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Despite glyphosate's wide use for weed control in agriculture, questions remain about the herbicide's effect on soil microbial communities. The existing scientific literature contains conflicting results, from no observable effect of glyphosate to the enrichment of agricultural pathogens such as Fusarium spp. We conducted a comprehensive field-based study to compare the microbial communities on the roots of plants that received a foliar application of glyphosate to adjacent plants that did not. The 2-year study was conducted in Beltsville, MD, and Stoneville, MS, with corn and soybean crops grown in a variety of organic and conventional farming systems. By sequencing environmental metabarcode amplicons, the prokaryotic and fungal communities were described, along with chemical and physical properties of the soil. Sections of corn and soybean roots were plated to screen for the presence of plant pathogens. Geography, farming system, and season were significant factors determining the composition of fungal and prokaryotic communities. Plots treated with glyphosate did not differ from untreated plots in overall microbial community composition after controlling for other factors. We did not detect an effect of glyphosate treatment on the relative abundance of organisms such as Fusarium spp. [ABSTRACT FROM AUTHOR]

Urbanization results in the systemic conversion of land-use, driving habitat and biodiversity loss. The "urban convergence hypothesis" posits that urbanization represents a merging of habitat characteristics, in turn driving physiological and functional responses within the biotic community. To test this hypothesis, we sampled five cities (Baltimore, MD, United States; Helsinki and Lahti, Finland; Budapest, Hungary; Potchefstroom, South Africa) across four different biomes. Within each city, we sampled four land-use categories that represented a gradient of increasing disturbance and management (from least intervention to highest disturbance: reference, remnant, turf/lawn, and ruderal). Previously, we used amplicon sequencing that targeted bacteria/archaea (16S rRNA) and fungi (ITS) and reported convergence in the archaeal community. Here, we applied shotgun metagenomic sequencing and QPCR of functional genes to the same soil DNA extracts to test convergence in microbial function. Our results suggest that urban land-use drives changes in gene abundance related to both the soil N and C metabolism. Our updated analysis found taxonomic convergence in both the archaeal and bacterial community (16S amplicon data). Convergence of the archaea was driven by increased abundance of ammonia oxidizing archaea and genes for ammonia oxidation (QPCR and shotgun metagenomics). The proliferation of ammonia-oxidizers under turf and ruderal land-use likely also contributes to the previously documented convergence of soil mineral N pools. We also found a higher relative abundance of methanogens (amplicon sequencing), a higher relative abundance of gene sequences putatively identified as Ni-Fe hydrogenase and nickel uptake (shotgun metagenomics) under urban land-use; and a convergence of gene sequences putatively identified as contributing to the nickel transport function under urban turf sites. High levels of disturbance lead to a higher relative abundance of gene sequences putatively identified as multiple antibiotic resistance protein marA and multidrug efflux pump mexD, but did not lead to an overall convergence in antibiotic resistance gene sequences. [ABSTRACT FROM AUTHOR]

Agriculture, by its intentional design, manipulates the ecological functions of soils. It does so by altering carbon and nutrient inputs; by controlling the plant community; and in the case of tillage, by physically disrupting and redistributing the soil within the soil profile. While there are many studies that contrast soil microbiomes across farming systems, few studies have examined the effect of farming system on the vertical organization of taxa in the soil profile. We hypothesized that large effects of farming systems on edaphic factors would lead to large impacts on the microbial community that would reflect the underlying life history strategy of the microbes. For example, that tillage would increase the proportion of unicellular fungi. Our study compared farming systems that had been in place for 13 years in the mid-Atlantic region of the United States. Each system is a 3-year rotation of corn (Zea mays), soybean (Glycine max), and wheat (Triticum aestivum), managed with either conventional no-till, conventional chisel-till, or using organic methods. We determined the relative effect of long-term farming system management on edaphic factors and the soil microbial community with depth structured sampling (0–5, 5–10, 10-Ap, Ap-30 cm). We found relatively small effects of farming system but substantial effects of depth on edaphic factors and microbial communities. For example, differences in management resulted in subtle differences in %C above the Ap horizon. Fungal gene abundance increased in the organic system relative to the no-till system, although neither fungal nor bacterial richness differed across farming systems. Farming system effects on microbial community composition were greatest in the top 10 cm but did not affect the abundance of unicellular fungi. Several groups including Pseudomonas and Mortierellomycota appear to be sensitive to redistribution by tillage in the organic system, but it is not clear to what extent this effect is due to legacy DNA from tillage. Thirteen-year management of organic and conventional grain farming systems results in modest differences to microbial communities along soil depth profiles 1) Organic treatment results in a increase in soil %C and differences in %C depth distribution 2) No difference in richness and evenness among farming systems 3) A 30 cm depth profile represents a much greater environmental gradient for microbial abundance and diversity than differences among long-term row-crop farming systems that differ in tillage, fertility and pest management [Display omitted] • Depth had larger effect than farming system on microbial community. • Farming system effects were concentrated in top 10 cm. • Farming systems altered the distribution of some taxa across depth increments. • No effect of farming system on abundance of unicellular fungi. [ABSTRACT FROM AUTHOR]

The article reviews the architectural design of the Bloch-Tank House in Stuttgart, Germany, designed by Oscar Bloch and Ernst Guggenheimer.

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In urban landscapes, humans are the most significant factor determining belowground diversity, including earthworms. Within the framework of the Global Urban Soil Ecology and Education Network (GLUSEEN), a multi-city comparison was carried out to assess the effects of soil disturbance on earthworms. In each of five cities (Baltimore, USA; Budapest, Hungary; Helsinki and Lahti, Finland; Potchefstroom, South Africa), covering four climatic and biogeographical regions, four habitat types (ruderal, turf/lawn, remnant and reference) were sampled. The survey resulted in 19 species belonging to 9 genera and 4 families. The highest total species richness was recorded in Baltimore (16), while Budapest and the Finnish cities had relatively low (5–6) species numbers. Remnant forests and lawns supported the highest earthworm biomass. Soil properties (i.e. pH and organic matter content) explained neither earthworm community composition nor abundance. Evaluating all cities together, earthworm communities were significantly structured by habitat type. Communities in the two adjacent cities, Helsinki and Lahti were very similar, but Budapest clearly separated from the Finnish cities. Earthworm community structure in Baltimore overlapped with that of the other cities. Despite differences in climate, soils and biogeography among the cities, earthworm communities were highly similar within the urban habitat types. This indicates that human-mediated dispersal is an important factor shaping the urban fauna, both at local and regional scales. • Earthworm communities varied within and among urban habitat types. • Remnant forests and urban lawns were the most favorable habitats for earthworms. • Different mechanisms lead to high similarity of urban earthworm assemblages. [ABSTRACT FROM AUTHOR]