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ON 16 NOVEMBER 2000, the final report of the World Commission on Dams (WCD) was launched in London, in the presence of South Africa’s former president Nelson Mandela. This represented a remarkable milestone in the history of dam policy and politics. During its two-year existence, WCD had conducted the most extensive review of research and evidence regarding the planning, impacts, and management of large dams. It had engaged with numerous stakeholders around the globe. It also made comprehensive recommendations about how to improve dam planning and management.

The Joint Research Center (JRC) has set a series of thresholds to define marginal lands in terms of biophysical constraints. We focus on climate limitation given by the ratio between precipitations and potential evapotranspiration (P/PET). Indeed, the Mediterranean climates are characterized by long drought periods during summer, with low rainfall and high evapotranspiration, what limits plant CO2 assimilation and biomass production, particularly of spring-summer crops. The present study ascertained the potential and actual yield of African fodder cane (Saccharum spontaneum ssp. aegypticum), a perennial, herbaceous, rhizomatous perennial grass, native from North Africa and widespread in South Mediterranean regions. Saccharum was grown under different water regimes (I0 - rainfed, I50 – 50% ETm and I100 – 100% ETm restoration) for six successive growing seasons, namely from the 7th to the 12th. Throughout the experimental period, the dryness index greatly changed among the six growing seasons: three out of the six (2012, 2013 and 2014) were much lower than the threshold of 0.6 set in the JRC report, indicating severe drought seasons, two were quite similar to the threshold value (2015 and 2016), while the 2011, which was the wettest season overall, had a dryness index higher than the threshold. Actual biomass yield was mostly driven by meteorological conditions through the growing seasons. However, even in the driest seasons, Saccharum was able to maintain satisfactory biomass yield and good yield persistence. As compared to the potential yield (I100), the relative yield reduction over the six years was in the range of 31% in the most stress condition (I0), but the energy productivity and the water footprint improved by 62% and 32%, respectively, indicating a higher sustainability of the cropping system when irrigation water was not provided. When the irrigation level was raised to the 50% of the maximum evapotranspiration restoration (ETm), the relative yield, over the six growing seasons, reduced by 16.5%; the energy productivity and the water footprint improved of only 14 and 22%, respectively. This study underlines the importance for strategic selection of crops for a given environmental condition dominated by a specific biophysical constraint and the agronomic practices leading to increase the energy productivity while reducing the pressure on Mediterranean freshwater. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 34-40

The internal combustion engines (ICEs) are still playing a dominant role in the powertrain vehicles although they are the main source of particle emissions in the urban area. Particle emissions are typically associated to Diesel engine, anyway direct injection spark ignition (DISI) engines play a relevant role in particle emissions because of the less time for fuel evaporation and mixing and because of the fuel impingement. The use of the oxygenated biofuels allows reducing the particle emissions. For the SI engines ethanol is the most used alternative fuel because of the higher octane number and the higher heat of vaporization compared to gasoline. Anyway, typically emit a larger number of particles smaller than 100 nm. Several studies have pointed out that health effect on human health is strongly related to particle number and size. For this reason, a particle number (PN) emission limit of 6 × 1011 #/km from Diesel and DISI engines was introduced. Anyway, only particles larger than 23 nm were taken in to account. Several researches evidenced a large presence of particles smaller than 23 nm from both Diesel and SI engines. The emissions of sub-23 nm particles can be more harmful to human health than bigger particles as they have higher deposition efficiency in the respiratory system and can translocate to other areas such as the brain. Their nature is not fully clear and their measure can be biased by the sampling conditions. The necessity to better understand the nature of sub-23 nm particles to define a proper procedure to measure them leads to the promotion of several European projects that aims to characterize particle nature as well as to develop instruments that can measure particle smaller than 23 nm. In order to properly define a measurement procedure for particle number emissions of the internal combustion engines it has to be better characterize the effect of the sampling parameters on the sub-23 nm particles. This paper aims to understand the sub-23 nm particle nature by means of the analysis of the effect of the temperature of sampling. The investigation was performed on small displacement SI DI/PFI engines fueled with gasoline, ethanol and a blend of 25%v/v of ethanol in gasoline. The tests were carried out at full load and 2000 and 4000 rpm representative of the European homologation urban driving cycle. Particle emissions were measured by means of a smokemeter, to measure the particle concentration at raw exhaust, and an Engine Exhaust Particle Sizer (EEPS), for the measurement of number and size in the range from 5.6 to 560 nm. The tests were carried out at two sampling conditions, Cold and Hot in order to estimate the presence of Volatile Organic Fraction (VOF). The results evidenced that the presence of sub-23 nm particle and of the VOF are strongly dependent on fuel and engine conditions. For each fuel the sampling conditions play a governing role on the measurement of the sub-23nm particles highlighting the necessity to a definition of a proper measurement protocol for their measure

The perspective of climate change requires an analysis of the adaptation possibilities of species currently cultivated. A powerful tool for adaptation is the relevant intra-specific biodiversity of crops. The knowledge, for different cultivars, of the responses to environmental conditions (e.g. yield response functions to water regime) can be a tool to identify options for adaptation to future climate. Models of crop response to environmental forcing might be used for this purpose, but this approach is severely constrained by the scarce knowledge on variety-specific values of model parameters, thus limiting the evaluation of intra-specific biodiversity towards adaptation. We have developed an approach towards this objective that relies on two complementary elements. A database on climatic requirements of durum wheat varieties: the yield response functions to water availability were determined from scientific literature. These functions were applied to describe the behaviour of the cultivars with respect to the soil water availability; the simulations performed by the agro-hydrological model SWAP (soil-water-plant and atmosphere), to describe the future soil water regime at landscape scale. The case-study presented here shows how the yield response of durum wheat cultivars to soil water availability can be defined by means of variety-specific threshold values of evapotranspiration deficit. The soil water regime calculated by the model is compared with the threshold values to identify varieties compatible with expected climate. The operation is repeated for a set of realizations of each climate scenario. This analysis is performed for three soils. The selected study area is a hilly region of about 40,000 ha in Southern Italy (Fortore Beneventano, Campania Region). Future climate scenarios in the area were generated within the Italian National Project AGROSCENARI. Climate scenarios at low spatial resolution generated with general circulation models (AOGCM) were downscaled by means of a statistical model. The downscaled climate scenario includes 50 realizations of daily minimum, maximum temperature and precipitation data, on a regular grid with a spatial resolution of 35 km, for the 2021-2050 period. The downscaled climate scenario was further refined by using the hydrological model which describes the soil water regime in three soils. Soil water content and evapotranspiration deficit was determined for the 50 realizations of the daily time series, taking into account the three soils, and was compared with threshold values to evaluate cultivar' adaptability to the predicted future climate. The case study shows how, in the future climate scenario, the intra-specific variability will allow to maintain the current crop production system.

This thesis is organized into three main sections, and is concerned with the design and synthesis of novel ionic liquids (ILs), and their associated electrochemical applications. In the first section, a general introduction to the field of ionic liquids is presented, followed by the synthesis and characterization details of all novel compounds used in the study. The second section summarizes work done on the development of more stable dye-sensitized solar cells (DSCs). An introduction to the field of photovoltaics and DSCs is first delivered in Chapter 3, which is followed by two chapters of original work on ionic liqiud-based electrolytes for DSC applications. In Chapter 4, it is shown that novel triazolium-based ionic liquids can be used to fabricate dye-sensitized solar cells, giving power conversion efficiencies of up to 6.00 %. The ionic liquid-based electrolytes are found to be compatible with a range of organic and inorganic photosensitizers, although the ruthenium-based dye (coded C106) exhibits the best performance. A device employing one of these newly-developed electrolytes is also shown to be very stable, retaining ca. 90% of its initial performance even after 1000 hours of continuous full sun illumination at 60 â ŠC. In Chapter 5, we focus on the development of stable porphyrin-sensitized solar cells, using IL-based electrolytes. Our studies reveal that the long-term stability of porphyrin-based DSCs are highly dependent on additives in the electrolyte. In particular, it is found that the additive, guanidinium thiocyanate, is essential for the preparation of long-lived devices. It is also shown that the beneficial effect of this additive originates from the thiocyanate anion, rather than the guanidinium cation. The third section of this thesis deals with the ionic liquid-catalyzed electroï¿Œchemical reduction of carbon dioxide. Following a general introduction on carbon dioxide mitigation using ionic liquids (Chapter 6), the results of our work in this area are presented in Chapter 7. Our studies reveal that not all ionic liquids are stable at the potentials required for CO2 reduction. However, the imidazolium-based salts generally perform quite well. The catalytic effect of the IL is found to mainly stem from the cation, with the anion playing a somewhat secondary role. Our results also demonstrate that substitutions on the imidazolium ring can have a huge impact on catalysis. Product analysis shows that the best-performing catalyst produces carbon monoxide as the dominant product, with Faradaic efficiencies of between 70 to 80 %.

The three different future scenarios showed an increase in mean temperature for all months between 0.5-2.4°C and a reduction in precipitation (by 4-7%) for the period 2030-2059 (MPI, KNMI, SMHI). The results of the present work show that climate change will bring a reduction of water resource availability and some alterations in the hydrological regime. The SWAT model, which proved to be a valuable operational tool for evaluating the potential impact of climate change on water resources, estimates a reduction of total water yield and a shift of the flow regime towards drier conditions, although the river type classification will probably remain essentially unvaried. A sever reduction of snowfall in the mountainous part of the basin was also estimated that is expected to impact the flow regime. However, it is important to take into account that several sources of uncertainties, which depend both on the used hydrological models and on the climate change scenarios, affect the predictions of the hydrological response of a river basin under climate change. In addition, some of the assumptions made (i.e. that land use does not change in the future) could be incorrect as climate change could also result in a significant alteration of land cover. Hence, we have to consider projections not as a predictive method, but as a tool that may be used to assess changes in process dynamics.

The primary focus of this task is the prediction of the effect of some stakeholder proposed prevention and mitigation measures as well as the impact of climate change scenarios on coastal aquifers regarding the groundwater flow and fate and the transport of contaminants. To be operational and practical, the calibrated numerical simulator FEFLOW was used to model the flow and solute transport in the four coastal aquifers under study. The modelling approach was based on a spatial discretization of the physical domain of the aquifer in three dimensions. Depending on the type of aquifer being modelled, the observed temporal variation in groundwater flow, the risk of saltwater intrusion, and the availability of flow and transport parameters and data, the appropriate modelling approach was selected. The outcome of the modelling task is integrated in the establishment and application of sustainable governance approaches for the four coastal aquifers. As the numerical modelling approach is an essential part of the multi-criteria Decision Support System (DSS), our modelling approach included climate change scenarios to model the impact of future rainfall data on predicted ground water levels, which may significantly impact both the available groundwater reserves and groundwater quality.

The possible application of membranes for CO2 separation in the treatment of non-valuable streams (e.g., flue gas of a power plant or cement industry) or valuable streams (e.g.,biogas) has been analyzed. Some selection criteria useful in the choice of membrane gas separation for CO2 capture are discussed to evaluate the advantages potentially offered by membrane systems. Membrane selectivity ranging from 30-50 (values of commercial membranes) to 100-500 (values of most promising laboratory membranes) and different feed/permeate pressure ratios were considered for the various cases. The composition and recovery of carbon dioxide in the membrane-treated stream were the target parameters taken into account as guidelines in the evaluation of the separation technology performance. General "maps" of CO2 permeate concentration versus CO2 recovery have been developed by means of a simple tool that takes into account the influence of the most importantp arameters affecting the membrane system performance (that is,membrane selectivity and permeation driving force).The analyses indicated that the separation depends on various interrelated factors: the membrane material (selectivity and flux), the operating conditions (pressure ratio), and the final requirements (CO2 recovery and composition).Also, the operational limit and the potentialities of the membrane gas separation technology were analyzed under these conditions.The "maps" proposed and utilized for CO2 separation are valid and can beutilized for other gas separations in which the membrane shows selectivities similar to those taken into account here.

Lakes are integrators of environmental and climatic changes occurring within their contributing basins. Understanding the complex behavior of lakes in a changing environment is essential to effective water resource management and mitigation of climate change. The ESA CCI Lakes is a multi-disciplinary project (https://climate.esa.int/en/projects/lakes/) creating the largest and longest consistent global record of five lake climate variables: lake water level, extent, temperature, surface-leaving reflectance, and ice cover. Phase 1 covered 250 lakes and phase 2 will cover up to 2000 globally. The distribution of the global dataset will be presented followed by a focus on Lake Trasimeno, a shallow eutrophic lake in central Italy included in the Long-Term Ecosystem Research (LTER) network. We used AI and Non-Parametric Multiplicative Regression (NPMR) to analyze the data. Chlorophyll-a in lake Trasimeno was dominated by a summer bloom initiating in July and peaking in early September and was largely predicted by the time variable - accounting for 87% of feature importance. The North Atlantic Oscillation was the next most important variable (4% feature importance) corroborated by NPand shown to be largely important during early to mid-September when a positive NAO, associated with high pressure and warm sunny weather, led to an increase in chlorophyll-a concentrations. Regional climatic indices as well as the more obvious nutrient drivers of algal blooms should therefore be considered in lake management. High Frequency chlorophyll-a and phycocyanin data from a WISPstation showed that rapid fluctuations visible in the satellite record are supported by in situ data.