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Background FIBRONET was an observational, multicentre, prospective cohort study investigating the baseline characteristics, clinical course of disease and use of antifibrotic treatment in Italian patients with idiopathic pulmonary fibrosis (IPF). Methods Patients aged ≥ 40 years diagnosed with IPF within the previous 3 months at 20 Italian centres were consecutively enrolled and followed up for 12 months, with evaluations at 3, 6, 9 and 12 months. The primary objective was to describe the clinical course of IPF over 12 months of follow-up, including changes in lung function measured by % predicted forced vital capacity (FVC% predicted). Results 209 patients (82.3% male, mean age 69.54 ± 7.43 years) were enrolled. Mean FVC% predicted was relatively preserved at baseline (80.01%). The mean time between IPF diagnosis and initiation of antifibrotic therapy was 6.38 weeks; 72.3% of patients received antifibrotic therapy within the first 3 months of follow-up, and 83.9% within 12 months of follow-up. Mean FVC% predicted was 80.0% at baseline and 82.2% at 12 months, and 47.4% of patients remained stable (i.e. had no disease progression) in terms of FVC% predicted during the study. Conclusions FIBRONET is the first prospective, real-life, observational study of patients with IPF in Italy. The short time between diagnosis and initiation of antifibrotic therapy, and the stable lung function between baseline and 12 months, suggest that early diagnosis and prompt initiation of antifibrotic therapy may preserve lung function in patients with IPF. Trial registration: NCT02803580

Reproducibility and reliability of soil enzyme assays need to be validated by comparing results among different labs. The Italian Group of Enzymology organized a ring test among five labs. Beta-glucosidase, acid- and alkaline phosphatase activities were chosen as they are all measurable by using substrates with wide applicability, i.e. p-nitrophenyl derivatives. The five labs preliminarily agreed and standardised the specific methodological procedure for each enzymatic activity, also taking into account factors such as practicability and equipment availability. Nine soils with contrasting physico- chemical and biological properties were adequately sampled, pre-treated and sieved, in order to ensure representativeness and homogeneity. Then they were sent to each laboratory. Results of ring test were evaluated using the Z-score procedure. Systematic error and random error of a specific lab were calculated, respectively, as the average Z-score and standard deviation of Z-score for a given enzyme in that specific lab. Due to large endogeneity (correlation between the parameter and the error term), only Z-scores below 1 were considered as satisfactory. Only two labs showed acceptable systematic errors for all three enzymes, i.e. average Z-score always less than 1. Even though the number of lab partecipating to the ring-test was small, some trends emerged: i) systematic errors appear to be mainly soil-dependent, i.e. generally each lab among soils indifferently overestimated or underestimated any enzymatic activity; ii) random error was more lab-dependent than enzyme-dependent; iii-beta-glucosidase is the enzyme which measurement is, in general, less variable among labs. This inter-laboratory comparison improved participants awareness about soil enzyme assays meaning and is also the starting point to identify critical steps for setting up more reliable protocols.

La stabilizzazione della sostanza organica del suolo è legata a meccanismi chimici e chimico-fisici che la rendono meno facilmente attaccabile dai microrganismi. Con la podzolizzazione si assiste all’incremento del carbonio organico degli orizzonti profondi, grazie alla migrazione di complessi organo-metallici. In tali orizzonti, la sostanza organica risulta tipicamente più stabile, sia per la minore attività microbica rispetto ad orizzonti più superficiali, sia per le forti interazioni che si stabiliscono tra composti organici e fasi minerali. Poiché la presenza dei diversi orizzonti genetici negli Spodosuoli (Bs, Bhs, Bsm) rappresenta successive fasi di sviluppo con variazioni nel rapporto C/metallo, è lecito aspettarsi che i meccanismi di stabilizzazione assumano un peso diverso in funzione della fase pedogenetica. Per verificare questa ipotesi sono stati selezionati gli orizzonti B di suoli a diversa intensità livello di podzolizzazione: dal Bw di uno Spodic Dystrudept al Bsm di un Placic Cryaquod; i campioni sono stati sottoposti ad ossidazione con NaClO e demineralizzazione con HF. Il metodo permette di suddividere la SOM in 3 frazioni: ossidabile, stabilizzata per interazione con i minerali e chimicamente recalcitrante. Le ossidazioni chimiche sono state effettuate a due diverse concentrazioni di NaClO (6 e 1%) e confrontate con una ossidazione biologica valutata in termini di respirazione potenziale. L’ossidazione con NaClO 6% è risultata molto esaustiva, rimuovendo percentuali di C sempre superiori al 78% senza relazioni evidenti con l’intensità della pedogenesi. La frazione stabilizzata raggiunge valori pari al 10% nel caso del Bsm e quella recalcitrante è massima negli orizzonti dei suoli meno evoluti. Risultati più interessanti si ottengono impiegando l’ossidante in condizioni più blande: la frazione ossidabile varia da valori medi del 50% nei B dei suoli meno evoluti al 34% nel Bsm. Lo stesso trend è evidenziabile dalle cinetiche di ossidazione biologica con valori percentuali del carbonio potenzialmente mineralizzabile comprese tra 1.7 e 4.1%. La stabilizzazione per interazione tra composti organici e fasi minerali riflette bene il procedere della podzolizzazione: varia infatti dal 27 al 56% secondo l’ordine Spodic Dystrudept, Typic Haplocryod, Placic Cryaquod. Con il procedere della podzolizzazione, si assiste quindi ad una sempre maggiore stabilizzazione chimico-fisica della sostanza organica nell’orizzonte B, che culmina con la formazione dell’orizzonte cementato. La stabilizzazione per recalcitranza chimica risulterebbe di qualche entità solamente nelle prime fasi. La frazione ossidabile chimicamente è sempre piuttosto elevata, ma solo una minima percentuale è biologicamente ossidabile, confermando ulteriormente la stabilizzazione ad opera di interazioni organo-minerali.

The aim of the present study was t investigate the microbial activity along forest brown soil profiles sequence developed on different litological substrates (carbonate or non-carbonated cement in sandstone formations) at different altitudes. The main question posed was: does carbonate affect the biochemical activity of brown soil profiles at different altitudes? For the purpose of this study, four soil profiles with different amounts and compositions of SOM developed on different lithological substrates were selected: two with carbonate (MB and MZ) and the other two with non-carbonated cement in the sandstone formations (MF1andMF2). Chemical and biochemical properties of soil were analysed along soil profiles in order to assess the SOM quantity and quality, namely total organic C (Corg), water extractable organic C (WEOC) and humification indices (HI, DH, HR). Microbial biomass (Cmic and Nmic) content, as well as the specific activities of acid phosphatase, b-glucosidase and chitinase enzymes were chosen as indicators of biochemical activity. The soil biochemical properties provided evidence of better conditions for microorganisms in MB than in MF1, MF2 and MZ soil profiles, since patterns of microbial biomass content and activity might be expected in response to the amount and quality of organic substances. The different lithological substrates did not show any clear effect on soil microbial biomass content, since similar values were obtained in MF1, MF2 (with non-carbonated cement) and MZ (with carbonate). However, the specific activities of acid phosphatise (per unit of Corg and per unit of Cmic) were higher in soils with no carbonate (MF1 and MF2) than in soil with carbonate (MB and MZ). In conclusion, the biochemical activity along brown soil profiles was mainly regulated by different soil organic matter content and quality, while the two different lithological substrates (with carbonate or non-carbonated cement in the sandstone formations) did not show any direct effect on microbial biomass and its activity. However, the activity of acid phosphatise per unit of C was particularly enhanced in soil with non-carbonate cement in the sandstone formations.

Afin de caractériser l'effet rhizosphérique d'Acacia tortilis subsp. raddiana, la biomasse microbienne, sa diversité et son activité métabolique ainsi que l'activité de quelques enzymes impliquées dans le cycle de l'azote et du phosphore ont été comparées dans des sites soumis à l'influence du système racinaire et dans des sites témoins de deux biotopes situés au nord et au sud du Sahara.Les résultats montrent que presque tous les paramètres suivis sont modifiés par le système racinaire d'Acacia raddiana. Cet effet rhizosphérique varie en fonction de la distance au tronc, de l'âge du peuplement et des conditions trophiques stationnelles. Des différences notables ont été mises en évidence entre les biotopes sénégalais et tunisiens : l'activité métabolique des micro-organismes est largement supérieure dans ces derniers. La sensibilité des bio-indicateurs dans ces milieux extrêmes est par ailleurs discutée. In order to test the quality and the characteristics of north and south Saharian soils in the presence of Acacia tortilis subsp. raddiana root system, microbial biomass, microbial respiration, several enzymatic activities, microbial physiological groups and their ammonification-nitrification potential in the rhizosphere were compared with those in a distant zone of soil not influenced by the plant.Almost all the chemical, biochemical and microbiological parameters were influenced by the Acacia root system. This « rhizosphere effect » can be affected by several variables. Thus, it depends on the distance from the base of the tree, the age of the planting and the local ecological conditions. Noticeable differences were found between the south and the north areas: in these latter the microbial metabolic activities are higher. The bioindicators sensibility in these oligotrophic environments is also discussed.

The experiment was carried out on a short rotation coppice culture of poplars (POP-EUROFACE, Central Italy), growing in a free air carbon dioxide enriched atmosphere (FACE). The specific objective of this work was to study whether elevated CO2 and fertilization (two CO2 treatments, elevated CO2 and control, two N fertilization treatments, fertilized and unfertilized), as well as the interaction between treatments caused an unbalanced nutritional status of leaves in three poplar species (P. x euramericana, P. nigra and P. alba). Finally, we discuss the ecological implications of a possible change in foliar nutrients concentration. CO2 enrichment reduced foliar nitrogen and increased the concentration of magnesium; whereas nitrogen fertilization had opposite effects on leafnitrogen and magnesium concentrations. Moreover, the interaction between elevated CO2 and N fertilization amplified some element unbalances such as the K/N-ratio.

The aim of this study was to evaluate chemical changes in soil organic matter (SOM) in organically and conventionally managed fields, using pyrolytic indices and the extraction of different carbon fractions. Pyrolysis-gas chromatography (Py-GC) was used to study structural changes in SOM, whereas the different soil extractions gave a fractionation of C forms. Organic management increased both humic and labile C forms (microbial biomass C and water soluble organic C). A significant positive relationship was found between the living SOM fraction, expressed as microbial biomass/total organic C ratio (MBC/TOC) and humification rate. A negative relationship was found between the pyrrole to phenol ratio (O/Y) and total extractable C (TEC). An opposite trend has been observed for the second pyrolytic index (N/O), which represents the mineralization of fresh organic matter. Mineralization was higher in organically managed soil, probably because of consistent input of fresh material to the organic field. Carbon fraction pools and pyrolytic indices provided complementary indications of SOM quality under organic and conventional management.