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Climate change is likely to impact the dynamics of carbon and water cycles in forests over the next century. To date, it is still debated how forests will react. Some key variables may help in understanding the extent at which terrestrial ecosystems will be affected. Carbon Use Efficiency (CUE) and Water Use Efficiency (WUE) represent some of these key aspects. CUE represents the capacity of the forests to transfer carbon from the atmosphere to the terrestrial biomass, WUE the carbon gained for the water lost via canopy transpiration. Hence, both are key variables since they intimately represent the effects of several coupled ecophysiological processes affected by climate change. Here, we analyzed how within the 3D-CMCC-CNR FEM, forced by five general circulation model data and the four representative concentration pathways, the modeled CUE and WUE are affected by, from seasonal to over medium- and long-time period, warming, rising atmospheric [CO2] and management, assessing at which extent each component influences model results in an existing boreal forest in Finland. The 3D-CMCC-CNR FEM model results reveal that CUE tends to decrease with warmer scenarios, and management may greatly dampen the effects but only in the short- to medium-time period. WUE can increase consistently owing to the increasing of the CO2 fertilization if coupled with management. These results confirm also, at stand spatial scale resolution, what found globally in other recent studies and suggesting to consider for long-term period alternative forest management practices to enhance these effects in mitigating climate change.

Da qualche decennio gli studi sulle cause e gli e etti dei cambiamenti climatici sono diventati oggetto di discussione non solo in ambito ambienta- le ma anche in molte altre discipline (economia, sociologia, medicina, etc.). L'aumento dell'anidride carbonica (CO2) in atmosfera e considerato uno dei principali fattori che in uenza il cambiamento del clima, e di conseguenza gran parte degli sforzi della comunit a scienti ca si sono rivolti allo studio dei meccanismi che regolano ed in uenzano il ciclo del carbonio. Gli ecosi- stemi terrestri sono una delle principali componenti del ciclo del carbonio; essi infatti attraverso i processi di fotosintesi e respirazione sono in gra- do di assorbire o emettere CO2 in atmosfera contribuendo direttamente al bilancio del carbonio Carbon Balance (CB). Una delle principali tecniche utilizzate per la misura dello scambio di CO2 tra gli ecosistemi terrestri e l'atmosfera e la tecnica della correlazione turbolenta (Eddy Covariance, EC). Attraverso le misure EC, oltre a misurare gli scambi di CO2, e sta- to possibile sia quanti care e comprendere il ruolo degli ecosistemi terrestri nel ciclo del carbonio ma anche sviluppare, validare ed applicare un'ampia gamma di modelli. Le misure EC prima di essere utilizzate necessitano di una serie di correzioni. Una prima fase di correzioni riguarda i dati misurati direttamente in campo (raw data) mentre una seconda fase, detta di post processamento, ltra i raw data aggregati ad una scala temporale semio- raria. Per il post processamento sono state proposte diverse metodologie di ltraggio. Non essendo possibile decidere a priori quale delle combinazioni di ltraggio sia pi u corretta, le di erenze dei risultati devono essere considerate ed interpretate come incertezza. L'obiettivo principale della presente tesi di dottorato e quello applicare diversi schemi di post processamento, quanti- carne l'incertezza ed attribuire, ad ogni fase del post processamento, un peso rispetto all'incertezza globale. Dopo la quanti cazione dell'incertezza l'attenzione e stata rivolta sia a quanti care l'impatto che i diversi schemi di post processing hanno sul bilancio del carbonio annuale ma anche a de nire l'incertezza intrinseca dei fattori del post processing che causano la maggior divergenza. Per avere un esempio dell'impatto che l'incertezza del post pro- cessamento dei dati EC ha in fase applicativa i risultati dei diversi schemi sono stati utilizzati per parametrizzare delle curve di luce. La scelta di un diverso schema di post processamento causa delle divergenze dei risultati nali ed ha un notevole impatto sulla parametrizzazione delle curve di luce. Il principale fattore di incertezza e la soglia di u* utilizzata per eliminare i dati misurati in periodi di bassa turbolenza. Per i siti anno analizzati i valori medi annuali di NEE (scambio netto di CO2 tra ecosistema ed atmosfera), respirazione e GPP (produzione primaria lorda) sono compresi, rispettiva- mente, tra -60 e -900, +800 e +1800 e +1000 e +2000 gC m 2. Le di erenze tra i valori annuali e le medie per i ussi di NEE sono pari a 50 gC m 2 mentre per Reco e GPP sono intorno a 150 gC m 2. Questi risultati di- mostrano che la scelta di un diverso schema di post processamento dei dati EC ha un notevole impatto sull'incertezza globale e sul bilancio del carbonio. For several decades studies on the causes and e ects of climate change have become the subject of discussion not only in environmental sciences but also in many other disciplines (economics, sociology, medicine, etc..). Among the causes of climate change, the increase of carbon dioxide (CO2) into the atmosphere, is considered one of the main factors that a ect this phenomenon, then, most of the scienti c community's e orts are directed to an improved understanding of the mechanisms that regulate and in uence the carbon cycle. Terrestrial ecosystems are a major component of the car- bon cycle en e ect, through the processes of photosynthesis and respiration, are able to sink or source CO2 into the atmosphere and directly in uen- cing the Carbon Balance (CB). One of the main techniques used to measure CO2 exchange between terrestrial ecosystems and the atmosphere is (Ed- dy Covariance, EC). With the EC measurements, in addition to measuring the exchange of CO2, it was possible to quantify and understand the role of terrestrial ecosystems in the carbon cycle but also to develop, validate and apply a wide range of models. The EC measurements, before their use, require some corrections. A rst phase of corrections cover data measured directly in the eld (raw data) and a second phase, named post-processing, ltering the raw data aggregated to a half hour time scale. For the post- processing have proposed various methods of ltering. Since you can not decide a priori which of the combinations of ltering is more correct, the dif- ferences in results must be considered and interpreted as uncertainty. The main objective of this thesis is to apply di erent patterns of post processing, to quantify the uncertainty and attribute, at each step of post processing, a weight than overall uncertainty. After the quanti cation of uncertainty the attention was paid both to quantify the impact that di erent patterns of post processing have on the annual carbon balance but also to de ne the intrinsic uncertainty of the post processing factors that cause the most di- sagreement. For an example of the impact that the uncertainty of the post processing of the EC data has during the application phase the results of di erent schemes have used to parameterize the light-response curve. The choice of a di erent pattern of post-processing due to the di erences of the nal results and have a considerable impact on the parameterization of the light-response curve. The main factor of uncertainty is the threshold of u* used to delete the data measured in periods of low turbulence. For the sites analyzed years the average annual NEE (net exchange of CO2 between eco- systems and atmosphere), respiration and GPP (gross primary production) include, respectively, between -60 and -900, +800 and +1800 to +1000 and +2000 gC m 2. The di erences between the values and annual average ows for NEE are 50 gC m 2 while for Reco and GPP are around 150 gC m 2. These results demonstrate that the choice of a di erent pattern of post-processing EC data has a signi cant impact on the uncertainty on the global carbon balance. Dottorato di ricerca in Ecologia forestale

This paper describes the formation of, and initial results for, a new FLUXNET coordination network for ecosystem-scale methane (CH4) measurements at 60 sites globally, organized by the Global Carbon Project in partnership with other initiatives and regional flux tower networks. The objectives of the effort are presented along with an overview of the coverage of eddy covariance (EC) CH4 flux measurements globally, initial results comparing CH4 fluxes across the sites, and future research directions and needs. Annual estimates of net CH4 fluxes across sites ranged from −0.2 ± 0.02 g C m–2 yr–1 for an upland forest site to 114.9 ± 13.4 g C m–2 yr–1 for an estuarine freshwater marsh, with fluxes exceeding 40 g C m–2 yr–1 at multiple sites. Average annual soil and air temperatures were found to be the strongest predictor of annual CH4 flux across wetland sites globally. Water table position was positively correlated with annual CH4 emissions, although only for wetland sites that were not consistently inundated throughout the year. The ratio of annual CH4 fluxes to ecosystem respiration increased significantly with mean site temperature. Uncertainties in annual CH4 estimates due to gap-filling and random errors were on average ±1.6 g C m–2 yr–1 at 95% confidence, with the relative error decreasing exponentially with increasing flux magnitude across sites. Through the analysis and synthesis of a growing EC CH4 flux database, the controls on ecosystem CH4 fluxes can be better understood, used to inform and validate Earth system models, and reconcile differences between land surface model- and atmospheric-based estimates of CH4 emissions.

The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible., Scientific Data, 7, ISSN:2052-4463

Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH4 Version 1.0, the first open-source global dataset of CH4 EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH4 fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH4 representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH4 Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH4 emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH4 fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH4 emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20∘ S to 20∘ N) the spring onset of elevated CH4 emissions starts 3 d earlier, and the CH4 emission season lasts 4 d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH4 emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH4 emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH4 emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH4 emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH4 modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH4 peak). FLUXNET-CH4 is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH4 cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at https://doi.org/10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH4 data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper., Earth System Science Data, 13 (7), ISSN:1866-3516, ISSN:1866-3508

The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.

Process-based vegetation models are widely used to predict local and global ecosystem dynamics and climate change impacts. Due to their complexity, they require careful parameterization and evaluation to ensure that projections are accurate and reliable. The PROFOUND Database (PROFOUND DB) provides a wide range of empirical data on European forests to calibrate and evaluate vegetation models that simulate climate impacts at the forest stand scale. A particular advantage of this database is its wide coverage of multiple data sources at different hierarchical and temporal scales, together with environmental driving data as well as the latest climate scenarios. Specifically, the PROFOUND DB provides general site descriptions, soil, climate, CO$_{2}$, nitrogen deposition, tree and forest stand level, and remote sensing data for nine contrasting forest stands distributed across Europe. Moreover, for a subset of five sites, time series of carbon fluxes, atmospheric heat conduction and soil water are also available. The climate and nitrogen deposition data contain several datasets for the historic period and a wide range of future climate change scenarios following the Representative Concentration Pathways (RCP2.6, RCP4.5, RCP6.0, RCP8.5). We also provide pre-industrial climate simulations that allow for model runs aimed at disentangling the contribution of climate change to observed forest productivity changes. The PROFOUND DB is available freely as a “SQLite” relational database or “ASCII” flat file version (at https://doi.org/10.5880/PIK.2020.006/; Reyer et al., 2020). The data policies of the individual contributing datasets are provided in the metadata of each data file. The PROFOUND DB can also be accessed via the ProfoundData R package (https://CRAN.R-project.org/package=ProfoundData; Silveyra Gonzalez et al., 2020), which provides basic functions to explore, plot and extract the data for model set-up, calibration and evaluation.

Methane (CH$_{4}$) emissions from natural landscapes constitute roughly half of global CH$_{4}$ contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH$_{4}$ flux are ideal for constraining ecosystem-scale CH$_{4}$ emissions due to quasi-continuous and high-temporal-resolution CH$_{4}$ flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH$_{4}$ Version 1.0, the first open-source global dataset of CH$_{4}$ EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH$_{4}$ fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH$_{4}$ representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH$_{4}$ Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH$_{4}$ emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH$_{4}$ fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH$_{4}$ emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20�� S to 20�� N) the spring onset of elevated CH$_{4}$ emissions starts 3 d earlier, and the CH$_{4}$ emission season lasts 4 d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH$_{4}$ emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH$_{4}$ emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH$_{4}$ emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH$_{4}$ emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH$_{4}$ modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH$_{4}$ peak). FLUXNET-CH$_{4}$ is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH$_{4}$ cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at https://doi.org/10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH$_{4}$ data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper.

15 Pág. Ecological Modelling, Tree species mixing of oak (Quercus petraea (Matt.) Liebl./Quercus robur L.) and pine (Pinus sylvestris L.) has been shown to have positive effects on ecosystem service provision. From a management perspective, however, it is still uncertain which thinning regime provides the highest possible productivity of mixed oak–pine forests in the long term. Because of a lack of empirical studies dealing with thinning and species mixing effects on oak–pine forests, we simulated forest growth in order to test which thinning type and intensity may provide the highest productivity in the long-term. To achieve this, we simulated the growth of pure and mixed stands of oak and pine for 100 years in 23 triplets located on an ecological gradient across Europe. For this purpose, we applied four different growth simulators and compared their results: the distance-independent single-tree simulator PROGNAUS, the distance-dependent single-tree simulator SILVA, the gap model ForCEEPS, and the process-based simulator 3D-CMCC-FEM. We investigated the effects of species mixing and thinning from the upper (thinning from above) and lower tail (thinning from below) of the diameter distribution by reducing the stand basal area to 50 and 80% of the maximum basal area. We compared simulated results of the relative volume productivity of mixed versus pure stands and of thinned versus unthinned stands to empirical results previously obtained on the same set of triplets. Simulated relative volume productivity ranged between 61 and 156%, although extremes of 10% and of 300% could be observed. We found the relative volume productivity to be influenced by stand age, but not by stand density, except for PROGNAUS. Relative volume productivity did not increase with the site water supply of the triplet location. Highest long-term productivity for oak, pine and oak–pine stands can be expected in consequence of thinning from above, but the effect of thinning intensity differed between simulators. Thinning effects were positively affected by stand density, but not by stand age, except for thinning from above predicted by PROGNAUS. Predicted thinning effects showed good approximation of results from thinning experiments for oak, but not for pine stands. We hypothesize the results might be caused by the insufficient simulator representation of climate and its interaction with other site variables and stand structure. Further work is needed to reduce the revealed limitations of the existing growth models, as we currently see no alternative to such kind of studies and simulators., The authors thank the European Union for funding the project “Mixed species forest management. Lowering risk, increasing resilience (REFORM)” under the framework of Sumforest ERA-NET. The authors from Austria also thank the Austrian Federal Ministry for Sustainability and Tourism for supporting the establishment of the Austrian triplet plots and for covering the work expenses of Markus Engel within the project ”Forstwirtschaft mit Mischwäldern – geringes Risiko, hohe Widerstandskraft – REFORM” under the grant number 101199. All contributors thank their national funding institutions to establish, measure and analyze data from the triplets. Maude Toïgo and Xavier Morin thank François de Coligny and Nicolas Beudez for their help in the development of the ForCEEPS model. Antonio Tomao, Carlo Trotta and Anna Barbati thank Alessio Collalti for his support and suggestions about the simulations with the 3D-CMCC-FEM model.

PURPOSE OF INVESTIGATION: Aim of the study was to evaluate the possible involvement of zinc in the complex pathogenic process behind the onset and perpetuation of endometriotic lesions. To study the level of zinc serum between a group of patients affected by endometriosis and a group of healthy patients. MATERIALS AND METHODS: The study included 86 women: 42 patients whose histodiagnosis had revealed pelvic endometriosis and 44 healthy patients. The authors measured the serum zinc concentration for all patients. RESULTS: The group of patients with endometriosis presented serum zinc concentration of 1010 +/- 59.24 microg/l. The observation group presented a serum zinc concentration of 1294 +/- 62.22 microg/l. CONCLUSION: The results showed that serum zinc levels in women with endometriosis are decreased and this seems to actually confirm that this microelement can possibly affect the multifactorial pathogenesis of the disease. As a matter of fact, zinc interferes with many biological processes, among which inflammation and immunity, which seem to be the base of the development of the lesions. Therefore, the authors believe that this hypothesis requires more attention and further investigation to determine its reasonableness. If the results are confirmed, this study opens up future prospects as for the treatment of endometriosis, taking into account also the role of zinc in the onset of male sterility and the development of testicles. Zinc could in fact be used as marker to detect women at high risk of endometriosis and for the elaboration of a new treatment for sterility, from which these women often suffer.