92 research outputs found

    Analysis of spatio-temporal Bactrocera oleae (Diptera, Tephritidae) infestation distributions obtained from a large-scale monitoring network and its importance to IPM

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    Bactrocera oleae is the key-pest considered in the “Olive-oil quality improvement project” in Tuscany (Italy). In this region, a network of 286 representative farms has been created in 2002 for monitoring weekly olive fruit-fly infestations, and the obtained data have been used in advising farmers on B. oleae control. The field observations were made by the regional extension service, and data have been collected from an internet-based monitoring network implemented in the Landscape Entomology Laboratory (LELab) of Scuola Superiore Sant’Anna. In this paper, we rely on the Geographic Positioning System (GPS) to locate the monitoring farms and make use of farm-specific information to analyze the regional spatial pattern of B. oleae infestions. Data analysis has been performed with Arcview 8.2, and we used variograms to model autocorrelations between sample points and cross-validation to identify the most reliable index. We consider the utility of Geographic Information System for spatial analysis at the landscape (or large) scale and kriging technique to interpolate between sample points. The resultant map can be used to predict the beginning of B. oleae infestations

    Soil conservation and ecosystem services from agroforestry systems: a GIS-based approach for soil erosion in Central Italy

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    Preserving natural resources, such as soil, is one of the major challenge for agriculture, in the view of developing sustainable adaptation strategies to climate change. Soil loss by water erosion is a critical issue in the Mediterra - nean region due to high rainfall erosivity caused by the increased frequency of extreme precipitation events. In Tuscany, the risk of soil erosion is exacerbated on arable soil of hilly areas, where the persistent application of conventional tillage is associated with: (i) long periods with bare soils within the crop rotation, (ii) poor herba- ceous vegetation cover due to low biomass productivity and (iii) scarce presence of trees on farmland. Agrofore - stry systems - “the practice of deliberately integrating woody vegetation (trees or shrubs) with crop and/or ani- mal systems to benefit from the resulting ecological and economic interactions” - can reduce soil erosion risk by enhancing cover-management factor. In this study the (R)USLE (Revised Universal Soil Loss Equation) was im- plemented on a GIS-based model in order to assess the potential of diferent agroforestry systems in decreasing soil erosion risk on arable land below the tolerance threshold (11 Mg ha-1 yr-1). The JRC-EU map proposed by Pa- nagos et al. (2015) was used for rainfall erosivity, whereas the agroforestry P-factor values were derived from Delgado & Canter (2012). The reference scenario, based in current soil uses (Corine Land Cover 2012) allowed to determine the baseline of potential soil losses on arable land in Tuscany and to identify areas characterized by the highest risk of erosion. About 50% of the cropland in the study area, 450,000 ha, has a severe soil erosion risk, more than 33 Mg ha-1 yr-1 of soil loss.The development of alternative scenarios, based on the possible implemen- tation of agroforestry systems, allowed to highlight that: (i) alley cropping systems (P-factor from 0.1 to 0.5) would reduce soil loss rate under the tolerance threshold on 60 % of the arable land of Tuscany; (ii) the 11% of the arable land would urgently need high conservative agroforestry practices (P-factor less than 0.1) in order to reduce soil loss below the tolerance threshold

    Microwave-assisted FeCl3-catalysed production of glucose from giant reed and cardoon cellulose fraction and its fermentation to new generation oil by oleaginous yeasts

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    The replacement of fossil fuels and materials with biofuels and bioproducts is a crucial current global goal. Biorefining of lignocellulosic biomass generates pentose and hexose sugars which can be converted into several added-value bio-based compounds. Among biofuels, biodiesel is one of the most promising renewable energy sources since it does not require new technology and engines for its use. Traditional biodiesel is produced on the industrial scale starting from vegetable oils obtained from oleaginous crops, such as palm oil, rapeseed oil and sunflower oil. However, most of the oleaginous plant species are food crops, determining the ethical debate on the right use of these renewable resources and the competition between the energy industry and food chain. An innovative and promising solution is represented by single cell oil (SCO) produced from oleaginous yeasts. This new generation oil, if obtained from low or negative value industrial waste, represents a promising platform chemical for the production of biodiesel, biosurfactants, animal feed and biobased plastics [1]. This study investigated the microwave-assisted FeCl3-catalysed hydrolysis of giant reed (Arundo donax L.) and defatted cardoon (Cynara cardunculus L.) cellulose fractions to give glucose. Giant reed is a promising energy crops able to grow on marginal lands, while cardoon stalks are the crop residue in the production of vegetable oil. A preliminary acid pretreatment was adopted for giant reed [2], while steam-explosion pretreatment was performed on cardoon [3], both allowing a significant removal of xylan fractions. Under different reactions conditions, the microwave-assisted FeCl3-catalysed hydrolysis converted the two pretreated feedstocks into glucose-rich hydrolysates which were employed as fermentation medium for the production of SCO by the oleaginous yeast Lipomyces starkeyi DSM 70296. For giant reed, the low production of furanic compounds enabled the direct fermentation of undetoxified hydrolysates, while for cardoon the furfural removal was necessary before the fermentation step. After hydrolysis, for both hydrolysates the fermentation provided promising lipid yields (~14 wt%) and oil content (~25 wt%). Figure 1 shows the process layout of the implemented third-generation biorefinery scheme. The SCO appears a valid candidate for the production of new generation biodiesel with good oxidative stability and cold flow properties. Moreover, it resulted very similar to palm and rapeseed oils, usually employed as a renewable source for the production of traditional biodiesel

    Aboveground Yield and Biomass Quality of Giant Reed (Arundo donax L.) as Affected by Harvest Time and Frequency

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    Giant reed (Arundo donax L.) is a perennial rhizomatous grass producing high biomass yields in temperate and warm climates under rainfed and reduced input conditions. Harvest time and frequency typically affect the productivity and suitability for energy conversion of energy crops. In order to evaluate the effect of different cutting managements on biomass yield and quality of giant reed, three single harvest (SH) and six double harvest (DH) systems were compared. Biomass yield, leaf mass ratio, dry matter (DM), and ash content were assessed for each harvest. Over the 2 years of study, giant reed demonstrated good productivity levels both when harvested once a year and twice a year (about 30 Mg ha−1) without significant differences between the treatments. Regarding double-cut regimes, overall yields were significantly reduced by delaying the second cut from autumn to winter (32.9 vs 30.2 Mg ha−1), and the percentage of the first cut with respect to the overall yield varied from 55 to 80 %. Biomass quality was also significantly affected by harvest time and frequency. The biomass obtained in double harvest systems showed higher average moisture levels (about 40 % DM) and ash concentrations ranging from 4.7 to 8.7 %. In contrast, single harvest systems led to a drier biomass (47–57 % DM) and reduced mineral contents (3.4–4.8 % ash). The feasibility of double-cut management should therefore be considered in terms of the specific giant reed-based supply chain, with particular regards to the storage and conversion technology adopted

    Double row spacing and drip irrigation as technical options in energy sorghum management

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    The effect of two row spacing configurations and four water supply levels was investigated on sweet and fibre sorghum in Central Italy for two consecutive years. Results highlighted the influence of both irrigation and row spatial configuration on crop productivity. Indeed, several studies have pointed out the positive response of sorghum to irrigation in Mediterranean climate, as in this environment water stress represents one of the main limiting factors on crop productivity. On the other hand, few attempts have been made to explore the role of row spacing on energy sorghum productivity. Results outlined an average increase in sorghum dry biomass yield ranging from +23% to +79% at variable rates of water supply as compared to rainfed control. The positive effect of irrigation was also observed on leaf area index and radiation use efficiency. Moreover, we observed a crop yield increase, from 9% to 20%, under double row spacing compared to the standard planting pattern ( i.e. single row spacing). Finally, it was confirmed the efficient use of water by sorghum and the great ability of sorghum to increase its biomass yield in response to increasing volumes of water supplied. Therefore, this work suggests how row spacing configuration and drip irrigation could be feasible technical options to increase sorghum biomass yields in Mediterranean environments. These techniques should be experienced by farmers towards a sustainable intensification of current cropping systems

    An on-farm rotational grazing trial: restricting access time to pasture did not affect the productivity of a dairy sheep flock in spring

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    In the Mediterranean area, semi-extensive mixed farming systems characterise the inland landscape and guarantee the maintenance of several agroecosystem services. Rationed and rotational grazing have been proposed as efficient agroecological practices for sustainable intensification. Previous studies have highlighted that, during spring, restricted access time to pasture of below four hours per day decreases herbage intake and milk production of rotationally stoked ewes. The aim of this study was to assess the effect of restricted access time on daily herbage intake and milk productivity of Sarda ewes under rotational grazing management in a real farm located in southern Tuscany. The entire flock of 145 lactating ewes was allotted two homogenous groups and rotationally stoked on a grass-legume mixed pasture and fed about 1.7 kg of DM ewe(-1) d(-1) of supplementation. Each group was then assigned to the following treatments: two hours per day of access time to pasture, from 10:00 to 12:00 CET, and four hours per day of access time to pasture, from 10:00 to 14:00 CET. Data on herbage yield and quality, dry matter intake and milk yield were collected from April 5 to May 10, 2018. The rotational grazing schedule was conducted allowing for abundant herbage and exploiting high-nutritive biomass of the upper horizon sward. The results of our on-farm experiment showed that restricting daily access time to pasture down two hours did not reduce the potential daily herbage intake and the milk performance of dairy ewes rotationally stocked on a mixed pasture in spring. Our study also highlighted the capacity of ewes to self-regulate the herbage intake in order to meet their energy requirements, when neutral detergent fibre is not a limiting factor. Our outcomes should encourage researchers and farmers to co-design further on-farm experiments

    Carbon Budget of an Agroforestry System after Being Converted from a Poplar Short Rotation Coppice

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    Poplar (Populus L. spp.) Short Rotation Coppice systems (SRCs) for bioenergy production are being converted back to arable land. Transitioning to Alley Cropping Systems (ACSs) could be a suitable strategy for integrating former tree rows and arable crops. A field trial (Pisa, Central Italy) was set up with the aim of assessing the C storage of an ACS system based on hybrid poplar and sorghum (Sorghum bicolor L. Moench) and comparing it with that of an SRC cultivation system. The carbon budget at the agroecosystem scale was assessed in the first year of the transition using the net biome production (NBP) approach with a simplified method. The overall NBP for the SRC was positive (96 40 g C m2 year1), highlighting that the system was a net carbon sink (i.e., NBP > 0). However, the ACS registered a net C loss (i.e., NBP < 0), since the NBP was 93 56 g C m2 year1. In the first year of the transition, converting the SRC into an ACS counteracted the potential beneficial eect of C storage in tree belowground biomass due to the high heterotrophic respiration rate recorded in the ACS, which was fostered by the incorporation of residues and tillage disturbance in the alley. Additional years of heterotrophic respiration measurements could allow for an estimate of the speed and extent of C losses
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