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Understanding and quantifying hydrology processes represent a mandatory step in semi-arid and arid regions for defining the vulnerability of these environments to climate change and human pressure, as well as for providing useful data to steer mitigation and resilience strategies. This generally valid concept becomes even more stringent for highly sensitive ecosystems, such as small islands.It is the case of Pianosa Island (Tuscan Archipelago) that extends a few more than 10 km2 within the Tyrrhenian Sea and it is characterised by a flat morphology (maximum altitude 29 m a.s.l.) and semi-arid climate conditions (550 mm and 17 °C as mean annual precipitation and temperature).Because of the morphology and the medium-high permeability of superficial bio-calcarenite rocks, superficial water are absent. Nevertheless, the peculiar geological-hydrogeological setting guarantee a storage of groundwater in a phreatic aquifer and semi-confined/confined system, hitherto able to satisfy the local human water demand, mainly tied to seasonal tourism (thousands of visitors/year) and domestic exigencies (less than 30 permanent people). Evapotranspiration represents the most important voice of the water budget, given the windy and relative high temperature conditions.In the precarious hydro-equilibrium for biosphere and human communities, and considering sea-level rise and climate regime trends that the Mediterranean is experiencing, HYDRO-ISLAND project (UNESCO’s program) intends to deploy a multi-disciplinary approach (geology, hydrogeology, geochemistry, geophysics, remote sensing-smart technology) for better understanding and quantifying the hydrological processes affecting the water availability and for sharing data and transfer knowledge to the community and younger generations, possibly suggesting best practices for water sustainability.First results pointed out as over the last decade the annual rainfall weakly tended to increase, but at the same time such increasing resulted concentrated in summer and autumn seasons, whereas during winter and spring a decreasing tendency is even observed. This precipitation regime has led to a major rate of evapotranspiration and minor effective infiltration that caused a decreasing of piezometric level over several years. Quantity and chemical-isotopic features of rainfall and effective infiltration water measured/collected by a raingauge and a high precision lysimeter describe the hydrological processes at soil level and characterize the rate and seasonality of groundwater recharge in an experimental site. Using multispectral data by drone, we are trying to extend the experimental site information to a wider area in order to understand the general behaviour at island scale. Measurements, water sampling and analyses for shallow and deep wells, together with the study of geological constraints, are highlighting the distribution and relationship among different groundwater components, including the seawater that intrudes the aquifer from the SE side of the island. Furthermore, the comparative analyses of continuative data monitoring in wells and weather station showed the presence of possible concentrated water infiltration processes during rainfall extreme events that induce a quick response of groundwater systems in terms of water level rise and decrease of electrical conductivity. Thus, elements of vulnerability of the aquifer to pollution are pointed out, as well as the possibility to provide technical solutions for enhancing water infiltration and groundwater availability.

Surface water and groundwater are changing rapidly because of significant climate warming in the Arctic region [1,2]. Arctic amplification has intensified the melting of snow cover and glaciers, as well as widespread permafrost degradation, leading to a prominently increase of the annual discharge of some Arctic rivers [3,4]. This results in dramatic impacts on the surface water transition and freshwater circulation that, in turn, can cause localized permafrost thaw [5], allowing greater connection between deep groundwater and surface water pathways. Groundwater is a crucial component of the hydrological cycle, affecting ecosystems and human communities in Arctic regions.In high-latitude regions, evaluating groundwater flux and storage and river discharge is challenging due to a lack of trusted and publicly available hydrogeological data. Changes in river flows and groundwater discharge will alter fluxes of freshwater and terrigenous material (e.g., sediment, nutrients, and carbon), with implications for biodiversity in both freshwater and marine ecosystems. The rapid glacier melting affects weathering processes, resulting in the mobilization-transport of pollutants, microorganisms stored for a long time, and turbid meltwaters. Consequently, more timely and accurate evaluation of surface and groundwater is urgently required.Thanks to its geographical characteristics, the retreating glaciers, the research stations and infrastructures, and the studies carried out in the past and present, the Bayelva catchment near Ny-Ålesund (Western Svalbard-Norway) is an ideal site for surveys aimed at increasing knowledge on hydrology dynamics and associated effects, in the continuum from glaciers to the fjord.In this framework, within the ICEtoFLUX project (MUR/PRA2021 project-0027) field campaigns were conducted in the spring and summer of 2022 in the Bayelva River catchment, from its glaciers and periglacial/proglacial systems up to the Kongsfjorden sector significantly affected by the river. The activities were aimed at quantifying hydrologic processes and related transport of pollutants and microbial biomass and activities. Suprapermafrost groundwater was monitored by four piezometers installed along a hillslope to investigate how subsurface and surface waters interact during active layer development.Water samples were repeatedly collected for analysing physical-chemical-isotopic-biological parameters. Main rain events and monthly total precipitation were sampled for stable isotopes.The first results suggest that, in general, electrical conductivity and total suspended solids increase from the glacier to the Bayelva monitoring station, which is located less than 1 km far from the coast. Seasonal evolution of physical-chemical features was also observed. Results from piezometers indicate that the underground flow is spatially and temporally heterogeneous, both quantitatively and from a physical-chemical-isotopic-biological point of view. A general increase of electrical conductivity over the melt season was registered for groundwater and streamwater. First evidence on organic pollutants and microbe transport are also discussed.[1] Fichot, C.G. et al. 2013. Sci. Rep., 3, 1053.[2] Morison, J. et al. 2012. Nature, 481, 66–70.[3] McClelland, J.W. et al. 2006. Geophys. Res. Lett., 33, L06715.[4] Wang, P. et al. 2021. Res. Lett., 16, 034046.[5] Zheng, L. et al. 2019. J. Geophys. Res. Earth Surf., 124, 2324–2344.

Wildfires are recognized as one of the most affecting ecological agents, altering geomorphological processes, hydrologic cycles, and water quality. On average from 50,000 to 65,000 fires occur in Europe every year, burning approximately 500,000 ha of forested areas. Between September 2018 and February 2019 two large wildfires burnt nearly 1,400 ha of forests and farmlands in the Pisano Mount area (northwestern Tuscany). The mountainous morphology of the area linked to the proximity to the sea causes high precipitation variability and intensity. This, joined with low permeability bedrock (mainly quartzites, schists, and phyllites) and with the extensive vegetation coverage, make the study site a hot spot for surface waters analysis. Moreover, burnt catchments are of primary importance in the recharge processes of the groundwater resources of the costal plain, which are exploited by a large number of inhabitants and agricultural facility. Consequently, the present study is aimed at understanding and quantifying the wildfire impacts on the hydrogeological dynamics and water quality in the studied catchments. Such impacts are being evaluated by comparing burnt and unburnt catchments, which were selected to be as similar as possible from geological, morphological, and vegetational perspectives. The multi-parameter selection method involved Principal Component Analysis and Distance analysis on many potentially feasible catchments. A network of automatic monitoring instruments was deployed on site. Five hydraulic sections of the main streams draining the area were monitored for hydraulic level and physico-chemical parameters. Hydrographs analysis was performed to infer differences in hydrogeological dynamics between burnt and unburnt basins. Monthly samples were collected for stream water and groundwater chemical analysis. In addition, four plate lysimeters were installed to sample soil water for its chemical characterization. The chemical analysis involved major anions and cations, trace elements, water isotopes, and organic compounds, to search for chemical perturbation potentially arising from the wildfire. The investigation highlighted various differences between the burnt and unburnt basin, mainly for the surface waters. The streams draining the burnt areas present different hydraulic behaviour and changes in physiochemical parameters in response to rainfall events. Moreover, the yearly variation of physiochemical parameters and chemical characteristics present an higher variance for those streams draining wildfire affected catchments.

The stable presence of humans in the Alps dates back to the Bronze Age and peaked in the mid-19th century, deeply shaping the landscape and allowing the co-evolution of numerous plant and animal species. Since the 1950s, socio-economic changes have led to the gradual depopulation of mountain areas, and the consequent abandonment of traditional agro-pastoral activities. The rupture of the long-established balance between man and nature has triggered a process of transition, further exacerbated and accelerated by climate change. The Belmont Forum project ABRESO (Abandonment and rebound: Societal views on landscape and land-use change and their impacts on water and soils) started in 2021 and aims at advancing the understanding of mitigation and adaptation strategies to environmental change, through an international partnership involving five countries (the United States, France, Italy, Japan and Taiwan). Italy contributes to the project with three case studies: Gran Paradiso National Park, Val Grande National Park and the Tesino highlands are investigated in the Italian Alps. Using an interdisciplinary approach, the project aims to study the impact of the abandonment of traditional activities on ecosystem services provisioning, such as biodiversity conservation and soil sustainability, as well as the actual perception of the ongoing environmental changes by different stakeholders and its subsequent integration into local land management practices and policies. The land use and land cover change occurring due to land abandonment can have profound implications in the critical zone (CZ), inducing changes in soil, vegetation, carbon fluxes and water resources. This project integrates the natural and social sciences approaches to study the evolution of ecosystems in response to these factors. More specifically, advanced techniques that integrate Earth Observation, biogeochemical analyses and socio-economic investigation are used in the Italian sites to understand in which extent geo-biophysical and social landscapes reciprocally interact. The environmental variables collected for ecosystem monitoring and to study and upscale the ongoing dynamics in the CZ include snow cover and phenology parameters, soil organic carbon, and land use change maps extracted from time series of satellite imagery, validated via in situ measurements. Then, the observed processes will be compared to the perception of different stakeholders (local population, policy makers, tourists, business keepers, etc.) to unveil new insights into the way land use change in the mountain areas influence and is influenced by the local land management practices and policies.

Presentation was presented at the Arctic Science Summit Week 2023 (ASSW2023)that took place in Vienna, Austria on February 17-24, 2023 (February 21th, 2023). The presentation includes a synthesis of the published work ofMagnaniet Al.,2022,"Microscale drivers of summer CO2fluxes in the Svalbard High Arctic tundra" (Sci Rep) and subsequent analysis performed onto the 2021-2022 datasets.&nbsp

Presentation made on 11/01/2023 within the workshop Towards an Arctic Critical Zone Observation Network (ACZON)

This technical note (in Italian) describes how to calibrate portable flux chambers equipped with IRGA for the measurement of CO2 fluxes from soil. An English version is in progress.

The continuous acquisition of CO2 soil flux data has been started on Mt Etna in November 2021, with the aim of assessing a first balance between CO2 from volcanic and biological origin. Our long-term goal is an interdisciplinary study of volcanic, biological, ecological, biogeochemical, climatic and biogeographical aspects, including the anthropogenic impact on the environment. All aspects are integrated in the study of the so-called Critical Zone, i.e. the layer between the deep rock and the top of the vegetation where the main biological, hydrological and geological processes of the ecosystem take place. The new research activity at Mt Etna is performed within the framework of the PON-GRINT project for infrastructure enhancement (EU, MIUR), and it adds up to activities going on at Grand Paradiso National Park (Italian Alps), and Ny Alesund (Svalbard, NO, High Arctic) in the framework of the IGG-CNR Critical Zone Observatories.During the first phase of the project, two fixed stations were installed in two sites at Piano Bello (Valle del Bove, Milo), in an area where the endemic Genista aetnensis grows. An Eddy Covariance system for net CO2 ecosystem exchange measurement and a weather station will be installed in 2022. Carbon stable isotopes data will be acquired periodically using in-situ instrumentation (i.e. Delta Ray). The installation sites are selected after CO2 soil flux surveys around the volcano using a portable accumulation chamber. The two stations installed at Piano Bello consist of an automatic accumulation chamber fixed to the ground, a mobile lid with a diffusion infrared sensor for measuring CO2, a data logger and a sensor for measuring soil moisture and temperature. The accumulation chambers are programmed to acquire data on ecosystem respiration every hour for all day. Data are transmitted to the IGG data collection center. The new IGG-CNR Mt Etna CZO will contribute investigating CO2 fluxes at the soil-vegetation-atmosphere interface in different geological and environmental contexts. We benefit from the collaboration with the National Institute of Geophysics and Volcanology (INGV), the Ente Parco dell'Etna, and the Dipartimento Regionale dello Sviluppo Rurale e Territoriale di Catania.

There is still a paucity of hydrological data explaining the relationship between (rapid, millennial‐scale) climate forcing and Mediterranean rainfall since the Last Glacial. We show that distinct lake‐level fluctuations at Lake Trasimeno (Italy) are associated with changing aridity in the central Mediterranean during the last ~47 800 years. The lake‐level fluctuations are reconstructed based on carbonate mineral content and carbonate mineral species, as well as the stable oxygen and carbon isotope (δ18O and δ13C) geochemistry of endogenic carbonates. Low lake levels are linked to high carbonate, Mg‐calcite and aragonite contents, and high δ18O and δ13C values. Inferred hydrological changes are linked to glacial–interglacial and, tentatively within the limitations of our chronology, to millennial‐scale climate variability as well as the intensity of the Atlantic Meridional Overturning Circulation (AMOC). Prior to the Last Glacial Maximum (LGM), during intervals equivalent to Marine Isotope Stage 3 (MIS 3), a stronger AMOC associated with Greenland interstadial periods (Dansgaard/Oeschger (D/O) warm periods) and stronger Asian monsoon probably coincide with increased precipitation in central Italy as inferred from high lake levels at Lake Trasimeno. Periods of weak AMOC intensity such as during Greenland stadials (D/O cold periods), during Heinrich events, and weak Asian monsoons are correlated with lake level lowstands, which imply relatively dry conditions in central Italy. Lake Trasimeno’s water level during the LGM and the Lateglacial (MIS 2) is relatively stable, with recorded changes showing distinct similarities to orbital configurations. Although muted, high latitude climate forcing is still evident in the data during peak glacial conditions. The transition from D/O‐like hydrological variability at Lake Trasimeno during MIS 3 to orbitally controlled fluctuations during the Lateglacial to Holocene transition coincides with an increasing amplitude in local winter and summer insolation, probably indicating increasing seasonality and a larger temperature gradient between low‐ and high‐latitude settings., Deutscher Akademischer Austauschdienst http://dx.doi.org/10.13039/501100001655

Kongsfjorden (Svalbard archipelago) is subjected to strong environmental gradients creating high physical and geochemical stress on benthic faunas. The present study aims at understanding the environmental drivers governing benthic foraminifera in the innermost part of the fjord. Surface sediments from 9 stations were sampled during August 2018 along a transect starting at ca. 2 km from the tidewater glacier Kronebreen and ending 12 km seaward. Three biozones were identified in response to disturbances linked to the proximity of the Kronebreen front (i.e., high water turbidity, freshwater, and sediment inputs, reduced organic fluxes). Close to the terminus (proximal biozone), few stress-tolerant and glacier proximal species were present (i.e., Capsammina bowmanni and Cassidulina reniforme). At about 6-8 km from the front (medial biozone), reduced turbidity, and increased organic fluxes, resulted in a higher diversity, and a high abundance of the phytodetritus-indicator Nonionellina labradorica. Relatively high diversity persisted until 12 km from the front due to higher organic inputs and reduced stressful conditions. The distal biozone was dominated by the Atlantic Water (AW) indicator Adercotryma glomeratum, in coherence with the presence of warm and salty AW detected far inside the fjord. Physical stress related to the glacier dynamics appears to favour the establishment of opportunistic species close to the terminus, whereas reduced disturbance away from the glacier induces the establishment of diverse assemblages. Our results show that benthic foraminifera may be effective bioindicators to monitor the long-term retreat of tidewater glaciers induced by climate change in Kongsfjorden.

Lake Orhid, located at the border between Albania and the Former Yugoslavian Republic of Macedonia (FYROM), is a lake of outmost ecological importance because of their unique geological and ecological characteristics. It is a hotspot of freshwater biodiversity, it is the habitat for more than 210 endemic species of high economical and cultural value, and it provides many diverse and valuable Ecosystem Services (ESS), as sustainable tourism, food production and supply of freshwater. Among these, the provision of habitat for iconic species is a characteristic ESS. The dynamic of its supporting functions is object of study in the H2020 project ECOPOTENTIAL, that developed a framework, based on the DPSIR approach, for applying the ESS concept for improving the management of Protected Areas (PA). In this study, the evaluation the impact of eutrophication on the survival of the Salmo letnica, an iconic species of the lake, is studied through a simple ecological model.

The trace-element geochemistry of speleothems is becoming increasingly used for reconstructing palaeoclimate, with a particular emphasis on elements whose concentrations vary according to hydrological conditions at the cave site (e.g. Mg, Sr, Ba and U). An important step in interpreting trace-element abundances is understanding the underlying processes of their incorporation. This includes quantifying the fractionation between the solution and speleothem carbonate via partition coefficients (where the partitioning (D) of element X (D-X) is the molar ratio [X/Ca] in the calcite divided by the molar ratio [X/Ca] in the parent water) and evaluating the degree of spatial variability across time-constant speleothem layers. Previous studies of how these elements are incorporated into speleothems have focused primarily on stalagmites and their source waters in natural cave settings, or have used synthetic solutions under cave-analogue laboratory conditions to produce similar dripstones. However, dripstones are not the only speleothem types capable of yielding useful palaeoclimate information. In this study, we investigate the incorporation of Mg, Sr, Ba and U into a subaqueous calcite speleothem (CD3) growing in a natural cave pool in Italy. Pool-water measurements extending back 15 years reveal a remarkably stable geochemical environment owing to the deep cave setting, enabling the calculation of precise solution [X/Ca]. We determine the trace element variability of 'modern' subaqueous calcite from a drill core taken through CD3 to derive D-Mg, D-Sr, D-Ba and D-U then compare these with published cave, cave-analogue and seawater-analogue studies. The D-Mg for CD3 is anomalously high (0.042 +/- 0.002) compared to previous estimates at similar temperatures (similar to 8 degrees C). The D-Sr (0.100 +/- 0.007) is similar to previously reported values, but data from this study as well as those from Tremaine and Froelich (2013) and Day and Henderson (2013) suggest that [ Na/Sr] might play an important role in Sr incorporation through the potential for Na to outcompete Sr for calcite non-lattice sites. DBa in CD3 (0.086 +/- 0.008) is similar to values derived by Day and Henderson (2013) under cave-analogue conditions, whilst DU (0.013 +/- 0.002) is almost an order of magnitude lower, possibly due to the unusually slow speleothem growth rates (

Stable water isotopes of precipitation are widely used to track processes occurring within the hydrological cycle and to understand regional atmospheric patterns that influence a specific area. Moreover, the use of the oxygen isotopic composition in continental carbonates (e.g. speleothems) is a well-established practice to reconstruct climatic variations in the recent past. In the Mediterranean basin, the continental carbonate δ18O is generally used as a proxy of paleo-precipitation since the water-calcite fractionation factor is able to compensate the δ18O-T gradient of about 0.2‰/°C typical of rainfall in this area. However, few comprehensive investigations were performed in the Western Mediterranean in order to analyze the statistical relationships between measured stable isotopes in precipitation and meteorological variables, and none of them accounted for the possible seasonality in these relationships. Understanding the degree of dependence of the rainfall isotopic signature from precipitation amount and temperature at present day is of primary importance in Tuscany (Central-Western Italy), where many performed palaeohydrological studies require a more precise and quantitative interpretation. To this end, in the present study 560 isotope monthly data (δ18O, δ2H, and deuterium excess) of precipitation collected in 11 sites through Tuscany from 1971 to 2018 were gathered in a database. A large part of dataset was extracted from GNIP database (and integrated with new data) or derived from local hydrogeological studies, whereas 83 new measurements were produced at two novel sites. Then, only sites whose monthly data covered almost one year were considered for processing, resulting in 474 precipitation samples archived along with monthly mean temperature and rainfall amount. In this framework, a LMWL for Tuscany Region was determined for the first time by applying different regression techniques. A Spearman’s rank correlation analysis was performed to summarize the strength and direction of the relationship between stable isotope signatures of precipitation and meteorological variables, both at monthly and annual timescale. The monthly correlation was also investigated on seasonal basis. Finally, the influence of local geographical effects (altitude, distance to the coast, etc.) on the isotopic signals registered at different sites was evaluated.

Arctic regions are extreme environments where ecosystems are undergoing significant changes induced by the temperature rise, that is progressing about twice faster than in the rest of the world. In the high-Arctic, the Critical Zone (CZ) has a thin above-ground component, consisting of tundra vegetation, and a highly seasonal below-ground component, with varying extension and chemical-physical characteristics. The complexity of this system makes future projections of the Arctic CZ a challenging goal. In particular, it is still unclear whether the system will turn from a carbon sink to a carbon source. On the one hand, the uptake of carbon dioxide (CO2) by vegetation is expected to increase in future years owing to the widening growing season and the shift in community composition but, on the other, increasing soil temperatures are fostering carbon release by thawing permafrost and degradation of organic matter through heterotrophic respiration in deglaciated soils. In this work, we identified the main biotic and abiotic drivers of CO2 emissions (Ecosystem Respiration, ER), and CO2 uptake (Gross Primary Production, GPP), in the Arctic tundra biome. During summer 2019 we extensively measured CO2 fluxes at the soil-vegetation-atmosphere interface, basic meteoclimatic variables and ecological descriptors at the Critical Zone Observatory of Bayelva river basin (CZO@Bayelva), Spitzbergen, in the Svalbard Archipelago (NO). Flux measurements were obtained by a portable accumulation chamber, allowing for the statistical analysis of fluxes variability at small scale. Together with flux measurements, we sampled soil temperature and humidity at the chamber base and local air temperature, pressure and humidity. In addition, the vegetation cover was obtained from digital RGB pictures of the sampled surfaces. By means of multi regression models, we related flux data to environmental parameters, vegetation cover extent and vegetation type, thus obtaining empirical data-driven models that describe the coupled dynamics of soil, vegetation, water and atmosphere that contribute to the present budgeting of the carbon cycle in the arctic CZ. This work may help in assessing the possible future evolution of high-Arctic environment under projected changes in vegetation community composition and abiotic parameters.

Arctic tundra is currently undergoing significant changes induced by the effects of a rapid temperature rise, that in the Arctic is about twice as fast as in the rest of the world. The response of the system composed by the permafrost active layer, soil and vegetation is especially relevant. In fact, it is still unclear whether the system will turn from a carbon sink to a carbon source, owing to the interplay of two opposite phenomena: the increasing time span of the growing season, favouring Net Ecosystem Production (NEP), and the increasing soil temperatures, favouring degradation of organic matter through heterotrophic respiration (HR) and then creating a positive climate feedback. In this work, we analyse soil-vegetation-atmosphere CO2 flux data of a field campaign conducted in the Bayelva river basin, Spitzbergen, in the Svalbard Archipelago (NO) during summer 2019, measured by a portable accumulation chamber. We use a “Critical Zone” perspective, considering the multiple interactions between biotic and abiotic components. We measured the Net Ecosystem Exchange (NEE) and Ecosystem Respiration (ER) along a slope gradient at different degrees of soil humidity and active layer depths, relating flux data to climate and environmental parameters, soil physical-chemical parameters and vegetation type. The statistical empirical relationships between variables are analysed to identify the main drivers of carbon exchanges. An empirical data-driven model is built to describe the coupled dynamics of soil, vegetation, water and atmosphere that contributes to budgeting the carbon cycle in the Arctic Critical Zone. A comparison of the carbon fluxes obtained with the accumulation chamber method and an Eddy Covariance tower located in the same area is also addressed.

The Massaciuccoli lake of and the ex Porta Lake have been selected as Sites of Importance of the European Community for the particular biocommunities that they host. These areas have a complex history that has seen man intervening constantly over the centuries with reclamation operations, so that the landscape we see today is the result of a natural environment strongly shaped by man. Recent studies, conducted using a sequential stratigraphic approach, show that the depositional architecture of the Versilia Plain is determined by the variation in relative sea level, the amount of sedimentary input and the erosive capacity of the main watercourses, which have led to the formation of engraved paleovalleys. By using the stratigraphies collected in the IGGDATABASE, an attempt of stratigraphic reconstruction of the subsurface has been carried out in this work, underling that multidisciplinary detailed studies are necessary to better define the recent palaeoenvironmental evolution (Pleistocene-Holocene) and the depositional architecture of the subsurface of these areas. Moreover, a detailed monitoring of these systems both for abiotic and biotic parameters is needed as essential mean for their protection and preservation.

In high mountains, the Critical Zone (CZ) is a thin layer sustaining the whole local ecosystem. Here, however, the effects of climate change are manifesting most rapidly than in the surrounding lowlands. This is especially critical for the high-altitude carbon cycle, for which our knowledge is still patchy and new feedbacks could possibly be triggered. In particular, models of the processes that control carbon fluxes in mountain grasslands and Alpine tundra need to be improved. To contribute to fill this knowledge gap, in 2017 a new Critical Zone Observatory was established at the valley of the Nivolet Plain (CZO@Nivolet) in the Gran Paradiso National Park (GPNP), in the western Italian Alps, at about 2700 m asl. Three measurement sites were identified along the flanks of the valley. The sites are characterized by soils developed over carbonate rocks, gneiss rocks and glacial deposits. Since 2017, every year, from July to October, fluxes of carbon dioxide (CO2) were measured using a portable accumulation chamber, together with basic meteo-climatic and environmental variables, such as soil and air temperature and moisture, air pressure and solar radiation. This work is focused on a novel empirical model that uses unbiased and rigorous statistical analysis of these data to identify the environmental variables that control CO2 fluxes in Alpine tundra. The modelling approach is applied to the full dataset of simultaneous in situ measurements of the net exchange, ecosystem respiration and environmental variables for the three sites and the three measurement years. Since a large year-to-year variability in the dependencies on solar irradiance and environmental temperature is observed, a multi-regressive model has been implemented, where additional variables are introduced as perturbations of the standard functions. The multi-regressive model identifies the main drivers, highlighting the crucial role of soil moisture, and largely explains the temporal variability of the fluxes, with explained variance up to 90%. This model provides a basis for estimating future scenarios of carbon fluxes in high-altitude Alpine ecosystems.

Understanding low temperature carbon sequestration through serpentinite&ndash, H2O&ndash, CO2 interaction is becoming increasingly important as it is considered a potential approach for carbon storage required to offset anthropogenic CO2 emissions. In this study, we present new insights into spontaneous CO2 mineral sequestration through the formation of hydromagnesite + kerolite with minor aragonite incrustations on serpentinite walls of the Montecastelli copper mine located in Southern Tuscany, Italy. On the basis of field, petrological, and geochemical observations coupled with geochemical modeling, we show that precipitation of the wall coating paragenesis is driven by a sequential evaporation and condensation process starting from meteoric waters which emerge from fractures into the mine walls and ceiling. A direct precipitation of the coating paragenesis is not compatible with the chemical composition of the mine water. Instead, geochemical modeling shows that its formation can be explained through evaporation of mine water and its progressive condensation onto the mine walls, where a layer of serpentinite powder was accumulated during the excavation of the mine adits. Condensed water produces a homogeneous film on the mine walls where it can interact with the serpentinite powder and become enriched in Mg, Si, and minor Ca, which are necessary for the precipitation of the observed coating paragenesis. The evaporation and condensation processes are driven by changes in the air flow inside the mine, which in turns are driven by seasonal changes of the outside temperature. The presence of &ldquo, kerolite&rdquo, a Mg-silicate, is indicative of the dissolution of Si-rich minerals, such as serpentine, through the water&ndash, powder interaction on the mine walls at low temperature (~17.0 to 18.1 &deg, C). The spontaneous carbonation of serpentine at low temperature is a peculiar feature of this occurrence, which has only rarely been observed in ultramafic outcrops exposed on the Earth&rsquo, s surface, where instead hydromagnesite predominantly forms through the dissolution of brucite. The high reactivity of serpentine observed, in this study, is most likely due to the presence of fine-grained serpentine fines in the mine walls. Further study of the peculiar conditions of underground environments hosted in Mg-rich lithologies, such as that of the Montecastelli Copper mine, can lead to a better understanding of the physical and chemical conditions necessary to enhance serpentine carbonation at ambient temperature.

We present new data on the 4.2 ka event in the central Mediterranean from Corchia Cave (Tuscany, central Italy) stalagmite CC27. The stalagmite was analyzed for stable isotopes (δ13C and δ18O) and trace elements (Mg, U, P, Y), with all proxies showing a coherent phase of reduced cave recharge between ca. 4.5 and 4.1 ka BP. Based on the current climatological data on cyclogenesis, the reduction in cave recharge is considered to be associated with the weakening of the cyclone center located in the Gulf of Genoa in response to reduced advection of air masses from the Atlantic during winter. These conditions, which closely resemble a positive North Atlantic Oscillation (NAO) type of configuration, are associated with cooler and wetter summers with reduced sea warming, which reduced the western Mediterranean evaporation during autumn–early winter, further reducing precipitation.

We present new data on the 4.2 ka BP event in the central Mediterranean from Corchia Cave (Tuscany, central Italy) stalagmite CC27. The stalagmite was analysed for stable isotopes (δ13C δ18O) and trace elements (Mg, U, P, Y), with all proxies showing a coherent phase of reduced cave recharge between ca. 4.5 and 4.1 ka. Based on the current climatological data on cyclogenesis, the reduction in cave recharge is considered associated to weakening of the cyclone centre located in the Gulf of Genoa in response to reduced advection of air masses from Atlantic during winter. These conditions, which closely resemble a positive North Atlantic Oscillation (NAO)-like configuration, are associated with cooler and wetter summers, with reduced sea warming, which reduced the western Mediterranean evaporation during autumn-early winter further reducing precipitation.

The alluvial plain of the Ceyhan River (SE Turkey) has been populated since the Neolithic. In 1954, Marjory Veronica Seton-Williams described for this area several archeological mounds (höyük), which are the remains of ancient settlements. Today, according to the archeological research carried out in the area, some of these mounds result to have been leveled by agricultural activities. In this work, we identified many color anomalies by low-cost remote-sensing analyses of satellite images. We checked the nature of these anomalies in a dedicated survey and we found a good correspondence between color anomalies and archeological remains consistent with leveled höyük. We compared the grain size and chemical characteristics of the soil collected inside the color anomalies with the soil collected in other areas of the alluvial plain. We found irrelevant differences in grain-size characteristics, but a higher content of CaCO3 in soils collected inside the anomalies with respect to those collected outside. Therefore, the content of CaCO3 could be considered the feature that makes the color anomalies visible. The reason for this higher content of CaCO3 is related to the anthropogenic material used in the different phases of höyük growth. This work suggests a low-cost analysis useful for rapid identification and preservation of archeological information on the history of Mediterranean settlement.

© 2018 Elsevier Ltd In the DEEP core from the Lake Ohrid ICDP drilling project, the carbon isotope composition of bulk organic matter (δ 13 C TOC ) over the last 516 ka shows a negative correlation with total organic carbon (TOC) and total inorganic carbon (TIC). This relationship is marked by periods of lower δ 13 C TOC values corresponding to higher TIC and TOC. Along with TOC/TN, the correlation between δ 13 C TOC and δ 13 C TIC suggests that most of the organic matter in the core is from aquatic primary production within the lake. The combination of TOC, TIC, and δ 13 C TOC is able to disentangle long-term glacial/interglacial cycles and, to a lesser extent, millennial scale climate variability. Over the longer term, δ 13 C TOC shows modest variability, indicating that the δ 13 C of the dissolved inorganic carbon (DIC) pool is stabilised by the supply of karst spring water characterised by δ 13 C DIC influenced by the bedrock δ 13 C value, and the long residence time of the lake water and well mixed upper water column promoting equilibration with atmospheric CO 2 . However, comparison between arboreal pollen (AP%), TIC and TOC data indicates that the δ 13 C TOC signal is modulated by the leaching of soil CO 2 through runoff and spring discharge, changes in primary productivity, and recycling of organic matter within the lake, all affecting δ 13 C DIC . Exceptionally low δ 13 C TOC during some interglacial periods (e.g. MIS7 and MIS9) possibly indicate rapid intensification of organic matter recycling and/or increasing stratification and enhanced methanogenesis, even if the latter process is not supported by the sedimentological data.

In 2017 we established the first Earth Critical Zone Observatory in Italy, at the high-altitude Nivolet plain in the Gran Paradiso National Park, between about 2500 and 2700 meters asl (CZO@Nivolet). The Observatory is currently equipped with an eddy-covariance tower for CO2 and H2O fluxes; a portable accumulation chamber to measure H2O, CO2, CH4 and H2S fluxes; a double rain gauge for rainfall isotopic studies; soil moisture and hydrometric gauges. Regular samplings of the physical and chemical properties of soil as well as surface and groundwater are performed. The in-situ instruments are complemented by analyses in a suite of geochemical and isotopic laboratories at CNR IGG in Pisa and by analysis of high-resolution satellite images. While the CZO@Nivolet has multiple goals and the instrument pool is continuously upgraded, a specific question we have considered during the first year of activity is whether and how the geological setting and the geological substratum of soils affect carbon fluxes in a mountain prairie above the tree line. To this end, we have identified four plots, each having an average area of about 200 square meters, characterized by different geological substratum: (1) soil on gneiss (the dominant rock type of the Gran Paradiso massif), (2) soil on carbonate rocks, (3) soil over glacial deposits (common to most alpine areas), and (4) alluvial soil near the main stream of the Nivolet plain (Dora del Nivolet). In each plot, we performed on average 30 randomly-positioned flux measurements with the accumulation chamber method, approximately every two weeks from June to October 2017 and measuring both the sum of photosynthesis and respiration (using a transparent chamber) and pure respiration (using an opaque chamber). The preliminary results of the statistical analyses indicate that the carbonate soils behave quite differently from the other three types. A full discussion of the findings and their implications will be given.

Diplomazia2 is framed within the program "Science for Diplomacy: Multi-disciplinary Training Program", and it is the result of closer and more mature collaboration between the Directorate General for Cooperation on Development of the Ministry for Foreign Affairs and International Cooperation (MAECI), the Italian Agency for Cooperation on Development (AICS) and the National Research Council (CNR). The implementation of joint projects such as DIPLOMAzia2 highlights the effectiveness of the diplomacy-science partnership as the driving force behind the achievement of relevant goals jointly pursued by the international community.

Here we present stable isotope and geochemical data from Lake Prespa (Macedonia/Albania border) over the Last Glacial cycle (Marine Isotope Stages 5–1) and discuss past lake hydrology and climate (TIC, oxygen and carbon isotopes), as well as responses to climate of terrestrial and aquatic vegetation (TOC, Rock Eval pyrolysis, carbon isotopes, pollen). The Lake Prespa sediments broadly fall into 5 zones based on their sedimentology, geochemistry, palynology and the existing chronology. The Glacial sediments suggest low supply of carbon to the lake, but high summer productivity; intermittent siderite layers suggest that although the lake was likely to have mixed regularly leading to enhanced oxidation of organic matter, there must have been within sediment reducing conditions and methanogenesis. MIS 5 and 1 sediments suggest much more productivity, higher rates of organic material preservation possibly due to more limited mixing with longer periods of oxygen-depleted bottom waters. We also calculated lakewater δ18O from siderite (authigenic/Glacial) and calcite (endogenic/Holocene) and show much lower lakewater δ18O values in the Glacial when compared to the Holocene, suggesting the lake was less evaporative in the Glacial, probably as a consequence of cooler summers and longer winter ice cover. In the Holocene the oxygen isotope data suggests general humidity, with just 2 marked arid phases, features observed in other Eastern and Central Mediterranean lakes.

A multi-proxy record is presented for approximately the last 4500 cal a BP from Lake Shkodra, Albania/ Montenegro. Lithological analyses, C/N ratio and d 13 C of the organic and inorganic carbon component suggest that organic matter and bulk carbonate are predominantly authigenic. The d 18 O record of bulk carbonate indicates the presence of two prominent wet periods: one at ca. 4300 cal a BP and one at ca. 2500-2000 cal a BP. The latter phase is also found in southern Spain and Central Italy, and represents a prominent event in the western and central Mediterranean. In the last 2000 years, four relatively wet intervals occurred between ca. 1800 and 1500 cal a BP (150-450 AD), 1350-1250 (600-700 AD), 1100-800 (850-1150 AD), and at ca. 90 cal a BP (1860 AD). Between ca. 4100 and 2500 cal a BP d 18 O values are relatively high, with three prominent peaks indicating drier conditions at ca. 4100-4000 cal a BP, ca. 3500 and at ca. 3300 cal a BP. Four additional drier events are identified at 1850 (ca. 100 AD), 1400 (ca. 550 AD), 1150 (800 AD) and ca.750 cal a BP (1200 AD). The pollen record does not show changes in accordance with these episodes owing to the poor sensitivity of vegetation in this area, which is dominated by an orographic rainfall effect and where changes in altitudinal vegetation belts do not affect the pollen rain in the lake catchment. However, since ca. 900 cal a BP a significant decrease in the percentage arboreal pollen and in pollen concentrations suggest major deforestation produced by human activities. Copyright # 2012 John Wiley & Sons, Ltd.

Excavations at Arslantepe have brought to light a lot of archaeobotanical material dating from 5300 to 3950 years BP. The archaeobotanical studies highlighted the presence of various botanical taxa preserved by charring. The great diversity in founding taxa and the selective use of wood can be either due to a choice or selection or even to an environmental availability. Stable carbon isotope analysis was carried out to disentangle the human choice and climate variation. In fact, δ13C values of both fresh and charred wood are environmental proxies and are related to drought stress.Analysis of selected fossil woods (deciduous Quercus and Juniperus sp.) and caryopsis (Triticum dicoccon and Hordeum vulgare) from the archaeological site were carried out. Fresh plant parts (leaf and branches) of the same taxa have been sampled in the Arslantepe area.A lot of studies correlated cultural changes with environmental factors. At Arslantepe a number of important changes are found. It is not clear, however, if the significant variations found in plants use by the successive settlers are due to cultural choices or to environmental changes. Independent information on environmental variation obtained using isotope analysis, will help archaeobotanical studies to discriminate cultural and environmental changes.

The Holocene evolution of the Cabo Raso bay (Atlantic Patagonian coast) was reconstructed by means of geomorphological, stratigraphic, and palaeontological analyses, assisted by radiocarbon dating. Six beach ridges were individuated and mapped in the field, as well as some rocky erosional landforms,e.g.,inner margins of marine terraces. Thanks to quarry sections, the internal structure of beach ridges, their relationship with continental deposits, and the fossil contents were determined. Two specimens ofAulacomya atraandBrachidontes purpuratuswere radiocarbon dated at 6055 and 4500 ± 20 YBP, respectively. The bedrock outcrops at the base of an analysed section allowed us to associate the age of the samples collected to the elevation of the marine transgression surface upon which the entire deposit rests. Because a beach ridge is a regressive form, the elevation of the base of the dated deposit was assumed to be equivalent to or slightly lower than the maximum sea-level stationing, represented by the inner margin of the coheval marine terrace. The altimetric correlation between the base of the beach ridge dated at 6055 ± 20 YBP and the inner margin of the corresponding marine terraces allowed us to constrain the maximum Holocene marine transgression to about 3 to 2m above sea level. This elevation for the maximum Holocene transgression is lower than that shown by most of the previous data for Patagonian coast, but it shows a crude agreement with recent estimates coming from geophysical models that report, for this area, a departure from the eustatic value of sea level, mainly caused by glacioisostatic process. This means that the employment of marine erosional landforms, associated with other multisource field data, proved to be determinant for reconstructing the sea-level variation in the Patagonian coast.

In Near Eastern archaeology, studies on crop management during the early stages of civilisation have been based on cuneiform texts and only recently have geoarchaeological surveys and archaeobotanical studies tried to identify agricultural practices. Nevertheless, direct evidence for irrigation and water management is very rare and difficult to interpret. New possibilities for analysing these ways of management have been provided by stable carbon isotope analysis of ancient crops. In this study carbon isotope discrimination (Delta C-13) was performed to assess the growing conditions of fossil cereal grains. Charred grains of emmer and barley recovered from the same site, Arslantepe in eastern Anatolia, over a 1,000 years long continuous sequence during the third millennium b.c. have been analysed and compared. The variation in water availability during grain filling, estimated by Delta C-13, can be attributed to climate change and/or human practices. Distinguishing exactly which is to blame is complex but essential in reconstructing specific management practices. Variations in the C-13/C-12 ratio suggest that barley and emmer grew under different water regimes. In particular, a different management system was adopted between 3000 and 2800 cal. b.c. when emmer was sustained by human-induced water supply, whereas the more resistant barley was rain-fed and possibly assigned to more marginal terrains. Our results are compared with the stable carbon isotope data available for other Near Eastern sites. Emmer and barley records are also compared with deciduous oak Delta C-13 from Arslantepe in order to better understand the influence of environmental factors, climate and human impact.

The C-13/C-12 ratio of juniper charcoals from the archaeological site of Arslantepe, Malatya (Turkey) was analysed for the mid-Holocene period spanning from 3350 to 2000 years BC. In addition, modern juniper and deciduous oak specimens were collected during a botanical survey around Arslantepe in August 2008. After the evaluation of weather parameters, the modern C-13/C-12 ratio was compared with the archaeological one, to infer past seasonal precipitation relative magnitude patterns. Delta C-13 values obtained from these samples suggest that the present-day climate is, on average, drier than that recorded in the past. Comparing the Delta C-13 juniper record with the already published curve for archaeological charcoals of deciduous oaks from Arslantepe, it appears that the two curves show similar trends in the short period between ca. 2850 and 2500 BC, in which the curves are substantially parallel and the Delta C-13 difference between them is quite reduced, but they are shifted by ca. 50-150 years in the rest of the record. For the interpretation of the arboreal curves, however, it was necessary to consider the autoecology of modern plants and the source of the water used for photosynthesis, as the two selected trees show Delta C-13 curves with rather different patterns. Overall, C-13/C-12 contrasting ratios in juniper and deciduous oaks suggest that seasonality in rainfall distribution and aquifer recharge played a complex role. Thus, a consistent seasonal contrast in precipitation (similar to the one in recent times) took place at ca. 3350, 3100, and 2300 BC indicating that semi-arid conditions have occurred in the past, in alternation with periods characterised by minor differences in the distribution of annual precipitation. In particular, the period between ca. 2850 and 2500 BC may suggest more humid conditions in late winter/early spring. The combination of the two records suggests that 1) two periods of drought are found at ca. 3350-3100 and at ca. 2300-2200 BC and 2) that at present winter precipitation is lower than that recorded during the period 3350-2000 BC and summer aridity less or equal to that recorded ca. 2200 BC. Changes in precipitation seasonality and the complex and the peculiar hydrogeological situation hindered the interpretation of the isotope records. The use of two taxa having different autoecology and different growing season allows interpretation of the data in terms of changes in precipitation seasonality and of specific habitat in this complex and peculiar hydrological setting.

Obtaining meaningful redox potential determinations is questionable in disequilibrium solutions, like surface waters and groundwater. However, identifying redox processes in a natural ecosystem is a key factor to characterize the chemical quality and, consequently, the sustainability of that environment. To do that, the determination of an exact redox potential is not needed and on many cases it is more important to describe how and if the redox state of a system changes. In particular, the redox status of aqueous systems is assigned based on analysis of samples for redox-sensitive compounds. In general, these analyses do not include measurements of gases dissolved in the waters. Here, we present an innovative method to underline in an easy way changes in redox state of a system using the elemental composition (C, H, S) measured in the headspace gas after the equilibration with water phase. The results allow defining the empirical formula of the gas, the mean number of oxidation of the carbon and the molar ratio between C:H:S. The method is applied to investigate the redox condition in a stratified lake, San Rocchino (Northern Tuscany, Italy) using an instrument (Thermo Scientific FlashEA 1112) equipped for headspace gas analysis. Samples of waters and dissolved gases were collected at five different depths along a vertical profile. Such analytical system is used to determine the mean oxidation number of the carbon gaseous phase in the headspace, which allows distinguishing relatively oxidizing from relatively reducing condition. Further information on the redox state is reached considering the molar ratio C/H and C/S. This innovative method is simple and rapid, and the instrument is robust and it needs low maintenance. Moreover, it could be applied to other research and exploratory fields, such as geothermic and volcanic monitoring, polluted aquifer and contaminated sites.

This paper investigates the stable isotopic composition from late Pleistocene–Holocene (~ 13 to ~ 10.5 cal ka BP) shells of the land snail Helix figulina, from Franchthi Cave (Greece). It explores the palaeoclimatic and palaeoenvironmental implications of the isotope palaeoecology of archaeological shells at the time of human occupation of the cave. Modern shells from around the cave were also analysed and their isotopic signatures compared with those of the archaeological shells. The carbon isotope composition of modern shells depicts the consumption of C3 vegetation. Shell oxygen isotopic values are consistent with other Mediterranean snail shells from coastal areas. Combining empirical linear regression and an evaporative model, the δ18Os suggest that modern snails in the study area are active during periods of higher relative humidity and lower rainfall δ18O, probably at night. Late glacial and early Holocene δ18Os show lower values compared to modern ones. Early Holocene δ18Os values likely track enhanced moisture and isotopic changes in the precipitation source. By contrast, lower late glacial δ18O could reflect lower temperatures and δ18Op, compared to the present day. Shell carbon isotope values indicate the presence of C3 vegetation as main source of carbon to late glacial and early Holocene snails.