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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 (

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.

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.

Within the H2020 ECOPOTENTIAL project, started in 2015, a framework has been developed for applying the ESS concept for improving the management of Protected Areas (PA). Based on the DPSIR approach, storylines have been developed for the most relevant ecosystems in each PA, identifying the critical ecosystem processes, their control factors, threats, drivers/pressures, the state of the environment and the responses, thus contextualizing the workflow of ECOPOTENTIAL in particular ecological, management and policy settings. In the context of the project, Earth Observation data, including in–situ and Remote Sensing (RS) necessary for building an appropriate set of indicators have been identified. One of the targeted PA in ECOPOTENTIAL is the region of Lakes Orhid and Prespa, which extends across Greece, Albania and the FYRof Macedonia, the latter ones aiming to join the European Union. Both lakes are of outmost importance because of their unique geological and ecological characteristics. Lake Orhid, in particular, 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 ESS, as sustainable tourism, food production and supply of freshwater. Nevertheless, the importance of preserving the ecosystem has never been evaluated before using the ESS approach, while non-market approaches useful for assessing the value of ESS have been identified (Zdraveski et al., 2015). In this presentation, we describe the ECOPOTENTIAL approach for evaluating the link between the biophysical characteristics of the lake and the provision of ESS, illustrating it on selected ESS, and how this tool, based on a causal mapping of the inter-correlations among in situ and RS data, indicators, determinants and ESS, can be a valuable instrument for informing the decision makers for better management of the lake and the preservation of its unique biodiversity and ecosystem services.

The alpine grassland of Gran Paradiso National Park (Italy) resulted from centuries of human activities that created high biodiversity semi-natural areas below the timberline. The progressive abandonment of management practices as well as climate change lead to variations in species diversity. In order to apply active management actions for maintaining such ecosystem a long-term monitoring programme started in 2016. We will present the first results of spatial and temporal variability of CO2 fluxes from grasslands in relation to meteo-climatic conditions, together with soil properties.

Within the H2020 ECOPOTENTIAL project, started in 2015, a framework has been developed for applying the ESS concept for improving the management of Protected Areas (PA). Based on the DPSIR approach, storylines have been developed for the most relevant ecosystems in each PA, identifying the critical ecosystem processes, their control factors, threats, drivers/pressures, the state of the environment and the responses, thus contextualizing the workflow of ECOPOTENTIAL in particular ecological, management and policy settings. In the context of the project, Earth Observation data, including in���situ and Remote Sensing (RS) necessary for building an appropriate set of indicators have been identified. One of the targeted PA in ECOPOTENTIAL is the region of Lakes Orhid and Prespa, which extends across Greece, Albania and the FYRof Macedonia, the latter ones aiming to join the European Union. Both lakes are of outmost importance because of their unique geological and ecological characteristics. Lake Orhid, in particular, 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 ESS, as sustainable tourism, food production and supply of freshwater. Nevertheless, the importance of preserving the ecosystem has never been evaluated before using the ESS approach, while non-market approaches useful for assessing the value of ESS have been identified (Zdraveski et al., 2015). In this presentation, we describe the ECOPOTENTIAL approach for evaluating the link between the biophysical characteristics of the lake and the provision of ESS, illustrating it on selected ESS, and how this tool, based on a causal mapping of the inter-correlations among in situ and RS data, indicators, determinants and ESS, can be a valuable instrument for informing the decision makers for better management of the lake and the preservation of its unique biodiversity and ecosystem services.

This poster has been presented at the First ILTER Open Science Meeting in Skukuza, South Africa, in October 2016. It describes the set up of a new Long term experiment on the abandonment of Alpine Grasslands The open areas of Gran Paradiso National Park (GPNP), in the western Italian Alps, are the result of centuries of human activities that determined a lowering of the treeline ecotone, creating peculiar seminatural areas below the timberline, characterised by high biodiversity values. The progressive abandonment of management practices as well as climate change lead to variations in species diversity with respect to extensively used meadows, with fragmentation of semi-natural grassland due to increase of forests and woodlands. GPNP would like to apply active management actions for maintaining such semi-natural grassland and their high biodiversity. In particular, a long-term monitoring programme started in 2016 in selected sites of GPNP aimed to: 1) evaluate the effects of a well managed grazing system on animal and plant biodiversity; 2) compare the evolution of managed and non-managed areas, the latter obtained by excluding a portion of the meadows from grazing. Monitoring includes plant community, invertebrates, soil properties and CO2 fluxes, related also to meteo-climatic conditions. Measures are planned to continue in the next 10 years at least.

This pre-print paper illustrate experimental work and the data analysisconducted in Gran Paradiso National Park, Italy, by researchers of the Institute of Geoscience and Earth Resources of The National Research Council of Italy in the framework of the H2020 project ECOPOTENTIAL (www.ecopotential-project.eu), regarding the CO2 fluxes on high- altitude Alpine grasslands at Nivolet Plain (about 2700 m a.s.l.). Measurements of Net Ecosystem Exchange (NEE) and Ecosystem Respiration (ER) and other environmental variables have been conducted in three sampling sites belonging to the same catchment during 2017, 2018, 2019 summer seasons, using a portable accumulation chamber. In the paper,we propose a comparison of three empirical modelling approaches using systematic statistical analysis, to identify the environmental variables controlling CO2 fluxes. Large year-to-year variations in the gross primary production (GPP) and ecosystem respiration (ER) dependences on solar irradiance and temperature were observed,. We thus implemented a multi regression model in which additional variables were introduced as perturbations of the standard exponential and rectangular hyperbolic functions for ER and GPP, respectively. A comparison of this model with other common modelling strategies, showed the benefits of this approach, resulting in large explained variances (83% to 94%). The optimum ensemble of variables explaining the inter- and intra-annual flux variability included solar irradiance, soil moisture and day of the year for GPP, and air temperature, soil moisture, air pressure and day of the year for the ER, in agreement with other studies. The modelling approach discussed provides a basis for selecting drivers of carbon fluxes and understanding their role in high-altitude Alpine ecosystems, also allowing for future short-range assessments of local trends

This poster has been presented at the First ILTER Open Science Meeting in Skukuza, South Africa, in October 2016. It describes the set up of a new Long term experiment on the abandonment of Alpine Grasslands The open areas of Gran Paradiso National Park (GPNP), in the western Italian Alps, are the result of centuries of human activities that determined a lowering of the treeline ecotone, creating peculiar seminatural areas below the timberline, characterised by high biodiversity values. The progressive abandonment of management practices as well as climate change lead to variations in species diversity with respect to extensively used meadows, with fragmentation of semi-natural grassland due to increase of forests and woodlands. GPNP would like to apply active management actions for maintaining such semi-natural grassland and their high biodiversity. In particular, a long-term monitoring programme started in 2016 in selected sites of GPNP aimed to: 1) evaluate the effects of a well managed grazing system on animal and plant biodiversity; 2) compare the evolution of managed and non-managed areas, the latter obtained by excluding a portion of the meadows from grazing. Monitoring includes plant community, invertebrates, soil properties and CO2 fluxes, related also to meteo-climatic conditions. Measures are planned to continue in the next 10 years at least.

The alpine grassland of Gran Paradiso National Park (Italy) resulted from centuries of human activities that created high biodiversity semi-natural areas below the timberline. The progressive abandonment of management practices as well as climate change lead to variations in species diversity. In order to apply active management actions for maintaining such ecosystem a long-term monitoring programme started in 2016. We will present the first results of spatial and temporal variability of CO2 fluxes from grasslands in relation to meteo-climatic conditions, together with soil properties.