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Results for “Community assembly”

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PubMed2006

Potential role of natural enemies during tree range expansions following climate change.

Recent investigations have shown how chance, long-range dispersal events can allow tree populations to migrate rapidly in response to changes in climate. However, this apparent solution to Reid's paradox applies solely within the context of single species models, while the rapid migration rates seen in pollen records occurred within multispecies communities. Ecologists are therefore presented with a new challenge: reconciling the macroscopic dynamics of spread seen in the pollen record with the rules and interactions governing plant community assembly. A case that highlights this issue is the rapid spread of Beech during the Holocene into a landscape already dominated by a close competitor, Hemlock. In this study, we analyse a simple model of plant community assembly incorporating competition for space and dispersal dynamics, showing how, even when a species is capable of rapid migration into an empty landscape, the presence of an ecologically similar competitor causes Reid's paradox to re-emerge because of the dramatic slowing effect of competitive interactions on a species' rate of spread. We then show how the answer to the question of how tree species dispersed rapidly into occupied landscapes may lie in secondary interactions with host-specific pathogens and parasites. Inclusion of host-specific pathogens into the simple community assembly model illustrates how tree species undergoing range expansions can temporarily outstrip specialist predators, giving rise to a transient Jansen-Connell effect, in which the invader acts as temporary 'super-species' that spreads rapidly into communities already occupied by competitors at rates consistent with those observed in the paleo-record.

Ecosystem↗

PubMed2019

Dietary iron variably modulates assembly of the intestinal microbiota in colitis-resistant and colitis-susceptible mice.

Iron deficiency, a common comorbidity of gastrointestinal inflammatory disorders such as inflammatory bowel diseases (IBD), is often treated with oral iron supplementation. However, the safety of oral iron supplementation remains controversial because of its association with exacerbated disease activity in a subset of IBD patients. Because iron modulates bacterial growth and function, one possible mechanism by which iron may exacerbate inflammation in susceptible hosts is by modulating the intestinal microbiota. We, therefore, investigated the impact of dietary iron on the intestinal microbiota, utilizing the conventionalization of germ-free mice as a model of a microbial community in compositional flux to recapitulate the instability of the IBD-associated intestinal microbiota. Our findings demonstrate that altering intestinal iron availability during community assembly modulated the microbiota in non-inflamed wild type (WT) and colitis-susceptible interleukin-10-deficient (Il10-/-) mice. Depletion of luminal iron availability promoted luminal compositional changes associated with dysbiotic states irrespective of host genotype, including an expansion of Enterobacteriaceae such as Escherichia coli. Mechanistic in vitro growth competitions confirmed that high-affinity iron acquisition systems in E. coli enhance its abundance over other bacteria in iron-restricted conditions, thereby enabling pathobiont iron scavenging during dietary iron restriction. In contrast, distinct luminal community assembly was observed with dietary iron supplementation in WT versus Il10-/- mice, suggesting that the effects of increased iron on the microbiota differ with host inflammation status. Taken together, shifts in dietary iron intake during community assembly modulate the ecological structure of the intestinal microbiota and is dependent on host genotype and inflammation status.

Animals↗

PubMed2026

Metagenomic Insights into Microbial Assembly and Key Metabolic Genes Driving Flavor Formation in Spontaneously Fermented Zhejiang Rosy Vinegar.

The spontaneous fermentation of Zhejiang rosy vinegar (ZRV) is driven by environmental microbiota, but the processes underlying its flavor formation remain poorly understood. Using metagenomic sequencing, we investigated microbial community assembly, environmental drivers, and metabolic networks during industrial-scale ZRV fermentation. Acetic acid dominated the final organic acids. Community assembly shifted toward deterministic selection with rising acidity, with a slight rebound of stochastic processes in the late stage (R2 values of 0.442 and 0.346 for bacteria and fungi, respectively). Mantel tests confirmed that environmental factors significantly regulated microbial assembly. Co-occurrence networks grew more complex, with positive interactions accounting for 85.24% (bacteria) and 90.10% (fungi) in the late stage. Key genes (ldh, gapA, pgk) from Acetobacter pasteurianus and Lactobacillus acetotolerans dominated late-stage fermentation, while genes (adhP, SDH) from Aspergillus oryzae and Saccharomyces cerevisiae supported early- and mid-stage fermentation. These findings elucidate microbiota-driven metabolic pathways in ZRV, supporting the fermentation window optimization and industrial vinegar quality standardization.

Acetic Acid↗

PubMed2006

In search of quorum effects in metacommunity structure: species co-occurrence analyses.

Alternative models of community assembly emphasize regional, stochastic, dispersal-based processes or local, deterministic, niche-based processes. Community ecology's historical focus on local processes implicitly assumes that local processes surpass regional processes over time or across space to derive nonrandom metacommunity structure (i.e., a quorum effect). Quorum effects are expected late in succession among nearby sites, whereas quorum effects are not expected early in succession among distant sites. I conducted a meta-analysis of zooplankton data sets encompassing time scales of one to thousands of years and spatial scales of <1 m to thousands of kilometers. Species co-occurrence analyses statistically evaluated presence/absence patterns relative to random patterns obtained with Monte Carlo null models. A series of weighted analyses was conducted and alternative randomization algorithms and null models were evaluated. Most zooplankton metacommunities were randomly structured in unweighted analyses, and the distribution of significant structure did not follow quorum effect predictions. Weighted analyses (e.g., by habitat area) revealed significant, nonrandom structure in most zooplankton metacommunities, but the distribution of significant structure still did not adhere well to quorum effect predictions. Finally, additional weighting for study scale (number of sites) nullified most significant area-weighted structure, and again, the distribution of significant structure did not follow quorum effect predictions. Overall, a quorum effect was not supported, perhaps related to zooplankton life histories and energetics and/or the quorum effect itself. Results at the presence/absence level of resolution indicated that local processes did not generally override regional processes over time or across space to drive community structure. A full integration of dispersal- and niche-based concepts in metacommunity dynamics will be most fruitful for unraveling community assembly. Species co-occurrence analyses were scale dependent (habitat area and study size). Future analyses should use weights for important factors (e.g., habitat area), and meta-analyses should include study scale as an additional factor contributing to apparent patterns.

Animals↗

PubMed2004

Recovery of frog and lizard communities following primary habitat alteration in Mizoram, Northeast India.

BACKGROUND: Community recovery following primary habitat alteration can provide tests for various hypotheses in ecology and conservation biology. Prominent among these are questions related to the manner and rate of community assembly after habitat perturbation. Here we use space-for-time substitution to analyse frog and lizard community assembly along two gradients of habitat recovery following slash and burn agriculture (jhum) in Mizoram, Northeast India. One recovery gradient undergoes natural succession to mature tropical rainforest, while the other involves plantation of jhum fallows with teak Tectona grandis monoculture. RESULTS: Frog and lizard communities accumulated species steadily during natural succession, attaining characteristics similar to those from mature forest after 30 years of regeneration. Lizards showed higher turnover and lower augmentation of species relative to frogs. Niche based classification identified a number of guilds, some of which contained both frogs and lizards. Successional change in species richness was due to increase in the number of guilds as well as the number of species per guild. Phylogenetic structure increased with succession for some guilds. Communities along the teak plantation gradient on the other hand, did not show any sign of change with chronosere age. Factor analysis revealed sets of habitat variables that independently determined changes in community and guild composition during habitat recovery. CONCLUSIONS: The timescale of frog and lizard community recovery was comparable with that reported by previous studies on different faunal groups in other tropical regions. Both communities converged on primary habitat attributes during natural vegetation succession, the recovery being driven by deterministic, nonlinear changes in habitat characteristics. On the other hand, very little faunal recovery was seen even in relatively old teak plantation. In general, tree monocultures are unlikely to support recovery of natural forest communities and the combined effect of shortened jhum cultivation cycles and plantation forestry could result in landscapes without mature forest. Lack of source pools of genetic diversity will then lead to altered vegetation succession and faunal community reassembly. It is therefore important that the value of habitat mosaics containing even patches of primary forest and successional secondary habitats be taken into account.

Adaptation, Physiological↗

PubMed2006

Modeling taxa-abundance distributions in microbial communities using environmental sequence data.

We show that inferring the taxa-abundance distribution of a microbial community from small environmental samples alone is difficult. The difficulty stems from the disparity in scale between the number of genetic sequences that can be characterized and the number of individuals in communities that microbial ecologists aspire to describe. One solution is to calibrate and validate a mathematical model of microbial community assembly using the small samples and use the model to extrapolate to the taxa-abundance distribution for the population that is deemed to constitute a community. We demonstrate this approach by using a simple neutral community assembly model in which random immigrations, births, and deaths determine the relative abundance of taxa in a community. In doing so, we further develop a neutral theory to produce a taxa-abundance distribution for large communities that are typical of microbial communities. In addition, we highlight that the sampling uncertainties conspire to make the immigration rate calibrated on the basis of small samples very much higher than the true immigration rate. This scale dependence of model parameters is not unique to neutral theories; it is a generic problem in ecology that is particularly acute in microbial ecology. We argue that to overcome this, so that microbial ecologists can characterize large microbial communities from small samples, mathematical models that encapsulate sampling effects are required.

Biodiversity↗

PubMed2005

A rationally assembled microbial community for growing Tagetes patula L. in a lunar greenhouse.

Well-defined plant-associated bacteria were used for growing French marigolds (Tagetes patula L.) in anorthosite, a substrate of low bioavailability, analogous to a lunar rock. The consortium was composed mainly of plant growth-promoting rhizobacteria and biocontrol agents that were used for seed inoculation. Simultaneously, the sterile substrate was inoculated with the siliceous bacterium Paenibacillus sp. IMBG156. The plant benefited from bacterial activity which resulted in stimulation of seed germination, better plant development, and finally in flowering of inoculated tagetes. In contrast, control plants grew poorly in sterile anorthosite and never flowered. Analysis of bacterial community composition showed that both species colonized plant roots, and there were no shifts in the consortium structure in the rhizosphere of French marigolds within 6 weeks. Paenibacillus sp. IMBG156 was able to release some elements (Ca, Fe, Si) from substrate anorthosite. It was assumed that a rationally assembled consortium of bacterial strains supported growth and development of the model plant under growth-limiting conditions, at least by means of bioleaching and delivering of essential nutritional elements to the plants, and by promoting plant growth.

Bacillaceae↗

PubMed2001

Consistent patterns and the idiosyncratic effects of biodiversity in marine ecosystems.

Revealing the consequences of species extinctions for ecosystem function has been a chief research goal and has been accompanied by enthusiastic debate. Studies carried out predominantly in terrestrial grassland and soil ecosystems have demonstrated that as the number of species in assembled communities increases, so too do certain ecosystem processes, such as productivity, whereas others such as decomposition can remain unaffected. Diversity can influence aspects of ecosystem function, but questions remain as to how generic the patterns observed are, and whether they are the product of diversity, as such, or of the functional roles and traits that characterize species in ecological systems. Here we demonstrate variable diversity effects for species representative of marine coastal systems at both global and regional scales. We provide evidence for an increase in complementary resource use as diversity increases and show strong evidence for diversity effects in naturally assembled communities at a regional scale. The variability among individual species responses is consistent with a positive but idiosyncratic pattern of ecosystem function with increased diversity.

Animals↗

PubMed2026

Microbial succession and assembly shaped by sulfur, spatial partitioning, and water flow in a volcanic acidic river of northern Patagonia.

Extreme acidic environments represent natural laboratories for investigating the mechanisms of microbial community assembly, yet the ecological processes structuring these communities remain incompletely understood. Here, we investigate how spatial partitioning, hydrodynamics, and colonization history shape microbial succession in a unique sulfur-rich, acidic river of volcanic origin in northern Patagonia. We combined 16S rRNA gene profiling and shotgun metagenomics with a multi-scale experimental framework encompassing water column fractionation and colonization assays under native and controlled conditions. Microbial diversity was strongly influenced by spatial fractionation, with free-living communities exhibiting higher richness and temporal variability than particle-associated assemblages. Water flow modulated community structure, increasing evenness in free-living fractions under high-flow conditions, but had limited impact on particle-attached communities. Colonization of sulfur-beads followed a structured successional trajectory, with autotrophic sulfur oxidizers dominating early stages and heterotrophs adapted to biofilm lifestyles increasing over time. Ex situ recolonization assays revealed strong priority effects, with initial colonizers determining successional trajectories. Turnover analyses revealed that the balance among stochastic and deterministic assembly processes shifted across communities with pronounced stochasticity in the water column and flow-dependent effects in free-living communities, while biofilm associated communities on sulfur-beads exhibited stronger contribution of deterministic selection. These ecological patterns were mirrored by functional differentiation, with gene enrichment analyses revealing adaptive signatures of substrate attachment and resource acquisition. By integrating fine-scale environmental variation with colonization dynamics, this study reveals how microscale habitat structure and temporal fluxes jointly modulate microbial community assembly rules, offering a nuanced framework to dissect ecological processes in extreme systems.

Sulfur↗

PubMed2005

Source pool geometry and the assembly of continental avifaunas.

Classical niche-assembly models propose that the composition of biotic communities in continental landscapes is determined chiefly by the autecology of species, interspecific competition, and the diversity of resources and habitats within a region. In contrast, stochastic models propose that simulation algorithms can replicate the macroecological patterns, if not the mechanisms, of community assembly. Despite fundamental differences in assumptions, both categories of models assume that species are drawn from regional source pools. We explored the implications of source pool geometry on the assembly of avian communities with an analysis of assemblage dispersion fields, which can be visualized by overlaying the geographic ranges of all species that occur in an assemblage. Contours of species richness surrounding focal quadrats illustrate the decay rate of assemblage similarity with distance and the probable geometry of assemblage source pools. We used a geographic database for 2,891 species of South American birds to characterize dispersion fields for assemblages sampled by 1 degrees latitude-longitude quadrats (n = 1,676). We show that the median range size of dispersion fields varies by an order of magnitude across the continent. Because abundance generally correlates with geographic range size within taxonomic groups, the number of individuals per species in avifaunal source pools must also vary by an order of magnitude. Most significantly, dispersion field geometry was surprisingly asymmetrical and exhibited complex geographical patterns that were associated with the distribution of biomes. These results are broadly consistent with the predictions of niche-assembly models but offer little support for stochastic assembly models.

Animals↗

PubMed2006

UniFrac--an online tool for comparing microbial community diversity in a phylogenetic context.

BACKGROUND: Moving beyond pairwise significance tests to compare many microbial communities simultaneously is critical for understanding large-scale trends in microbial ecology and community assembly. Techniques that allow microbial communities to be compared in a phylogenetic context are rapidly gaining acceptance, but the widespread application of these techniques has been hindered by the difficulty of performing the analyses. RESULTS: We introduce UniFrac, a web application available at http://bmf.colorado.edu/unifrac, that allows several phylogenetic tests for differences among communities to be easily applied and interpreted. We demonstrate the use of UniFrac to cluster multiple environments, and to test which environments are significantly different. We show that analysis of previously published sequences from the Columbia river, its estuary, and the adjacent coastal ocean using the UniFrac interface provided insights that were not apparent from the initial data analysis, which used other commonly employed techniques to compare the communities. CONCLUSION: UniFrac provides easy access to powerful multivariate techniques for comparing microbial communities in a phylogenetic context. We thus expect that it will provide a completely new picture of many microbial interactions and processes in both environmental and medical contexts.

Bacteria↗

PubMed2006

Evolutionary responses of native plants to novel community members.

Both ecological and evolutionary processes can influence community assembly and stability, and native community members may respond both ecologically and evolutionarily as additional species enter established communities. Biological invasions provide a unique opportunity to examine these responses of native community members to novel species additions. Here, I use reciprocal transplant experiments among naturally invaded and uninvaded environments, along with experimental removals of exotic species, to determine whether exotic plant competitors and exotic insect herbivores evoke evolutionary changes in native plants. Specifically, I address whether the common native plant species Lotus wrangelianus has responded evolutionarily to a series of biological invasions by adapting to the presence of the exotic plant Medicago polymorpha and the exotic insect herbivore Hypera brunneipennis. Despite differences in selection regimes between invaded and uninvaded environments and the presence of genetic variation for traits relevant to the novel competitive and plant-herbivore interactions, these experiments failed to reveal evidence that Lotus has responded evolutionarily to the double invasion of Medicago followed by H. brunneipennis. However, when herbivory from H. brunneipennis was experimentally reduced, Lotus plants from source populations invaded by Medicago outperformed plants from uninvaded source populations when transplanted into heavily invaded destination environments. Therefore, Lotus showed evidence of adaptation to Medicago invasion but not to the newer invasion of an exotic shared herbivore. The presence of this exotic insect herbivore alters the outcome of evolutionary responses in this system and counteracts adaptation by the native Lotus to invasion by the exotic plant Medicago. This result has broad implications for the conservation of native communities. While native species may be able to adapt to the presence of one or a few exotics, a multitude of invasions may limit the ability of natives to respond evolutionarily to the novel and frequently changing selection pressures that arise with subsequent invasions.

Adaptation, Physiological↗

PubMed2001

Species coexistence in temperate, mixed deciduous forests.

The response of tree life-history traits to community profiles (horizontal and vertical heterogeneity, disturbances and biotic interactions) determines community assembly rules, which are currently a hot issue in community ecology. Important mechanisms of coexistence differ throughout the developing stages of tree life history. Many processes of niche partitioning and tradeoffs that potentially enable tree coexistence have been reported to be present in temperate forests, although some of these life-history traits are either correlated with each other or are not independent. Not all of the proposed mechanisms explain coexistence equally well; some could predominate in determining the community organization of forest communities. Population studies need to concentrate more on the component species of a target community to detect the ecological assembly rule. These approaches can also address how chance factors contribute to the composition of temperate tree communities, which might be less dependent on chance than are tropical ones.

Journal Article↗

PubMed2006

Predicting understorey structure from the presence and composition of canopies: an assembly rule for marine algae.

Assembly rules provide a useful framework for predicting patterns of community assembly under defined environmental conditions. Habitat created by canopy-forming algae (such as kelps) provides a promising system for identifying assembly rules because canopies typically have a large and predictable influence on understorey communities. Across >1,000 km of subtidal South Australian coastline, we identified natural associations between assemblages of understorey algae and (1) monospecific canopies of Ecklonia radiata, (2) canopies comprised of E. radiata mixed with Fucales (Cystophora spp. and Sargassum spp.), and (3) gaps among canopies of algae. We were able to recreate these associations with experimental tests that quantified the assembly of understorey algae among these three habitat types. We propose the assembly rule that understorey communities on subtidal rocky coast in South Australia will be (1) monopolised by encrusting coralline algae beneath monospecific canopies of E. radiata, (2) comprised of encrusting corallines, encrusting non-corallines, and sparse covers of articulated corallines, beneath mixed E. radiata-Fucales canopies, and (3) comprised of extensive covers of articulated corallines and filamentous turfs, as well as sparse covers of foliose algae and juvenile canopy-formers, within gaps. Consistencies between natural patterns and experimental effects demonstrate how algal canopies can act as a filter to limit the subsets of species from the locally available pool that are able to assemble beneath them. Moreover, the subsets of species that assemble to subtidal rocky substrata in South Australia appear to be predictable, given knowledge of the presence and composition of canopies incorporating E. radiata.

Analysis of Variance↗

PubMed2006

From plant traits to plant communities: a statistical mechanistic approach to biodiversity.

We developed a quantitative method, analogous to those used in statistical mechanics, to predict how biodiversity will vary across environments, which plant species from a species pool will be found in which relative abundances in a given environment, and which plant traits determine community assembly. This provides a scaling from plant traits to ecological communities while bypassing the complications of population dynamics. Our method treats community development as a sorting process involving species that are ecologically equivalent except with respect to particular functional traits, which leads to a constrained random assembly of species; the relative abundance of each species adheres to a general exponential distribution as a function of its traits. Using data for eight functional traits of 30 herbaceous species and community-aggregated values of these traits in 12 sites along a 42-year chronosequence of secondary succession, we predicted 94% of the variance in the relative abundances.

Biodiversity↗

PubMed2006

A trait-based test for habitat filtering: convex hull volume.

Community assembly theory suggests that two processes affect the distribution of trait values within communities: competition and habitat filtering. Within a local community, competition leads to ecological differentiation of coexisting species, while habitat filtering reduces the spread of trait values, reflecting shared ecological tolerances. Many statistical tests for the effects of competition exist in the literature, but measures of habitat filtering are less well-developed. Here, we present convex hull volume, a construct from computational geometry, which provides an n-dimensional measure of the volume of trait space occupied by species in a community. Combined with ecological null models, this measure offers a useful test for habitat filtering. We use convex hull volume and a null model to analyze California woody-plant trait and community data. Our results show that observed plant communities occupy less trait space than expected from random assembly, a result consistent with habitat filtering.

Ecosystem↗

PubMed2005

Phylogenetic analysis of ecomorphological divergence, community structure, and diversification rates in dusky salamanders (Plethodontidae: Desmognathus).

An important dimension of adaptive radiation is the degree to which diversification rates fluctuate or remain constant through time. Focusing on plethodontid salamanders of the genus Desmognathus, we present a novel synthetic analysis of phylogeographic history, rates of ecomorphological evolution and species accumulation, and community assembly in an adaptive radiation. Dusky salamanders are highly variable in life history, body size, and ecology, with many endemic lineages in the southern Appalachian Highlands of eastern North America. Our results show that life-history evolution had important consequences for the buildup of plethodontid-salamander species richness and phenotypic disparity in eastern North America, a global hot spot of salamander biodiversity. The origin of Desmognathus species with aquatic larvae was followed by a high rate of lineage accumulation, which then gradually decreased toward the present time. The peak period of lineage accumulation in the group coincides with evolutionary partitioning of lineages with aquatic larvae into seepage, stream-edge, and stream microhabitats. Phylogenetic simulations demonstrate a strong correlation between morphology and microhabitat ecology independent of phylogenetic effects and suggest that ecomorphological changes are concentrated early in the radiation of Desmognathus. Deep phylogeographic fragmentation within many codistributed ecomorph clades suggests long-term persistence of ecomorphological features and stability of endemic lineages and communities through multiple climatic cycles. Phylogenetic analyses of community structure show that ecomorphological divergence promotes the coexistence of lineages and that repeated, independent evolution of microhabitat-associated ecomorphs has a limited role in the evolutionary assembly of Desmognathus communities. Comparing and contrasting our results to other adaptive radiations having different biogeographic histories, our results suggest that rates of diversification during adaptive radiation are intimately linked to the degree to which community structure persists over evolutionary time.

Adaptation, Biological↗

PubMed2005

Proteogenomic approaches for the molecular characterization of natural microbial communities.

At the present time we know little about how microbial communities function in their natural habitats. For example, how do microorganisms interact with each other and their physical and chemical surroundings and respond to environmental perturbations? We might begin to answer these questions if we could monitor the ways in which metabolic roles are partitioned amongst members as microbial communities assemble, determine how resources such as carbon, nitrogen, and energy are allocated into metabolic pathways, and understand the mechanisms by which organisms and communities respond to changes in their surroundings. Because many organisms cannot be cultivated, and given that the metabolisms of those growing in monoculture are likely to differ from those of organisms growing as part of consortia, it is vital to develop methods to study microbial communities in situ. Chemoautotrophic biofilms growing in mine tunnels hundreds of meters underground drive pyrite (FeS(2)) dissolution and acid and metal release, creating habitats that select for a small number of organism types. The geochemical and microbial simplicity of these systems, the significant biomass, and clearly defined biological-inorganic feedbacks make these ecosystem microcosms ideal for development of methods for the study of uncultivated microbial consortia. Our approach begins with the acquisition of genomic data from biofilms that are sampled over time and in different growth conditions. We have demonstrated that it is possible to assemble shotgun sequence data to reveal the gene complement of the dominant community members and to use these data to confidently identify a significant fraction of proteins from the dominant organisms by mass spectrometry (MS)-based proteomics. However, there are technical obstacles currently restricting this type of "proteogenomic" analysis. Composite genomic sequences assembled from environmental data from natural microbial communities do not capture the full range of genetic potential of the associated populations. Thus, it is necessary to develop bioinformatics approaches to generate relatively comprehensive gene inventories for each organism type. These inventories are critical for expression and functional analyses. In proteomic studies, for example, peptides that differ from those predicted from gene sequences can be measured, but they generally cannot be identified by database matching, even if the difference is only a single amino acid residue. Furthermore, many of the identified proteins have no known function. We propose that these challenges can be addressed by development of proteogenomic, biochemical, and geochemical methods that will be initially deployed in a simple, natural model ecosystem. The resulting approach should be broadly applicable and will enhance the utility and significance of genomic data from isolates and consortia for study of organisms in many habitats. Solutions draining pyrite-rich deposits are referred to as acid mine drainage (AMD). AMD is a very prevalent, international environmental problem associated with energy and metal resources. The biological-mineralogical interactions that define these systems can be harnessed for energy-efficient metal recovery and removal of sulfur from coal. The detailed understanding of microbial ecology and ecosystem dynamics resulting from the proposed work will provide a scientific foundation for dealing with the environmental challenges and technological opportunities, and yield new methods for analysis of more complex natural communities.

Ecosystem↗