• Energy Research

Zinc (Zn) is naturally present in soils and constitutes an essential micronutrient for plants. Mining, industrial, as well as various agricultural activities all contribute to increasing the Zn concentrations in soils to levels that are toxic for plants. The aim of this study was to evaluate the capacity of field crops to remove Zn from contaminated soils. The experimental design included 28 treatments, comprising seven field crops (Hordeum vulgare L., Ricinus communis L., Phaseolus vulgaris L., Brassica juncea Czem., Sorgum vulgare L., Spinacea oleracea L., Solanum lycopersicum L.) and four Zn levels (0, 500, 1000, 1500 mg kg-1) applied to soils. The dry weight (DW) of the aboveground biomass of R. communis and S. lycopersicum increased significantly as the Zn concentration in the soil increased, whereas the DW significantly decreased in P. vulgaris, B. juncea and S. vulgare. Results indicated that S. oleracea was the most efficient in concentrating Zn in the aboveground tissues, followed in decreasing order by H. vulgare, S. lycopersicum, R. communis, S. vulgare, P. vulgaris, and B. juncea. H. vulgare resulted the most efficient in accumulating Zn both in fruit and in leaves and stems, whereas S. lycopersicum resulted the most efficient in accumulating Zn in roots. The BAF and TF values indicated that H. vulgare and S. oleracea resulted being suitable for Zn phytoextraction, whereas the remaining crops being suitable for Zn phytostabilization. These results highlight the phytoremediation potential of the seven analysed crops.

Abstract Cultivation of sweet sorghum for the production of bioenergy is an attractive option to cope with the challenges of climate change and variability. In fact, on one hand it represents an interesting strategy of mitigation and, on the other, the use of drought resistant species could be considered as an opportunity of adaptation to the change of precipitation patterns. Anyway, when considering the production of agricultural feed stocks, particular attention should be addressed to the environmental sustainability of field production in order to avoid trade-offs in relation to food production, land use and pressure on the water resources. In this context, the cultivation of drought-tolerant energy crops as sweet sorghum ( Sorghum vulgare (L.) var. Saccharatum) could be an interesting option. On the bases of these considerations, the current study had the aims i) to monitor the sweet sorghum growth and productive responses to different water treatments, in order to assess the extent of tolerance to constant water stress and ii) to assess the potential for first and second-generation bioethanol production obtainable from soluble sugars and residual biomass at two different development stages, flowering and physiological maturity. Results show that the length of the growing period should be decided on the bases of the objective pursued. If the objective is just the production of bioethanol, a longer cultivation period could be more suitable, but, on the contrary, if the objective is more addressed to an optimization of water, flowering should be considered the best harvest time.

A preliminary study was conducted to analyze the sustainability of barley production through: (i) investigating sensor-based nitrogen (N) application on barley performance, compared with conventional N management (CT); (ii) assessing the potential of the Normalized Difference Vegetation Index (NDVI) at different growth stages for within-season predictions of crop parameters; and (iii) evaluating sensor-based fertilization benefits in the form of greenhouse gasses mitigation. Barley was grown under CT, sensor-based management (RF) and with no N fertilization (Control). NDVI measurements and RF fertilization were performed using a GreenSeeker™ 505 hand-held optical sensor. Gas emissions were measured using a static chamber method with a portable gas analyzer. Results showed that barley yield was not statistically different under RF and CF, while they both differed significantly from Control. Highly significant positive correlations were observed between NDVI and production parameters at harvesting from the middle of stem elongation to the medium milk stage across treatments. Our findings suggest that RF is able to decrease CO2 emission in comparison with CF. The relationship between N fertilization and CH4 emission showed high variability. These preliminary results provide an indication of the benefits achieved using a simple proximal sensing methodology to support N fertilization.

Summary During recent years, the opportunity to use energy crops for the production of biofuels aroused many interest by virtue of the potential reduction of green house gasses emissions associated to their large-scale use. Nevertheless, many studies highlight that the substitution of fossil fuels with biofuels from energy crops can lead up to serious problems related to the pressure on water resources. The present research had the aim to investigate the relations existing between biofuels production and the pressure on water resources, and how these relations are affected by climate variability. To this aim, the water footprint of maize cultivation in Tuscany (central Italy) was computed and its trend was analyzed during the last 55 years in relation to climate variability with particular attention to precipitations. The results demonstrated that the WF was affected by climate variability mainly through the effect of climate on the crop cycle. The total WF decreased over time but an increase of the blue component was found due to the change in precipitation patterns and to the rise of temperatures. Concerning the gray WF, despite a decrease in the last 55-years period mainly due to precipitation decrease, there was a reduction in N uptake by the crop and an accumulation of nitrate into the soil.

Results show that the year-to-year quality variation of wines produced in North and Central Italy depends on the large-scale climate variability, and that the wine quality improvement in the last four decades is partially due to an increase of temperature and to a decrease of precipitation in West and Central Mediterranean Europe (WME; CME). In addition, wine quality is positively correlated with air temperature throughout the entire active period of the grapevine, weakly negatively correlated with precipitation in spring, and well negatively correlated in summer and fall. The month-to-month composites of the NAO anomaly show that, in years of good quality wine, this anomaly is negative in late spring, oscillates around zero in summer, and is positive in early fall; while, in years of bad quality wine, it is positive in late spring and summer, and negative in early fall, i.e. its polarity has an opposite sign in spring and fall in good versus bad years. The composite seasonal maps show that good wines are produced when the spring jet stream over the Atlantic diverts most of the weather perturbations towards North Europe, still providing a sufficient amount of rainwater to CME; when summer warming induced by southerly winds is balanced by the cooling induced by westerly winds; and when a positive geopotential anomaly over WME shelters CME from fall Atlantic storms. Bad quality wines are produced when the jet stream favors the intrusion of the Atlantic weather perturbations into the Mediterranean. Results suggest that atmospheric pattern persistencies can be used as precursors for wine quality forecast.

PurposeAgricultural workers represent an important part of the population exposed to high heat-related health and productivity risks. This study aims to estimate the heat-related productivity loss (PL) for moderate work activities in sun and shady areas and evaluating the economic cost locally in an Italian farm and generally in the whole province of Florence. Benefits deriving by working in the shade or work-time shifting were provided. Comparisons between PL estimated in Mediterranean (Florence, Italy) and subtropical (Guangzhou, China) areas were also carried out.Design/methodology/approachMeteorological data were collected during summers 2017–2018 through a station installed in a farm in the province of Florence and by two World Meteorological Organization (WMO)‐certified meteorological stations located at the Florence and Guangzhou airports. These data were used to calculate the wet-bulb globe temperature and to estimate the hourly PL and the economic cost during the typical working time (from 8 a.m. to 5 p.m.) and by advancing of 1 h and 2 h the working time. Significant differences were calculated through nonparametric tests.FindingsThe hourly PL and the related economic cost significantly decreased (p < 0.05) by working in the shade and by work-time shifting. Higher PL values were observed in Guangzhou than in Florence. The decrease of PL observed by work-time shifting was greater in Florence than in Guangzhou.Originality/valueUseful information to plan suitable heat-related prevention strategies to counteract the effects of heat in the workplace are provided. These findings are essential to quantify the beneficial effects due to the implementation of specific heat-related adaptation measures to counter the impending effects of climate change.

A mechanistic growth model was used to evaluate the mean yield and yield variability of grapevine Vitis vinifera L. under current and future climates. The model used was previously validated using field experiment data. The effect of elevated CO2 on grapevine growth was also considered. Adaptation of 2 varieties (Sangiovese and Cabernet Sauvignon) to scenarios of increased CO2 and climate change, and potential changes in agricultural risk (i.e. inter-seasonal variability), were examined. Before testing the effect of climate scenarios, we analysed the sensitivity of modelled grapevine yield to arbitrary changes in the 3 driving variables (temperature, solar radiation and CO2). The results showed the model to be more sensitive to changes in CO2 concentration and temperature than to changes in radiation. Analyses made using transient GCM (general circulation model) scenarios (UKTR and GFDL) showed different changes in mean fruit dry matter for the different scenarios, whereas mean total dry matter, and fruit and total dry matter variability, were predicted to increase under almost all the scenarios. Predictions based on equilibrium scenarios (UKLO and UKHI) gave similar results. For Sangiovese, variety adaptation analysis suggested a better adaptation in terms of mean production, but a worse adaptation in terms of yield variability.