Intelligent estimation of spatially distributed soil physical properties

Spatial analysis of soil samples is often times not possible when measurements are limited in number or clustered. To obviate potential problems, we propose a new approach based on the self-organizing map (SOM) technique. This approach exploits underlying nonlinear relation of the steady-state geomorphic concave–convex nature of hillslopes (from hilltop to bottom of the valley) to spatially limited soil textural data. The topographic features are extracted from Shuttle Radar Topographic Mission elevation data; whereas soil textural (clay, silt, and sand) and hydraulic data were collected in 29 spatially random locations (50 to 75 cm depth). In contrast to traditional principal component analysis, the SOM identifies relations among relief features, such as, slope, horizontal curvature and vertical curvature. Stochastic cross-validation indicates that the SOM is unbiased and provides a way to measure the magnitude of prediction uncertainty for all variables. The SOM cross-component plots of the soil texture reveals higher clay proportions at concave areas with convergent hydrological flux and lower proportions for convex areas with divergent flux. The sand ratio has an opposite pattern with higher values near the ridge and lower values near the valley. Silt has a trend similar to sand, although less pronounced. The relation between soil texture and concave–convex hillslope features reveals that subsurface weathering and transport is an important process that changed from loss-to-gain at the rectilinear hillslope point. These results illustrate that the SOM can be used to capture and predict nonlinear hillslope relations among relief, soil texture, and hydraulic conductivity data.     

Characterization of the lentil landrace Santo Stefano di Sessanio from Abruzzo,Italy

In the world lentil is grown on more than 3 million hectares and is one of the most important, low-cost, food source of protein. In Italy lentil has been cultivated since ancient times, but in the last decades its cultivation has been confined to marginal areas, small islands and hilly, mountainous areas of central and southern Italy. Local varieties are still common and are often greatly appreciated for their taste and cooking qualities. Several accessions from the Santo Stefano di Sessanio area, Abruzzo Region, were collected and phenotypically and genotypically characterized in order to look for the existing variability within and between populations. Image analysis of seeds was also used. Populations grown in Santo Stefano di Sessanio and in the neighbouring area basically share most of their characteristics. However, some of the accessions anonymously gathered from the local market were shown to be different from those collected from farmers. The paper reports and discusses how this local product needs be characterized and promoted in order to avoid fraud that could negatively affect the local economy and put valuable, adapted, genetic resources at risk of erosion.     

Antimicrobial and Antimycobacterial Activity of Cyclostellettamine Alkaloids from Sponge Pachychalina sp.

Cyclostellettamines A – F (1 – 6) isolated from the sponge Pachychalina sp. and cyclostellettamines G - I, K and L (7 – 11) obtained by synthesis were evaluated in bioassays of antimicrobial activity against susceptible and antibiotic-resistant Staphylococcus aureus, Pseudomonas aeruginosa and antibiotic-susceptible Escherichia coli and Candida albicans, as well as in antimycobacterial activity against Mycobacterium tuberculosis H37Rv bioassays. The results obtained indicated that cyclostellettamines display different antimicrobial activity depending on the alkyl-chain size, suggesting that, if a mechanism-of action is implied, it is dependent on the distance between the two pyridinium moieties of cyclostellettamines.     

Major factors controlling late Pleistocene to Holocene soil development in the Vesuvius area (southern Italy)

In this paper the role of time and late Pleistocene to middle Holocene climate changes in the Somma‐Vesuvius volcano foothill (southern Italy) is investigated with a multidisciplinary approach. Four volcanic soils inter‐layered between five well‐known and well‐dated primary tephra layers were characterized. Chronological constraints were provided by the pyroclastic layers identified in the field (Pomici di Base, Pomici Verdoline, Agnano Pomici Principali, Mercato and Avellino), ranging between 22 and 3.8 thousand years (ka) before present (BP). These represent products of explosive eruptions of Somma‐Vesuvius and the Phlegrean Fields. Another pyroclastic layer (Agnano Monte Spina) from the Phlegrean Fields was also identified, and other ash layers previously unknown in the Somma‐Vesuvius stratigraphy. These were characterized with SEM‐EDS analyses, and correlated with other eruptions from the Phlegrean Fields (Soccavo 4‐5 and Tufi Biancastri) around 12 and 21 ka BP, respectively, thus resulting in further time constraints for phases of soil development. A detailed characterization of the four pedons integrated morphological, physical, chemical, mineralogical and micromorphological analyses. Soil features were interpreted in terms of dominant genetic processes and environmental conditions. The extent of soil development, assessed with pedogenetic indices and the degree of weathering of primary pumices, was only in part consistent with time‐spans of soil formation, suggesting a more important role of climate than soil age. The different extents of expression of andic properties, pumice weathering and varying clay mineralogy allowed us to relate changes to the main climatic phases that occurred during the late Pleistocene to the mid Holocene.     

Effects of iron-based amendments on soil structure: a lab experiment using soil micromorphology and image analysis of pores

Purpose

Recent trends in soil green and sustainable remediation require an increased attention on environmental effects. The physical consequences of remediation practices on soil structure are very rarely investigated.

Material and methods

A laboratory experiment was carried out by adding iron grit to a sand (S), a silt loam (L), and a clay (C) soil subjected to several wetting-drying cycles. The physical effects of the treatment on soil pore system were identified and quantified combining physical measurements on repacked samples with image analysis of pores on resin-impregnated soil blocks and micromorphological analysis on thin sections.

Results and discussion

A negligible reduction of total porosity (P) resulted in S, and a slight increase was observed in the L and C soils. However, an important impact on soil structure was identified in pore size range >10 μm for the L and C soils, with the formation of new pores related to the differential shrink-swell behavior between soil matrix and added iron grains. Different plasticity of these soils also played a role in planar pore formation.

Conclusions

Effects of the addition of iron grit on soil pore system are strongly dependent on soil physical properties. The performed experiment showed that iron-based amendments can improve soil structure in low-plastic shrink-swell soil increasing porosity in the range of transmission pores (50–500 μm). This study showed the high potential of soil micromorphology and pore image analysis in order to evaluate the environmental impact of soil remediation practices.     

Malignant melanoma in a seagull (Larus fuscus): morphological and immunohistochemical approach

A common seagull (Larus fuscus) was found near the southern coast of Italy by the veterinarians of the local wild animal rescue center. Physical examination of the bird revealed an ulcerated mass involving a majority of the oral cavity; the mass did not allow for normal feeding. After the bird died necropsy was performed and the mass was histologically and immunohistochemically examined. The morphology and the immunoreactivity for Melan-A and S-100 antigens led to a diagnosis of malignant melanoma. This is the first case of malignant melanoma described in a seagull, and herein we compare the characteristics of the present case with malignant melanoma already described in domestic animals.     

Ovicidal activity of seven <Emphasis Type="Italic">Pochonia chlamydosporia</Emphasis> fungal isolates on <Emphasis Type="Italic">Ascaris suum</Emphasis> eggs

The ovicidal effect of the nematophagous fungus Pochonia chlamydosporia on eggs of Ascaris suum was tested under laboratory conditions. A. suum eggs were plated on 2% water–agar with seven fungal isolates (Isol. 5, Isol. 31, Isol. 1, VC1, Isol. 12, Isol. 22 and VC4) and control without fungus. After 5, 7, 10, 14, 15 and 21 days of incubation, approximately 100 eggs were removed from the plates and classified according to the following parameters: type 1, biochemical and physiological effect without morphological damage to the eggshell, type 2, lytic effect with morphological alteration of the eggshell and embryo and type 3, lytic effect with morphological alteration of eggshell and embryo showing hyphal penetration and internal egg colonization. The isolates effectively destroyed A. suum eggs and all types of effects were observed during the experiment. There was no variation in ovicidal capacity (type 3 effect) among the isolates (p > 0.05) throughout the experiment. After 21 days, isolate 5 showed the highest percentages of type 3 effect (58.33%). The results indicated that P. chlamydosporia (Isol. 5, Isol. 31, Isol. 1, VC1, Isol. 12, Isol. 22 and VC4) can destroy A. suum eggs and is, therefore, a potential biological control agent of nematodes.     

Experimentally induced melanin-like pigmentation (thesaurismosis) related to acorn ingestion in Nero Siciliano pigs

In this study, an experimental challenge was carried out by feeding Nero Siciliano pigs with acorn to evoke melanin-like pigmentation and support the hypothesis that it is caused by ingested material. Twelve pigs were studied, 6 fed with acorns and 6 fed commercial feed. At slaughter, all the animals fed on acorns showed black discolouration of almost all lymph nodes. The lymph nodes were normal in size and shape. Histochemical tests performed on tissues allowed us to identify and differentiate the pigment. Immunohistochemical staining for macrophage markers showed macrophages containing a variable amount of melanin-like granules. Our data, and the well-known steps of melanin formation, confirm that swine enzymes could act on phenolic substances found in acorns.