Shifts in soil microbial communities over altitudinal gradients and the driving factors are poorly studied. Their elucidation is indispensable to gain a comprehensive understanding of the response of ecosystems to global climate change. Here, we investigated soil archaeal, bacterial, and fungal communities at four Alpine forest sites representing a climosequence, over an altitudinal gradient from 545 to 2000 m above sea level (asl), regarding abundance and diversity by using qPCR and Illumina sequencing, respectively. Archaeal community was dominated by Thaumarchaeota, and no significant shifts were detected in abundance or community composition with altitude. The relative bacterial abundance increased at higher altitudes, which was related to increasing levels of soil organic matter and nutrients with altitude. Shifts in bacterial richness and diversity as well as community structure (comprised basically of Proteobacteria, Acidobacteria, Actinobacteria, and Bacteroidetes) significantly correlated with several environmental and soil chemical factors, especially soil pH. The site at the lowest altitude harbored the highest bacterial richness and diversity, although richness/diversity community properties did not show a monotonic decrease along the gradient. The relative size of fungal community also increased with altitude and its composition comprised Ascomycota, Basidiomycota, and Zygomycota. Changes in fungal richness/diversity and community structure were mainly governed by pH and C/N, respectively. The variation of the predominant bacterial and fungal classes over the altitudinal gradient was the result of the environmental and soil chemical factors prevailing at each site.Electronic supplementary materialThe online version of this article (doi:10.1007/s00248-016-0748-2) contains supplementary material, which is available to authorized users.

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The study of soil microbial responses to environmental changes is useful to improve simulation models and mitigation strategies for climate change. We here investigated two Alpine forest sites (deciduous forest vs. coniferous forest) situated at different altitudes (altitudinal effect) in spring and autumn (seasonal effect) regarding: (i) bacterial and fungal abundances (qPCR); (ii) diversity and structure of bacterial and fungal communities (amplicon sequencing); and (iii) diversity and composition of microbial functional gene community (Geochip 5.0). Significant altitudinal changes were detected in microbial abundances as well as in diversity and composition of taxonomic and functional communities as a consequence of the differences in pH, soil organic matter (SOM) and nutrient contents and soil temperatures measured between both sites. A network analysis revealed that deciduous forest site (at lower altitude) presented a lower resistance to environmental changes than that of coniferous forest site (at higher altitude). Significant seasonal effects were detected only for the diversity (higher values in autumn) and composition of microbial functional gene community, which was related to the non-significant increased SOM and nutrient contents detected in autumn respect to spring and the presumable high capacity of soil microbial communities to respond in functional terms to discreet environmental changes.

Objective-To determine the clinical features and long term prognosis of infective endocarditis in patients who were not drug addicts. Design-Prospective case series. Setting-A university hospital that is both a referral and a primary care centre. Patients-138 consecutive cases of infective endocarditis diagnosed and treated from January 1987 to March 1997. Results-Mean patient age was 44 (20) years old. 95 patients (69%) had native valve endocarditis and 43 (31%) had prosthetic valve endocarditis. Staphylococci were the causal microorganisms in 34% of cases and streptococci in 33%. Severe complications occurred in 83% of patients and 51% of patients underwent surgery during the active phase (22% was emergency surgery). Inpatient mortality was 21%. During a follow up of 56 (44) months, 10 patients (9%) needed late cardiac surgery and seven (5% of the whole series) died. Overall 10 year survival was 71%. There were no significant diVerences in survival depending on the type of treatment received during the hospital stay (medical or combined medical-surgical). Conclusions-A high early surgery rate is related to good long term results and does not increase in-hospital mortality. Medical treatment, however, also oVers favourable long term results in cases of responsive infective endocarditis where poor prognostic factors are absent. (Heart 2000;83:525-530)