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Human activities cause modifications of the soil characteristics, leading to a significant reduction of the soil fertil- ity and quality. The aim of this study was to evaluate the relationships between microbial activity or biomass and chemical char- acteristics (i.e. heavy metal and organic matter contents) of a degraded urban soil. The study area is located in an urban park (about 10 ha, called Quarantena) near to the Fusaro Lake of Campi Fle- grei (Southern Italy); the Park was established in 1953 to shelter animals coming from any place of the Planet and execute veterinary checks before their delivery to different European zoos. In 1997, the park was abandoned and nowadays in it a large amount of urban wastes accumulates. Surface soils (0-10 cm) were sampled at three points: two of them covered by Holm Oak specimens (P1 and P2) and one covered by herbaceous species, particularly legumes (P3). P1 was localized at the border of the park and next to a busy road; P2 at the centre of the Quarantena Park; P3 at a gap area near the Fusaro Lake. The results showed that the soil sampled at P1 showed the highest Cr and Ni concentrations; the soil sampled at P3 had high levels of Cu and Pb, exceeding the threshold values of 100 μg g-1 d.w. fixed by the Italian law for urban soils, probably due to boat traffic, fishing practice and agricultural activities; the soil sampled at P2 had interme- diate values of metal concentrations but the highest amount of organic matter (more than 20% d.w.). Despite of metal contamination, P1 and P3 showed higher soil microbial biomass and activity as compared to P2. Therefore, at this site, the organic matter accumulation could be due to the scarce litter degradation. In conclusion, although the studied area was not too large, a wide heterogeneity of soil quality (in terms of the investigated chemical and biological characteristics) was detected, depending on the local human impact.

Soil is a prime component of terrestrial areas that provides many services that guarantee the functionality of the ecosystems, support organism life, sustain plant or crop productivity, regulate gas exchanges between atmosphere and biosphere, allow organism wellness and maintain the environmental quality. In the last century, human density rapidly increased, causing strong environmental variations to satisfy their needs and leading to an excessive land transformation. Land use changes determine deep alterations of ecosystem functionality that governs physical, chemical and microbiological processes. As soil formation is slower than its consumption,it is necessary to preserve soil quality in order to sustain environment health. Because soil functions are difficult to measure, soil properties that are sensitive to specific changes can be used as indicators of soil quality. The present research provides a contribution to the actual knowledge on the characteristics of soils affected by environmental degradation due to intensive or extensive use of lands by humans (quarries, agriculture,urbanization) and by management of a natural reserve. The overall aim of the research was to evaluate the quality of soils undergone to different kinds of anthropic impacts. Particularly, the research aimed: i) to exam the feasibility to recover quarries through the single addition of organic amendments; ii) to evaluate the chemical, biological characteristics of agricultural soils inside an urban fabric and of forest soils inside a National Park. Besides, the studies were also focused on the relationships between the chemical characteristics of the soils and the biota and a minimum data set of indicators was proposed in order to provide a useful tool to decision-makers to monitor, conserve or improve soil quality. The main results of the research focused on quarry recover through a single application of the investigated organic amendments (compost and a mixture of compost and poultry manure) highlighted an improvement of the substrate properties, as, over the time, the metal availabilities decrease and microbial community increase. The agricultural soils inside the urban fabric and the soils of the Vesuvius National Park appeared slightly contaminated by Cu e Pb, nevertheless, soil microbial biomass were scarcely affected by their concentrations. In addition, only four indicators, selected from twenty-five parameters, appeared enough to monitor the quality of soils inside the Vesuvius National Park.

Plastic sheets are widely used in farming soil to improve the productivity of cultures. Due to their absorption capacity, plastic sheets can alter element and metal content in soils, and in turn affect soil properties. The use of biodegradable films is an attractive eco-sustainable alternative approach to overcome the environmental pollution problems due to the use of plastic films but their impacts on soil are scarcely studied. The aim of the research was to evaluate the impact of conventional plastic and bioplastic sheets on total and available concentrations of elements (Al, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) in soils. The research was performed in mesocosm trials, filled with soil covered by conventional plastic and bioplastic sheets. After six months of exposure, soils were characterized for pH, water content, concentrations of organic and total carbon and total nitrogen, and total and available Al, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn element concentrations. The results highlighted that soils covered by bioplastic sheets showed higher total and available concentrations of elements and higher contamination factors, suggesting that bioplastic sheets represented a source of metals or a less-effective sink to these background metals in soils, compared to conventional plastic ones.

The knowledge of the effects of fire on soil properties is of particular concern in Mediterranean areas, where the effects of vegetation type are still scarce also. This research aimed: to assess the properties of burnt soils under different vegetation types; to highlight the soil abiotic properties driving the soil microbial biomass and activity under each vegetation type; to compare the biological response in unburnt and burnt soils under the same vegetation type, and between unburnt and burnt soils under different vegetation types. The soils were collected at a Mediterranean area where a large wildfire caused a 50% loss of the previous vegetation types (holm oak: HO, pine: P, black locust: BL, and herbs: H), and were characterized by abiotic (pH, water, and organic matter contents; N concentrations; and C/N ratios) and biotic (microbial and fungal biomasses, microbial respiration, soil metabolic quotient, and hydrolase and dehydrogenase activities) properties. The biological response was evaluated by the Integrative Biological Responses (IBR) index. Before the fire, organic matter and N contents were significantly higher in P than H soils. After the fire, significant increases of pH, organic matter, C/N ratio, microbial biomass and respiration, and hydrolase and dehydrogenase activities were observed in all the soils, especially under HO. In conclusion, the post-fire soil conditions were less favorable for microorganisms, as the IBR index decreased when compared to the pre-fire conditions.

Altitude, exposure, and plant cover may have a significant impact on the soil system, affecting its abiotic characteristics and, in turn, soil microbial composition and activity. In the Mediterranean area, the relationships among environmental features and soil characteristics are still scarcely investigated. The present study aimed to evaluate the effects of altitude, slope exposure, and plant cover on soil abiotic characteristics and the responses of the soil microbial community. Surface soil was sampled at 32 field points of the Vesuvius Mountain (Southern Italy) at two slope exposures (North and South), two altitudes (600 and 900 m a.s.l), and under two different plant covers (pines and shrubs), and it was analyzed for soil abiotic and biotic characteristics. The results showed that soil characteristics mainly differed according to site altitude, but some characteristics also changed according to site exposure and plant cover. The soil organic carbon (Corg) showed significant high values at low altitude, south exposure, and under pines and played a role in influencing the soil microbial community. In soil covered by pines, the greatest soil Corg amount matched with the highest values of C/N ratio and fungal biomass. Finally, high Corg and water availability significantly enhanced the microbial activities.

Plant-based products comprise the vast majority of human and animal nutrition, and metal concentration and accumulation inside food can affect human health. Recently, agricultural soils are often located in close proximity of urban fabrics and factories, so that risk of contamination is high. A field study, carried out in summer 2014, aimed to: i) evaluate the chemical, biological and ecotoxicological characteristics of an agricultural soil in the neighbourhood of the city of Naples (Southern Italy); ii) detect Cd, Cr, Cu, Ni and Pb concentrations and accumulations in roots of sunflower and sorghum; iii) distinguish the potential main pathway (by roots or leaves) of metal uptake in the two crop species. Metal concentrations were measured in soil, roots, stems, leaves and seeds. Besides, the metal bioaccumulation and translocation factors were also calculated. Soils resulted slightly contaminated by Cu and Pb, deriving by both agricultural practices and urban inputs, but did not differ in biological and ecotoxicological characteristics. Cu was the most abundant metal and roots appeared the main path of metal uptake for both the crop species. In sunflower, roots apparently limit the absorption of Pb as well Cu and Cd uptake by leaves from the atmosphere cannot be excluded. Sunflower, likely for the higher biomass and faster growth rate as compared to sorghum, showed an overall higher metal accumulation, particularly high for Cd and Cu in the seeds. Capsule Sorghum and sunflower, grown in an agricultural field inside an urban fabric, showed a different metal compartmentalization and accumulation in biomass portions used in human dietary