Sphagnum auriculatum Schimp. in Portugal with late Quaternary occurrences

Sphagnum auriculatum Schimp. occurs in Portugal mainly in the northem and central parts of the country where the precipitation rates vary between 800-2800 mm/yr. It occupies the atlantic and pre-atlantic temtories though two of the collections were made south of Lisbon, in the mediterranean tenitory. Holocene records exist 50 km south of these locations suggesting a wider distribution of this species towards the south in the Quaternary. Climate changes together with habitat disturbances may be responsable for its disappearance from these areas.S. auriculatum Schimp es troba a Portugal, principalment, al nord i centre del país, on hi ha una precipitació anual de 800 a 2800 mm. Ocupa els territoris atlàntics i subatlàntics tret de dues localitats al sud de Lisboa, de tipus mediterrani. S'han trobat registres holocènics a 50 km al sud d'aquestes localitats i això fa pensar que aquesta espècie presentava, al Quaternari, una àrea de distribució més àmplia. Canvis climàtics juntament amb alteracions del medi poden ser la causa de la desaparició de l'espècie en aquestes àrees

Analyses of Charophyte Chloroplast Genomes Help Characterize the Ancestral Chloroplast Genome of Land Plants

The file attached is the published version of the article. Revised LorP 22/5/2017©The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Composition and activity of nitrifier communities in soil are unresponsive to elevated temperature and CO2, but strongly affected by drought

Nitrification is a fundamental process in terrestrial nitrogen cycling. However, detailed information on how climate change affects the structure of nitrifier communities is lacking, specifically from experiments in which multiple climate change factors are manipulated simultaneously. Consequently, our ability to predict how soil nitrogen (N) cycling will change in a future climate is limited. We conducted a field experiment in a managed grassland and simultaneously tested the effects of elevated atmospheric CO2, temperature, and drought on the abundance of active ammonia-oxidizing bacteria (AOB) and archaea (AOA), comammox (CMX) Nitrospira, and nitrite-oxidizing bacteria (NOB), and on gross mineralization and nitrification rates. We found that N transformation processes, as well as gene and transcript abundances, and nitrifier community composition were remarkably resistant to individual and interactive effects of elevated CO2 and temperature. During drought however, process rates were increased or at least maintained. At the same time, the abundance of active AOB increased probably due to higher NH4+ availability. Both, AOA and comammox Nitrospira decreased in response to drought and the active community composition of AOA and NOB was also significantly affected. In summary, our findings suggest that warming and elevated CO2 have only minor effects on nitrifier communities and soil biogeochemical variables in managed grasslands, whereas drought favors AOB and increases nitrification rates. This highlights the overriding importance of drought as a global change driver impacting on soil microbial community structure and its consequences for N cycling

De Ira ad novatum

Marca tip. na portT. III. XXIII , 186 pContén Libro II

Sphagnum auriculatum Schimp. in Portugal with late Quaternary occurrences

Sphagnum auriculatum Schimp. occurs in Portugal mainly in the northem and central parts of the country where the precipitation rates vary between 800-2800 mm/yr. It occupies the atlantic and pre-atlantic temtories though two of the collections were made south of Lisbon, in the mediterranean tenitory. Holocene records exist 50 km south of these locations suggesting a wider distribution of this species towards the south in the Quaternary. Climate changes together with habitat disturbances may be responsable for its disappearance from these areas.S. auriculatum Schimp es troba a Portugal, principalment, al nord i centre del país, on hi ha una precipitació anual de 800 a 2800 mm. Ocupa els territoris atlàntics i subatlàntics tret de dues localitats al sud de Lisboa, de tipus mediterrani. S'han trobat registres holocènics a 50 km al sud d'aquestes localitats i això fa pensar que aquesta espècie presentava, al Quaternari, una àrea de distribució més àmplia. Canvis climàtics juntament amb alteracions del medi poden ser la causa de la desaparició de l'espècie en aquestes àrees

Down-regulation of the bacterial protein biosynthesis machinery in response to weeks, years, and decades of soil warming

How soil microorganisms respond to global warming is key to infer future soil-climate feedbacks, yet poorly understood. Here, we applied metatranscriptomics to investigate microbial physiological responses to mediumterm (8 years) and long-term (>50 years) subarctic grassland soil warming of +6°C. Besides indications for a community-wide up-regulation of centralmetabolic pathways and cell replication, we observed a down-regulation of the bacterial protein biosynthesis machinery in the warmed soils, coinciding with a lower microbial biomass, RNA, and soil substrate content. We conclude that permanently accelerated reaction rates at higher temperatures and reduced substrate concentrations result in cellular reduction of ribosomes, the macromolecular complexes carrying out protein biosynthesis. Later efforts to test this, including a short-term warming experiment (6 weeks, +6°C), further supported our conclusion. Down-regulating the protein biosynthesis machinery liberates energy and matter, allowing soil bacteria to maintain high metabolic activities and cell division rates even after decades of warming

New national and regional bryophyte records, 19

[No abstract available