The global distribution of soil animals and the relationship of below-ground biodiversity to above-ground biodiversity are not well understood. We examined 17,516 environmental 18S rRNA gene sequences representing 20 phyla of soil animals sampled from 11 locations covering a range of biomes and latitudes around the world. No globally cosmopolitan taxa were found and only 14 of 2,259 operational taxonomic units (OTUs) found were common to four or more locations. Half of those were circumpolar and may reflect higher connectivity among circumpolar locations compared with other locations in the study. Even when OTU assembly criteria were relaxed to approximate the family taxonomic level, only 34 OTUs were common to four or more locations. A comparison of our diversity and community structure data to environmental factors suggests that below-ground animal diversity may be inversely related to above-ground biodiversity. Our data suggest that greater soil inorganic N and lower pH could explain the low below-ground biodiversity found at locations of high above-ground biodiversity. Our locations could also be characterized as being dominated by microarthropods or dominated by nematodes. Locations dominated by arthropods were primarily forests with lower soil pH, root biomass, mean annual temperature, low soil inorganic N and higher C:N, litter and moisture compared with nematode-dominated locations, which were mostly grasslands. Overall, our data indicate that small soil animals have distinct biogeographical distributions and provide unique evidence of the link between above-ground and belowground biodiversity at a global scale.cosmopolitan species | endemism

Aim To conduct the first global‐scale investigation of soil nematode assemblages using a standardized approach to quantify how environmental and climatic variables influence family assemblage structure in nematodes and determine whether nematode families have restricted distributions. Location Global. Methods We collected soil nematodes within four 10 m × 10 m plots distributed evenly along a 900‐m transect at each of 12 sites representing multiple ecosystem types across a latitudinal gradient (68° N to 77° S) on six continents. We assigned > 28,000 individuals to family level and trophic group morphologically. Results We recorded a total of 43 nematode families, but sites varied considerably in family richness (1–30). Families differed in their ranges with 12 families occurring at 10 or more sites, while 14 families occurred at three or fewer sites. Total nematode and trophic group abundances were generally related to soil characteristics, including bulk density and soil moisture, but we found no good predictor of family richness, diversity or evenness at the plot level. Family richness, diversity and evenness were considerably lower in the high‐latitude polar desert than elsewhere, but only family diversity showed a significant, albeit weak, latitudinal gradient. Nematode assemblage composition was quite strongly related to climate: 65% and 58% of the variation in assemblage composition across sites could be accounted for by mean annual rainfall and temperature, respectively. Main conclusions Nematode families display macroecological patterns similar to other organisms, such as a positive abundance–range size relationship and restricted distribution of some families. Local nematode abundances were related to soil characteristics, but we found no relationships between family richness and environmental or climatic variables. Family composition was related to mean annual rainfall and temperature, suggesting that climate is a good predictor of local assemblage structure. As a result, climate change may have a significant impact on nematode assemblages, with potential implications for ecosystem functioning.

Dual-functional antifogging/antimicrobial polymer coatings were prepared by forming a semi-interpenetrating polymer network (SIPN) of partially quaternized poly(2-(dimethylamino)ethyl methacrylate-co-methyl methacrylate) and polymerized ethylene glycol dimethacrylate network. The excellent antifogging behavior of the smooth coating was mainly attributed to the hydrophilic/hydrophobic balance of the partially quaternized copolymer, while the covalently bonded, hydrophobic quaternary ammonium compound (5 mol % in the copolymer) rendered the coating strongly antimicrobial, as demonstrated by the total kill against both Gram-positive Staphylococcus epidermidis and Gram-negative Escherichia coli. The antimicrobial action of the SIPN coating was based on contact killing, without leaching of bactericidal species, as revealed by a zone-of-inhibition test. This type of dual-functional coating may find unique applications where both antimicrobial and antifogging properties are desired.

We designed and synthesized a novel quaternary ammonium methacrylate compound (QAC-2) bearing a perfluoroalkyl tail on one end and an acrylic moiety on the other. Via one-step UV curing of QAC-2 and methyl methacrylate (MMA) with ethylene glycol dimethacrylate (EGDMA) as the cross-linker, we obtained cross-linked coatings with excellent antimicrobial property, as demonstrated by the total kill against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus epidermidis (S. epidermidis) at a QAC-2 concentration as low as ∼0.06 mol % (∼0.4 wt %) relative to MMA, which was substantially lower than the QAC amount needed in the coatings containing QACs with a hydrocarbon tail. A zone of inhibition test confirmed that the antimicrobial effect was on the basis of contact killing and there was no leaching of antimicrobial species from the cross-linked coating. The high antimicrobial potency in QAC-2-containing films was the consequence of strong surface enrichment of the fluorinated QAC, as confirmed by X-ray photoelectron spectroscopy (XPS).

Summary• Ectomycorrhizas may interact with saprotrophic microorganisms to influence decomposition. These interactions are poorly understood.• We buried mesh envelopes filled with either litter or F-layer material in the forest floor of a Pinus resinosa plantation. After 16 months we characterized decomposition, C : N ratio, water content, and the density of four ectomycorrhiza morphotypes.• For both substrates there were negative correlations between ectomycorrhiza density and decomposition, and between ectomycorrhiza density and water content. The relative proportion of morphotypes was significantly different in litter and F-layer material buried at the same depth in the forest floor.• We conclude that the negative effect of ectomycorrhizas on decomposition could be mediated by extraction of water, particularly in relatively dry years. The 'Gadgil effect' may be explained by this phenomenon. In wetter years, water extraction may be less consequential. Also, variation in substrate quality may influence the structure of ectomycorrhizal fungal communities.