1,721,002 research outputs found
Soils on Recent Tephra of the Somma–Vesuvius Volcanic Complex, Italy
No full textThe Somma–Vesuvius volcanic complex emitted huge quantities of volcanic materials over a period from before 18,300 years BP to 1944. The activity during the last period, from post-AD 1631 to 1944, primarily produced lava and pyroclastics via effusive and strombolian eruptions. We
investigated the pedogenesis on rocks formed from post-AD 1631 to 1944, occurring on the slopes of Mt. Vesuvius up to Gran Cono Vesuviano and in the northern valley separating Vesuvius from the older Mt. Somma edifice. Pertinent morphological, physical, chemical, and mineralogical (XRD and FT-IR) soil properties were studied. The results indicated the existence of thin and deep stratified soils on lava, as well as the presence of loose detritic covers formed via pyroclastic emplacement and redistribution. The soils showed minimal profile differentiation, frequently with layering recording the episodic addition of sediments. We found that the dominant coarse size of primary mineral particles was preserved, and there was a low level of clay production. The main mineralogical assemblage present in sands also persisted in clays, indicating the physical breaking of the parent material. Chemical weathering produced mineral modifications towards the active forms of Al and Fe and was also attested in selected soils by glass alteration, allophane production, and the presence of analcime in clay as a secondary product from leucite. The differences in glass
lteration and analcime production found in the selected soils on lava were related to soil particle size and soil thickness. Concerning the youngest soil present on Gran Cono Vesuviano, other factors, such as the substratum’s age and site elevation, appeared to be implicated
INFLUENZA DELL’AMBIENTE COLTURALE E DELL’EPOCA DI TRAPIANTO SU SIMBIOSI, ASSORBIMENTI NUTRIZIONALI, CRESCITA, PRODUZIONE E QUALITA’ DELLA FAVA (Vicia Faba L. major Hartz) DA CONSUMO FRESCO, IN REGIME CONVENZIONALE O BIOLOGICO, IN CAMPANIA
No full textIn 2011-12 and 2012-13 research was carried out on fababean in Portici (Naples), with the purpose to evaluate the effects of crop environment and method as well as transplanting time on Rhizobium dynamics, nutrient absorption, fresh pods yield and seeds quality. With this respect, two crop environments (open field and greenhouse), two crop methods (conventional and “organic”) and five transplanting times (27 September, 11 October, 25 October, 8 November, 22 November) were compared.
The root active tubercles number was greater in open field compared to greenhouse and in the third transplanting time. There were no significant differences between the conventional and “organic” method. About 70% of roots tubercles was located in 0-15 cm soil depth, while the remaining 30% was detected between 15 and 35 cm.
The cultivation environment did not significantly affect the whole plant nitrogen concentration, but the nitrogen values were significantly higher in greenhouse grown flowers than in the field ones; conversely, a greater seeds nitrogen accumulation was recorded in open field compared to that obtained in protected environment. Nitrogen concentration was higher under the first transplanting time than with the third, except for the seeds, showing no significant differences between the two crop cycles. As concerns the crop method, the “organic” management caused a higher nitrogen concentration in the whole plant, while no differences were recorded between the two methods with regard to each organ concentration. Nitrogen concentration was higher in the pods harvested in open field than in those produced in greenhouse, while the opposite trend was detected for the flowers. Moreover, the first transplanting had a better effect on flowers nitrogen concentration, whereas the third one was more beneficial to the seeds. Finally, with reference to the crop method, the highest values of the substance provided by the pods from plants grown in organic way and by the seeds obtained by the conventional method. The nitrogen concentration detected in the leaves attained the highest level in the vegetative phase and the lowest one at fruiting end. Similar trend was shown by shoots, whereas the roots nitrogen concentration displayed a reduction only at the end of crop cycle. The pods showed the highest nitrogen concentration at full fruiting, while no differences were recorded for the seeds.
Phosphorus concentration was higher in greenhouse than in open field. Similarly, there was a greater phosphorus accumulation in greenhouse grown flowers than in the open field ones.
Transplanting time significantly affected phosphorus concentration in the whole plant as well as in individual organs and the highest values were recorded at the first time compared to the third. Moreover, in both transplanting times the highest phosphorus concentration was detected in pods and seeds. As for crop method, the “organic” management caused the highest phosphorus concentration both in the entire plant and in the flowers, in comparison to the conventional method; conversely, a higher phosphorus concentration was found in plant pods obtained under conventional management.
Pods phosphorus concentration was higher in open field than in greenhouse, while the opposite trend was recorded for the flowers. Finally, the “organic” crop management resulted in flowers with higher phosphorus values compared to the same organs obtained under conventional method; opposite results were found for the pods and seeds.
Leaves phosphorus concentration attained the highest values during vegetative stage and flowering, whereas the lowest level was recorded at full fruiting. The shoot accumulation with this element decreased from the vegetative phase to early fruiting, while the roots phosphorus concentration showed a decrease at fruiting. The pods showed the highest phosphorus concentration at full fruiting, where the seeds accumulated increasing amounts from full fruiting to harvest end. The whole plant concentration of this nutrient increased up to full fruiting, thereafter decreased up to crop cycle latest stage.
The dry matter values recorded in open field were significantly higher than those detected in protected environment, while there were no significant differences between the two contexts with regard to the leaf surface. The crops grown in open field showed a greater root expansion in comparison to those grown in protected environment.
The fourth transplanting resulted in the highest dry matter values of the aboveground apparatus, although in protected environment it was not different from the third one, whereas the second transplanting time showed a higher LAI value. The highest dry weight of plant roots corresponded to the fourth transplanting time, while the root apparatus was most expanded with the three intermediate crop cycles. There were no growth significant differences between the plants grown under conventional regime and those cultivated “organically”, referring both to aerial and to underground apparatus. The relation between root and leaf area decreased with the crop phenological development. The roots dry matter was not affected by crop method.
The fourth transplanting showed the highest fresh pods marketable yield in open field, whereas in the greenhouse the highest production was provided by the second, third and fourth transplant, due to the greater number of pods per plant. The production in the open field was significantly higher than that obtained in the protected environment in the third and fourth crop cycle, but the trend was reversed for the second and the fifth transplanting time. In addition, seed yield recorded in the greenhouse crops was significantly higher than that in the open field at the third, fourth and fifth transplanting times and these three plantings resulted in the highest values in both environments. There weren’t, however, any significant differences between the cultural methods, both for pods and seed yield. The pods average weight reached a higher value in open field than in protected only at the fourth transplanting time, while in both environments the first crop cycle got lighter pods. In greenhouse the seeds average weight was higher, regardless of the crop method, and moreover in greenhouse the organic method had a better effect than the conventional one, while in open field there were no significant differences between the two management methods.
Seeds fiber content showed higher values in greenhouse compared to open field and it gradually increased from the first to the fifth transplanting time; no significant differences were found between the management “organic” that conventional. Moreover, seeds fibre percentage increased from 18.1% in the earliest harvested pods to 26.6% in the latest fruits.
Seeds protein percentage recorded in open field was higher than that detected in the greenhouse (30.2 vs 28.2%, respectively). Proteins values gradually increased with the transplanting progress. Proteins percentage showed an increasing trend between the first and last fruit seeds (26.3 to 32.5%).
Seeds polyphenol content attained higher values in open field grown plants than in those managed in greenhouse (29.0 vs 24.5%). Polyphenols concentration was higher under the first two transplanting times (30.5% on average). The effect of “organic” method did not differ from the conventional one on fababean seeds polyphenolic content. Seeds polyphenols concentration showed a 56.9% reduction between the second half of March and the end of April
L’integrazione europea in crisi? Riflessioni sul tema
No full textIs the European Union experiencing a crysis? Is the Covid 19 pandemic showing that the EU is not capable of offering remedies at the European level that single Member States would not be in the position of putting in place? The author shows that this is not the case and that, on the contrary, the emergency which the Covidi 19 originated is oprning new opportunities for the European Union to show to what an extent Member States ald their chitizens need even mor now a coordinated and proactive Europe
Effect of Different Foliar Fertilizer Applications on Esca Disease of Grapevine: Symptom Expression and Nutrient Content in the Leaf and Composition of the Berry
No full textEsca disease, the most common grapevine wood disease in Europe, causes yield losses correlated with the foliar symptoms’ expression. In two vineyards located in the Abruzzo Region of Italy, each of which were investigated for esca symptoms after 1994, different applications of macro- and microelements were performed in two consecutive growing seasons. The main aim of the work consisted of verifying the effects of the fertilizer applications on the foliar symptoms’ expression, in order to deepen knowledge of the nature of the symptom, which is still unclear. For each treatment, in each year, the leaf content of macro- and microelements and the composition of berries and musts were assessed. The effects of these applications on vegetative growth and yield quantity were also verified. The trials were carried out on symptomatic, asymptomatic and
apparently healthy vines. All applications, in particular those with microelements, increased the foliar symptoms’ expression, and a greater vegetative growth was detected only in vines treated with NPK fertilizers. The symptoms’ increase was always associated in the leaf with a decrease of calcium, and to a lesser extent, magnesium, reinforcing the hypothesis of the plant’s hypersensitive reaction in the development of foliar symptoms, given the role of calcium in the defense response. The vineyards were in nutritional balance regardless of the fertilizer applications. The general increase in foliar symptoms and the decrease in sugars in the musts of asymptomatic treated vines underlined the importance of the vegetative-productive balance, in Esca infected vineyards especially, in order to limit the symptoms’ expression and the decrease in yield
Use of near-infrared spectroscopy combined with chemometrics for authentication and traceability of intact lemon fruits
No full textThe reflectance NIR spectroscopy and chemometric data treatment on mature intact lemons, Limone di Sorrento PGI (cv Ovale di Sorrento) and Limone Costa D'Amalfi PGI (cv Sfusato Amalfitano) from Campania region, collected in 2018 and 2019, were used to predict properties, and discriminate cultivar and geographical provenance. By PCA, lemon NIR spectra grouped for production years due to the year variation of lemon properties attributable to annual climatic differences, homogeneous in all sites. This agrees with lemon chemical and physical differences by production year. Consequently, the relationship of NIR spectra with lemon quality properties by MLR and the cultivar and provenances discrimination by LDA were affected by year climatic difference; therefore, better model reliability was for single production year. NIR detectability of lemon properties did not appear beyond lemon thick peels, therefore the measured properties of lemon juices could derive from measurable properties of peel correlating with pulp properties
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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