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We evaluated the influence of the rhizosphere, soil depth, and altitude on the amount and nature of the density separated soil organic matter (SOM) pools. Samples were collected from the A and AB horizons of European beech (Fagus sylvatica L.) forest soils located at two altitudes (800 and 1000 m) along 1° of latitudinal gradient in central Italy, by using altitude as a proxy for air temperature change. Specifically, we hypothesized that: i) larger amount of labile organic matter, comprising of fresh plant and organism residues and easily degradable molecules, was allocated in the rhizosphere than in the non-rhizosphere soil, and ii) the temperature had a stronger effect on the C pools of the rhizosphere than in that of the non-rhizosphere soil. At both altitudes, we found more organic C (OC) associated with the light fractions of the rhizosphere than in those of the non-rhizosphere soil and, specifically in the rhizosphere free light fraction, larger OC concentrations were observed at 1000 m than at 800 m above sea level. These higher amounts of OC have been attributed to roots, which are one of the main source of particulate organic matter, and their activity and turnover increase when the environmental conditions become more restrictive, as it happens at higher altitude. Conversely, no effect related to rhizosphere and altitude on the OC associated to the heavy fraction was found. The recalcitrance of the OC of the heavy fraction has been ascribed both to its protection due to the tight bounds to mineral particles and to its degradation degree, as indicated by δ 13C values, which were greater than those of the light fractions. The similar 14C signature and the presence of recent C in all the density fractions of rhizosphere and non-rhizosphere soil of both A and AB horizons suggested the occurrence of a rapid incorporation of fresh organic matter into the mineral horizons, followed by occlusion into aggregates and adsorption on mineral surfaces. Further, the lack of different Δ14C values between the fractions at 800 and 1000 m could indicate that a temperature change of 1 °C is not sufficient to induce marked changes in SOM cycling. • The effect of beech rhizosphere and altitude on soil organic C pools was evaluated. • Organic C of the light fractions was affected by both rhizosphere and altitude. • Organic C of the heavy fraction had low sensitivity to rhizosphere and climate effects. • Δ14C values of OC pools showed a rapid incorporation of litter floor into mineral soil. • 1 °C warmer temperature is ineffective on the stabilised organic C pool. [ABSTRACT FROM AUTHOR]

• Climate changes and geomorphic processes drove soil formation in southern Tunisia. • Soil accretion and deflation were the main pedogenetic processes. • Byy horizons formed from accretion of windblown materials and salt-rich water-table. • Hardpan formed from sedimentation of repeated mudflows. • Bk horizons formed from cycles of sedimentation and strong wind erosion. Arid environments are fragile and the associated soils are subject to serious threats like water deficiency, erosion, salt accumulation, and loss of fertility. In this context, understanding the processes involved in soil genesis may contribute toward protecting land from degradation. This study highlights the interconnection between geomorphic and pedogenetic processes in soil formation of the Jeffara Plain, a pre-Saharan area of southern Tunisia. To reach this goal, one coastal oasis (Chenini Nahel) and two inland environments (Matmata Nouvelle and Menzel Habib) were studied. After geomorphological and pedological surveys, the soils were sampled by genetic horizons and characterized by physical, mineralogical, and chemical analyses, and by microscope observation. Field observations and laboratory data suggest that soil formation in the Jeffara Plain was a combination of additions and losses controlled by climate changes. At Chenini Nahel, the soils developed by accumulation of wind-blown sediments coming from a close area dominated by gypsum-bearing rocks. At Matmata Nouvelle, the soils mainly formed from sedimentation of repeated mudflows during a rainy period between 9000 and 5000 years before present, followed by drought periods. Finally, the soils of Menzel Habib developed from an early gypsum formation in the presence of a salt-rich water table and repeated cycles of sedimentation/deflation of wind-blown materials. The different genesis of these pre-desert soils produced characteristic B horizons: Byy horizons with poorly developed soil structure at Chenini Nahel, Bw horizons with a hard rupture-resistance at Matmata Nouvelle, and Bk horizons at depth due to intense sedimentation with CA + BC horizons at the surface due to the accretion of wind-blown materials at Menzel Habib. [ABSTRACT FROM AUTHOR]

There is a great global concern about agricultural wastes from food and feed crop processing that have significant environmental impacts. Composting is the most environmentally friendly, cost-effective, and efficient processes that can solve the problems of accumulation and toxicity of agricultural waste. The aim of this study is the detoxification of coffee husk by composting at two temperature conditions ("warm" and "cold"). In the greenhouse, the ambient temperature was changed day by day to mimic the situation of a spring to summer "warm" period (≈16-34 °C) and a spring "cold" period (≈7-20 °C) typical of central Italy. The coffee industry should accept the responsibility for the large amount of organic waste production, which presents toxicity and mass accumulation problems. Coffee husk as the main raw material is not used directly as bio-fertilizer in agriculture sector due to the leaching of phenolic compounds and high pH value. The brewing industry is famous for its mass production, and the brewer residues as a by-product have an extremely acidic pH that makes them an unsuitable material for direct composting, but the mixture of these materials can optimize pH. The addition of cow manure accelerates microbial activity and is a strategy to improve composting rate and maturity. The following mixtures were tested: coffee husk and brewer spent grains in a proportion of 2:1 (Compost 1), coffee husk and cow manure in a proportion of 4:1 (Compost 2), and coffee husk, brewer spent grain, and cow manure in a proportion of 5:3:2 (Compost 3). Quality and maturity of the final composts appeared to be affected by the ambient temperature conditions, which remarkably affected pH, C/N ratio, nutrient and trace elements availability, germination index, microbial biomass carbon, and FDA hydrolysis. Results showed that both sets of temperatures produced composts to be considered standard compost, but "warm" conditions compost showed greater maturity, while the composts produced under "cold" conditions were able to increase seed gemination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Composting mitigates environmental risks associated with using solid digestate as fertilizer. However, evidence is lacking on benefits of using composted digestate as fertilizer in enhancing soil health and increasing agronomic yield compared to non-composted digestate (hereafter, digestate). A field study was conducted consisting of digestate, composted digestate, co-composted digestate with biogas feedstocks (corn [Zea mays L.] silage, poultry litter, corn silage + poultry litter or food processing by-product), inorganic nitrogen fertilizer, and control (no treatment applied) on soil microbial biomass, enzyme activities (EA), soil organic carbon (SOC), bioavailable P (P), total nitrogen (TN), soil health index (SHI), and sunflower (Helianthus annuus L.) yield. The Partial Least Square Path Model (PLS-PM) was used to predict: 1) nutrient cycling in response to changes in microbial growth and EA and 2) agronomic yield in response to SHI and soil nutrients dynamics. Composted digestate had equivalent soil health benefits with most of co-composted materials and digestate, albeit agronomic yield was greatest with composted digestate, which was 40 % and 100 % greater than with inorganic nitrogen fertilizer and digestate, respectively, indicating composted digestate's potential to replace the synthetic N fertilizer. Moreover, composts from a sole digestate, rather than the ones from co-composted with fresh feedsstocks, can be promising organic amendments and fertilizers for growing sunflower. The PLS-PM model identified that triggered microbial biomass growth and EA, following digestate and composted digestate applications, catalyzed organic matter decomposition, resulting in enhanced nutrients contents and soil health. However, the model revealed that improved SHI did not predict agronomic yield, as opposed to P and TN, suggesting agronomic performance may have been more sensitive to changes in specific soil nutrients status than the overall soil health condition. We conclude that the benefits of composted digestate as fertilizer hint the significance of digestate valorization via post-digestate composting and compost utilization for sustainability of the bioenergy sector., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In forest ecosystems, soil-plant interactions drive the physical, chemical, and biological soil properties and, through soil organic matter cycling, control the dynamics of nutrient cycles. Parent material also plays a fundamental role in determining soil's chemical properties and nutrient availability. In this study, eight long-time coppice-managed Holm oak forests under conversion to high forest, located under similar climatic conditions in Tuscany and Sardinia Regions (Italy), and grown on soils developed from three different lithologies (limestone, biotite granite, and granite with quartz veins) were evaluated. The research aimed to a) estimate the amount of C and nutrients (total N and potentially available P, Ca, Mg, and K) stored both in the organic, organo-mineral, and mineral horizons and at fixed depth intervals (0-0.3 and 0.3-0.5 m), and b) assess the dominant pedological variables driving elemental accumulation. The soils were described and sampled by genetic horizons and each sample was analyzed for its C and nutrient concentration in both the fine earth and skeleton fractions. Despite the different parent materials from which the soils had evolved, the physicochemical properties and the C and nutrient stocks for the 0-0.3 and 0.3-0.5 m layers did not show substantial differences among the eight soils. Conversely, some differences were observed in the stocks of potentially available P and Ca per 0.01 m of mineral horizons. The findings show that over time, plant-induced pedogenic processes (acidification, mineral weathering, organic matter addition, and nutrient cycling) almost obliterated the influence of parent materials on soil properties. This resulted in the upper soil horizons that showed similar characteristics, even though derived from different lithologies. However, among the study sites, some differences occurred due to lithology, as in the case of the soils derived from calcareous parent materials that had high concentrations of exchangeable Ca in the mineral horizons and, likely, to environmental variables (e.g., exposure), which possibly influenced litter degradation and the release of nutrients such as N and available P., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Slash and burn is a land use practice widespread all over the world, and nowadays it is formally recognized as the principal livelihood system in rural areas of South America, Asia, and Africa. The practice consists of a land rotation where users cut native or secondary forest to establish a new crop field and, in some cases, build charcoal kilns with the cut wood to produce charcoal. Due to several socio-economic changes in developing countries, some scientists and international organizations have questioned the sustainability of slash and burn since in some cases, crop yield does not justify the soil degradation caused. To estimate the soil quality in agricultural and forest soils at different ages of the forest-fallow period (25, 35, and 50 years), this survey investigated rural areas in three locations in Manica province, central Mozambique: Vanduzi, Sussundenga, and Macate. Soil profiles were trenched and sampled with a pedological approach under crop fields and forest-fallow. The chronosequence was selected to test the hypothesis that the increase in forest-fallow age causes an improvement of soil fertility. Results highlighted discrete variations among locations in mineralogy, Al- and Fe-oxyhydroxides, sand, silt, pH, total organic carbon, humic carbon, total nitrogen, available phosphorous, chloride, nitrate, fluoride, and ammonium. Few differences in mineralogy, Fe-oxyhydroxides, available P, chloride, and nitrate were detected between crop fields and forest-fallow within the same location. Such differences were mostly ascribed to intrinsic fertility inherited from the parent material rather than a longer forest-fallow period. However, physicochemical soil property improvement did not occur under a forest age of 50 years (the longest forest-fallow considered), indicating that harmonization of intrinsic fertility and agronomic practices may increase soil organic matter and nutrient contents more than a long forest-fallow period., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Urban soils are often mixed with extraneous materials and show a high spatial variability that determine great differences from their agricultural or natural counterparts. The soils of 18 localities of a medium-sized city (Ancona, Italy) were analysed for their main physicochemical and biological properties, and for chromium (Cr), copper (Cu), cobalt (Co), lead (Pb), nickel (Ni), zinc (Zn), and mercury (Hg) total content, distribution among particle-size fractions, and extractability. Because of the absence of thresholds defining a hot spot for heavy metal pollution in urban soils, we defined a "threshold of attention" (ToA) for each heavy metal aiming to bring out hot spot soils where it is more impellent to intervene to mitigate or avoid potential environmental concerns. In several city locations, the soil displayed sub-alkaline pH, large contents of clay-size particles, and higher TOC, total N, and available P with respect to the surrounding rural areas, joined with high contents of total heavy metals, but low availability. The C biomass, basal respiration, qCO 2 , and enzyme activities were compared to that detected in the near rural soils, and results suggested that heavy metals content has not substantially compromised the soil ecological services. We conclude that ToA can be considered as a valuable tool to highlight soil hot spots especially for cities with a long material history and, for a proper risk assessment in urban soils, we suggest considering the content of available heavy metals (rather than the total content) and soil functions., (© 2021. The Author(s).)

In forest ecosystems, a variety of abiotic and biotic soil forming factors drives soil organic matter (SOM) and nutrients cycling with a profitable outcome on climate change mitigation. As a consequence, type and intensity of forest management, through its impact on carbon (C) and nutrient soil stocks, can be considered as an additional soil forming force. In this study, we investigated the influence of the coppice conversion into high forest on pedogenesis and on soil C and nutrient (N, P, Ca, Mg, and K) stocks, fifty years later the beginning of the conversion-cycle. The trial was established in a Turkey oak forest historically managed under the coppice system in central Italy. Specifically, we considered tree population density (natural evolution - control, moderate thinning, heavy thinning) where soil samples were collected according to genetic horizon to estimate C, N, and P stocks both in the forest floor and at fixed depth intervals (0-30, 30-50 and 50-75 cm). Further, the stocks of exchangeable Ca, Mg, and K were also assessed for the mineral layers. The results showed that litter and the upper layer of mineral soil (0-30 cm) contained a similar quantity of C (about 74-83 Mg ha -1 ), independently of the trials and no differences were observed also in the whole soil stocks (about 192-213 Mg ha -1 ). The comparison of the mean stocks calculated per 1-cm of thickness of organic (O), organo-mineral (OM), and mineral (M) layers, although it did not display any difference among trials (excepted for P and Mg), showed a similar capability of the organo-mineral horizons to store C and nutrients compared with the organic ones (e.g., about 6-12 Mg ha -1 , 0.3-0.5 Mg ha -1 and 0.5-1.5 kg ha -1 for C, N and P, respectively). Our findings showed that thinning operated on Turkey oak coppice did not affect soil capacity to store C and nutrients. These results suggested that the forest ecosystem itself is the main soil forming force and this is consistent with the target of adopting forest management able to control the global C cycle through the storage of SOM in the mineral soil rather than in forest floor, where SOM turnover is faster., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The current study evaluated the quality of agricultural waste digestate by composting or co-composting with biogas feedstock (maize silage, food processing waste, or poultry litter). Temperature, phytotoxicity, C/N ratio, water extractable trace elements, and 14 enzyme activities were monitored. Temperature dropped earlier in digestate and maize silage co-composting pile, reducing time to maturity by 20 days. Composting and co-composting reduced phytotoxicity and C/N ratio, but increased immobilization of Al, Ba, Fe, Zn, and Mn at least by 40% in all piles. All the enzyme activities, except arylsulfatase and α-glucosidase, increased at the maturity phase and negatively correlated with organic matter content and most of trace elements. Post-digestate composting or co-composting with biogas feedstock is a promising strategy to improve digestate quality for fertilizer use, and selected enzyme activities can be indicators of compost maturity and immobilization of trace elements., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This review was aimed to summarize and critically evaluate studies on removal of veterinary antibiotics (VAs), antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) with anaerobic digestion (AD) of manure and demonstrate areas of focus for improved removal efficiency. The environmental risks associated to the release of the same were also critically evaluated. The potential of AD and advanced AD of manure on removal rate of VAs, ARGs and MGEs was thoroughly assessed. In addition, the role of post and pre-AD treatments and their potential to support VAs and ARGs removal efficiency were evaluated. The overall review results show disparity among the different groups of VAs in terms of removal rate with relatively higher efficiency for β-lactams and tetracyclines compared to the other groups. Some of sulfonamides, fluoroquinolones and macrolides were reported to be highly persistent with removal rates as low as zero. Within group differences were also reported in many literatures. Moreover, removal of ARGs and MGEs by AD was widely reported although complete removal was hardly possible. Even in rare scenarios, some AD conditions were reported to increase copies of specific groups of the genes. Temperature pretreatments and temperature phased advanced AD were also reported to improve removal efficiency of VAs while contributing to increased biogas production. Moreover, a few studies also showed the possibility of further removal by post-AD treatments such as liquid-solid separation, drying and composting. In conclusion, the various studies revealed that AD in its current technological level is not a guarantee for complete removal of VAs, ARGs and MGEs from manure. Consequently, their possible release to the soils with digestate could threaten the healthcare and disturb soil microbial ecology. Thus, intensive management strategies need to be designed to increase removal efficiency at the different manure management points along the anaerobic digestion process., (Copyright © 2020 Elsevier B.V. All rights reserved.)

We report data on the physicochemical properties of soils collected in two adjacent areas, one acid and one sub-alkaline, both developed on sequential beds of Plio-pleistocene marine sediments, and on the chemical composition of ecological solutions (rainfall, throughfall and stemflow) separately collected in the two areas. Throughfall and stemflow were generated by Turkey oak trees ( Quercus cerris L.), which was the dominant tree species in both study areas. These data are related to the original article "Soil affects throughfall and stemflow under Turkey oak ( Quercus cerris L.)" (Corti et al., 2019) [1].