Long-term carbon burial in European lakes: Analysis and estimate

Sediment accumulation in lakes provides a small but permanent carbon sink. To date, global estimates of the C cycle have barely considered variations in lake carbon burial. To improve the understanding of carbon storage in lakes this study analyzed the sedimentary record of 228 European lakes concerning long-term carbon burial and its correlation to lake and catchment properties. The results suggest that carbon mass accumulations in small lakes are significantly lower than those used for global estimates so far. On the other hand, the total surface area of small lakes has been severely underestimated. Results from calculations based on a Pareto distribution show that total lake surface is 240,000 km2 in Europe. We estimate total C burial in European lakes at 1.25 Mt yr−1. Half this storage takes place in boreal lakes of northern Europe, although they contribute up to 65% to the European lake surface. This is due to generally lower carbon burial rates in this region. Carbon mass accumulation rates increased in many lakes between 5000 to 2000 years BP. This coincides with increased clastic inputs due to land use change, i.e., increasing cropland coverage and soil erosion. On average, carbon accumulation rates are twice as high in younger sediments at 20 cm depth when compared to the long-term mean

Erosion of the Rwenzori Mountains, East Africa Rift, from in situ-produced cosmogenic 10Be

High relief and steep topography are thought to result in high erosion rates. In the Rwenzori Mountains of the Albert Rift, East Africa, where more than 3 km of relief have formed during uplift of the Rwenzori fault block, overall low denudation rates prevail. We measured in situ-derived cosmogenic denudation rates of 28.2 to 131 mm/kyr in mountainous catchments, and rates of 7.8 to 17.7 mm/kyr on the adjacent low-relief East African Plateau. These rates are roughly an order of magnitude lower than in other settings of similar relief. We present an extensive geomorphological analysis, and find that denudation rates are positively correlated with relief, hillslope gradient, and channel steepness, indicating that river incision controls erosional processes. In most upper headwater reaches above Quaternary ELA levels (>4500 m a.s.l.), glacial imprinting, inherited from several older and recent minor glaciation stages, prevails. In regions below 4500 m a.s.l., however, mild climatic conditions impede frost shattering, favor dense vegetation, and minimize bare rock areas and associated mass wasting. We conclude that erosion of the Rwenzori Mountains is significantly slower than corresponding rates in other mountains of high relief, due to a combination of factors: extremely dense mountain cloud forest vegetation, high rock strength of gneiss and amphibolite lithologies, and low internal fracturing due to the extensional tectonic setting. This specific combination, unique to this extensional tropical setting, leads to unexpected low erosion rates that cannot outpace post-Pliocene ongoing rock uplift of the Rwenzori fault block

Carbon sequestration in a large hydroelectric reservoir: An integrative seismic approach

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Hur fungerar medling vid ungdomsbrott och vilka fördelar kan medlingen ge brottsoffret, gärningspersonen och samhället?

Syftet med det här arbetet är att besvara frågeställningen: ”Hur fungerar medling vid ungdomsbrott och vilka fördelar kan medlingen ge brottsoffret, gärningspersonen och samhället?” Genom att gå på en föreläsning, läsa lånad litteratur i ämnet och intervjua tre personer har jag kommit fram till att det inte finns några större forskningsresultat, gjorda i Sverige eller Norden, som visar på vilken effekt medling kan ge. Jag har dock kunnat konstatera att effekten allt som oftast på positiv utifrån den information jag har fått fram. Förhoppningsvis kommer även den första stora forskningsrapporten att visa detsamma