of freshwater bacteria (see Measuring Alpha Diversity), and few general patterns in diversity have emerged. Some typical freshwater bacterial groups have been identified (see Marine and Freshwater Bacterioplankton and Typical Freshwater Bacteria) and some important environmental steering factors are known (see Biogeography of Freshwater Bacteria). Further, a consistent pattern appears to be that alpha diversity decreases along lake and river chains because of inoculation of bacteria from species-rich soils (see Patterns in Alpha Diversity). Some findings of bacterial alpha diversity further indicate that bacterial diversity may not always follow the same rules as in larger organisms, challenging some established textbook “truths” regarding what is influencing diversity in general. But more data is needed for certain conclusions. Future work should also include the identification of the true (active) players and their possible importance for ecosystem functioning (see Identifying Contributors to Community Functioning).

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Impact of Temperature, Nutrients and Heavy Metals on Bacterial Diversity and Ecosystem Functioning Studied by Freshwater Microcosms and High-Throughput DNA Sequencing

Current Microbiology ◽

10.1007/s00284-020-02138-5 ◽

2020 ◽

Vol 77 (11) ◽

pp. 3512-3525

Author(s):

Tianma Yuan ◽

Alan J. McCarthy ◽

Yixin Zhang ◽

Raju Sekar

Keyword(s):

Heavy Metals ◽

Dna Sequencing ◽

Bacterial Diversity ◽

High Throughput ◽

Ecosystem Functioning ◽

High Throughput Dna Sequencing

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The up-scaling of ecosystem functions in a heterogeneous world

Scientific Reports ◽

10.1038/srep10349 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 22

Author(s):

Andrew M. Lohrer ◽

Simon F. Thrush ◽

Judi E. Hewitt ◽

Casper Kraan

Keyword(s):

Primary Productivity ◽

Ecosystem Functioning ◽

Large Scale ◽

Net Primary Productivity ◽

Marine Ecosystem ◽

Ecosystem Functions ◽

Small Scale ◽

Biodiversity Crisis ◽

Positive Effects ◽

Marine Habitats

Abstract Earth is in the midst of a biodiversity crisis that is impacting the functioning of ecosystems and the delivery of valued goods and services. However, the implications of large scale species losses are often inferred from small scale ecosystem functioning experiments with little knowledge of how the dominant drivers of functioning shift across scales. Here, by integrating observational and manipulative experimental field data, we reveal scale-dependent influences on primary productivity in shallow marine habitats, thus demonstrating the scalability of complex ecological relationships contributing to coastal marine ecosystem functioning. Positive effects of key consumers (burrowing urchins, Echinocardium cordatum) on seafloor net primary productivity (NPP) elucidated by short-term, single-site experiments persisted across multiple sites and years. Additional experimentation illustrated how these effects amplified over time, resulting in greater primary producer biomass (sediment chlorophyll a content) in the longer term, depending on climatic context and habitat factors affecting the strengths of mutually reinforcing feedbacks. The remarkable coherence of results from small and large scales is evidence of real-world ecosystem function scalability and ecological self-organisation. This discovery provides greater insights into the range of responses to broad-scale anthropogenic stressors in naturally heterogeneous environmental settings.

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Solar salterns as model systems to study the units of bacterial diversity that matter for ecosystem functioning

Current Opinion in Biotechnology ◽

10.1016/j.copbio.2021.07.028 ◽

2022 ◽

Vol 73 ◽

pp. 151-157

Author(s):

Konstantinos T Konstantinidis ◽

Tomeu Viver ◽

Roth E Conrad ◽

Stephanus N Venter ◽

Ramon Rossello-Mora

Keyword(s):

Bacterial Diversity ◽

Ecosystem Functioning ◽

Model Systems ◽

Solar Salterns

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An invasive plant species enhances biodiversity in overgrazed pastures but inhibits its recovery in protected areas

10.1101/2020.08.16.227066 ◽

2020 ◽

Author(s):

Gianalberto Losapio ◽

Consuelo M. De Moraes ◽

Rodolfo Dirzo ◽

Lilian L. Dutoit ◽

Thomas Tscheulin ◽

...

Keyword(s):

Plant Species ◽

Ecosystem Functioning ◽

Invasive Plant ◽

Prolonged Exposure ◽

Human Action ◽

Community Diversity ◽

Interactive Effects ◽

Species Invasion ◽

Biological Communities ◽

Positive Effects

AbstractAnthropogenic environmental change exposes biological communities to concurrent stressors (e.g., changes in climate and land-use, overexploitation, biotic invasions) that frequently persist over prolonged periods. Predicting and mitigating the consequences of human action on nature therefore requires understanding how exposure to multiple interacting stressors alters biological communities over relevant (e.g., multi-decadal) time periods. Here, we explore the effects of overgrazing and plant species invasion on plant community diversity and ecosystem functioning (productivity), as well as the patterns of recovery of plant communities following cessation of grazing pressure. In a Mediterranean pasture system, we utilized a “natural” experiment involving long-term exclusion of grazers (for 15-25 years in parks) and also conducted short-term grazing-exclusion and invasive species removal experiments. Our results reveal that invasion by a grazing-resistant plant (prickly burnet) has net positive effects on plant diversity under overgrazing conditions but inhibits the recovery of biodiversity once grazing ceases. Furthermore, while the diversity-productivity relationship was found to be positive in pastures, the interactive effects of overgrazing and species invasion appear to disrupt ecosystem functioning and inhibit the recovery of pasture productivity. These findings highlight the potential for prolonged exposure to anthropogenic stressors, such as overgrazing, to cause potentially-irreversible changes in biological communities that, in turn, compromise ecosystem functioning and resilience. In such cases, sustainable ecosystem management may require direct intervention to boost biodiversity resilience against centennial overgrazing.

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Predation increases multiple components of microbial diversity in activated sludge communities

The ISME Journal ◽

10.1038/s41396-021-01145-z ◽

2021 ◽

Author(s):

Alfred Burian ◽

Daisy Pinn ◽

Ignacio Peralta-Maraver ◽

Michael Sweet ◽

Quentin Mauvisseau ◽

...

Keyword(s):

Activated Sludge ◽

Microbial Diversity ◽

Bacterial Diversity ◽

Bacterial Communities ◽

Ecosystem Functioning ◽

Predation Pressure ◽

Treatment Efficiency ◽

Taxa Richness ◽

Multiple Components ◽

The Impact

AbstractProtozoan predators form an essential component of activated sludge communities that is tightly linked to wastewater treatment efficiency. Nonetheless, very little is known how protozoan predation is channelled via bacterial communities to affect ecosystem functioning. Therefore, we experimentally manipulated protozoan predation pressure in activated-sludge communities to determine its impacts on microbial diversity, composition and putative functionality. Different components of bacterial diversity such as taxa richness, evenness, genetic diversity and beta diversity all responded strongly and positively to high protozoan predation pressure. These responses were non-linear and levelled off at higher levels of predation pressure, supporting predictions of hump-shaped relationships between predation pressure and prey diversity. In contrast to predation intensity, the impact of predator diversity had both positive (taxa richness) and negative (evenness and phylogenetic distinctiveness) effects on bacterial diversity. Furthermore, predation shaped the structure of bacterial communities. Reduction in top-down control negatively affected the majority of taxa that are generally associated with increased treatment efficiency, compromising particularly the potential for nitrogen removal. Consequently, our findings highlight responses of bacterial diversity and community composition as two distinct mechanisms linking protozoan predation with ecosystem functioning in activated sludge communities.

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Historical Nitrogen Deposition and Straw Addition Facilitate the Resistance of Soil Multifunctionality to Drying-Wetting Cycles

Applied and Environmental Microbiology ◽

10.1128/aem.02251-18 ◽

2019 ◽

Vol 85 (8) ◽

Cited By ~ 5

Author(s):

Gongwen Luo ◽

Tingting Wang ◽

Kaisong Li ◽

Ling Li ◽

Junwei Zhang ◽

...

Keyword(s):

Climate Change ◽

Microbial Communities ◽

Functional Capacity ◽

Ecosystem Functioning ◽

Cellulose Degradation ◽

Soil Microbial Communities ◽

Equation Modeling ◽

Organic C ◽

Soil Microbial ◽

Positive Effects

ABSTRACT Climate change is predicted to alter precipitation and drought patterns, which has become a global concern as evidence accumulates that it will affect ecosystem services. Disentangling the ability of soil multifunctionality to withstand this stress (multifunctionality resistance) is a crucial topic for assessing the stability and adaptability of agroecosystems. In this study, we explored the effects of nutrient addition on multifunctionality resistance to drying-wetting cycles and evaluated the importance of microbial functional capacity (characterized by the abundances of genes involved in carbon, nitrogen and phosphorus cycles) for this resistance. The multifunctionality of soils treated with nitrogen (N) and straw showed a higher resistance to drying-wetting cycles than did nonamended soils. Microbial functional capacity displayed a positive linear relationship with multifunctionality resistance. Random forest analysis showed that the abundances of the archeal amoA (associated with nitrification) and nosZ and narG (denitrification) genes were major predictors of multifunctionality resistance in soils without straw addition. In contrast, major predictors of multifunctionality resistance in straw amended soils were the abundances of the GH51 (xylan degradation) and fungcbhIF (cellulose degradation) genes. Structural equation modeling further demonstrated the large direct contribution of carbon (C) and N cycling-related gene abundances to multifunctionality resistance. The modeling further elucidated the positive effects of microbial functional capacity on this resistance, which was mediated potentially by a high soil fungus/bacterium ratio, dissolved organic C content, and low pH. The present work suggests that nutrient management of agroecosystems can buffer negative impacts on ecosystem functioning caused by a climate change-associated increase in drying-wetting cycles via enriching functional capacity of microbial communities. IMPORTANCE Current climate trends indicate an increasing frequency of drying-wetting cycles. Such cycles are severe environmental perturbations and have received an enormous amount of attention. Prediction of ecosystem’s stability and adaptability requires a better mechanistic understanding of the responses of microbially mediated C and nutrient cycling processes to external disturbance. Assessment of this stability and adaptability further need to disentangle the relationships between functional capacity of soil microbial communities and the resistance of multifunctionality. Study of the physiological responses and community reorganization of soil microbes in response to stresses requires large investments of resources that vary with the management history of the system. Our study provides evidence that nutrient managements on agroecosystems can be expected to buffer the impacts of progressive climate change on ecosystem functioning by enhancing the functional capacity of soil microbial communities, which can serve as a basis for field studies.

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Phytoplankton Diversity Effect on Ecosystem Functioning in a Coastal Upwelling System

Frontiers in Marine Science ◽

10.3389/fmars.2020.592255 ◽

2020 ◽

Vol 7 ◽

Author(s):

Jaime Otero ◽

Xosé Antón Álvarez-Salgado ◽

Antonio Bode

Keyword(s):

Functional Diversity ◽

Ecosystem Functioning ◽

Coastal Upwelling ◽

Explanatory Power ◽

Taxonomic Diversity ◽

Least Square ◽

Trophic Levels ◽

Phytoplankton Diversity ◽

Positive Effects ◽

Upwelling System

Species composition plays a key role in ecosystem functioning. Theoretical, experimental and field studies show positive effects of biodiversity on ecosystem processes. However, this link can differ between taxonomic and functional diversity components and also across trophic levels. These relationships have been hardly studied in planktonic communities of coastal upwelling systems. Using a 28-year time series of phytoplankton and zooplankton assemblages, we examined the effects of phytoplankton diversity on resource use efficiency (RUE, ratio of biomass to limiting resource) at the two trophic levels in the Galician upwelling system (NW Iberian peninsula). By fitting generalized least square models, we show that phytoplankton diversity was the best predictor for RUE across planktonic trophic levels. This link varied depending on the biodiversity component considered: while the effect of phytoplankton richness on RUE was positive for phytoplankton RUE and negative for zooplankton RUE, phytoplankton evenness effect was negative for phytoplankton RUE and positive for zooplankton RUE. Overall, taxonomic diversity had higher explanatory power than functional diversity, and variability in phytoplankton and zooplankton RUE decreased with increasing phytoplankton taxonomic diversity. Phytoplankton used resources more efficiently in warmer waters and at greater upwelling intensity, although these effects were not as strong as those for biodiversity. These results suggest that phytoplankton species numbers in highly dynamic upwelling systems are important for maintaining the planktonic biomass production leading us to hypothesize the relevance of complementarity effects. However, we further postulate that a selection effect may operate also because assemblages with low evenness were dominated by diatoms with specific functional traits increasing their ability to exploit resources more efficiently.

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