• Energy Research

Cities are responsible for more than 80% of global greenhouse gas emissions. Sequestration of air pollutants is one of the main ecosystem services that urban forests provide to the citizens. The atmospheric concentration of several pollutants such as carbon dioxide (CO2), tropospheric ozone (O3), and particulate matter (PM) can be reduced by urban trees through processes of adsorption and deposition. We predict the quantity of CO2, O3, and PM removed by urban tree species with the multilayer canopy model AIRTREE in two representative urban parks in Italy: Park of Castel di Guido, a 3673 ha reforested area located northwest of Rome, and Park of Valentino, a 42 ha urban park in downtown Turin. We estimated a total annual removal of 1005 and 500 kg of carbon per hectare, 8.1 and 1.42 kg of ozone per hectare, and 8.4 and 8 kg of PM10 per hectare. We highlighted differences in pollutant sequestration between urban areas and between species, shedding light on the importance to perform extensive in situ measurements and modeling analysis of tree characteristics to provide realistic estimates of urban parks to deliver ecosystem services.

AbstractRising ozone (O3) concentrations, coupled with an increase in drought frequency due to climate change, pose a threat to plant growth and productivity which could negatively affect carbon sequestration capacity of Northern Hemisphere (NH) forests. Using long‐term observations of O3 mixing ratios and soil water content (SWC), we implemented empirical drought and O3 stress parameterizations in a coupled stomatal conductance–photosynthesis model to assess their impacts on plant gas exchange at three FLUXNET sites: Castelporziano, Blodgett and Hyytiälä. Model performance was evaluated by comparing model estimates of gross primary productivity (GPP) and latent heat fluxes (LE) against present‐day observations. CMIP5 GCM model output data were then used to investigate the potential impact of the two stressors on forests by the middle (2041–2050) and end (2091–2100) of the 21st century. We found drought stress was the more significant as it reduced model overestimation of GPP and LE by ~11%–25% compared to 1%–11% from O3 stress. However, the best model fit to observations at all the study sites was obtained with O3 and drought stress combined, such that the two stressors counteract the impact of each other. With the inclusion of drought and O3 stress, GPP at CPZ, BLO and HYY is projected to increase by 7%, 5% and 8%, respectively, by mid‐century and by 14%, 11% and 14% by 2091–2100 as atmospheric CO2 increases. Estimates were up to 21% and 4% higher when drought and O3 stress were neglected respectively. Drought stress will have a substantial impact on plant gas exchange and productivity, off‐setting and possibly negating CO2 fertilization gains in future, suggesting projected increases in the frequency and severity of droughts in the NH will play a significant role in forest productivity and carbon budgets in future.

Negative environmental changes generally addressed as ‘syndromes’ areevaluated in the context of Soil Degradation (SD) and interpreted by usinga ‘Land-Use/Land Cover Changes’ (LULCCs) framework in order to dis-entangle ‘past trajectories’, ‘present patterns’, and ‘future changes’. Thisapproach allows to discuss the potential impact on SD processes and itrepresents an informed basis for identifying measurable outcomes of SD.This study focuses on the case of Emilia Romagna, a region located inthe North of Italy with high-value added agricultural productions. A multi-temporal analysis of land-use changes between 1954 and 2008 has been proposed, discussing the evolution of associated SD syndromes in EmiliaRomagna. The contributing information have been used as a baseline forSustainable Land Management (SLM) strategies. This framework of analysisprovides useful tools to investigate and to monitor the effects of SD in theMediterranean basin where several regions underwent common developmentpatterns yelding global pathological symptoms of environmental degradation.

This is the 2024-1 release of the ICOS final quality ecosystem data product that includes eddy covariance fluxes, meteorological observations, ancillary and biometric data and full metadata at 73 labelled ICOS stations in the ecosystem domain. The archives contain more detailed description of the different data files contained in the archives. Measurements have been collected using the following instructions: ICOS Ecosystem Instructions for Air Meteorological Measurements (TA, RH, PA, WS, WD), https://doi.org/10.18160/NHEG-4KWW ICOS Ecosystem Instructions for Turbulent Flux Measurements of CO2, Energy and Momentum, https://doi.org/10.18160/QWV4-639G

AbstractFundamental axes of variation in plant traits result from trade-offs between costs and benefits of resource-use strategies at the leaf scale. However, it is unclear whether similar trade-offs propagate to the ecosystem level. Here, we test whether trait correlation patterns predicted by three well-known leaf- and plant-level coordination theories – the leaf economics spectrum, the global spectrum of plant form and function, and the least-cost hypothesis – are also observed between community mean traits and ecosystem processes. We combined ecosystem functional properties from FLUXNET sites, vegetation properties, and community mean plant traits into three corresponding principal component analyses. We find that the leaf economics spectrum (90 sites), the global spectrum of plant form and function (89 sites), and the least-cost hypothesis (82 sites) all propagate at the ecosystem level. However, we also find evidence of additional scale-emergent properties. Evaluating the coordination of ecosystem functional properties may aid the development of more realistic global dynamic vegetation models with critical empirical data, reducing the uncertainty of climate change projections.

This is the 2023-2 INTERIM release of the ICOS final quality ecosystem data product that includes eddy covariance fluxes, meteorological observations, ancillary and biometric data and full metadata at 39 labelled ICOS stations in the ecosystem domain. The archives contain more detailed description of the different data files contained in the archives. Please note that the 2023 measurements included in this interim release don't cover the full year, but do essentially cover the growing season. Measurements have been collected using the following instructions: ICOS Ecosystem Instructions for Air Meteorological Measurements (TA, RH, PA, WS, WD), https://doi.org/10.18160/NHEG-4KWW ICOS Ecosystem Instructions for Turbulent Flux Measurements of CO2, Energy and Momentum, https://doi.org/10.18160/QWV4-639G