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Abstract Background The ascomycete fungus Podospora anserina has been appreciated for its targeted carbohydrate-active enzymatic arsenal. As a late colonizer of herbivorous dung, the fungus acts specifically on the more recalcitrant fraction of lignocellulose and this lignin-rich biotope might have resulted in the evolution of ligninolytic activities. However, the lignin-degrading abilities of the fungus have not been demonstrated by chemical analyses at the molecular level and are, thus far, solely based on genome and secretome predictions. To evaluate whether P. anserina might provide a novel source of lignin-active enzymes to tap into for potential biotechnological applications, we comprehensively mapped wheat straw lignin during fungal growth and characterized the fungal secretome. Results Quantitative 13C lignin internal standard py-GC–MS analysis showed substantial lignin removal during the 7 days of fungal growth (24% w/w), though carbohydrates were preferably targeted (58% w/w removal). Structural characterization of residual lignin by using py-GC–MS and HSQC NMR analyses demonstrated that Cα-oxidized substructures significantly increased through fungal action, while intact β-O-4′ aryl ether linkages, p-coumarate and ferulate moieties decreased, albeit to lesser extents than observed for the action of basidiomycetes. Proteomic analysis indicated that the presence of lignin induced considerable changes in the secretome of P. anserina. This was particularly reflected in a strong reduction of cellulases and galactomannanases, while H2O2-producing enzymes clearly increased. The latter enzymes, together with laccases, were likely involved in the observed ligninolysis. Conclusions For the first time, we provide unambiguous evidence for the ligninolytic activity of the ascomycete fungus P. anserina and expand the view on its enzymatic repertoire beyond carbohydrate degradation. Our results can be of significance for the development of biological lignin conversion technologies by contributing to the quest for novel lignin-active enzymes and organisms. Background The ascomycete fungus Podospora anserina has been appreciated for its targeted carbohydrate-active enzymatic arsenal. As a late colonizer of herbivorous dung, the fungus acts specifically on the more recalcitrant fraction of lignocellulose and this lignin-rich biotope might have resulted in the evolution of ligninolytic activities. However, the lignin-degrading abilities of the fungus have not been demonstrated by chemical analyses at the molecular level and are, thus far, solely based on genome and secretome predictions. To evaluate whether P. anserina might provide a novel source of lignin-active enzymes to tap into for potential biotechnological applications, we comprehensively mapped wheat straw lignin during fungal growth and characterized the fungal secretome. Results Quantitative 13C lignin internal standard py-GC–MS analysis showed substantial lignin removal during the 7 days of fungal growth (24% w/w), though carbohydrates were preferably targeted (58% w/w removal). Structural characterization of residual lignin by using py-GC–MS and HSQC NMR analyses demonstrated that Cα-oxidized substructures significantly increased through fungal action, while intact β-O-4′ aryl ether linkages, p-coumarate and ferulate moieties decreased, albeit to lesser extents than observed for the action of basidiomycetes. Proteomic analysis indicated that the presence of lignin induced considerable changes in the secretome of P. anserina. This was particularly reflected in a strong reduction of cellulases and galactomannanases, while H2O2-producing enzymes clearly increased. The latter enzymes, together with laccases, were likely involved in the observed ligninolysis. Conclusions For the first time, we provide unambiguous evidence for the ligninolytic activity of the ascomycete fungus P. anserina and expand the view on its enzymatic repertoire beyond carbohydrate degradation. Our results can be of significance for the development of biological lignin conversion technologies by contributing to the quest for novel lignin-active enzymes and organisms.

The dataset covers biotic and abiotic data from the aquatic habitat of a population of the sediment-rooted macrophyte Myriophyllum spicatum in the temperate climate region (The Netherlands). The growth of M. spicatum was monitored in 0.2025 m2 plant baskets installed in an experimental ditch. Parameters monitored included biomass (fresh and dry weight), shoot length, seasonal short-term growth rates of shoots, relevant environmental parameters and weather data. This dataset includes the 2-year experimental biotic (macrophyte biomass and growth data) and environmental data (water quality data, sediment data). A second file includes the statistical data. A third file includes the weather data.

Aromatization of furan and substituted furans over zeolite catalysts is a promising reaction to convert cellulose-derived compounds into valuable aromatic hydrocarbons and light olefins. A lack of understanding of the reaction mechanism however hinders further development of this process. Here, we propose the reaction mechanism, underlying the chemistry of furan and methanol co-aromatization over HZSM-5 zeolite catalyst. Applying 13C isotope labeling in a combination with NMR spectroscopy and high temporal resolution gas chromatography-mass spectrometry analysis, we demonstrate that aromatization of furan and methanol are not mechanistically separated and can be described within the dual-cycle hydrocarbon pool mechanism. Cofeeding furan with methanol leads to a significant enhancement of light aromatics selectivity and increased catalyst lifetime.

Nearly all major glaciers in Greenland have reduced in size over the last two decades. An increase in the amount of ice transported from the Greenland ice sheet to the oceans is predicted following an increase in Arctic air and ocean temperatures. One of the last glaciers with a floating ice shelf and draining a substantial area of the Greenland ice sheet is the Petermann glacier in North West Greenland. With two major calving events in 2010 and 2012 the extent of its floating ice shelf was reduced to only half of that prior to 2010 and since 2016 new fractures indicate a new calving event is predicted to reduce the length of the glacier by ~14 km. Multiple studies have indicated that after the major calving event of 2012 the glacier accelerated and a new increase in the velocity, possibly linked to the next calving event, has already been observed. With every part of the glacier’s ice shelf that is lost the resistive force that holds the glacier back is reduced and the amount of ice drained to the ocean increases. Losing its entire ice shelf could lead to a significant increase in the contribution of the Petermann glacier to global sea level rise as the Petermann fjord extends inlands below sea level for nearly a hundred kilometers. This study uses ice thickness and surface elevation data combined with velocity data from different sources to analyze the current and future stability of the Petermann glacier. Ice thickness and the velocity data is used as input in a fracture model in order to investigate the different contributions of stress, thinning and an increase in the availability of surface water to the depth crevasses can reach. The areas on the glacier that show locations where crevasses penetrate deep into the ice indicate that the glacier is vulnerable to fracturing in those spots. Connected weak spots might indicate further potential for future calving events. The results derived from the thickness data and the subsequent melt rates show that near the grounding line the glacier is experiencing ...

Het deelpad Aquatische Biomassa heeft een sterke internationale dimensie. Wereldwijd bestaat een groeiende belangstelling voor het aquatisch milieu (denk hierbij aan waterplanten, zoutwaterlandbouw, micro-algen en zeewieren) als leverancier van voedsel, grondstoffen en energie. Daarnaast is er grote aandacht voor watermanagement, met name gezien de problemen die zich aandienen t.a.v. de berging van regenwater en de beschikbaarheid van zoet water voor drinkwatervoorziening en de landbouw. In dit deelpad worden beide thema’s aan elkaar gekoppeld, zodat meerwaarde ontstaat voor duurzame ontwikkeling met een grote internationale uitstraling van biomassa voor grondstof- en energievoorziening

In this study, we test the effects of abiotic factors (light variation, caused by logging disturbance, and soil fertility) and biotic factors (species richness and functional trait composition) on biomass stocks (aboveground biomass, fine root biomass), SOM and productivity in a relatively monodominant Guyanese tropical rainforest. This forest grows on nutrient-poor soils and has few species that contribute most to total abundance. We therefore expected strong effects of soil fertility and species’ traits that determine resource acquisition and conservation, but not of diversity. We evaluated 6 years of data for 30 0.4-ha plots and tested hypotheses using structural equation models. Our results indicate that light availability (through disturbance) and soil fertility – especially P – strongly limit forest biomass productivity and stocks in this Guyanese forest. Low P availability may cause strong environmental filtering, which in turn results in a small set of dominant species. As a result, community trait composition but not species richness determines productivity and stocks of biomass and SOM in tropical forest on poor soils.

Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of forest-savanna boundary change over time. Using long-term inventory plots we quantify changes in above-ground biomass (AGB), vegetation structure and biodiversity over 20 years for five vegetation types (savanna, colonising forest or F1, successional monodominant forest or F2, Marantaceae forest or F3 and mixed forest or F4) along a savanna-forest transition of central Gabon, all occurring on similar soils. Additionally, we use novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences across the transition. Overall, F1 and F2 forests increased in AGB, mainly as a result of adding stems (recruitment in F1) or increased Basal Area (F2). Some plots of F3 and F4 increased in AGB while some decreased. Changes in biodiversity and species’ dominance were small. After 20 years no plot could be classified as having moved to the next stage in the succession. TLS vertical plant profiles showed very distinctive differences amongst the vegetation types. We highlight two relevant points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store important quantities of Carbon. Decades long-term monitoring is likely to be required to assess the speed of transition between vegetation types, ideally with TLS, as this provides more objective forest classifications than inventory monitoring.

This dataset includes the current version of the indicative distribution maps and profiles for Ecosystem Functional Groups - Level 3 of IUCN Global Ecosystem Typology (v2.1). Please refer to Keith et al. (2020) and Keith et al. (2022). The descriptive profiles provide brief summaries of key ecological traits and processes for each functional group of ecosystems to enable any ecosystem type to be assigned to a group. Maps are indicative of global distribution patterns and are not intended to represent fine-scale patterns. The maps show areas of the world containing major (value of 1, coloured red) or minor occurrences (value of 2, coloured yellow) of each ecosystem functional group. Minor occurrences are areas where an ecosystem functional group is scattered in patches within matrices of other ecosystem functional groups or where they occur in substantial areas, but only within a segment of a larger region. Most maps were prepared using a coarse-scale template (e.g. ecoregions), but some were compiled from higher resolution spatial data where available (see details in profiles). Higher resolution mapping is planned in future publications. We emphasise that spatial representation of Ecosystem Functional Groups does not follow higher-order groupings described in respective ecoregion classifications. Consequently, when Ecosystem Functional Groups are aggregated into functional biomes (Level 2 of the Global Ecosystem Typology), spatial patterns may differ from those of biogeographic biomes. Differences reflect the distinctions between functional and biogeographic interpretations of the term, “biome”. The PLuS Alliance supported a workshop in London to initiate development. DAK, EN, RTK, JRFP, JAR & NJM were supported by ARC Linkage Grants LP170101143 and LP180100159 and the MAVA Foundation. The IUCN Commission on Ecosystem Management supported travel for DAK to present aspects of the research to peers and stakeholders at International Congresses on Conservation Biology in 2017 and 2019, and at meetings in Africa, the middle east, and Europe. {"references": ["Keith, David et al. (Eds.) (2020) 'The IUCN Global Ecosystem Typology v2.0: Descriptive profiles for Biomes and Ecosystem Functional Groups'. The International Union for the Conservation of Nature (IUCN), Gland. DOI:10.2305/IUCN.CH.2020.13.en.", "Keith, David et al. (2022) 'A function-based typology for Earth's ecosystems'. Nature DOI:10.1038/s41586-022-05318-4"]}