Pyrene infected soil removal employing microwavemagnetite initialized persulfate oxidation

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We predict that in well-mixed environments, traits will be selected exclusively for their direct fitness effects, while in spatially structured environments, traits may also be selected for their indirect fitness effects. Selection of indirectly beneficial traits should result in an increase in interaction strength over time, while selection of directly beneficial traits should not have such a systematic effect. We tested our intuitions using a simple quantitative model and found support for our hypotheses. The next step will be to test these hypotheses experimentally and provide input for a more refined version of the model in turn, thus closing the scientific cycle of models and experiments. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.Surface-attached microbial communities consist of different cell types that, at least to some degree, organize themselves non-randomly across space (referred to as spatial self-organization). While spatial self-organization can have important effects on the functioning, ecology and evolution of communities, the underlying determinants of spatial self-organization remain unclear. Here, we hypothesize that the presence of physical objects across a surface can have important effects on spatial self-organization. Using pairs of isogenic strains of Pseudomonas stutzeri, we performed range expansion experiments in the absence or presence of physical objects and quantified the effects on spatial self-organization. We demonstrate that physical objects create local deformities along the expansion frontier, and these deformities increase in magnitude during range expansion. The deformities affect the densities of interspecific boundaries and diversity along the expansion frontier, and thus affect spatial self-organization, but the effects are interaction-dependent. For competitive interactions that promote sectorized patterns of spatial self-organization, physical objects increase the density of interspecific boundaries and diversity. DX3213B By contrast, for cross-feeding interactions that promote dendritic patterns, they decrease the density of interspecific boundaries and diversity. These qualitatively different outcomes are probably caused by fundamental differences in the orientations of the interspecific boundaries. Thus, in order to predict the effects of physical objects on spatial self-organization, information is needed regarding the interactions present within a community and the general geometric shapes of spatial self-organization that emerge from those interactions. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.Much of Earth's biodiversity has the capacity to engage in dormancy, a reversible state of reduced metabolic activity. By increasing resilience to unfavourable conditions, dormancy leads to the accumulation of 'seed banks'. These reservoirs of genetic and phenotypic diversity should diminish the strength of environmental filtering and increase rates of dispersal. Although prevalent among single-celled organisms, evidence that dormancy influences patterns of microbial biogeography is lacking. We constructed geographical and environmental distance-decay relationships (DDRs) for the total (DNA) and active (RNA) portions of bacterial communities in a regional-scale 16S rRNA survey of forested ponds in Indiana, USA. As predicted, total communities harboured greater diversity and exhibited weaker DDRs than active communities. These observations were robust to random resampling and different community metrics. To evaluate the processes underlying the biogeographic patterns, we developed a platform of mechanistic models that used the geographical coordinates and environmental characteristics of our study system. Based on more than 106 simulations, our models approximated the empirical DDRs when there was strong environmental filtering along with the presence of long-lived seed banks. By contrast, the inclusion of dispersal generally decreased model performance. Together, our findings support recent theoretical predictions that seed banks can influence the biogeographic patterns of microbial communities. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.Linking 'omics measurements with biogeochemical cycles is a widespread challenge in microbial community ecology. Here, we propose applying genomic adaptation as 'biosensors' for microbial investments to overcome nutrient stress. We then integrate this genomic information with a trait-based model to predict regional shifts in the elemental composition of marine plankton communities. We evaluated this approach using metagenomic and particulate organic matter samples from the Atlantic, Indian and Pacific Oceans. We find that our genome-based trait model significantly improves our prediction of particulate C P (carbon phosphorus) across ocean regions. Furthermore, we detect previously unrecognized ocean areas of iron, nitrogen and phosphorus stress. In many ecosystems, it can be very challenging to quantify microbial stress. Thus, a carefully calibrated genomic approach could become a widespread tool for understanding microbial responses to environmental changes and the biogeochemical outcomes. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.Microbial physiological processes are intimately involved in nutrient cycling. However, it remains unclear to what extent microbial diversity or community composition is important for determining the rates of ecosystem-scale functions. There are many examples of positive correlations between microbial diversity and ecosystem function, but how microbial communities 'map' onto ecosystem functions remain unresolved. This uncertainty limits our ability to predict and manage crucial microbially mediated processes such as nutrient losses and greenhouse gas emissions. To overcome this challenge, we propose integrating traditional biodiversity-ecosystem function research with ideas from genotype-phenotype mapping in organisms. We identify two insights from genotype-phenotype mapping that could be useful for microbial biodiversity-ecosystem function studies the concept of searching 'agnostically' for markers of ecosystem function and controlling for population stratification to identify microorganisms uniquely associated with ecosystem function.