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Multiproxy investigations of lacustrine sediments from Laguna Azul (52 °S) document multi-millennial Holocene influences of Southern Hemispheric Westerlies (SHW) on the hydroclimatic variability of south-eastern Patagonia. During the last 4000 years, this hydroclimatic variability is overprinted by centennial warm/dry periods. A cool/wet period from 11,600 to 10,100 cal. BP is succeeded by an early Holocene dry period (10,100–8300 cal. BP) with a shallow lake, strong anoxia, methanogenesis and high salinity. Between 8300 and 4000 cal. BP the influence of SHW weakened, resulting in a freshwater lake considered to be related to less arid conditions. Since 4000 cal. BP, regional temperature decreased accompanied by re-intensification of SHW reaching full strength since 3000 cal. BP. Centred around 2200, 1000 cal. BP and in the 20th century, Laguna Azul experienced century-long warm/dry spells. Between these dry periods, two pronounced moist periods are suggested to be contemporaneous to the ‘Dark Age Cold Period’ and the ‘Little Ice Age’. Different from millennial SHW variations, centennial fluctuations appear to be synchronous for South America and the Northern Hemisphere. Changes in solar activity, large volcanic eruptions and/or modulations of ocean circulation are potential triggers for this synchronicity.
A hydroxy-sodalite/cancrinite zeolite composite was synthesized from low-grade calcite-bearing kaolin by hydrothermal alkali-activation method at 160 C for 6 h. The effect of calcite addition on the formation of the hydroxy-sodalite/cancrinite composite was investigated
using artificial mixtures. The chemical composition and crystal morphology of the synthesized zeolite composite were characterized by X-ray powder diffraction, infrared spectroscopy, scanning electron microscopy, and N2 adsorption/desorption analyses. The average specific surface area is around 17–20 m2g-1, whereas the average pore size lies in the mesoporous range (19–21 nm). The synthesized zeolite composite was used as an adsorbent for the removal of heavy metals in aqueous solutions. Batch experiments were employed to study the influence of adsorbent dosage on heavy metal removal eciency. Results demonstrate the effective removal of significant quantities of Cu, Pb, Ni, and Zn from aqueous media. A comparative study of synthesized hydroxy-sodalite and
hydroxy-sodalite/cancrinite composites revealed the latter was 16–24% more effcient at removing heavy metals from water. The order of metal uptake effciency for these zeolites was determined to be Pb > Cu > Zn > Ni. These results indicate that zeolite composites synthesized from natural calcite-bearing kaolin materials could represent effective and low-cost adsorbents for heavy metal removal using water treatment devices in regions of water hortage.
The Müritzeum is a nature discovery centre and a museum in the heart of the Mecklenburg Lake District. It is the first natural history museum in Mecklenburg-Vorpommern, with natural history collections that are over 150 years old, and are still growing today. The collections contain about 290 000 specimens from the fields of botany, zoology and geology. An extensive library and an archive are also
part of the museum. Collecting, preserving and researching natural history are our main spheres of activity. The exhibition in the Müritzeum offers the visitor a comprehensive insight into the development of the nature and landscape of northeastern Germany and of Mecklenburg-Vorpommern and the Lake Müritz region in particular. The largest aquarium for indigenous freshwater species in Germany enables visitors to imagine themselves in the underwater world of the Mecklenburg Lake District.
Archaeological discoveries in the Tollense Valley represent remains of a Bronze Age battle of ca.1300–1250 BCE, documenting a violent group conflict hitherto unimagined for this period of time in Europe, changing the perception of the Bronze Age. Geoscientific, geoarchaeological and palaeobotanical investigations have reconstructed a tree- and shrubless mire characterised by sedges, reed and semiaquatic conditions with a shallow but wide river Tollense for the Bronze Age. The exact river
course cannot be reconstructed, but the distribution of fluvial deposits traces only a narrow corridor, in which the Tollense meandered close to the current riverbed. The initial formation of the valley mire dates to the transition from the Weichselian Late Glacial to the early Holocene.
The site at the southern shore of Krakower See shows the Quaternary geology of the surrounding
area. The local Quaternary sequence comprises a thickness of 50–100m of Quaternary deposits while
the surface morphology is dominated by the ice marginal position of the Pomeranian moraine, which
passes through the area. The bathymetry of the lake basin of Krakower See indicates a predominant
genesis by glaciofluvial erosion in combination with glacial exaration. Past research in this area has focussed
on the reconstruction of Pleniglacial to Holocene environmental changes, including lake-level
fluctuations, aeolian dynamics, and pedological processes and their modification by anthropogenic
land use.