A Large Fraction of Soil Microbial Taxa Is Sensitive to Experimental Warming.

Global warming is expected to significantly impact the soil fungal and bacterial microbiomes, yet the predominant ecological response of microbial taxa-whether an increase, decrease, or no change-remains unclear. It is also unknown whether microbial taxa from different evolutionary lineages exhibit common patterns and what factors drive these changes. Here, we analyzed three mid-term (> 5 years) warming experiments across contrasting dryland and temperate-boreal ecosystems, encompassing over 500 topsoil samples collected across multiple time points.

The Society of Information and the European Citizens' Perception of Climate Change: Natural or Anthropological Causes.

The scientific community has reached a consensus on humans' important role as causative agents of climate change; however, branches of society are still sceptical about this. Climate change is a key issue for humanity and only the commitment to change human attitudes and lifestyles, at the global level, can be effective in its mitigation. With this purpose, it is important to convey the right message and prevent misinformation to manipulate people's minds.

Effects of vegetation on soil cyanobacterial communities through time and space.

Photoautotrophic soil cyanobacteria play essential ecological roles and are known to exhibit large changes in their diversity and abundance throughout early succession. However, much less is known about how and why soil cyanobacterial communities change as soil develops over centuries and millennia, and the effects that vegetation have on such communities. We combined an extensive field survey, including 16 global soil chronosequences across contrasting ecosystems (from deserts to tropical forests), with molecular analyses to investigate how the diversity and abundance of photosynthetic and nonphotosynthetic soil cyanobacteria are affected by vegetation change during soil development, over time periods from hundreds to thousands of years.

Global homogenization of the structure and function in the soil microbiome of urban greenspaces.

The structure and function of the soil microbiome of urban greenspaces remain largely undetermined. We conducted a global field survey in urban greenspaces and neighboring natural ecosystems across 56 cities from six continents, and found that urban soils are important hotspots for soil bacterial, protist and functional gene diversity, but support highly homogenized microbial communities worldwide. Urban greenspaces had a greater proportion of fast-growing bacteria, algae, amoebae, and fungal pathogens, but a lower proportion of ectomycorrhizal fungi than natural ecosystems.

Contrasting mechanisms underlie short- and longer-term soil respiration responses to experimental warming in a dryland ecosystem.

Soil carbon losses to the atmosphere through soil respiration are expected to rise with ongoing temperature increases, but available evidence from mesic biomes suggests that such response disappears after a few years of experimental warming. However, there is lack of empirical basis for these temporal dynamics in soil respiration responses, and for the mechanisms underlying them, in drylands, which collectively form the largest biome on Earth and store 32% of the global soil organic carbon pool. We coupled data from a 10 year warming experiment in a biocrust-dominated dryland ecosystem with laboratory incubations to confront 0-2 years (short-term hereafter) versus 8-10 years (longer-term hereafter) soil respiration responses to warming.

Diversity of biocrust-forming cyanobacteria in a semiarid gypsiferous site from Central Spain.

Cyanobacteria are a key constituent of biocrusts, communities dominated by lichens, mosses and associated microorganisms, which are prevalent in drylands worldwide and that largely determine their functioning. Despite their importance, there are large gaps in our knowledge of the composition and diversity of cyanobacteria associated with biocrusts, particularly in areas such as the Mediterranean Basin. We studied the diversity of these cyanobacteria in a gypsiferous grassland from Central Spain using both morphological identification after cultivation and genetic analyses with the 16S rRNA gene.