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The goal of this study was to identify and characterize three paleo-horizons along a stratigraphic succession embracing sediments from Paleolithic to historic that has been preserved inside a grotto close to the Tyrrhenian Sea in southern Italy. The studied paleo-horizons date back to the transition period between Pleistocene and Holocene, when swift alternations of cold and warm phases profoundly altered the range dynamics of many organisms, including salmonids like Salmo trutta and, consequently, the behavior of the humans that occupied the grotto. Morphological observations and preliminary analysis were run to assess if the paleo-horizons preserved information of the human modified behavior. Results confirmed that one of the three paleo-horizons (Bud horizon, dating back to 10,300 cal YBP) had a strongly affected anthropic origin as it contains the rests of terrestrial (mammals, birds, and snails) and sea food (Salmo trutta and Patella spp.), and showed a hard compaction acquired via hydroconsolidation., EQA - International Journal of Environmental Quality, Vol 25 (2017): Cultural Landscapes

The organic fraction of soils is critically important to soil health and optimal ecosystem functioning. Traditional analysis of soil organic horizons (O horizons) has been dependent upon laboratory-based instrumentation. Simultaneously, the use of proximal sensors such as portable X-ray fluorescence (PXRF) spectrometry along with visible near infrared diffuse reflectance spectroscopy (VisNIR DRS) has gained popularity for providing rapidly acquired spectral and elemental data useful for soil physicochemical property quantification. However, PXRF and VisNIR DRS have mostly been applied to the assessment of mineral soils. This preliminary study evaluated 136 organic laden soil samples (most aptly described as upland, non-saturated O horizons) using both laboratory based instrumentation (CN analyzer) and proximal sensors to evaluate total carbon (TC) and total nitrogen (TN). Results revealed that combining model outcomes using model fusion improved TC and TN prediction accuracies relative to using an individual instrument (PXRF or VisNIR DRS) or model averaging with improvements in root mean square error (RMSE) on the order of 10–47% and 10–67% for TC and TN, respectively. Partial least squares+random forest (PLS+RF) approaches emerged as the best model for predicting both TC and TN in organic laden soil samples. These results suggest that the strong predictive applications of proximal sensors extensively documented on mineral soils, may show similar promise for determination of a wide number of physicochemical properties on organic soil matrices, yet further exploration with a larger and more diverse dataset is recommended.

Subaqueous soils have to be studied with proper methodologies, according to a pedological approach and considering the key role of animal bioturbation. Morphological and chemical characteristics of submerged soils found in the MPA of "Torre del Cerrano", Adriatic sea (Italy), have been studied in this way, and we conclude that submarine soils of the MPA are important examples of pedogenesis promoted by animals. Soils from the highly protected marine area hosted a major biodiversity than those from the sub- and non-protected areas, while no striking differences in terms of soil physical and chemical characteristics among protected, sub-protected and non-protected areas occurred., EQA - International Journal of Environmental Quality, Vol 19 (2015)

Soil magnetic properties are sensitive indicators of pedogenetic processes. Although many of the processes that increase soil magnetism are well documented, the role of microbial communities and the metabolic characteristics of Fe-reducing bacteria are still largely unknown. For this work, two soils with contrasting magnetic properties were identified in a beech forest on Monte Zuccarello (central Italy). Samples of bulk soil and rhizosphere were obtained from A (0–7 cm), AB (7–16 cm), Bw1 (16–22 cm) and Bw2 (22–29 cm) horizons of both soils, and were analysed for their physicochemical characteristics, the amount of magnetic minerals, and the composition of total and culturable bacterial communities, focusing on siderophore-producing bacteria (SPB). Analyses confirmed that the magnetic soil (MS) have a higher content of maghemite and magnetite association, compared to non-magnetic soil (NMS). Since the formation of maghemite can occur through different processes, we investigated on the possible role of soil bacteria in the formation of this magnetic mineral. As soil maghemite generally contains small amounts of Fe2+, the formation of which has been attributed to the combustion of organic matter, SPB have been isolated and identified. MS samples showed the highest number of SPB (mainly Micrococcaceae, Bacillaceae, and Pseudomonadaceae), suggesting a significant increase in Fe-reducing bacteria. High-throughput sequencing analysis revealed a separation in terms of the total composition of the bacterial community between bulk and rhizosphere of both MS and NMS, dominated by Proteobacteria, Actinobacteria, Acidobacteria, and Verrucomicrobia phyla. Interestingly, Gamma and Delta Proteobacteria, as well as Nitrospirae, were usually more abundant in MS than in NMS, confirming that the MS was predominantly characterized by groups of magnetotactic bacteria and SPB, and potentially contributing to enhance the soil magnetic properties.

This study evaluated soil properties along a small transect in the Apennines chain (central Italy). Using latitude and altitude as surrogates for temperature differences, three locations at different latitudes were selected for the study. At each location, two altitudes were selected (800 and 1000 m). The study was conducted by contrasting chemical and biochemical parameters [microbial biomass-C content, amount of CO2 evolved during basal respiration (ΣCO2–C), and potential enzyme activities] of topsoils (O and A horizons) supporting European beech (Fagus sylvatica L.) forests at different scales of investigation: horizons, altitude, and latitude. Along the topsoil, the trend of all investigated properties was unique to each O and A horizon according to its level of organic matter degradation, availability of substrates, and nutrients. Contrasting the altitudes, the difference of 1 °C of temperature between 800 and 1000 m significantly affected some of the chemical parameters and both microbial and enzyme activities mainly in the mineral horizons, although glucuronidase and phosphodiesterase activities appeared to be mainly controlled by TOC content. Generally, the different enzyme activities were more clearly highlighted when they were expressed per organic C unit, rather than on a soil mass basis. Latitudinal sensitivity was recorded for total N, ΣCO2–C, and some enzyme activities, although no difference in mean annual air temperature occurred along the latitudinal transect. In this case, it is plausible that the summer-winter thermal excursion, which was lower for the southernmost location and increased going north, might have indirectly affected these parameters through changes in the plant-soil relationships, composition of the macro- and mesofauna population, and microbial activity. Considering all the investigated aspects, an increase of 1 °C in mean annual air temperature (in the range 9–10 °C) and/or the alteration of summer-winter thermal excursion might affect the actual soil-plant balance in temperate beech forests, with possible greater mineralization of the topsoil organic matter and a major release of CO2 in the atmosphere.

Climate warming is predicted to raise the mean global temperature by 1 °C in the next 50 years, and this change is believed to be capable of affecting soil organic matter cycling and nutrient availability. With the aim of increasing knowledge on the response of forest soils to the ongoing climate change, we used altitude as a proxy for temperature change and studied chemical and biochemical properties of European beech (Fagus sylvatica L.) forest soils at two altitudes (800 and 1000 m) from central Apennines (Italy). Results showed that 1 °C of mean annual air temperature difference between the sites at the two altitudes had greater effect on the mineral horizons than on the organic horizons. At higher altitude, mineral soil had limited development, higher pH, and higher organic matter content due to the lower efficiency of the microbial community. Enzymatic activities of the organic horizons were generally not affected by altitude. Conversely, we observed a higher activity of xylosidase, β-glucosidase, alkaline phosphomonoesterase, arylsulfatase, and leucine-aminopeptidase in the sub-superficial horizons (Bw1 and Bw2) of the soils at 1000 m. We hypothesized that, as a response to environmental and climatic constraints occurring at higher altitude, plant roots increase the production of enzymes directly and/or indirectly by triggering the microbial community through exudation.