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Forest soils harbour a vast array of organisms that govern the processing of organic matter. Through their trophic interactions, they give rise to carbon flows that sustain soil ecosystem functioning. Understanding how soil food webs shape carbon flows may enhance our knowledge about the role of biodiversity on soil processes. In this work, we assembled trophic networks representing soil food webs of two beech forests during spring and autumn, and compiled mass-balanced models quantifying carbon flows between their components. These models were investigated using network analysis to identify the role of the components on carbon flow, cycling and functional trophic relationships. Moreover, we explored how the structure of carbon exchanges promote efficiency and stability. Results indicate the importance of indirect interactions. Most trophic groups exhibit a diffuse dependency on all the compartments for their carbon requirement although certain groups such as Collembola play the role of hubs in distributing carbon. Indirect interactions often reverse the impacts of direct trophic relationships being antagonistic to the direction of change predicted based on predator–prey interactions. The high incidence of generalist feeding habits increases the redundancy of energy channels thereby making such food webs more resilient against perturbations but at the expense of carbon transfer efficiency. Although differences can be observed across sites and periods, food web structure rather than environmental variability seems to be the main factor responsible for patterns of carbon flows in the two beech forests. Read the free Plain Language Summary for this article on the Journal blog.

Under the increasing global energy demand, the new European Union Biodiversity Strategy for 2030 encourages combinations of energy production systems compatible with biodiversity conservation; however, in photovoltaic parks, panels shadowing the effects on soil health and biodiversity are still unknown. This study (location: Northern Italy) aimed to evaluate the effect of ground-mounted photovoltaic (GMPV) systems on soil arthropod biodiversity, considering two parks with different vegetation management: site 1—grassland mowed with tractor; site 2—grassland managed with sheep and donkeys. Three conditions were identified in each park: under photovoltaic panel (row), between the panel rows (inter-row), and around the photovoltaic plant (control). The soil pH and organic matter (SOM), soil arthropod community, biodiversity, and soil quality index (e.g., QBS-ar index) were characterised. Differences between the two GMPVs were mainly driven by the SOM content (higher values where grazing animals were present). No differences were observed in site 1, even if a high heterogeneity of results was observed for the soil biodiversity parameters under the panels. In site 2, SOM and pH, as well as arthropods biodiversity and QBS-ar, showed low values in the row. Soil fauna assemblages were also affected by ground-mounted panels, where Acarina, Collembola, Hymenoptera, and Hemiptera showed the lowest density in the row. This study suggests that ground-mounted solar panels had significant effects on below-ground soil fauna, and was more marked depending on the system management. Furthermore, the results obtained for the inter-row were similar to the control, suggesting that the area between the panel rows could be considered a good hotspot for soil biodiversity.

Bioplastics may be collected in the bio-waste treatment, which is often composed of anaerobic digestion and subsequent aerobic composting of the digestates. The aim of this study was to evaluate the degradability of polylactic acid (PLA) and starch-based bioplastics (SBB) spoons under industrial conditions. Biomethane potential (BMP) was measured and biogas production was monitored, while the quality of composts was assessed by phytotoxicity and ecotoxicity tests. The bioplastics disintegration resulted in 65.1 ± 4.6 % for PLA and ≤ 65.0 ± 7.4 % for SBB, not achieving the target set by UNI EN 13,432 standard, and several residues were found in compost. Phytotoxicity tests on seeds reported the lowest Germination Index for PLA elutriate, whereas a potential negative effect of SBB on soil fauna was detected. Further investigation is needed to assess the fate of these ever-growing materials under industrial conditions, and also evaluate the effects of residues in compost.

PCDD/Fs (polychlorinated dibenzo-p-dioxins/dibenzofurans) and PCBs (polychlorinated biphenyls) are ubiquitous persistent pollutants with reduced bioavailability, which bioremediation using soil fauna is still managed to treat. This research set out to: (i) study the suitability of earthworms (Eisenia fetida), alone and associated with plants (Lepidium sativum), for the decontamination of PCDD/F and PCB polluted soils in Brescia-Caffaro (Italy), at total and congener concentration levels; (ii) simulate the action of earthworms in groundwater contamination process and nutrient mobility. Five treatments were set up: (i) uncontaminated soil with E. fetida (NC); (ii) contaminated soil (C); (iii) contaminated soil with E. fetida (CEf); (iv) contaminated soil with L. sativum (CLs); (v) contaminated soil with E. fetida and L. sativum (CEfLs). PCBs and PCDD/Fs in the soil prior to testing were measured. Analysis was repeated in soil treatments and percolating water at the end of the test period (4 months). Dissolved nutrient concentrations were measured in percolated water. PCB and PCDD/F concentrations, initially 259333.33 ± 10867.89 ng/kg and 176 ± 10.69 ngTE/kg, were significantly reduced after 4 months in all treatments. Treatments did not differ in total PCBs concentration (from 160,000 ng/kg to 194,000 ng/kg), but CEfLs congeners concentrations were less environmentally threatening; CEf and CLs resulted in lower PCDD/Fs concentration (79.43 ± 3.34 ngTE/kg and 73.03 ± 4.09 ngTE/kg, respectively). The action of earthworms could enhance contaminants and soluble reactive phosphorous content in percolating water.

In this study we analysed the diversity of vascular plants, soil microorganisms and microarthropods on two serpentine outcrops in the Northern Apennines (Italy). The soils of the two sites are at different stages of evolution, as shown by soil depth and soil organic matter (SOM) content: the first site is a serpentine grassland clearing within sub-montane vegetation, while the second is a serpentinite scree rich in specialised flora only, including rare hyperaccumulator plant species such as Noccaea caerulescens and Alyssum bertolonii. The aboveground biodiversity was analysed via floristic releves. The bacterial diversity was estimated through 16S rDNA profiling of the Ni hyperaccumulator N. caerulescens at the rhizosphere level, which thrives in both sites. Microarthropod communities were characterized by extracting and identifying organisms from the soil. The number of individuals per taxon, Acari/Collembola ratio, biodiversity indices and QBS-ar index were calculated. The two sites showed a clear difference as regards plant community: only three plant species were present in both sites, namely Euphorbia cyparissias, belonging to Euphorbiaceae, Galium spp., belonging to Rubiaceae, and N. caerulescens, belonging to Brassicaeae. Belowground diversity was positively correlated with vegetation cover and SOM content. In particular, among the bacteria colonising the rhizosphere of N. caerulescens (present in both sites), Actinobacteria, which exhibit K-strategist attributes and are more successful in resource-limited, crowded environments, appeared to be more abundant in the site with lower SOM and higher content of Ni. Bacterioidetes, which are specialised in degradation of cellulose, chitin and plant detritus, were instead more abundant in the site with higher SOM. As for soil microarthropod communities, the site with higher concentration and bioavailability of heavy metals and lower SOM showed poorer and less structured community. In conclusion, the data observed with plant, microbial and microarhropod communities identify different micro-habitats, in spite of proximal geographical position and the common metal-rich substrate.

Forests, including their soils, play an important role since they represent a large reservoir of biodiversity. Current studies show that the diversity of soil fauna provides multiple ecosystem functions and services across biomes. However, anthropogenic practices often pose a threat to soil fauna because of changes in land use and soil mismanagement. In these terms, rangelands in the southwest of Spain present several problems of soil degradation related to livestock activity and soil erosion, the intensity of which compromises the soil fauna&rsquo, s functions in the ecosystem. Therefore, the aim of this study is to evaluate the response of community metrics and the spatial distribution of soil microarthropods to livestock activity and vegetation in such ecosystems. A photo interpretation analysis of an experimental catchment used as a study area was developed to identify and classify the intensity of livestock pressure. A total of 150 soil samples were collected throughout 2018. Soil biological (CO2 efflux) and physical-chemical parameters (pH, bulk density, organic matter, and water contents), and such meteorological variables as precipitation, temperature, and evapotranspiration were considered as variables affecting the composition of microarthropod communities in terms of taxa diversity, abundances, and their adaptation to soil environment (evaluated by QBS-ar index). Results showed higher abundance of microarthropods and higher adaptation to soil environment outside the influence of trees rather than beneath tree canopies. Moreover, the classification of livestock pressure revealed by the photo interpretation analysis showed low correlations with community structure, as well as with the occurrence of well-adapted microarthropod groups that were found less frequently in areas with evidence of intense livestock activity. Furthermore, abundances and adaptations followed different spatial patterns. Due to future climate changes and increasing anthropogenic pressure, it is necessary to continue the study of soil fauna communities to determine their degree of sensitivity to such changes.

In the Parma Functional Urban Area, hydro-geo-ecology was investigated through an interdisciplinary approach, with emphasis on the shallow aquifer system. The study pointed out that domestic wells and fontanili are both fed by shallow groundwater affected by PCE and nitrate contamination, upgradient of the rural area located north of Parma City. Moreover, Folsomia candida tests suggested the possibility that other types of contaminants (not analysed in this study) can affect the shallow groundwater. Nowadays, PCE concentrations in the city centre are slightly higher than the limit set by law. Moreover, PCE aerobic biodegradation can be due to the local microbial community and then an effective natural attenuation can be expected along the groundwater flow pathway. These results suggest a very low risk for human health, linked to the groundwater consumption in the rural area north of Parma City. Conversely, no forecasts can be made at present about the possible impact of low PCE concentrations on the aquatic ecosystem observed at the fontanili. Concerning nitrate contamination, the higher concentrations detected in some wells and fontanili suggest a high risk for both human health and aquatic ecosystems. In a wider context, thanks to the interdisciplinary approach that combines successfully well-established investigation methods, the present study allows a better knowledge of the hydro-geo-ecological behaviour of groundwater-dependent ecosystems. At the same time, through purpose-designed experimental investigations and simulation models, this approach could be used as a sort of guideline useful in studying such complex environmental systems.

International audience; The SETA group (Agricultural Science and Technology) sent a letter to the Italian Parliament advising them not to adopt a legislative measure that favors organic and biodynamic agriculture compared to the conventional one. Another group of scientists thinks instead that the Italian government should favor organic and biodynamic agriculture and explains its reasons. The current article lists the SETA letter and the point of view of other Italian and international ecologists, economists, pedologists, ecologists, writers and artists, which are tendentially “protectors of nature” but not idealists. Nor are they so much in agreement with each other. Judge for yourself in scrolling through the Discussion chapter. The divergence leads to the “why” it is necessary to switch to organic farming not on the “need” to do so. There are also disappointments about the use of GMOs orthe costs of highly technological agriculture. The situation is such on planet Earth that it is necessary to involve the whole society to get out of it. In addition, politicians are also needed to structure the collective action that only if conceived by the whole society and not by individuals or by non-coordinated organizations can save our species. We are convinced that agriculture and soil are among the fundamental levers of this action.

During the last century, soils have been over-exploited by humans through agriculture and industrial development. The need to assess different aspects of soil degradation has become a priority in the soil protection management. Among several indices developed in the last years, QBS-ar (Soil Biological Quality-arthropod) index joins the biodiversity of soil microarthropods community with the degree of soil vulnerability. Up to now, numerous publications have reported the results of the QBS-ar application. This paper starts a review process for QBS-ar assessment by taking into account its potential in highlighting the relationship between soil quality and different land uses. In order to clarify the relationship between QBS-ar values and land use, we collected 41 published papers that reported of QBS-ar applications. In this framework, another aim of this paper is to make a critical review of the QBS-ar in respect to applications in different environmental contexts, and to obtain critical indication about problem and potential of QBS-ar for monitoring activities. We collected published data on QBS-ar and we individualized eight groupages in relation to soil uses: 1) Agriculture lands (A, several crops, till and no-tillage, organic, conventional), 2) Woods (W, forests, maquis and bushes), 3) Restored (R, plant remediation, restored pit mine, peri -urban uncultivated areas), 4) Natural degradation (ND, soils in natural degraded conditions, e.g. serpentine soils, soil in the brUle), 5) Permanent grasslands, pastures and meadows (G), 6) Orchards (O), 7) Urban parks, residual urban woods, public gardens, botanical gardens, home gardens (UP), 8) Soils involved in human degradation (D). The results confirmed that land use significantly affects QBS-ar values. The overall mean of QBS-ar = 93.7 can be considered a tentative threshold that separates high quality soils and values which are typical for poor soils. In the end, we would like to affirm the validity of this index, which, allows to evaluate the suffering state of soils and its potentiality for an expeditious use to evaluate soil biological quality in recovery areas.

The use of conservation and sustainable practices could restore the abundance and richness of soil organisms in agroecosystems. Fitting in this context, this study aimed to highlight whether and how different soil living communities reacted to the conversion from an integrated to an organic orchard. The metataxonomic approach for fungi and bacteria and the determination of biological forms of diatoms and microarthropods were applied. Soil analyses were carried out in order to evaluate the effect of soil chemical features on four major soil living communities. Our results showed that the different taxa reacted with different speeds to the management changes. Fungi responded quickly to the changes, suggesting that modification in agricultural practices had a greater impact on fungal communities. Bacteria and microarthropods were more affected by abiotic parameters and less by the management. The diatom composition seemed to be affected by seasonality but the highest H’ (Shannon index) value was measured in the organic system. Fungi, but also diatoms, seemed to be promising for monitoring changes in the soil since they were sensitive to both the soil features and the anthropic impact. Our study showed that soil biodiversity could be affected by the conversion to sustainable management practices from the early years of an orchard onwards. Therefore, better ecological orchard management may strengthen soil sustainability and resilience in historically agricultural regions.

Climate change is predicted to increase drought and flooding events in the coming decades, especially in the tropics; we need to understand the short-term responses of plant community and soil microarthropods populations to these extreme events.Yet most of our current knowledge on this comes from manipulative studies in temperate regions. The present study reports the impact of a severe summer drought followed by a catastrophic flood in 2018 on soil microarthropod density and biological soil quality across 25 tropical home gardens. Drought reduced the density of organisms six-fold and flooding caused a further threefold reduction. Biological soil quality in the home gardens that were not flooded was restored during the monsoon season but this was just partially possible for microarthropod population size. Three months after flooding, the microarthropod groups encountered were generally able to re-establish their population to the condition prior to flooding. However, none of the group recovered to the mean seasonal values. The severity of previous drought seemed to have overridden any possible adaptation to annual summer water scarcity. Plant species richness in home gardens played a key role towards mitigation and possible resilience to disturbance of these ancient agroecosystems. The capacity of the soil microarthropod communities to recover over the long term after extreme climatic events and its relevance to maintaining ecosystem functions and services in home gardens through soil fertility warrant further investigation.

Landslides are common in the Northern Apennines (Italy) and their resulting changes in soil structure affect edaphic fauna biodiversity, whose activity has concurrent impacts on soil structural stability and water-holding capacity. The aim of this study was to characterise landslide evolution and assess potential relationships between its hydrogeological features and soil fauna. The landforms of the study area, located in the River Taro valley, were mapped and the hydraulic head fluctuations and groundwater electrical conductivity profiles were measured. The soil arthropod community was studied in seven sites, one subject to earth flow and six to rotational slide, the last ones were divided into the main scarp of the slide, and five sites characterized by different land use: three grassland, a wheat cultivated field and an overgrown area. Soil organic matter (SOM) and pH measurements were performed. Hydrogeological results suggest unexpected rapid percolation of relatively low-salinity waters through the unsaturated zone. Both lower SOM content and arthropod biodiversity were found in earth flow area, while higher values were found in grasslands. Fauna composition appears to be a good indicator of soil degradation processes, linked to the hydraulic features, and contributes to the evaluation of the soil condition in landslide areas for further agricultural purposes.

Soil biodiversity and habitat provisioning is one of the soil functions that agricultural land provides to society. This paper describes assessment of the soil biodiversity function (SB function) as a proof of concept to be used in a decision support tool for agricultural land management. The SB function is defined as ‘the multitude of soil organisms and processes, interacting in an ecosystem, providing society with a rich biodiversity source and contributing to a habitat for aboveground organisms.’ So far, no single measure provides the full overview of the soil biodiversity and how a soil supports a habitat for a biodiverse ecosystem. We have assembled a set of attributes for a proxy-indicator system, based on four ‘integrated attributes’: 1) soil nutrient status, 2) soil biological status, 3) soil structure, and 4) soil hydrological status. These attributes provide information to be used in a model for assessing the capacity of a soil to supply the SB function. A multi-criteria decision model was developed which comprises of 34 attributes providing information to quantify the four integrated attributes and subsequently assess the SB function for grassland and for cropland separately. The model predictions (in terms of low – moderate – high soil biodiversity status) were compared with expert judgements for a collection of 137 grassland soils in the Netherlands and 52 French soils, 29 grasslands and 23 croplands. For both datasets, the results show that the proposed decision model predictions were statistically significantly correlated with the expert judgements. A sensitivity analysis indicated that the soil nutrient status, defined by attributes such as pH and organic carbon content, was the most important integrated attribute in the assessment of the SB function. Further progress in the assessment of the SB function is needed. This can be achieved by better information regarding land use and farm management. In this way we may make a valuable step in our attempts to optimize the multiple soil functions in agricultural landscapes, and hence the multifaceted role of soils to deliver a bundle of ecosystem services for farmers and citizens, and support land management and policy towards a more sustainable society.

Hydrocarbon pollution threatens aquatic and terrestrial ecosystems globally, but soil fauna in oil-polluted soils has been insufficiently studied. In this research, soil hydrocarbon toxicity was investigated in two natural oil seepage soils in Val D&rsquo, Agri (Italy) using two different approaches: (i) toxicological tests with Folsomia candida (Collembola) and Eisenia fetida (Oligochaeta) and (ii) analysis of abundance and composition of micro- and meso-fauna. Soil sampling was done along 20 m-transepts starting from the natural oil seepages. Toxicological testing revealed that no exemplars of F. candida survived, whereas specimens of E. fetida not only survived but also increased in weight in soils with higher PAH concentrations, although no reproduction was observed. Analysis on microfauna showed that Nematoda was the most abundant group, with distance from seepages not affecting its abundance. Arthropoda results showed that Acarina, Collembola and Diptera larvae represented the most abundant taxa. The highest divergence in community composition was found between soils situated near seepages and at 5 m and 10 m distance. Arthropoda taxa numbers, total abundance and Acarina were lower in soils with high PAH concentration, while Diptera larvae were not significantly affected. Earthworms, together with Nematoda and Diptera larvae, could therefore represent ideal candidates in PAH degradation studies.

Truffles contribute both directly and indirectly to important dynamics in the soil web, being involved in a large number of ecological functions that are crucial for terrestrial ecosystems. Despite this, the interrelationships between true truffles, i.e. hypogeous ectomycorrhizal fungi producing valuable fruiting bodies, and other elements of the soil system are largely unknown. In this study, we aimed to shed new light on whether and how much Tuber aestivum affects soil microbial activities (evaluated as enzyme activities), abundance (assayed as soil DNA content) and bacterial genetic diversity along with soil chemical properties. We compared chemical and biological variables inside and outside brules (i.e. areas inhabited by truffles with scarce vegetation cover around host plants) in two seasons, namely spring and summer, using both a linear mixed model and a multivariate two-block partial least squares approach. The areas with truffle presence had higher pH but lower organic carbon and nitrogen content. Similarly, all enzyme activities were lower inside the brule than outside, with the exception of peroxidase. A soil quality index (i.e. AI3) based on three enzyme activities (β-glucosidase, acid phosphomonoesterase and urease) indicated a reduction in soil quality inside the brule. Overall, soil DNA content responded to an interaction of truffle presence/absence and season, while bacterial genetic diversity indexes were higher in spring. Despite the observational nature of this study, results point out that T. aestivum can be considered a key species in the soil where it is present as it was associated with changes in chemistry as well as microbial activity that were generally more conspicuous than mere seasonal effects, although the causative nature of these associations still needs to be confirmed.

Conventional farming (CONV) is the norm in European farming, causing adverse effects on some of the five major soil functions, viz. primary productivity, carbon sequestration and regulation, nutrient cycling and provision, water regulation and purification, and habitat for functional and intrinsic biodiversity. Conservation agriculture (CA) is an alternative to enhance soil functions. However, there is no analysis of CA benefits on the five soil functions as most studies addressed individual soil functions. The objective was to compare effects of CA and CONV practices on the five soil functions in four major environmental zones (Atlantic North, Pannonian, Continental and Mediterranean North) in Europe by applying expert scoring based on synthesis of existing literature. In each environmental zone, a team of experts scored the five soil functions due to CA and CONV treatments and median scores indicated the overall effects on five soil functions. Across the environmental zones, CONV had overall negative effects on soil functions with a median score of 0.50 whereas CA had overall positive effects with median score ranging from 0.80 to 0.83. The study proposes the need for field-based investigations, policies and subsidy support to benefit from CA adoption to enhance the five soil functions. Unión Europea 635201 Unión Europea 652615 Unión Europea 689271

Litter decomposition is an ecosystem process that is regulated by a multitude of factors and by their complex interactions. Current decomposition paradigms do not always offer a coherent view of the process because it can be hardly understood without a thorough analysis of interacting factors. Thus, there is a need to further understand the mechanics of litter decay with a comprehensive approach, especially in temperate forest ecosystems where decomposition plays a crucial role in regulating them as source or sink of CO2. Therefore, the aim of this work was to identify the interactions between chemical, biological and soil fauna variables in order to discern driving variables and the changes in their interactions during long-time (1300 days) beech leaf litter decomposition. In order to investigate patterns of variation and co-variation within and between datasets, we used Two-block Partial Least Squares, helping us to interpret the decomposition process with a systemic approach. Our key findings showed that the decomposition process of beech litter in two Mediterranean forests was driven by litter quality at the beginning and in the later stages of decomposition, while edaphic and climatic factors were implied in the central steps, with a dramatic change of scenario around 2.5 years. Simultaneous and interacting changes in chemical variables, extracellular enzyme activities, and soil fauna were shown, with a significant role of lignocellulosic components and enzymes involved in their degradation, Mn residual weight, and abundance of Collembola.

Enzymes play a key-role in organic matter dynamics and strong scientific attention has been given to them lately, especially to their response to climate and substrate chemical composition. Accordingly, in this study, we investigated the effects of chemical composition and seasons on extracellular enzyme activities (laccase, peroxidase, cellulase, chitinase, acid phosphomonoesterase, and dehydrogenase) by means of multilevel models within two Italian mountain beech forests. We used chemical variables as the fixed part in the model, season as random variation and layers (decomposition continuum for leaf litter and 0–5, 5–15, 15–30, and 30–40 cm for soil) as nested factors within the two forests. Our results showed that seasonal changes explained a higher amount of variance in enzyme activities compared to substrate chemistry in leaf litter, whereas chemical variation had a stronger impact on soil. Moreover, the effect of seasonality and chemistry was in general larger than the differences between forest sites, soils, and litter layers.

Mining causes significant damage to the environment: the removal of top layers of soil causes loss of structure and functionality, with a subsequent reduction in biodiversity. Soil communities are important for soil formation, they contribute to the improvement of several characteristics of soils and they play key roles in many processes that enhance the success of restoration. Unfortunately, soil fauna are poorly monitored even though they represent a good tool for assessing soil quality. The “La Speranza” quarry in northern Italy was studied from the start of the restoration process in 2008 until 2012. Six sites were selected and monitored annually. Microarthropods were extracted from three replicates of soil drawn from each site, identified to order level and then counted. Both the abundances of taxa and the soil biological indices applied (Shannon diversity index (H’), Pielou's evenness index (J), the Acari to Collembola ratio (A/C) and the QBS-ar index) revealed a good level of soil recovery over the years studied. Furthermore, the edaphic organisms that are generally associated with stable conditions in the soil (e.g. Symphyla, Protura, Chilopoda), appeared in the most recent of the years.

Agriculture and forestry traditionally focus on improving plant growth traits based on an anthropocentric point of view. This paradigm has led to global problems associated to soil overexploitation such as soil losses, reductions of the C stock in soils, and the generalized use of fertilizers, which particularly increases the costs of production and pollution treatment. This view may also have limited our understanding of mutualistic symbioses of plants and microorganisms assuming that the main role of non-photosynthetic symbionts is to mobilize the nutrients that are necessary for plant growth and development, and being plants the dominant agents of the symbiotic relationship. In response to these issues, this chapter offers an alternative approach taking advantage of the “rhizo-centric” point of view, where non-photosynthetic partners are the main protagonists in play; and secondly, it builds a multidisciplinary body of knowledge that could be called “rhizoculture”, which includes techniques focussing on the intensification of the development and activity of roots, mycorrhizae, and other symbiotic and free living rhizosphere organisms. In short, rhizoculture may lead to decrease plant production dependence on fertilization and provides other benefits to agriculture, forestry, and the environment. Within this conceptual framework, the first objective of this book chapter is to explore whether there is a “paradox of calcium salts” (i.e., Ca2+ and its salts are simultaneously nutrients, promoters, and stressors for the host plants) that would explain a dominance of mycorrhizal fungi over plants based on inducing a Ca(pH)–mediated chlorosis to the host plants. If this paradigm shifting hypothesis were finally fully verified, it would provide conceptual bases to reconsider our current technologies in agriculture and forestry by introducing the “rhizocultural” approach, based on the management of roots (introducing alternative cultural practices), Ca2+ salts (using liming and other techniques), rock-eating mycorrhizae, organic matter, and the soil microbiome (increasing the presence of symbiotic microorganisms against saprophytes), N and P contents (by aquaculture and smart recycling of organic waste), and the physical properties of the soil (by the activity of soil symbiotic microorganisms and soil fauna, such as ants, termites and earthworms). The development of such new technological approaches in rhizoculture would significantly decrease the high cost and associated pollution of the application of fertilizers and phytochemicals; as well as it would increase soil C stocks, improve the resilience of agricultural and forest systems to environmental disturbances, such as climate change, and enhance food production and security.

In vitro short-term chronic phytotoxicity germination and root elongation test were applied to test the effects of nickel (Ni) in seed germination and root elongation in six plants species: Cucumis sativus (Cucurbitaceae), Lepidium sativum and Brassica nigra (Brassicaceae), Trifolium alexandrinum and Medicago sativa (Fabaceae), Phacelia tanacetifolia (Boraginaceae). A naturally Ni rich soil was used to compare the results obtained. Unlike root elongation, germination was not affected by Ni in any of the six species tested. EC50 values, calculated on the root elongation, showed that Ni toxicity decreases in the following order: P. tanacetifolia > B. nigra > C. sativus > L. sativum > M. sativa > T. alexandrinum. The test conducted using soil elutriate revealed a significantly lower effect in both seed germination and root elongation when compared to the results obtained using untreated soil. Conversely, the test performed on soil confirmed the high sensitivity of C. sativus, P. tanacetifolia and L. sativum to Ni.

Granules of calcium carbonate are known to be produced by the calciferous glands of earthworms, and may have a measurable impact on the soil; however, little is known of their dynamics. Earthworms are often found in Tuber melanosporum burns, and this truffle is closely linked to calcium carbonate and soil pH. The present work shows that in weakly calcareous soil burns with high earthworm (Prosellodrilus sp.) activity, earthworm casts showed a significant increase of 0.2 units of pH and 66 % more total calcium carbonate than soils in the burns, although the casts were produced from these same soils. Analysis of the soil carbonate fractions (active carbonate versus calcium carbonate greater than 50 μm in size) showed that the origin of the increase in the total calcium carbonate content of the Prosellodrilus sp. casts cannot be explained by the levels of original carbonate existing in the soils in the study, although it can be explained by the synthesis of calcite granules by earthworms. These results obtained in the field with Prosellodrilus sp. confirm Canti’s (2009) experiments in the laboratory using δ13C concerning the synthesis of calcite granules by Lumbricus terrestris. Both these results and other works indicate that production of calcite granules by Prosellodrilus sp., L. terrestris, Aporrectodea longa, A. trapezoides and Anisochaetae sp. has the ability to increase soil pH and calcium carbonate; additionally Lambkin et al. (2011) have found that higher soil pH and carbonates can cause an increase in the production of calcite granules by L. terrestris. All these results, therefore, point to a feedback process, scope of which is a function of the different soil types and earthworm species. In summary, different earthworm species may have a significant and positive impact on soil pH and net recarbonation of T. melanosporum burns, and the importance of both soil properties justifies the development of further experiments aimed at incorporating vermiculture into the truffle cultivations.

Eco-toxicological or bioassay tests have been intensively discussed as tools for the evaluation of soil quality. Tests using soil organisms, including microarthropods and plants, allow direct estimates to be made of important soil characteristics and functions. In this study we compared the results obtained by two in vitro standard bioassays following ISO or OECD guidelines: (i) the short term-chronic phytotoxicity germination and root elongation test using three different plant species Cucumis sativus L. (Cucurbitaceae), Lepidium sativum L. (Brassicaceae), and Medicago sativa L. (Fabaceae) and (ii) the inhibition of reproduction of Folsomia candida (Collembola) by soil pollutants to investigate the toxicity of a serpentine soil present in the Italian Apennines, rich in heavy metals such as Ni, Cr, and Co. In addition, microarthropod communities were characterised to evaluate the effects of metal contents on the soil fauna in natural conditions. Abundances, Acari/Collembola ratio, biodiversity indices and the QBS-ar index were calculated. Our results demonstrate that the two in vitro tests distinguish differences correlated with metal and organic matter contents in four sub-sites within the serpentinite. Soil fauna characterisation, not previously performed on serpentine soils, revealed differences in the most vulnerable and adapted groups of microarthropods to soil among the four sub-sites: the microarthropod community was found to be rich in term of biodiversity in the sub-site characterised by a lower metal content and a higher organic matter content and vegetation.

There are numerous aspects related to Tuber species, which have not been explored to date. Tuber aestivum Vitt. is an ectomycorrhizal fungus, that produces an area (called brule) around the host plant trunk, where the germination of other plants is inhibited. What happens inside this particular environment is still not sufficiently understood, especially in terms of soil fauna. A previous work showed that there were higher microarthropod abundances outside during the period of maximum activity of the mycelium. The genus Folsomia (Isotomidae Family; Order Collembola) showed higher abundance inside. The aim of this paper is to investigate the effects of brule, on soil parameters and soil fauna, during the annual biological cycle of T. aestivum. This study was carried out in nine spontaneous brules situated in Northern Italy (Emilia Romagna Region – Piacenza Province). Soil cores were collected in order to perform soil chemical and biological analysis. Moisture content, pH, organic matter content, total organic carbon were analyzed. Biodiversity and soil quality indices were applied. We found higher pH, lower carbon and organic matter content within the brule. Soil fauna community also showed some differences, seasonal and inside vs outside the brule. Some groups seem to be negatively affected by Tuber while Folsomia genus recorded almost always higher values inside. These results suggest that some organisms, such as some Collembola, might find a favorable environment inside the brule, while others - a negative one. However, these results should be compared by other analysis either on other Tuber species and on other soil organisms, such as nematodes and earthworms.

Biochar is a product of the thermal decomposition of biomass under a limited supply of oxygen and can be deriving from pyrolysis or gasification. As the product is rich in highly recalcitrant carbon, it has been proposed as a soil amendment to improve soil fertility and to stock carbon in soils. However, the contaminant compounds present in biochar could represent potential environmental threats. The gasification biochar is a promising by-product, but its effects on soil microarthropods are still nearly unknown. The aim of this study was to assess, using a prognosis approach, any ecotoxicological consequences of four biochars (conifer, poplar, grape marc, and wheat straw) on the springtail Folsomia candida. This was assessed through a series of tests: an avoidance behavior test, a survival and reproduction test, and a test based on the hatching of eggs. Biochars were tested at different concentrations (pulverized and diluted w/w with an artificial standard soil). The results showed that the springtails did not tend to avoid the biochars' substrates up to the rate of 2-5%, but any higher levels of concentration caused the animals to keep away from it. While mortality was negatively affected only in the grape marc biochar, reproduction was significantly reduced in all biochars considered. The hatching of the eggs was anticipated at even the lowest concentrations of herbaceous biochars, while a severe delay was observed in both concentrations tested of the conifer biochar. The endpoints considered were negatively affected by pH, polycyclic aromatic hydrocarbons, and heavy metals (in order of importance). The findings confirmed the potential adverse effects that gasification biochars could have on soil microarthropods and demonstrated the necessity of introducing these tests into biochar characterization protocols.