Beat Stierli

Earthworms and enchytraeids play an important role in biogeochemical cycles and are good indicators of soil fertility. However, assessing their assemblages is difficult, mainly because the methods to identify them require expert knowledge, which becomes a technical challenge when surveying large areas. Soil DNA metabarcoding is a promising method that enables the identification of individual species directly from a bulk composite sample in large field experiments. Here, we investigated in parallel both earthworm (family Lumbricidae) and enchytraeid (family Enchytraeidae) assemblages in three land-use types (arable land, grassland, forest) across 29 Swiss Soil Monitoring Network (NABO) sites, using high-throughput amplicon sequencing of marker genes. For both earthworms and enchytraeids, α-diversity was higher in grasslands than in arable land and forests, and it was significantly affected by soil physico-chemical, climate and biological properties, especially pH and climate properties. In addition, we found negative correlations between earthworms α-diversity and soil total carbon (TC) content and the soil carbon to nitrogen ratio. Using the DNA metabarcoding, we observed sequences of Aporrectodea nocturna in soils with low pH, while other Aporrectodea species occurred in soils with high pH. We identified Bimastos rubidus in soils with low pH but higher TC, total nitrogen, organic C, and low silt content, while the enchytraeids Cognettia sphagnetorum and Cernosvitoviella atrata occurred in forest soils with high water and organic matter contents. We identified some indicator taxa for the different land-use types, for grassland: Aporrectodea icterica, Lumbricus rubellus, Marionina communis, Fridericia bisetosa and Fridericia connata; arable land: Allolobophora chlorotica, Enchytraeus dichaetus, Achaeta iberica, Prodtodrilus antipae and Fridericia tuberosa; and for forest: Octolasion cyaneum, Octolasion lacteum and Cognettia chlorophila. Although these indicator taxa are unlikely to provide information about the effect of land-use change on soil biodiversity at large spatial scales, these species do drive assemblage differences between land-use types. Soil DNA metabarcoding could therefore assist land managers in monitoring soil biodiversity and quality.

Climate warming has led to glacier retreat worldwide. Studies on the taxonomy and functions of glacier microbiomes help us better predict their response to glacier melting. Here, we used shotgun metagenomic sequencing to study the microbial functional potential in different cryospheric habitats, i.e. surface snow, supraglacial and subglacial sediments, subglacial ice, proglacial stream water and recently deglaciated soils. The functional gene structure varied greatly among habitats, especially for snow, which differed significantly from all other habitats. Differential abundance analysis revealed that genes related to stress responses (e.g. chaperones) were enriched in ice habitat, supporting the fact that glaciers are a harsh environment for microbes. The microbial metabolic capabilities related to carbon and nitrogen cycling vary among cryospheric habitats. Genes related to auxiliary activities were overrepresented in the subglacial sediment, suggesting a higher genetic potential for the degradation of recalcitrant carbon (e.g., lignin). As for nitrogen cycling, genes related to nitrogen fixation were more abundant in barren proglacial soils, possibly due to the presence of Cyanobacteriota in this habitat. Our results deepen our understanding of microbial processes in glacial ecosystems, which are vulnerable to ongoing global warming, and they have implications for downstream ecosystems.

Plastic materials, including microplastics, accumulate in all types of ecosystems, even in remote and cold environments such as the European Alps. This pollution poses a risk for the environment and humans and needs to be addressed. Using shotgun DNA metagenomics of soils collected in the eastern Swiss Alps at about 3,000 m a.s.l., we identified genes and their proteins that potentially can degrade plastics. We screened the metagenomes of the plastisphere and the bulk soil with a differential abundance analysis, conducted similarity-based screening with specific databases dedicated to putative plastic-degrading genes, and selected those genes with a high probability of signal peptides for extracellular export and a high confidence for functional domains. This procedure resulted in a final list of nine candidate genes. The lengths of the predicted proteins were between 425 and 845 amino acids, and the predicted genera producing these proteins belonged mainly to Caballeronia and Bradyrhizobium. We applied functional validation, using heterologous expression followed by enzymatic assays of the supernatant. Five of the nine proteins tested showed significantly increased activities when we used an esterase assay, and one of these five proteins from candidate genes, a hydrolase-type esterase, clearly had the highest activity, by more than double. We performed the fluorescence assays for plastic degradation of the plastic types BI-OPL and ecovio^® only with proteins from the five candidate genes that were positively active in the esterase assay, but like the negative controls, these did not show any significantly increased activity. In contrast, the activity of the positive control, which contained a PLA-degrading gene insert known from the literature, was more than 20 times higher than that of the negative controls. These findings suggest that in silico screening followed by functional validation is suitable for finding new plastic-degrading enzymes. Although we only found one new esterase enzyme, our approach has the potential to be applied to any type of soil and to plastics in various ecosystems to search rapidly and efficiently for new plastic-degrading enzymes.

Over recent decades, there has been a noticeable change in vegetation diversity accompanied by increased plant productivity in tundra systems of the High-Arctic, leading to elevated carbon and nutrient inputs into the soil. This shift can alter microbial community composition and activity in these ecosystems. In this study, we aimed to identify genes transcribed by active microorganisms and compare their expression in unamended and amended soils with labile carbon and/or nitrogen compounds. We also assessed gene expression differences in tundra soils with varying edaphic characteristics (upslope vs. downslope sites). We amended soils with either glycine or cellulose or left them unamended (i.e., control) for 7 days of incubation, and we isolated and sequenced RNA using Illumina technology. Whereas we observed only a weak transcriptional response after cellulose addition, the glycine addition significantly influenced transcriptional patterns, with upregulation of carbon- and nitrogen-cycling genes. Notably, microbial taxa from the Pseudomonadaceae and Micrococcaceae families showed the most pronounced response to glycine, indicating a shift of the communities towards copiotrophic organisms. This response was consistent across the two soil types, suggesting a common impact on microbial community activity. These findings suggest that an increase in carbon and nitrogen inputs could substantially affect microbial functioning in High-Arctic tundra soils, with potential implications for ecosystem dynamics under global warming.

Glacier retreat is a visible consequence of climate change worldwide. Although taxonomic change of the soil microbiomes in glacier forefields have been widely documented, how microbial genetic potential changes along succession is little known. Here, we used shotgun metagenomics to analyse whether the soil microbial genetic potential differed between four stages of soil development (SSD) sampled along three transects in the Damma glacier forefield (Switzerland). The SSDs were characterized by an increasing vegetation cover, from barren soil, to biological soil crust, to sparsely vegetated soil and finally to vegetated soil. Results suggested that SSD significantly influenced microbial genetic potential, with the lowest functional diversity surprisingly occurring in the vegetated soils. Overall, carbohydrate metabolism and secondary metabolite biosynthesis genes overrepresented in vegetated soils, which could be partly attributed to plant–soil feedbacks. For C degradation, glycoside hydrolase genes enriched in vegetated soils, while auxiliary activity and carbohydrate esterases genes overrepresented in barren soils, suggested high labile C degradation potential in vegetated, and high recalcitrant C degradation potential in barren soils. For N-cycling, organic N degradation and synthesis genes dominated along succession, and gene families involved in nitrification were overrepresented in barren soils. Our study provides new insights into how the microbial genetic potential changes during soil formation along the Damma glacier forefield.

Real-time quantitative PCR (qPCR) has been widely used to quantify gene copy numbers in microbial ecology. Despite its simplicity and straightforwardness, establishing qPCR assays is often impeded by the tedious process of producing qPCR standards by cloning the target DNA into plasmids. Here, we designed double-stranded synthetic DNA fragments from consensus sequences as qPCR standards by aligning microbial gene sequences (10–20 sequences per gene). Efficiency of standards from synthetic DNA was compared with plasmid standards by qPCR assays for different phylogenetic marker and functional genes involved in carbon (C) and nitrogen (N) cycling, tested with DNA extracted from a broad range of soils. Results showed that qPCR standard curves using synthetic DNA performed equally well to those from plasmids for all the genes tested. Furthermore, gene copy numbers from DNA extracted from soils obtained by using synthetic standards or plasmid standards were comparable. Our approach therefore demonstrates that a synthetic DNA fragment as qPCR standard provides comparable sensitivity and reliability to a traditional plasmid standard, while being more time- and cost-efficient.

Climate change can alter the flow of nutrients and energy through terrestrial ecosystems. Using an inverse climate change field experiment in the central European Alps, we explored how long-term irrigation of a naturally drought-stressed pine forest altered the metabolic potential of the soil microbiome and its ability to decompose lignocellulolytic compounds as a critical ecosystem function. Drought mitigation by a decade of irrigation stimulated profound changes in the functional capacity encoded in the soil microbiome, revealing alterations in carbon and nitrogen metabolism as well as regulatory processes protecting microorganisms from starvation and desiccation. Despite the structural and functional shifts from oligotrophic to copiotrophic microbial lifestyles under irrigation and the observation that different microbial taxa were involved in the degradation of cellulose and lignin as determined by a time-series stable-isotope probing incubation experiment with ¹³C-labeled substrates, degradation rates of these compounds were not affected by different water availabilities. These findings provide new insights into the impact of precipitation changes on the soil microbiome and associated ecosystem functioning in a drought-prone pine forest and will help to improve our understanding of alterations in biogeochemical cycling under a changing climate.

Increasing plastic production and the release of some plastic in to the environment highlight the need for circular plastic economy. Microorganisms have a great potential to enable a more sustainable plastic economy by biodegradation and enzymatic recycling of polymers. Temperature is a crucial parameter affecting biodegradation rates, but so far microbial plastic degradation has mostly been studied at temperatures above 20°C. Here, we isolated 34 cold-adapted microbial strains from the plastisphere using plastics buried in alpine and Arctic soils during laboratory incubations as well as plastics collected directly from Arctic terrestrial environments. We tested their ability to degrade, at 15°C, conventional polyethylene (PE) and the biodegradable plastics polyester-polyurethane (PUR; Impranil^®); ecovio^® and BI-OPL, two commercial plastic films made of polybutylene adipate-co-terephthalate (PBAT) and polylactic acid (PLA); pure PBAT; and pure PLA. Agar clearing tests indicated that 19 strains had the ability to degrade the dispersed PUR. Weight-loss analysis showed degradation of the polyester plastic films ecovio^® and BI-OPL by 12 and 5 strains, respectively, whereas no strain was able to break down PE. NMR analysis revealed significant mass reduction of the PBAT and PLA components in the biodegradable plastic films by 8 and 7 strains, respectively. Co-hydrolysis experiments with a polymer-embedded fluorogenic probe revealed the potential of many strains to depolymerize PBAT. Neodevriesia and Lachnellula strains were able to degrade all the tested biodegradable plastic materials, making these strains especially promising for future applications. Further, the composition of the culturing medium strongly affected the microbial plastic degradation, with different strains having different optimal conditions. In our study we discovered many novel microbial taxa with the ability to break down biodegradable plastic films, dispersed PUR, and PBAT, providing a strong foundation to underline the role of biodegradable polymers in a circular plastic economy.

Background Global warming is affecting all cold environments, including the European Alps and Arctic regions. Here, permafrost may be considered a unique ecosystem harboring a distinct microbiome. The frequent freeze-thaw cycles occurring in permafrost-affected soils, and mainly in the seasonally active top layers, modify microbial communities and consequently ecosystem processes. Although taxonomic responses of the microbiomes in permafrost-affected soils have been widely documented, studies about how the microbial genetic potential, especially pathways involved in C and N cycling, changes between active-layer soils and permafrost soils are rare. Here, we used shotgun metagenomics to analyze the microbial and functional diversity and the metabolic potential of permafrost-affected soil collected from an alpine site (Val Lavirun, Engadin area, Switzerland) and a High Arctic site (Station Nord, Villum Research Station, Greenland). The main goal was to discover the key genes abundant in the active-layer and permafrost soils, with the purpose to highlight the potential role of the functional genes found.
Results We observed differences between the alpine and High Arctic sites in alpha- and beta-diversity, and in EggNOG, CAZy, and NCyc datasets. In the High Arctic site, the metagenome in permafrost soil had an overrepresentation (relative to that in active-layer soil) of genes involved in lipid transport by fatty acid desaturate and ABC transporters, i.e. genes that are useful in preventing microorganisms from freezing by increasing membrane fluidity, and genes involved in cell defense mechanisms. The majority of CAZy and NCyc genes were overrepresented in permafrost soils relative to active-layer soils in both localities, with genes involved in the degradation of carbon substrates and in the degradation of N compounds indicating high microbial activity in permafrost in response to climate warming.
Conclusions Our study on the functional characteristics of permafrost microbiomes underlines the remarkably high functional gene diversity of the High Arctic and temperate mountain permafrost, including a broad range of C- and N-cycling genes, and multiple survival and energetic metabolisms. Their metabolic versatility in using organic materials from ancient soils undergoing microbial degradation determine organic matter decomposition and greenhouse gas emissions upon permafrost thawing. Attention to their functional genes is therefore essential to predict potential soil-climate feedbacks to the future warmer climate.

Many carbon-related physiological questions in plants such as carbon (C) limitation or starvation have not yet been resolved thoroughly due to the lack of suitable experimental methodology. As a first step towards resolving these problems, we conducted infusion experiments with bonsai trees (Ficus microcarpa) and young maple trees (Acer pseudoplatanus) in greenhouse, and with adult Scots pine trees (Pinus sylvestris) in the field, that were “fed” with ¹³C-labelled glucose either through the phloem or the xylem. We then traced the ¹³C-signal in plant organic matter and respiration to test whether trees can take up and metabolize exogenous sugars infused. Ten weeks after infusion started, xylem but not phloem infusion significantly increased the δ¹³C values in both aboveground and belowground tissues of the bonsai trees in the greenhouse, whereas xylem infusion significantly increased xylem δ¹³C values and phloem infusion significantly increased phloem δ¹³C values of the adult pines in the field experiment, compared to the corresponding controls. The respiration measurement experiment with young maple trees showed significantly increased δ¹³C-values in shoot respired CO₂ at the time of four weeks after xylem infusion started. Our results clearly indicate that trees do translocate and metabolize exogenous sugars infused, and because the phloem layer is too thin, and thus xylem infusion can be better operated than phloem infusion. This tree infusion method developed here opens up new avenues and has great potential to be used for research on the whole plant C balance and its regulation in response to environmental factors and extreme stress conditions.

Soil microorganisms are key transformers of mercury (Hg), a toxic and widespread pollutant. It remains uncertain, however, how long-term exposure to Hg affects crucial microbial functions, such as litter decomposition and nitrogen cycling. Here, we used a metagenomic approach to investigate the state of soil functions in an agricultural floodplain contaminated with Hg for more than 80 years. We sampled soils along a gradient of Hg contamination (high, moderate, low). Hg concentrations at the highly contaminated site (36 mg kg^-1 dry soil on average) were approximately 10 times higher than at the moderately contaminated site (3 mg kg^-1 dry soil) and more than 100 times higher than at the site with low contamination (0.25 mg kg^-1 dry soil; corresponding to the natural background concentration in Switzerland). The analysis of the CAZy and NCyc databases showed that carbon and nitrogen cycling was not strongly affected with high Hg concentrations, although a significant change in the beta-diversity of the predicted genes was observed. The only functional classes from the CAZy database that were significantly positively overrepresented under higher Hg concentrations were genes involved in pectin degradation, and from the NCyc database dissimilatory nitrate reduction and N-fixation. When comparing between low and high Hg concentrations the genes of the EggNOG functional category of inorganic ion transport and metabolism, two genes encoding Hg transport proteins and one gene involved in heavy metal transport detoxification were among those that were highly significantly overrepresented. A look at genes specifically involved in detoxification of Hg species, such as the mer and hgc genes, showed a significant overrepresentation when Hg contamination was increased. Normalized counts of these genes revealed a dominant role for the phylum Proteobacteria. In particular, most counts for almost all mer genes were found in Betaproteobacteria. In contrast, hgc genes were most abundant in Desulfuromonadales. Overall, we conclude from this metagenomic analysis that long-term exposure to high Hg triggers shifts in the functional beta-diversity of the predicted microbial genes, but we do not see a dramatic change or breakdown in functional capabilities, but rather functional redundancy.

Soil microorganisms such as Bacteria and Archaea play important roles in the biogeochemical cycling of soil nutrients, because they act as decomposers or are mutualistic or antagonistic symbionts, thereby influencing plant growth and health. In the present study, we investigated the vertical distribution of soil metagenomes to a depth of 1.5 m in Swiss forests of European beech and oak species on calcareous bedrock. We explored the functional genetic potential of soil microorganisms with the aim to disentangle the effects of tree genus and soil depth on the genetic repertoire, and to gain insight into the microbial C and N cycling. The relative abundance of reads assigned to taxa at the domain level indicated a 5-10 times greater abundance of Archaea in the deep soil, while Bacteria showed no change with soil depth. In the deep soil there was an overrepresentation of genes for carbohydrate-active enzymes, which are involved in the catalyzation of the transfer of oligosaccharides, as well as in the binding of carbohydrates such as chitin or cellulose. In addition, N-cycling genes (NCyc) involved in the degradation and synthesis of N compounds, in nitrification and denitrification, and in nitrate reduction were overrepresented in the deep soil. Consequently, our results indicate that N-transformation in the deep soil is affected by soil depth and that N is used not only for assimilation but also for energy conservation, thus indicating conditions of low oxygen in the deep soil. Using shotgun metagenomics, our study provides initial findings on soil microorganisms and their functional genetic potential, and how this may change depending on soil properties, which shift with increasing soil depth. Thus, our data provide novel, deeper insight into the "dark matter" of the soil.

Global warming in mid-latitude alpine regions results in permafrost thawing, together with greater availability of carbon and nutrients in soils and frequent freeze–thaw cycles. Yet it is unclear how these multifactorial changes will shape the 1 m-deep permafrost microbiome in the future, and how this will in turn modulate microbially-mediated feedbacks between mountain soils and climate (e.g. soil CO₂ emissions). To unravel the responses of the alpine permafrost microbiome to in situ warming, we established a three-year experiment in a permafrost monitoring summit in the Alps. Specifically, we simulated conditions of warming by transplanting permafrost soils from a depth of 160 cm either to the active-layer topsoils in the north-facing slope or in the warmer south-facing slope, near the summit. qPCR-based and amplicon sequencing analyses indicated an augmented microbial abundance in the transplanted permafrost, driven by the increase in copiotrophic prokaryotic taxa (e.g. Noviherbaspirillum and Massilia) and metabolically versatile psychrotrophs (e.g. Tundrisphaera and Granulicella); which acclimatized to the changing environment and potentially benefited from substrates released upon thawing. Metabolically restricted Patescibacteria lineages vastly decreased with warming, as reflected in the loss of α-diversity in the transplanted soils. Ascomycetous sapro-pathotrophs (e.g. Tetracladium) and a few lichenized fungi (e.g. Aspicilia) expanded in the transplanted permafrost, particularly in soils transplanted to the warmer south-facing slope, replacing basidiomycetous yeasts (e.g. Glaciozyma). The transplantation-induced loosening of microbial association networks in the permafrost could potentially indicate lesser cooperative interactions between neighboring microorganisms. Broader substrate-use microbial activities measured in the transplanted permafrost could relate to altered soil C dynamics. The three-year simulated warming did not, however, enhance heterotrophic respiration, which was limited by the carbon-depleted permafrost conditions. Collectively, our quantitative findings suggest the vulnerability of the alpine permafrost microbiome to warming, which might improve predictions on microbially-modulated transformations of mountain soil ecosystems under the future climate.

Soil microorganisms such as bacteria and fungi play important roles in the biogeochemical cycling of soil nutrients, because they act as decomposers or are mutualistic or antagonistic symbionts, thereby influencing plant growth and health. In the present study, we investigated the vertical distribution of the soil microbiome to a depth of 2 m in Swiss drought-exposed forests of European beech and oaks on calcareous bedrock. We aimed to disentangle the effects of soil depth, tree (beech, oak), and substrate (soil, roots) on microbial abundance, diversity, and community structure. With increasing soil depth, organic carbon, nitrogen, and clay content decreased significantly. Similarly, fine root biomass, microbial biomass (DNA content, fungal abundance), and microbial alpha-diversity decreased and were consequently significantly related to these physicochemical parameters. In contrast, bacterial abundance tended to increase with soil depth, and the bacteria to fungi ratio increased significantly with greater depth. Tree species was only significantly related to the fungal Shannon index but not to the bacterial Shannon index. Microbial community analyses revealed that bacterial and fungal communities varied significantly across the soil layers, more strongly for bacteria than for fungi. Both communities were also significantly affected by tree species and substrate. In deep soil layers, poorly known bacterial taxa from Nitrospirae, Chloroflexi, Rokubacteria, Gemmatimonadetes, Firmicutes and GAL 15 were overrepresented. Furthermore, archaeal phyla such as Thaumarchaeota and Euryarchaeota were more abundant in subsoils than topsoils. Fungal taxa that were predominantly found in deep soil layers belong to the ectomycorrhizal Boletus luridus and Hydnum vesterholtii. Both taxa are reported for the first time in such deep soil layers. Saprotrophic fungal taxa predominantly recorded in deep soil layers were unknown species of Xylaria. Finally, our results show that the microbial community structure found in fine roots was well represented in the bulk soil. Overall, we recorded poorly known bacterial and archaeal phyla, as well as ectomycorrhizal fungi that were not previously known to colonize deep soil layers. Our study contributes to an integrated perspective on the vertical distribution of the soil microbiome at a fine spatial scale in drought-exposed forests.

Böden sind Lebensraum für unzählige Lebewesen, die beim Abbau und Umbau von organischer Substanz eine wichtige Rolle spielen. Gesunde Böden sind für die Nachhaltigkeit im Wald eine grundlegende Voraussetzung. Dieses Merkblatt gibt einen Einblick in die Vielfalt der Lebewesen in Waldböden. Es dient der Ausbildung und Information für Forstwart- und Biologielaborant- Lernende, Studierende und weiteren interessierten Personen aus dem Forstund Umweltbereich.

Les sols sont l'habitat d'innombrables organismes vivants qui jouent un rôle important dans la décomposition et la transformation de la matière organique. Des sols sains sont une condition essentielle de la durabilité en forêt. Cette Notice donne un aperçu de la diversité des organismes vivants dans les sols forestiers. Elle contribue à la formation et à l'information des apprentis forestiers-bûcherons ou laborantins en biologie, des étudiants et d'autres personnes intéressées issues des domaines forestier et environnemental.

Decomposition is a major flux of the carbon cycle in forest soils and understanding the involved processes is a key for budgeting carbon turnover. Decomposition is constrained by the presence of biological agents such as microorganisms and the underlying environmental conditions such as water availability. A metabarcoding approach of ribosomal markers was chosen to study the succession of bacterial and fungal decomposers on root litter. Litterbags containing pine roots were buried in a pine forest for two years and sequentially sampled. Decomposition and the associated communities were surveyed under ambient dry and long-term irrigation conditions. Early decomposition stages were characterized by the presence of fast-cycling microorganisms such as Bacteroidetes and Helotiales, which were then replaced by more specialized bacteria and litter-associated or parasitic groups such as Acidobacteria, white rots, and Pleosporales. This succession was likely driven by a decrease of easily degradable carbohydrates and a relative increase in persistent compounds such as lignin. We hypothesize that functional redundancy among the resident microbial taxa caused similar root decomposition rates in control and irrigated forest soils. These findings have important implications for drought-prone Alpine forests as frequent drought events reduce litter fall, but not litter decomposition, potentially resulting in lower carbon stocks.

Plastic waste in the environment is a significant threat due to its resistance to biological processes. Here we report the ability of fungal strains found on floating plastic debris to degrade plastics. In particular, we wanted to know which fungi grow on plastic debris floating in the shoreline, whether these fungi have the ability to degrade plastics, whether the plasticdegrading fungi can degrade other complex C-polymers such as lignin, and whether lignindegraders vice versa can also break down plastics. Overall, more than a hundred fungal strains were isolated from plastic debris of the shoreline of Lake Zurich, Switzerland, and grouped morphologically. Representative strains of these groups were then selected and genetically identified, altogether twelve different fungal species and one species of Oomycota. The list of fungi included commonly occurring saprotrophic fungi but also some plant pathogens. These fungal strains were then used to test the ability to degrade polyethylene and polyurethane. The tests showed that none of the strains were able to degrade polyethylene. However, four strains were able to degrade polyurethane, the three litter-saprotrophic fungi Cladosporium cladosporioides, Xepiculopsis graminea, and Penicillium griseofulvum and the plant pathogen Leptosphaeria sp. A series of additional fungi with an origin other than from plastic debris were tested as well. Here, only the two litter-saprotrophic fungi Agaricus bisporus and Marasmius oreades showed the capability to degrade polyurethane. In contrast, wood-saprotrophic fungi and ectomycorrhizal fungi were unable to degrade polyurethane. Overall, it seems that in majority only a few litter-saprotrophic fungi, which possess a wide variety of enzymes, have the ability to degrade polyurethane. None of the fungi tested was able to degrade polyethylene.

Böden sind Lebensraum für unzählige Lebewesen, die beim Abbau und Umbau von organischer Substanz eine wichtige Rolle spielen. Gesunde Böden sind für die Nachhaltigkeit im Wald eine grundlegende Voraussetzung. Dieses Merkblatt gibt einen Einblick in die Vielfalt der Lebewesen in Waldböden. Es dient der Ausbildung und Information für Forstwart- und Biologielaborant- Lernende, Studierende und weiteren interessierten Personen aus dem Forst- und Umweltbereich.

Les sols sont l’habitat d’innombrables organismes vivants qui jouent un rôle important dans la décomposition et la transformation de la matière organique. Des sols sains sont une condition essentielle de la durabilité en forêt. Cette Notice donne un aperçu de la diversité des organismes vivants dans les sols forestiers. Elle contribue à la formation et à l’information des apprentis forestiers-bûcherons ou laborantins en biologie, des étudiants et d’autres personnes intéressées issues des domaines forestier et environnemental.