Frontiers in soil ecology—Insights from the World Biodiversity Forum 2022

Global change is affecting soil biodiversity and functioning across all terrestrial ecosystems. Still, much is unknown about how soil biodiversity and function will change in the future in response to simultaneous alterations in climate and land use, as well as other environmental drivers. It is crucial to understand the direct, indirect and interactive effects of global change drivers on soil communities and ecosystems across environmental contexts, not only today but also in the near future. This is particularly relevant for international efforts to tackle climate change like the Paris Agreement, and considering the failure to achieve the 2020 biodiversity targets, especially the target of halting soil degradation. Here, we outline the main frontiers related to soil ecology that were presented and discussed at the thematic sessions of the World Biodiversity Forum 2022 in Davos, Switzerland. We highlight multiple frontiers of knowledge associated with data integration, causal inference, soil biodiversity and function scenarios, critical soil biodiversity facets, underrepresented drivers, global collaboration, knowledge application and transdisciplinarity, as well as policy and public communication. These identified research priorities are not only of immediate interest to the scientific community but may also be considered in research priority programmes and calls for funding

Frontiers in soil ecology—Insights from the World Biodiversity Forum 2022

17 páginas.- 3 figuras.- 194 referenciasGlobal change is affecting soil biodiversity and functioning across all terrestrial ecosystems. Still, much is unknown about how soil biodiversity and function will change in the future in response to simultaneous alterations in climate and land use, as well as other environmental drivers. It is crucial to understand the direct, indirect and interactive effects of global change drivers on soil communities and ecosystems across environmental contexts, not only today but also in the near future. This is particularly relevant for international efforts to tackle climate change like the Paris Agreement, and considering the failure to achieve the 2020 biodiversity targets, especially the target of halting soil degradation. Here, we outline the main frontiers related to soil ecology that were presented and discussed at the thematic sessions of the World Biodiversity Forum 2022 in Davos, Switzerland. We highlight multiple frontiers of knowledge associated with data integration, causal inference, soil biodiversity and function scenarios, critical soil biodiversity facets, underrepresented drivers, global collaboration, knowledge application and transdisciplinarity, as well as policy and public communication. These identified research priorities are not only of immediate interest to the scientific community but may also be considered in research priority programmes and calls for funding.Funding information Deutsche Forschungsgemeinschaft, Grant/Award Numbers: DFG– FZT 118, 202548816, 493345801, DFG, FOR 5000, 192626868, 326061700, MO 412/54‐2; DFG, Grant/Award Numbers: Ei 862/29‐1, Ei 862/ 31‐1; GlobNet project, Grant/Award Number: ANR‐16‐CE02‐0009; Investissement d'Avenir, Grant/Award Numbers: Trajectories: ANR‐15‐ IDEX‐02, Montane: OSUG@2020: ANR‐10‐ LAB‐56; Saxon State Ministry for Science, Culture and Tourism (SMWK), Germany, Grant/Award Number: 3‐7304/35/6‐2021/ 48880; sDiv, Grant/Award Number: SFW9.02; ERC‐StG SHIFTFEEDBACK, Grant/Award Number: 851678; European Union's Horizon 2020 research and innovation programme, Grant/Award Numbers: 864287— THRESHOLD—ERC‐2019‐COG, 817946; Swedish Research Council Formas, Grant/Award Number: 2020‐00807; German Federal Environmental Foundation, Grant/Award Number: DBU, 20021/752Peer reviewe

Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Publisher Copyright: © 2021, The Author(s).Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.Peer reviewe

Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change

Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Global maps of soil temperature.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Litter quality and its effect on litter decomposition and macro-decomposers in alpine soils

Alpines Grasland entstand durch Jahrhunderte extensiver Bewirtschaftung und beherbergt eine einzigartige Flora und Fauna, welche etliche Ökosystemleistungen bereitstellen. Jedoch werden diese seit 1950 aufgelassen, was zur Verbuschung führt und die Pflanzen- und Tiergemeinschaften erheblich beeinflusst. Ob diese Veränderungen zum beobachteten Rückgang von wichtigen Streuzersetzern wie Regenwürmer führen, ist noch unklar. Deshalb führte ich: (i) ein Streubeutel-Experiment zum besseren Verständnis von alpinen Streu-Abbauraten durch, (ii) untersuchte in Cafeteria-Fütterungsexperimente mit Regenwürmern und Doppelfüßern deren Futterpräferenzen, und (iii) testete wie die Streuqualität den Lebenszyklus von Regenwürmern beeinflusst. Die Streutypen (Strauch, Gras, Kraut) unterschieden sich signifikant in chemischer und spektraler Zusammensetzung und Abbaurate, wobei Strauchstreu von niedriger Qualität am langsamsten abgebaut wurde. Jedoch zeigten Streumischungen beschleunigte Abbauraten. Die Zersetzer zeigten eine hohe individuelle Variabilität und deshalb keine klaren Präferenzen. Regenwürmer, welche mit der Zwergstrauch- treu gefüttert wurden, benötigten am längsten zur Geschlechtsreife, produzierten die kleinste Anzahl an Kokons, aber zeigten den höchsten Schlüpferfolg. Hier konnte ich schlussendlich einen Hauptgrund für den Rückgang der Regenwürmer nach Auflassung von alpinem Grasland finden. Auch wenn diese bereitwillig die sich anhäufende Zwergstrauch-Streu verzehren, besonders wenn diese in Mischungen mit hochwertiger Grasstreu ist, hat das negative Folgen für ihre Fitness. Sie scheinen aber diese Nachteile ausgleichen zu können, indem sie vermehrt in die nächste Generation investieren.Alpine grasslands were formed by centuries of extensive management, resulting in a distinct flora and fauna providing various ecosystem services. However, abandonment has been increasing for decades, leading to shrub encroachment which significantly affects the plant and soil macro-invertebrate community. Whether these changes are responsible for the observed decline of key decomposers, mainly earthworms, is still unknown. Therefore, I conducted (i) litterbag experiments to understand alpine litter decomposition patterns, (ii) cafeteria feeding experiments (earthworms and millipedes) to investigate food preferences, and (iii) life-history experiments to test how litter quality affects earthworms. Litter (shrub, grass, forb) differed significantly in chemical and spectral composition and decomposition patterns, with low-quality shrub decomposing most slowly. However, shrub in mixtures revealed accelerated rates. Decomposers showed high individual variations and therefore no clear food preferences. Earthworms fed with shrub litter showed the longest maturation time, least cocoon numbers, but highest hatching success. Here, I was at last able to find one main reason why earthworms decline after abandonment. Although they might willingly feed on shrub litter, especially in mixtures with high-quality litter, this negatively affects most of their fitness traits. However, they seem to compensate the disadvantages by investing in the next generation.Abweichender Titel laut Übersetzung der Verfasserin/des VerfassersArbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprüftInnsbruck, Univ., Diss., 2019(VLID)336398

Consumption rates and food selectivity data from Alpine soil macro-decomposers fed on a wide range of litter types in a microcosm cafeteria experiment

Here we present data from food selectivity experiments of four abundant Alpine decomposer species (two earthworms and two millipedes). We conducted cafeteria feeding experiments in microcosms in a climate chamber offering to the specimens three representative alpine litter types of differing in litter quality (i.e. dwarf shrub, grass, and forb) as single litters and mixtures. We monitored parameters such as biomass, consumption rates (absolute and relative), and calculated from the latter food selectivity indices to investigate preferences. The tested specimens showed a high intra- and interspecific variability as they fed on all offered litter types and qualities. The epi-endogeic earthworm Lumbricus rubellus (Hoffmeister, 1843), dominant in alpine pastureland, had highest mean consumption rates (34.7 ± 24.7 mg), while Dendrobaena octaedra (Savigny, 1826), a strictly epigeic earthworm, showed considerably lower consumption rates. The tested millipedes showed similar consumption patterns, with Cylindroiulus fulviceps (Latzel, 1884) being less active than C. meinerti (Verhoeff, 1891). We found several cases where litter mixtures were preferred over single litters, including higher consumption rates of low-quality dwarf shrub litter by D. octaedra and C. meinerti when mixed with high-quality litter. Nowadays, alpine pastureland are threatened mainly by abandonment which reverted to shrubland. Our results helped us to understand that alpine soil macro-decomposer such as earthworms and millipedes are generalists feeding on a wide range of litter qualities, allowing them, in theory, to better adapt to the new evolving litter resources that become available when pastures are abandoned

Alpine soil macro-invertebrate communities from soil and litter samples from European larch and Swiss pine forests in the LTSER area “Val Mazia/Matschertal”, South Tyrol

Here we present abundance data (i.e. individuals per square metre) of soil macro-invertebrates from Alpine European larch and Swiss pine forests, as well as mixed forests. The forests are located in the LTSER area "Val Mazia/Matschertal" in the Vinschgau Valley, South Tyrol, Italy. Each three replicates from each forest type (larch, pine, and mixed) were sampled in late summer 2017. The animals were sampled with soil cores; the samples were split into soil and litter layer. Representatives of the mesofauna (i.e. Acari and Collembola) were excluded from the analyses