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Lakes play a key role in the global carbon cycle, transporting, processing and storing organic carbon (OC) along the land‐ocean aquatic continuum. There are, however, surprisingly few complete lake OC budgets, particularly for certain lake types and geographical areas. An OC budget for Lough Feeagh (Ireland), an oligotrophic, peatland lake in a temperate oceanic location, was estimated for one year using both direct measurements and elements calculated from literature. It was constructed as a simple mass balance model that constrained the key OC processing rates. The total OC input to the lake during 2017 was estimated to be 2544 t C, of which it was estimated that 51% was imported as dissolved OC (DOC) in surface water, 4% in ground water, 1% in rainwater, and 3% was fixed in the lake as net ecosystem production. The remaining 41% was carried into the lake as particulate OC (POC) in surface water. The total C exported was estimated to be 2892 t C, of which 46% and 11% were exported as DOC and POC in the surface water outflow, respectively, 26% was deposited as sediment and 17% was mineralized and emitted as CO2 to the atmosphere. The results highlight the substantial volume of OC turned over in the lake during the study period. Moreover, it emphasizes how lakes in temperate, humic systems, common on the western edge of Europe, are important to the processing and fate of OC mobilized from their catchments. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim This paper identifies socio-economic driving forces of biodiversity change and analyses their political and economic dynamics by modelling socio-economic parts of three scenario storylines developed for the ALARM (assessing large-scale risks for biodiversity with tested methods) project. In the BAMBU (business-as-might-be-usual) scenario policy decisions already made in the European Union (EU) are implemented and enforced, but no additional measures are introduced. The GRAS (growth applied strategy) scenario describes a future world orientated towards economic growth and complete deregulation. And finally, SEDG (sustainable European development goal) is a normative scenario focusing on the achievement of sustainable development. Methods The GINFORS (global inter-industry forecasting system) model is applied to quantify the effects of different sets of policy measures representing the three scenarios. It allows investigation of the inter-relations between socio-economic driving forces and the state of the environment. Results The presented results for the 25 EU countries focus on the following variables: unemployment, material extraction, energy supply and CO2 emissions. The lowest amount of unemployment is in the SEDG scenario, where it steadily decreases from 2005 to 2020. In BAMBU it falls to a level that is also below that of 2005. In GRAS, the number of unemployed people in 2020 is clearly over the value of 2005. The development of total material extraction from 2005 to 2020 is nearly stable in BAMBU, while it clearly increases in GRAS. Only in SEDG is there a reduction in resource use. None of the scenarios achieves a substantial reduction in energy use. However, the development of CO2 emissions shows a decoupling from energy supply. For BAMBU there is a slight decline in CO2 emissions over time, for GRAS they increase but with a slightly smaller growth rate than energy supply. In SEDG the emissions are reduced. The decoupling trends can be explained by a shift to more renewable energy sources in all scenarios, with the highest share in SEDG. Main conclusions The results indicate that a growth-oriented policy design, such as presented in the GRAS scenario, is not compatible with the conservation of biodiversity. Only in the SEDG scenario do the policy measures support the idea of a sustainable development, but in some respects they are still not ambitious enough. [ABSTRACT FROM AUTHOR]

Phototrophic microbes, also known as micro‐algae, display a high abundance in many terrestrial surface soils. They contribute to atmospheric carbon dioxide fluxes through their photosynthesis, and thus regulate climate similar to plants. However, microbial photosynthesis remains overlooked in most terrestrial ecosystems. Here, we hypothesise that phototrophic microbes significantly contribute to peatland C uptake, unless environmental conditions limit their development and their photosynthetic activity.To test our hypothesis, we studied phototrophic microbial communities in five peatlands distributed along a latitudinal gradient in Europe. By means of metabarcoding, microscopy and cytometry analyses, as well as measures of photosynthesis, we investigated the diversity, absolute abundance and photosynthetic rates of the phototrophic microbial communities.We identified 351 photosynthetic prokaryotic and eukaryotic operational taxonomic units (OTUs) across the five peatlands. We found that water availability and plant composition were important determinants of the composition and the structure of phototrophic microbial communities. Despite environmental shifts in community structure and composition, we showed that microbial C fixation rates remained similar along the latitudinal gradient. Our results further revealed that phototrophic microbes accounted for approximately 10% of peatland C uptake.Synthesis. Our findings show that phototrophic microbes are extremely diverse and abundant in peatlands. While species turnover with environmental conditions, microbial photosynthesis similarly contributed to peatland C uptake at all latitudes. We estimate that phototrophic microbes take up around 75 MT CO2 per year in northern peatlands. This amount roughly equals the magnitude of projected peatland C loss due to climate warming and highlights the importance of phototrophic microbes for the peatland C cycle. [ABSTRACT FROM AUTHOR]

Examines the effects of elevated carbon dioxide concentration on stomal conductance of forest trees in Europe. Application of meta-analysis; Decrease in stomal conductance in response to growth in elevated carbon dioxide; Comparison of carbon dioxide reponse between younger and older trees.