Deposition of Organic Matter in the Norwegian-Greenland Sea during the Past 2.7 Million Years

1995 ◽  
Vol 44 (3) ◽  
pp. 355-366 ◽  
Author(s):  
T. Wagner ◽  
J.A. Hölemann
Tempo ◽  
2020 ◽  
Vol 75 (295) ◽  
pp. 31-44
Author(s):  
Maayan Tsadka

AbstractSonic botany is an ongoing project that I have been developing over the past few years. It incorporates natural artefacts: dry leaves, pods, flowers, branches, rocks, bones and other organic findings. These are used as musical instruments that are played on with a scientific/musical tool: tuning forks in various frequencies. The vibration from the tuning forks resonates through the natural artefacts which amplify the vibration and – via sound – reveal the texture, size, material and condition of the organic matter. This process generates new sonic material, new context and new forms of musical composition. The practice developed into several compositions and projects, a performance practice, a notation system and a way of listening. Here I share some of the insights I gained through this process, the tools and the compositional framework.


2018 ◽  
Vol 58 (4) ◽  
pp. 462-472 ◽  
Author(s):  
R. A. Chernov ◽  
A. Ya. Muraviev

Climate warming in Svalbard, starting in the 1920s, caused a signifcant reduction in the mountain glaciation of the Nordenskjold Land. Te most extensive changes took place in the Western part of this territory due to the influence of the warm Spitsbergen current creating here the high temperature background. In addition, due to elevation of the level of the climatic snow line, many glaciers have actually lost the area of accumulation. From 1936 to 2017, the area of glaciers in the Western part of this region decreased by 169.5 km2 or 49.5%. Large valley glaciers and numerous small glaciers have lost the greatest area. Te relative losses of the area of glaciers were revealed to be proportional to sizes of them. In average over the past 80 years, glaciers with areas smaller 0.5 km² reduced by 76%, while big glaciers with areas larger 5 km2 – by only 34%. At present, there are 152 glaciers with a total area of 172.73±9.31 km2 in the Western territory of the Land of Nordenskjold (West of the Bolterdalen valley). According to the aerial photography of 2008–2009, the total area of glaciation of the Land of Nordenskjold covers 428 km2. High present-day rates of the retreating of local glaciers are apparently caused by extreme thinning of glacial tongues. At the same time, shrinking of glaciers located in the West of the Peninsula turned out to be more intensive than that of glaciers in its center. Although the Eastern territories receive less precipitation than glaciers near the coast of the Greenland Sea, the Eastern glaciers were found to be more resistant to reduction due to higher locations of them.


Science ◽  
2019 ◽  
Vol 365 (6455) ◽  
pp. eaav0550 ◽  
Author(s):  
T. W. Crowther ◽  
J. van den Hoogen ◽  
J. Wan ◽  
M. A. Mayes ◽  
A. D. Keiser ◽  
...  

Soil organisms represent the most biologically diverse community on land and govern the turnover of the largest organic matter pool in the terrestrial biosphere. The highly complex nature of these communities at local scales has traditionally obscured efforts to identify unifying patterns in global soil biodiversity and biogeochemistry. As a result, environmental covariates have generally been used as a proxy to represent the variation in soil community activity in global biogeochemical models. Yet over the past decade, broad-scale studies have begun to see past this local heterogeneity to identify unifying patterns in the biomass, diversity, and composition of certain soil groups across the globe. These unifying patterns provide new insights into the fundamental distribution and dynamics of organic matter on land.


2020 ◽  
Vol 17 (23) ◽  
pp. 5883-5908
Author(s):  
André Bahr ◽  
Monika Doubrawa ◽  
Jürgen Titschack ◽  
Gregor Austermann ◽  
Andreas Koutsodendris ◽  
...  

Abstract. Cold-water corals (CWCs) constitute important deep-water ecosystems that are under increasing environmental pressure due to ocean acidification and global warming. The sensitivity of these deep-water ecosystems to environmental change is demonstrated by abundant paleorecords drilled through CWC mounds that reveal characteristic alterations between rapid formation and dormant or erosive phases. Previous studies have identified several central parameters for driving or inhibiting CWC growth such as food supply, oxygenation, and the carbon saturation state of bottom water, yet there are still large uncertainties about the relative importance of the different environmental parameters. To advance this debate we have performed a multiproxy study on a sediment core retrieved from the 25 m high Bowie Mound, located at 866 m water depth on the continental slope off southeastern Brazil, a structure built up mainly by the CWC Solenosmilia variabilis. Our results indicate a multifactorial control on CWC growth at Bowie Mound during the past ∼ 160 kyr, which reveals distinct formation pulses during northern high-latitude glacial cold events (Heinrich stadials, HSs) largely associated with anomalously strong monsoonal rainfall over the continent. The ensuing enhanced runoff elevated the terrigenous nutrient and organic-matter supply to the continental margin and likely boosted marine productivity. The dispersal of food particles towards the CWC colonies during HSs was facilitated by the highly dynamic hydraulic conditions along the continental slope that prevailed throughout glacial periods. These conditions caused the emplacement of a pronounced nepheloid layer above Bowie Mound, thereby aiding the concentration and along-slope dispersal of organic matter. Our study thus emphasizes the impact of continental climate variability on a highly vulnerable deep-marine ecosystem.


1992 ◽  
Vol 11 (1) ◽  
pp. 58-58 ◽  
Author(s):  
Henning A. Bauch

Abstract. Planktonic foraminifers from Pleistocene sediments from the Norwegian-Greenland Sea (NGS) have been subject to intense investigation during the past 20 years. This is mainly due to their almost continuous presence in glacial and interglacial times, and hence, their utility for establishing sound O18-isotopic curves. Traditionally, all are assigned to a polar and subpolar group. Neogloboquadrina pachyderma (sinistral) is the only polar species, whereas the subpolar group is made up of Globigerina quinqueloba, G. bulloides, G. universa, N. pachyderma (dextral), N. dutertrei, Globigerinita glutinata, Gl. uvula, Globorotalia inflata, Glr. truncalutinoides, Glr. scitula. N. pachyderma (sinistral) is almost continuously present during glacial/interglacial times. This is in contrast to the subpolar species that show main abundances in interglacial maxima only. Prior to this study, a species belonging to the genus Beela has never been mentioned to occur in Pleistocene sediments north of 55° latitude (Holmes, 1984). My specimens exhibit a thin-walled spinose test; trochospiral becoming streptospiral; last chamber radially elongated but never pointed or digitate; aperture very variable from small umbilical to larger extraumbilical-umbilical. Its size ranges from 200–660μm, but is mainly confined to the 250–500μm mesh-size fraction.These general characteristics agree well with the emendation of the genus Beela by Holmes (1984). Accordingly, the described species will in future be assigned to Beela megastoma (Earland).There is good evidence that Beela megastoma is not simply a ‘warmer water form’ being swept into the NGS by North Atlantic Waters as some of those mentioned above, but a species that seems to. . .


2008 ◽  
Vol 16 (6) ◽  
pp. 58-61
Author(s):  
B. L. Kirkland ◽  
F. L. Lynch ◽  
R. L. Folk ◽  
A.M. Lawrence ◽  
M.E. Corley

Tiny (50-200 nm) spheroids were first discovered by Folk through SEM work on the hot springs of Viterbo Italy. He termed these small, spherical structures “nannobacteria,” and proposed that they may be important agents in precipitation of CaCO3, as needle-like crystals of the mineral aragonite, and as bundles of such needle-like crystals (termed “fuzzy dumbbells”), or as elongated crystals of the mineral calcite.During the past 15 years, nanometer-scale spheroids have been discovered in the geological, medical, and astronomical worlds. There can be no doubt as to their existence, but their significance and origin remain a subject of continuing controversy. Even the spelling (“nanno-“), which has been the standard in biology, geology, and paleontology going back to the 19th century, has been questioned. Whether or not they are truly bacteria or any form of life has been a subject of heated debate.


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