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We report on the combination of multiple techniques (aircraft, eddy covariance and chambers) to assess CH4 emissions of several landfills in Italy. Chambers were able to characterize the spatial variability of the continuum of the landfill but not the presence of preferred localized fugitive emissions. The deploying of light aircraft and payloads in remote access areas to characterize large-scale emissions with the presence of multiple sources supported measures in areas not covered by the eddy covariance tower footprint. Landfills emissions where biogas extraction was present were on average an order smaller than landfill without any extraction, demonstrating the benefit of biogas extraction not only in terms of energy production but also of avoided GHGs emissions.

A model validation of the complex photochemical processes occurring in the gulf of Naples has been performed trough a measuring campaing carried out in July 2015. Tethered balloons were used in combination with PTRMS and GCMS to assess the vertical profiles of VOC in the Mount Vesuvius. Experimental data were compared with predictions obtained with the WRF model ran with FARM routine.

The characterization of volatile organic compounds (VOCs) emitted by landfills is an important topic because, although they represent a percentage below 1% of total emissions, can represent a risk for public health and environment. Some of them, such as benzene, toluene, ethyl-benzene and xylene isomers (BTEX) are in fact toxics or carcinogenic. Monitoring these compounds especially in landfills is thus essential although their concentrations, high at the source, are then diluted in the air. In 2015, a VOCs characterization from the biogas emitted from five landfills (Ampliamento Masseria, Masseria, Resit X, Novambiente and Resit Z) in"Terra dei Fuochi" area (Naples) was done to evaluate and describe its composition. Around 100 compounds belonging to 7 different chemical classes were identify from the biogas by using sorbent tubes and Thermal Desorption Gas Chromatography-Mass Spectrometry. Average concentrations of BTEX were approximately 29 mg/m3 in Ampliamento Masseria, 5-6 mg/m3 in Masseria and in Resit X, 3 mg/m3 in Novambiente and 0.5 mg/m3 in Resit Z. High concentrations of the terpene limonene, ?-pinene and p-cymene have been also detected. These preliminary results highlighted the potential risk for people living in the surrounding area and the need to apply strategies and policies for people security and air quality. The use of biogas for producing electric energy may decrease the concentrations of toxics VOCs reducing their burden in the atmosphere.

Foliar symptoms of grapevine leaf stripe disease (GLSD, a disease within the esca complex) are linked to drastic alteration of photosynthetic function and activation of defense responses in affected grapevines several days before the appearance of the first visible symptoms on leaves. The present study suggests a methodology to investigate the relationships between high-resolution multispectral images (0.05 m/pixel) acquired using an Unmanned Aerial Vehicle (UAV), and GLSD foliar symptoms monitored by ground surveys. This approach showed high correlation between Normalized Differential Vegetation Index (NDVI) acquired by the UAV and GLSD symptoms, and discrimination between symptomatic from asymptomatic plants. High-resolution multispectral images were acquired during June and July of 2012 and 2013, in an experimental vineyard heavily affected by GLSD, located in Tuscany (Italy), where vines had been surveyed and mapped since 2003. Each vine was located with a global positioning system, and classified for appearance of foliar symptoms and disease severity at weekly intervals from the beginning of each season. Remote sensing and ground observation data were analyzed to promptly identify the early stages of disease, even before visual detection. This work suggests an innovative methodology for quantitative and qualitative analysis of spatial distribution of symptomatic plants. The system may also be used for exploring the physiological bases of GLSD, and predicting the onset of this disease.

The aim of this study was to measure carbon fluxes using the eddy covariance approach of a large field of switchgrass starting from the field establishment of the crop. The eddy covariance approach, based on the covariance between fluctuations of vertical wind velocity and CO2 and vapour mixing ratios, has been largely used to determine the Net Ecosystem Exchange (NEE) of forest ecosystems. Few studies have been carried out on cultivated biomass crops and perennial grasses as switchgrass, and in particular under Mediterranean conditions. The eddy covariance technique allows to assess a reliable CO2 balance able to define the potential of the entire agro-ecosystem to act as source or sink of C. The high time-resolution measurements allows accurate daily, seasonal and annual quantification of C fluxes. Total switchgrass biomass yield was 6.8 t ha-1 (as dry matter) at final harvest (23 October). A continuous map of the spatial distribution of yield through several harvests has been also produced. The eddy covariance measurement revealed a good potential of switchgrass to store carbon during the seasons, with a NEE cumulated value during the whole vegetative season (from May to October) of 4.7 t C ha-1 while the GPP for the same period was 10.2 t C ha-1 and the ecosystem respiration Re was 5.5 t C ha-1., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 1844-1847

I microrganismi benefici utilizzati in agricoltura biologica possono instaurare interazioni con la pianta ospite in grado di proteggerla dalle malattie e di migliorarne la crescita e l’assorbimento di soluti e acqua. Quest’ultimo aspetto potrebbe peraltro divenire importante a causa di una prevedibile progressiva limitazione della disponibilità di acqua. Piante di lattuga sono state allevate in vaso, in ambiente controllato per temperatura, intensità luminosa e fotoperiodo. Le piante sono state trattate con formulati commerciali a base di Trichoderma sp., di Glomus sp., e di loro combinazioni anche con ulteriori microrganismi benefici. Per ciascun formulato, le applicazioni sono state realizzate secondo il seguente schema: alla semina; alla semina e al trapianto; alla semina, al trapianto e durante la crescita in vaso. Il consumo d’acqua è stato registrato mediante l’ausilio di appositi sensori per il contenuto volumetrico d’acqua nel suolo (VWC). Da parte nostra abbiamo inteso valutare contestualmente e in funzione del numero e del posizionamento delle applicazioni: l’attività dei prodotti contro Rhizoctonia solani inoculata al terreno successivamente e il loro effetto sull’utilizzo dell’acqua da parte della pianta. I dati ottenuti mostrano una maggiore attività dei prodotti quando sono stati applicati alla semina e al trapianto. La maggior parte dei microrganismi saggiati ha inoltre evidenziato un consumo d’acqua minore per unità di peso prodotto. I formulati a base di Trichoderma mostrano la migliore combinazione tra i parametri in prova.

Potentials advantages by the use of Eddy Covariance in biomass crops

In this chapter the Eddy Covariance network of Italy is presented, with a short introduction to each of the 29 sites that were active during the CarboItaly project. These sites provided a unique dataset for a better study and understanding of the carbon cycle of terrestrial ecosystems and the links between carbon sink capacity and the main environmental factors. After a number of examples of Eddy Covariance time series where it is possible to see the effect of interannual climate variability and disturbances and managements practices, an analysis of the role of the Carbon Uptake Period in the total Net Ecosystem Exchange (NEE) definition and a study of the effect of temperature and precipitation on the interannual variability of NEE are presented in order to show the way these data can contribute to a better understanding of the role and response of ecosystems to climate change.

La funzionalità delle colture legnose arboree da frutto sull'assorbimento della CO2atmosferica, e l'ammontare dello stoccaggio del carbonio che queste mettono in atto è stato scarsamente studiato rispetto a quanto sia stato analizzato negli ecosistemi forestali. Gli studi estensivi sull'efficienza degli impianti arborei ad agire come sink di carbonio atmosferico sono stati in parte sfavoriti dalle loro estensioni, generalmente troppo limitate per poter applicare le tecniche micrometeorologiche classicamente utilizzate in ambito forestale. Inoltre, l'ottica di considerare le colture agrarie non soltanto come forme produttive ma anche come risorse ambientali non è ancora un'ottica prevalente. La superficie italiana destinata a colture legnose (frutteti, vigneti, oliveti ecc.) è di circa 2.5 milioni di ha, che corrispondono al 25% della superficie boschiva italiana: il contributo di queste colture alla riduzione della COin atmosfera potrebbe essere non trascurabile. Negli ultimi cinque anni si sono svolti studi su diverse specie frutticole per determinare, tra le altre cose, la loro capacità di fissazione del carbonio.

The carbon balance of an afforested area in the Emilia-Romagna floodplain has been monitored for a 4-year period. Detailed measurements covering both above- and below-ground components of biomass production and accumulation were complemented by eddy-covariance measurements at the ecosystem level. Experimental results have been extrapolated in time by means of a process-based ecosystem model, so as to better assess the potential role of afforestation towards the carbon-reduction goals of the Kyoto Protoco

Eddy covariance technique is able to determine at the same time crop evapotranspiration (ETc) and carbon fixation over a large kind of agricultural and natural ecosystems. Switchgrass is recognized as a feedstock for biofuel production, the knowledge of water requirement under Mediterranean condition characterized by high temperatures during summer and water deficiency play an important role for switchgrass cultivation expansion and for its capability to assimilate CO2 from the atmosphere and consequently to act as sink of greenhouse gas (GHG). An Eddy covariance tower was established in a large switchgrass field at sowing time in Cadriano (Bologna, Italy) recording water fluxes in a high time resolution. Total amount of evapotranspiration during the whole vegetative season under rain fed conditions resulted 2962.2 m3 ha-1, at the same time carbon fixation (Gross Primary Production GPP) was 10.2 t C ha-1, the mean seasonal Water Use Efficiency (WUE), expressed by the ratio between kg C fixed and m3 of water lost by evapotranspiration, was 3.4 kg, meaning that for each m3 of water it is fixed 3.4 kg of carbon., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 2020-2021

The capability of an energy crop agro-system to act as sink or as a source of carbon is important in the frame of a sustainable production of energy. Many factors affect the sink-source capability of an ecosystems, that depends on assimilation and respiration. Eddy covariance is a direct method to measuring CO2 and H2O fluxes above a vegetative surface. This technique ascertains the exchange rate of CO2 across the interface between the atmosphere and a plant canopy. Eddy covariance approach has been largely used in the last decade to determine the Net Ecosystem Exchange in particular for woody trees ecosystems. Few studies have been carried out on cultivated biomass crops and perennial grasses and in particular under Mediterranean conditions, where the influence of high temperatures and dry periods may increase respiration then CO2 emission. The integration of the eddy-covariance CO2 fluxes measurements with the quantification of the total inputs introduced in a productive cycle will also give the possibility to assess the emissions of an entire crop production chain respect to his net ecosystem productivity, providing an indicator of which energy production chain will ensure the maximum CO2 absorption and the minimum impact of the carbon cycle., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 639-641

An orchard carbon fixation between 5-11 mmol m-2 s-1 has been recorded through eddy covariance technique during the summer for a table grape in Southern Italy. The total daily ecosystem exchange was equal to 2.07 g C/m2 day in 2001, and 1.68 in the warmer 2002. The latent heat of evapotranspiration was 40% Rn in 2001 and about 30% in 2002. Eddy covariance allowed to have information on the water use efficiency (WUE) of the vineyard during the two years, that was, at midday, equal to 0.0012 in 2001 and 0.0015 in 2002. WUE, determined at canopy scale, is very important mainly in those environments where water is a limiting factor and a correct irrigation schedule is necessary.

Obiettivo di questa ricerca era la misura del bilancio energetico e dei flussi evapotraspirativi, evaporativi, e di CO2 da un vigneto di 'Sangiovese', allevato a controspalliera nella zona di produzione del "Brunello di Montalcino" (SI). Le misure sono state effettuate in due annate diverse (2005 e 2006) nelle fasi fenologiche di "chiusura del grappolo" e "invaiatura". I dati misurati nelle due annate mostrano una grande ripetibilità, dimostrando la robustezza della metodologia applicata. L'evapotraspirazione misurata si è attestata nei due anni su valori dell'ordine di circa 4 mm/d, con un contributo dell'evaporazione dal terreno tra i filari piuttosto basso, dell'ordine di 0,5 mm/d. Il flusso di COha mostrato che i valori di assimilazione giornaliera nelle ore diurne si attestavano, mediamente, su 7 µmol m-2 s-1 di carbonio, mentre i valori di respirazione si attestano intorno alle 1,7 µmol m-2 s-1. In entrambi gli anni le misure hanno mostrato una asimmetria corrispondente ad un calo del flussi di CO2 nelle ore pomeridiane rispetto a quelle mattutine. Lo scambio totale dell'ecosistema è stato di circa di -3,3 g di carbonio per m2 di terreno. Infine, considerando un periodo vegetativo medio annuo e una durata media del giorno di 10 ore, risulta che un ettaro di vigneto fissa circa 6 t ha per anno di carbonio.

This study reports the seasonal assessment of energy balance components and carbon dioxides fluxes over a drip irrigated kiwifruit orchard, with a Leaf Area Index (LAI) of 3 at full canopy development. The most remarkable amount of energy partitioning throughout the whole season was due to latent heat flux that had values approximating to those of sensible heat flux (about 200 W m-2 s-1 at midday) only in May, when leafy biomass was still developing. From June to September, latent heat flux kept constantly at about 50% of net radiation (Rn), and did not appear to be influenced by the air temperature, very high in its maximum values during the three months of June, July, August. Canopy carbon assimilation reached maximum values of about ¡V14 ƒÝmol m ¡V2 s ¡V1 during May and June, and values decreased in July and August respectively to ¡V12 and ¡V10 ƒÝmol m ¡V2 s ¡V1 , turning to ¡V13 ƒÝmol m ¡V2 s ¡V1 again in September. Going on with the season, a marked decrease of the canopy photosynthesis was observed. A diurnal decline in photosynthesis similar to that recorded from single leaf measurements is reported and an amount between 60% and 75% of the total carbon is fixed by the orchard in the morning between 7 and 12.30. The seasonal timing and the amplitude of the net system carbon flux as well as the ones of the components fluxes corresponding to assimilatory and respiratory processes has been quantified. The Net Ecosytem Exchange (NEE) of the kiwifruit system was at around 3 t of carbon during the seven months leafy period (useful to produce 12.5 t total biomass ha-1 , more than 50% partitioned to perennial structures,), when 8.5 t of carbon were lost in ecosystem respiration. Such fluxes are the sum of contribution to both kiwifruit plants and cover crop, present during all the season. Daily and seasonal canopy water use efficiency (WUE) is also reported. Midday averaged monthly values indicate that WUE is 0.0027 and 0.0029 in May and June respectively, and decreases to 0.0022 in July up to a minimum of 0.0018 in August. WUE values increase after that time reaching higher values in September (0.0033) and October (0.0046). In each month, the diurnal trend shows constant higher water use efficiencies in the morning hours, evidently matching the photosynthetic daily patterns.

The emissions of volatile organic compounds, VOC, from plants have strong relevance for plant physiology, plant ecology and atmospheric chemistry. We report here the emission rates and the ecophysiological behaviour of the Mediterranean plant species Chamaerops humilis L., Pistacia lentiscus L. and Juniperus phoenicea L. Emission measurements made by means of a dynamic branch enclosure under field condition indicated that Chamaerops humilis is a strong emitter of isoprene at a diurnal rate of 41.4 ng m-2 s-1. Lower daily emission rates were measured for the monoterpene emitter shrubs P. lentiscus (13.9 ng m-2 s-1) and J. phoenicea (4.1 ng m-2 s-1) compared to C. humilis. A good correlation was found between isoprenoid emission rate and temperature. Monoterpene emission from the reservoir of Pistacia and Juniperus and isoprene released by Chamaerops leaves enhanced during periods of increasing irradiation and temperature in the middle of the day. The daily trends of photosynthesis showed higher values at morning and a greater CO2 assimilation in Pistacia lentiscus leaves compared to the other species. For leaf transpiration we observed a slight decrease in the afternoon in Chamaerops leaves and a fairly constant transpiration in the other two shrubs. Xylem water potential measurements indicated that all the species were not subjected to a severe drought stress.

In the present work a simplified model, based on the parameterisation of a growing boundary layer over a coastal discontinuity , has been used to estimate the temporal evolution of the mixed layer height during the PianosaLab experimental campaigns. The bi-dimensional model was applied over the limited surface domain of the Pianosa island. The input parameters of the model derive from the sonic anemometer measurements collected at a ground site (Vaccari et al., same issue).

Si presentano i risultati del progetto regionale per lo studio delle gelate tardive

Intermittent irrigation proved to be very good both for plant protection and for a better water use (greater irrigated area, lower risk of oxygen deficiency in the root zone). The goal of this research is to investigate about the efficiency of different sprinkler types and water volumes in enhancing air temperature in the canopy layer and to optimise the amount and the cycling of the water applied. This knowledge is important for the improvement of this new technique, firstly proposed in Italy in 1992 by Ferri et al. This paper reports some results obtained from a three-years long experiment designed at this scope.

Emission rates of monoterpenes released by apple (Malus domestica Bortkh) and cherry (Prunus avium L.) were estimated at different phonological stages. These measurements employed a dynamic flow-through Teflon chamber, sample collection onto cartridges filled with graphitised carbon and thermal desorption gas chromatography-mass spectrometry (GC-MS) for identification and quantification of the emitted volatiles. At full bloom the release of monoterpene hydrocarbons from cherry flowers was 1213 ng g-1 dry weight (DW) h-1, exceeding by approximately three-fold the emission rate of apple flowers (366 ng g-1 DW h-1). Observed seasonal variations in biogenic volatile organic compound (VOC) emissions ranged over several order of magnitudes. At fruit-set and ripening stages, in fact, the hydrocarbon emission dramatically decreased reaching the lowest values at harvest time when leaves were fully mature (3-9 ng g-1 DW h-1). Wide diversity in the composition of compounds from the species studied was also recorded. At blooming, linalool contributed significantly to the monoterpene emission from apple (94% of the emitted carbon) while ±-pinene and camphene represented on average more than 60% of the total emitted volatiles from cherry flowers. Among the monoterpenes identified in flowers, ±-pinene, camphene and limonene were also found in the foliage emission of both species. Fruit trees are relevant monoterpene emitters only at blooming and thus for a short period of the vegetative cycle. When leaves are fully developed, the carbon loss due to monoterpene emission related to the photosynthetically carbon gain is negligible.