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Results belonging to paper "High-rate biological selenate reduction in a sequencing batch reactor for recovery of hexagonal selenium".Recovery of selenium (Se) from wastewater provides a solution for both securing Se supply and preventing Se pollution. Here, we developed a high-rate process for biological selenate reduction to elemental selenium. Distinctive from other studies, we aimed for a process with selenate as the main biological electron sink, with minimal formation of methane or sulfide. A sequencing batch reactor, fed with an influent containing 120 mgSe L-1 selenate and ethanol as electron donor and carbon source, was operated for 495 days. The high rates (419 �� 17 mgSe L-1 day-1) were recorded between day 446 and day 495 for a hydraulic retention time of 6h. The maximum conversion efficiency of selenate amounted to 96% with a volumetric conversion rate of 444 mgSe L-1 day-1, which is 6 times higher than the rates reported in the literature thus far. At the end of the experiment, a highly enriched selenate reducing biomass had developed, with a specific activity of 856��26 mgSe-1day-1gbiomass-1, which was nearly 1000-fold higher than that of the inoculum. No evidence was found for the formation of methane, sulfide, or volatile reduced selenium compounds like dimethyl-selenide or H2Se, revealing a high selectivity. Ethanol was incompletely oxidized to acetate. The produced elemental selenium partially accumulated in the reactor as pure (���80% Se of the total mixture of biomass sludge flocs and flaky aggregates, and ~100% of the specific flaky aggregates) selenium black hexagonal needles, with cluster sizes between 20-200 ��m. The new process may serve as the basis for a high-rate technology to remove and recover pure selenium from wastewater or process streams with high selectivity.

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

This repository contains the dataset linked to the following publication: Article title: Synergistic effects of warming and internal nutrient loading interfere with the long-term stability of lake restoration and induce sudden re-eutrophication Journal: Environmental Science & Technology DOI: 10.1021/acs.est.2c07181 Abstract: Phosphorus (P) precipitation is among the most effective treatments to mitigate lake eutrophication. However, after a period of high effectiveness, studies have shown possible re-eutrophication and the return of harmful algal blooms. While such abrupt ecological changes were attributed to the internal P loading, the role of lake warming and its potential synergistic effects with internal loading, thus far, has been understudied. Here, in a eutrophic lake in central Germany, we quantified the driving mechanisms of the abrupt re-eutrophication and cyanobacterial blooms in 2016 (30 years after the first P precipitation). A process-based lake ecosystem model (GOTM-WET) was established using a high-frequency monitoring dataset covering contrasting trophic states. Model analyses suggested that the internal P release accounted for 68% of the cyanobacterial biomass proliferation, while lake warming contributed to 32%, including direct effects via promoting growth (18%) and synergistic effects via intensifying internal P loading (14%). The model further showed that the synergy was attributed to prolonged lake hypolimnion warming and oxygen depletion. Our study unravels the substantial role of lake warming in promoting cyanobacterial blooms in re-eutrophicated lakes. The warming effects on cyanobacteria via promoting internal loading need more attention in lake management, particularly for urban lakes. SYNOPSIS: Warming synergistically promotes re-eutrophication with internal nutrient loading and exacerbates cyanobacterial blooms in urban lakes 30 years after phosphorus mitigation. Data description by Xiangzhen Kong (xzkong@niglas.ac.cn), 2023-02-20 ---Wet chemical analysis on water samples taken at five depths (0.5, 2.5, 5.0, 7.0 and 9.0 m) from the deepest point in the lake (BA1) at biweekly intervals from 2018.5-2021.8. File name: BAB_BA1_TN_mgL.obs (total nitrogen concentration) BAB_BA1_NH4_mgL.obs (ammonium nitrogen concentration) BAB_BA1_NO3_mgL.obs (nitrate nitrogen concentration) BAB_BA1_TP_mgL.obs (total phosphorus concentration) BAB_BA1_SRP_mgL.obs (Soluble reactive phosphorus concentration) BAB_BA1_DP_mgL.obs (dissolved P concentration) BAB_BA1_DOC_mgL.obs (Dissolved organic carbon concentration) BAB_BA1_Si_mgL.obs (dissolved silicon concentration) BAB_BA1_Chla_HPLC_DIN_mgL.obs (Chl-a concentration) ---CTD probe profile data from the deepest point in the lake (BA1) from 2017.8 to 2021.8 at biweekly basis with approximately 0.1 m vertical resolution File name: t_prof_file_barleber_ctm644.obs (water temperature) oxy_prof_file_barleber_ctm644 (Dissolved oxygen) turb_prof_file_barleber_ctm644.obs (Turbidity) chla_prof_file_barleber_ctm644.obs (Chl-a concentration) ---BBE probe profile data from the deepest point in the lake (BA1) from 2017.8 to 2021.8 at biweekly basis with approximately 0.1 m vertical resolution File name: totalChla_prof_file_barleber_FP2101.obs (Chl-a concentration) bluegreen_prof_file_barleber_FP2101.obs (Blue-green algae Chl-a concentration) green_prof_file_barleber_FP2101.obs (Green algae Chl-a concentration) diatom_prof_file_barleber_FP2101.obs (Diatom Chl-a concentration)

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.

Global climate change governance has changed substantially in the last decade, with a shift in focus from negotiating globally agreed greenhouse gas (GHG) reduction targets to nationally determined contributions, as enshrined in the 2015 Paris Agreement. This paper analyses trends in adoption of national climate legislation and strategies, GHG targets, and renewable and energy efficiency targets in almost all UNFCCC Parties, focusing on the period from 2007 to 2017. The uniqueness and added value of this paper reside in its broad sweep of countries, the more than decade-long coverage and the use of objective metrics rather than normative judgements. Key results show that national climate legislation and strategies witnessed a strong increase in the first half of the assessed decade, likely due to the political lead up to the Copenhagen Climate Conference in 2009, but have somewhat stagnated in recent years, currently covering 70% of global GHG emissions (almost 50% of countries). In comparison, the coverage of GHG targets increased considerably in the run up to adoption of the Paris Agreement and 89% of global GHG emissions are currently covered by such targets. Renewable energy targets saw a steady spread, with 79% of the global GHG emissions covered in 2017 compared to 45% in 2007, with a steep increase in developing countries. Key policy insightsThe number of countries that have national legislation and strategies in place increased strongly up to 2012, but the increase has levelled off in recent years, now covering 70% of global emissions by 2017 (48% of countries and 76% of global population).Economy-wide GHG reduction targets witnessed a strong increase in the build up to 2015 and are adopted by countries covering 89% of global GHG emissions (76% not counting USA) and 90% of global population (86% not counting USA) in 2017.Renewable energy targets saw a steady increase throughout the last decade with coverage of countries in 2017 comparable to that of GHG targets.Key shifts in national measures coincide with landmark international events – an increase in legislation and strategy in the build-up to the Copenhagen Climate Conference and an increase in targets around the Paris Agreement – emphasizing the importance of the international process to maintaining national momentum. The number of countries that have national legislation and strategies in place increased strongly up to 2012, but the increase has levelled off in recent years, now covering 70% of global emissions by 2017 (48% of countries and 76% of global population). Economy-wide GHG reduction targets witnessed a strong increase in the build up to 2015 and are adopted by countries covering 89% of global GHG emissions (76% not counting USA) and 90% of global population (86% not counting USA) in 2017. Renewable energy targets saw a steady increase throughout the last decade with coverage of countries in 2017 comparable to that of GHG targets. Key shifts in national measures coincide with landmark international events – an increase in legislation and strategy in the build-up to the Copenhagen Climate Conference and an increase in targets around the Paris Agreement – emphasizing the importance of the international process to maintaining national momentum.

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"]}