TY - JOUR A1 - Kim, Shin Woong A1 - Leifheit, Eva F. A1 - Maaß, Stefanie A1 - Rillig, Matthias C. T1 - Time-dependent toxicity of tire particles on soil nematodes JF - Frontiers in Environmental Science N2 - Tire-wear particles (TWPs) are being released into the environment by wearing down during car driving, and are considered an important microplastic pollution source. The chemical additive leaching from these polymer-based materials and its potential effects are likely temporally dynamic, since amounts of potentially toxic compounds can gradually increase with contact time of plastic particles with surrounding media. In the present study, we conducted soil toxicity tests using the soil nematode Caenorhabditis elegans with different soil pre-incubation (30 and 75 days) and exposure (short-term exposure, 2 days; lifetime exposure, 10 days) times. Soil pre-incubation increased toxicity of TWPs, and the effective concentrations after the pre-incubation were much lower than environmentally relevant concentrations. The lifetime of C. elegans was reduced faster in the TWP treatment groups, and the effective concentration for lifetime exposure tests were 100- to 1,000-fold lower than those of short-term exposure tests. Water-extractable metal concentrations (Cr, Cu, Ni, Pb, and Zn) in the TWP-soils showed no correlation with nominal TWP concentrations or pre-incubation times, and the incorporated metals in the TWPs may be not the main reason of toxicity in this study. Our results show that toxic effects of TWPs can be time-dependent, both in terms of the microplastic particles themselves and their interactions in the soil matrix, but also because of susceptibility of target organisms depending on developmental stage. It is vital that future works consider these aspects, since otherwise effects of microplastics and TWPs could be underestimated. KW - Caenorhabditis elegans KW - exposure time KW - lifetime KW - microplastics KW - soil KW - incubation Y1 - 2021 U6 - https://doi.org/10.3389/fenvs.2021.744668 SN - 2296-665X VL - 9 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Lozano, Yudi M. A1 - Aguilar-Trigueros, Carlos A. A1 - Onandia, Gabriela A1 - Maaß, Stefanie A1 - Zhao, Tingting A1 - Rillig, Matthias C. T1 - Effects of microplastics and drought on soil ecosystem functions and multifunctionality JF - Journal of applied ecology : an official journal of the British Ecological Society N2 - 1. Microplastics in soils have become an important threat for terrestrial systems as they may potentially alter the geochemical/biophysical soil environment and can interact with drought. As microplastics may affect soil water content, this could exacerbate the well-known negative effects of drought on ecosystem functionality. Thus, functions including litter decomposition, soil aggregation or those related with nutrient cycling can be altered. Despite this potential interaction, we know relatively little about how microplastics, under different soil water conditions, affect ecosystem functions and multifunctionality. 2. To address this gap, we performed an experiment using grassland plant communities growing in microcosms. Microplastic fibres (absent, present) and soil water conditions (well-watered, drought) were applied in a fully factorial design. At harvest, we measured soil ecosystem functions related to nutrient cycling (beta-glucosaminidase, beta-D-cellobiosidase, phosphatase, beta-glucosidase enzymes), respiration, nutrient retention, pH, litter decomposition and soil aggregation (water stable aggregates). As terrestrial systems provide these functions simultaneously, we also assessed ecosystem multifunctionality, an index that encompasses the array of ecosystem functions measured here. 3. We found that the interaction between microplastic fibres and drought affected ecosystem functions and multifunctionality. Drought had negatively affected nutrient cycling by decreasing enzymatic activities by up to similar to 39%, while microplastics increased soil aggregation by similar to 18%, soil pH by similar to 4% and nutrient retention by up to similar to 70% by diminishing nutrient leaching. Microplastic fibres also impacted soil enzymes, respiration and ecosystem multifunctionality, but importantly, the direction of these effects depended on soil water status. That is, under well-watered conditions, these functions decreased with microplastic fibres by up to similar to 34% while under drought they had similar values irrespective of the microplastic presence, or tended to increase with microplastics. Litter decomposition had a contrary pattern increasing with microplastics by similar to 6% under well-watered conditions while decreasing to a similar percentage under drought. 4. Synthesis and applications. Single ecosystem functions can be positively or negatively affected by microplastics fibres depending on soil water status. However, our results suggest that microplastic fibres may cause negative effects on ecosystem soil multifunctionality of a similar magnitude as drought. Thus, strategies to counteract this new global change factor are necessary. KW - enzymatic activities KW - grasslands ecosystem KW - litter decomposition KW - nutrient cycling KW - nutrient leaching KW - soil aggregation KW - soil pH KW - soil respiration Y1 - 2021 U6 - https://doi.org/10.1111/1365-2664.13839 SN - 1365-2664 VL - 58 IS - 5 SP - 988 EP - 996 PB - Wiley-Blackwell CY - Oxford [u.a.] ER - TY - JOUR A1 - Lehmann, Anika A1 - Zheng, Weishuang A1 - Ryo, Masahiro A1 - Soutschek, Katharina A1 - Roy, Julien A1 - Rongstock, Rebecca A1 - Maaß, Stefanie A1 - Rillig, Matthias C. T1 - Fungal traits important for soil aggregation JF - Frontiers in microbiology N2 - Soil structure, the complex arrangement of soil into aggregates and pore spaces, is a key feature of soils and soil biota. Among them, filamentous saprobic fungi have well-documented effects on soil aggregation. However, it is unclear what properties, or traits, determine the overall positive effect of fungi on soil aggregation. To achieve progress, it would be helpful to systematically investigate a broad suite of fungal species for their trait expression and the relation of these traits to soil aggregation. Here, we apply a trait-based approach to a set of 15 traits measured under standardized conditions on 31 fungal strains including Ascomycota, Basidiomycota, and Mucoromycota, all isolated from the same soil. We find large differences among these fungi in their ability to aggregate soil, including neutral to positive effects, and we document large differences in trait expression among strains. We identify biomass density, i.e., the density with which a mycelium grows (positive effects), leucine aminopeptidase activity (negative effects) and phylogeny as important factors explaining differences in soil aggregate formation (SAF) among fungal strains; importantly, growth rate was not among the important traits. Our results point to a typical suite of traits characterizing fungi that are good soil aggregators, and our findings illustrate the power of employing a trait-based approach to unravel biological mechanisms underpinning soil aggregation. Such an approach could now be extended also to other soil biota groups. In an applied context of restoration and agriculture, such trait information can inform management, for example to prioritize practices that favor the expression of more desirable fungal traits. KW - soil aggregation KW - traits KW - saprobic fungi KW - random forest KW - biomass KW - density KW - leucine amino peptidases Y1 - 2020 U6 - https://doi.org/10.3389/fmicb.2019.02904 SN - 1664-302X VL - 10 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Maaß, Stefanie T1 - Blick in die Zukunft BT - wie werden sich Pflanzengemeinschaften in Brandenburg verändern? JF - Vielfalt in der Uckermark : Forschungsprojekte 2015 - 2018 Y1 - 2019 SP - 24 EP - 25 PB - oerding print GmbH CY - Braunschweig ER - TY - JOUR A1 - Maaß, Stefanie A1 - Hückelheim, Ronja A1 - Rillig, Matthias C. T1 - Collembola laterally move biochar particles JF - PLOS ONE N2 - Biochar is being discussed as a soil amendment to improve soil fertility and mitigate climate change. While biochar interactions with soil microbial biota have been frequently studied, interactions with soil mesofauna are understudied. We here present an experiment in which we tested if the collembolan Folsomia candida I) can transport biochar particles, II) if yes, how far the particles are distributed within 10 days, and III) if it shows a preference among biochars made from different feedstocks, i.e. pine wood, pine bark and spelt husks. In general, biochar particles based on pine bark and pine wood were consistently distributed significantly more than those made of spelt husks, but all types were transported more than 4cm within 10 days. Additionally, we provide evidence that biochar particles can become readily attached to the cuticle of collembolans and hence be transported, potentially even over large distances. Our study shows that the soil mesofauna can indeed act as a vector for the transport of biochar particles and show clear preferences depending on the respective feedstock, which would need to be studied in more detail in the future. Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0224179 SN - 1932-6203 VL - 14 IS - 11 PB - Public Library of Science CY - San Francisco ER -