Sara Di Lonardo

Effect of different extraction methods on fiber quality of nettle (Urtica dioica L.)

Chemical extraction, water retting, microbiological and enzymatic methods were applied on entire nettle stalks and/or unretted decorticated fiber of a selected fiber nettle clone. Morphological and mechanical properties and chemical composition were then determined on fiber samples. The first interesting result concerned the good degree of separation between fibers and shives obtained by mechanical scutching applied on stalks stored for 1 year, probably resulting from natural retting processes occurring during the storage. Microbiological retting (anaerobic plus aerobic bacteria) of entire stalks and/or unretted decorticated fiber produced fibers with a higher quality than water retting. Both enzymes used (Viscozyme ® L and Pectinex® Ultra SP-L), improved fiber quality if EDTA was added. The enzyme vat retting gave good results on both water-retted fibers and unretted decorticated fibers, while the spray enzyme treated fibers usually displayed thicker diameter, lower cellulose content and, for Viscozyme ® L, lower strength values, without differences between the two storage methods used after enzyme application.

The Effects of Biochar and Its Combination with Compost on Lettuce (Lactuca sativa L.) Growth, Soil Properties, and Soil Microbial Activity and Abundance

Impacts of biochar application in combination with organic fertilizer, such as compost, are not fully understood. In this study, we tested the effects of biochar amendment, compost addition, and their combination on lettuce plants grown in a soil poor in nutrients; soil microbiological, chemical, and physical characteristics were analyzed, together with plant growth and physiology. An initial screening was also done to evaluate the effect of biochar and compost toxicity, using cress plants and earthworms. Results showed that compost amendment had clear and positive effects on plant growth and yield and on soil chemical characteristics. However, we demonstrated that also the biochar alone stimulated lettuce leaves number and total biomass, improving soil total nitrogen and phosphorus contents, as well as total carbon, and enhancing related microbial communities. Nevertheless, combining biochar and compost, no positive synergic and summative effects were observed. Our results thus demonstrate that in a soil poor in nutrients the biochar alone could be effectively used to enhance soil fertility and plant growth and biomass yield. However, we can speculate that the combination of compost and biochar may enhance and sustain soil biophysical and chemical characteristics and improve crop productivity over time.

Composition and emission of VOC from biogas produced by illegally managed waste landfills in Giugliano (Campania, Italy) and potential impact on the local population

The composition in Volatile Organic Compounds (VOC) of the biogas produced by seven landfills of Giugliano (Naples, Campania, Italy) was determined and VOC emission rates assessed to verify if these compounds represent a potential threat to the population living nearby. VOC composition in the biogas could not be predicted, as heterogeneous waste was dumped from the late 1980s to the early 2000s and then underwent biological degradation. No data are available on the amount and composition of VOC in the biogas before the landfills closure as no operational biogas collection system was present. In this study, VOC composition was determined by gas chromatography-mass spectrometry (GC-MS), after collecting samples from collection pipes and from soil fractures in cover soil or capping. Individual VOC were quantified and data compared with those collected at two landfills in Latium, when they were still in operation. Relevant differences were observed, mainly due to waste aging, but no specific VOC revealing toxic waste dumping was found, although the concurrent presence of certain compounds suggested that dumping of industrial wastes might have occurred. The average VOC emission was assessed and a dispersion model was run to find out if the emitted plume could affect the health of population. The results suggested that fugitive emissions did not represent a serious danger, since the concentrations simulated at the neighboring cities were below the threshold limits for acute and chronic diseases. However, VOC plume could cause annoyance at night when the steady state conditions of the atmosphere enhance pollutants accumulation in the lower layers. In addition, some of the emitted VOC, such as alkylbenzenes and monoterpenes, can contribute to tropospheric ozone formation.

Chestnut Management Practice as Tool for Natural and Cultural Landscaping

Chestnut (Castanea sativa Mill.) is one of the most economically multipurpose species of the Mediterranean region, important not only for the production of fruit and timber, but also for its contribution to landscape and environment and its socio-economic and cultural value as eco-cultural niche. For these reasons, chestnut management is today discussed since certain practices could affect soil properties and also be associated with losses of biological and cultural diversity, included provision of socio-cultural and environmental services. The objective of this work is to evaluate management options in chestnut coppices and of how much they could represent a choice from both plant ecophysiology and cultural point of views. Soil and plant ecophysiology measurements were performed in Tuscan Apennine areas before and after two cutting methods. Data showed that pollarded tree physiology was similar to pruning tree one’s when it was wet but it was statistically different in the summer seasons affecting also soil water retention characteristics. These results demonstrated the importance of these measures in describing and indicating tree functional status. Moreover, the silvicultural practices modified not only the ecosystem attributes and the canopy cover characteristics but they also transformed the forest perception, an important factor to consider if expecting to engage local people in making a contribution for active landscaping.

A Preliminary Characterization of Wools from Italian Native Sheep Breeds: Opportunities for New Productions and the Development of Rural Areas

Italian sheep breeds, either local or native, produce about 14,000 tons of greasy wool per year included in the range of moderate to poor quality wools. In order to exploit neglected local textile resources, this study focused on a preliminary descriptive analysis of wools from some Italian native sheep breeds by measuring diameter and length of wool fibers. Variability emerging from data was described using multivariate techniques. A graphic description of different wools was provided by applying cluster analysis in order to distinguish wool characters by sheep breeds and clearly identify wool groups according to fiber variables.

Neglected Wools: Fundamental Steps to Counteract the Loss of Potentially Valuable Materials Derived from Native Sheep Breeds

In order to enhance the textile value of Italian native and local wools, research projects were carried out by starting mapping wools from some Italian sheep breeds through a preliminary morphological characterization of wool fibres. Furthermore, textile processing procedures differing from the commonly used woolling techniques have been set up. The results have shown that, at national level, native and local wools, beyond being more widely employed in the carpets production, could be also used in the higher added value sector of clothing and fashion.