2,838 research outputs found
Land cover maps for environmental modeling at multiple scales
As described in the ECOCHANGE proposal, Task01.02.02 “Map production and aggregation”, two major products are generated within this WP. Firstly, land cover maps at high spatial resolutions will be produced for the European Union and for the reference years of 1960, 1990 and 2000. Secondly, thematic and spatial aggregated products will be derived at coarser spatial resolutions in order to synthesize the fragmentation and variability within coarser cells for biodiversity assessment and modelling. The name of the official deliverable is D01.02.01 “Land cover maps for environmental modelling at multiple scales” and includes this report, the digital land cover products and an interactive website to view the data at all thematic and spatial scales
Permafrost, landscape and ecosystem responses to late Quaternary warm stages in Northeast Siberia
Permafrost, landscape and ecosystem responses to late Quaternary warm stages in
Northeast Siberia
S. Wetterich1, F. Kienast2, L. Schirrmeister1, M. Fritz1, A. Andreev3, P. Tarasov4
1Alfred Wegener Institute for Polar and Marine Research, Department of Periglacial Research,
Potsdam, Germany; 2Senckenberg Research Institute and Natural History Museum, Research
Station for Quaternary Palaeontology, Weimar, Germany; 3Institute of Geology and Mineralogy,
University of Cologne, Germany; 4Institute of Geological Sciences, Free University Berlin,
Germany
Perennially frozen ground is widely distributed in Arctic lowlands and beyond. Permafrost
responds sensitive to changes in climate conditions. Climate-driven dynamics of landscape,
sedimentation and ecology in periglacial regions are frequently recorded in permafrost deposits.
The study of late Quaternary permafrost can therefore reveal past glacial-interglacial and stadialinterstadial
environmental dynamics. One of the most striking processes under warming climate
conditions is the extensive thawing of permafrost (thermokarst) and subsequent surface
subsidence. Thermokarst basins promote the development of lakes, whose sedimentological and
paleontological records give insights into past interglacial and interstadial (warm).
In this paper we present results of qualitative and quantitative reconstructions of climate and
environmental conditions for the last Interglacial (MIS 5e, Kazantsevo; ca. 130 to 115 ka ago), the
lateglacial Allerød Interstadial (ca. 13 to 11 uncal. ka BP), and the early Holocene (ca. 10.5 to 8
uncal. ka BP). The study was performed in course of the IPY project #15 ‘Past Permafrost’ with
permafrost deposits exposed at the coasts of the Dmitry Laptev Strait (East Siberian Sea, East
Siberia). The reconstruction based on fossil-rich findings of plants (pollen, macro-remains) and
invertebrates (beetles, chironomids, ostracods gastropods).
Interglacial vegetation dynamics are reflected in the pollen records by changes from early
interglacial grass-sedge-tundra to shrub-tundra during the interglacial thermal optimum followed
by grass-sedge-tundra vegetation at the end of the Kazantsevo warm period. Terrestrial beetle
and plant remains prove the former existence of open forest tundra with Dahurian larch, grey
alder and boreal shrubs interspersed with patches of steppes and meadows during the
interglacial thermal optimum. Mean temperature reconstructions of the warmest month (MTWA,
TJuly) for the interglacial thermal optimum are based on quantitative chironomid transfer functions
revealed a TJuly of 12.9 ± 0.9 °C. The TJuly reconstructed by plant macrofossils amounts to 13.2 ±
0.5 °C, and the pollen-based TJuly reaches 14.3 ± 3.3 °C. Low net precipitation is reflected by
steppe plants and beetles. The temperature reconstruction based on three independent
approaches. Nethertheless, all methods consistently indicate an interglacial TJuly about 10 °C
higher than today, which is interpreted as a result of a combination of increased insolation and
higher climatic continentality during the last Interglacial.
Grass-sedge dominated tundra vegetation occurred during the lateglacial to Holocene transition
which was replaced by shrub tundra during the early Holocene. The presence of Salix and Betula
pollen reflects temperatures about 4 °C higher than present between 12 to 11 uncal. ka BP,
during the Allerød Interstadial, but shrubs disappeared in the following Younger Dryas stadial,
reflecting a climate deterioration. Alnus fruticosa, Betula nana, Poaceae and Cyperaceae
dominate early Holocene pollen spectra. Pollen-based reconstructions point to TJuly 4 °C warmer
than present. Shrubs gradually disappeared from coastal areas after 7.6 uncal. ka BP when
vegetation cover became similar to modern wet tundra.
Thermokarst acted as response to warming conditions on landscape scale in permafrost regions.
Concurrent changes in relief, hydrology and ecosystems are obvious and detectable by analyses
of the paleontological record preserved in thermokarst deposits
How do universities’ organizational characteristics, management strategies, and culture influence academic research collaboration? A literature review and research agenda
In the contemporary science and higher education system, national and supranational governments fund and foster universities to collaborate through specific funding lines and competition in World University Rankings, making it indispensable for universities to demonstrate collaboration at the organizational level. Thus, universities strive to encourage their scientific members to collaborate – and to different degrees – facilitate forms of collaboration. Questions on how universities as organizations influence academic research collaboration arise. To go beyond the existing literature, this study firstly develops an analytical two-dimensional framework organizing the literature on four levels of investigation (meta, macro, meso, micro). Based on this framework, the paper presents a literature review of the current state of the art in academic research collaboration. Secondly, the paper establishes a research agenda by synthesizing organizational influences found as organizational characteristics, management strategies, and organizational culture and presents three research avenues for future research. The paper concludes that we have only just begun to study the organizational influences of universities (especially the organizational culture) on academic research collaboration and how these organizational categories are interrelated
Structural Geology of Eastern Part of Dairy Ridge Quadrangle and Western Part of Meachum Ridge Quadrangle, Utah
A detailed geologic investigation was made of the eastern part of the Dairy Ridge Quadrangle and the western part of the Meachum Ridge Quadrangle, Utah. The area is located in north-central Utah in Rich County. It lies between lat. 41°22\u2730 N. and lat. 41° 28\u2750 N. and between long. 111° 21\u2740 W. and long. 111°25\u2715 W. The area measures 13.8 km in the north-south direction and 5.5 km in the east-west direction. It is on the eastern side of the Wasatch Range about 20 km west-southwest of Randolph, Utah.
Stratigraphic units of Precambrian to Cambrian age crop out in the western part of the area, above the Woodruff thrust fault, and dip west. These include the Precambrian Mutual Formation and the Cambrian Geertsen Canyon Quartzite. Units of Pennsylvanian to Jurassic age crop out in the eastern part of the area below the Woodruff thrust fault. They dip west and are overturned to the east. These units include the following: Pennsylvanian Weber Formation, Permian Grandeur Member of the Park City Formation, Permian Phosphoria Formation, Triassic Thaynes Limestone, Triassic Ankareh Formation, Jurassic Nugget Sandstone, and Jurassic Twin Creek Limestone. The Tertiary Wasatch Formation unconformably overlies all older units in places.
The Woodruff thrust fault is the major structural feature of the area. Quartzite of the Precambrian Mutual Formation is thrust eastward over the Pennsylvanian Weber Formation as well as over formations of Permian and Triassic ages. The Woodruff thrust fault strikes about N. 20° E. and dips 18° W. to 33° W. Stratigraphic throw is at least 5,800 m. Probable horizontal displacement is tens of kilometers. The stratigraphic units, under the thrust fault, dip west and are overturned to the east. They form the western limb of a large asymmetrical syncline. The overturned units are cut by a west-dipping high-angle thrust fault. The syncline and the thrust faults were produced by the Sevier orogeny which began in latest Jurassic or earliest Cretaceous time. Deformation may have continued into Paleocene time
Potential impacts of changing agricultural activities on scenic beauty - a prototypical technique for automated rapid assessment
As a result of the liberalisation of the agricultural market, mountain regions in Central Europe are at great risk of experiencing increasing land abandonment and spontaneous reforestation. Prior to taking measures for landscape maintenance, the ecological and landscape-aesthetic consequences of land abandonment should be analysed. This paper addresses the aesthetic component of such analyses: we investigated whether lay people perceive land abandonment and spontaneous reforestation as a loss or a gain and developed a prototypical technique for rapid aesthetic assessment of reforestation scenarios for vast regions. First, we conducted image experiments to assess the respondents' reactions to increasing levels of reforestation. Based on these experiments we concluded that a medium degree of reforestation is most desirable. Second, we analysed the relationship between scenic beauty and landscape patterns and found that landscape preference values correlate significantly with various quantitative measures of the landscape pattern (e.g., diversity and contagion indices of grey- tone and colour images). Third, we applied a GIS-assisted ‘moving- window' technique to transform spatially explicit remote-sensing data (in particular orthophotos) of a test region to spatially explicit data of landscape-pattern indices. Thanks to the significant positive correlation between pattern indices and landscape preference values, the resulting maps can preliminarily be interpreted as ‘beauty'-maps of the test-regio
Near collapse of the meridional SST gradient in the eastern equatorial Pacific during Heinrich Stadial 1
Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 28 (2013): 663–674, doi:10.1002/2013PA002499.Sea surface temperatures (SST) and inorganic continental input over the last 25,000 years (25 ka) are reconstructed in the far eastern equatorial Pacific (EEP) based on three cores stretching from the equatorial front (~0.01°N, ME0005-24JC) into the cold tongue region (~3.6°S; TR163-31P and V19-30). We revisit previously published alkenone-derived SST records for these sites and present a revised chronology for V19-30. Inorganic continental input is quantified at all three sites based on 230Th-normalized fluxes of the long-lived continental isotope thorium-232 and interpreted to be largely dust. Our data show a very weak meridional (cross-equatorial) SST gradient during Heinrich Stadial 1 (HS1, 18–15 ka B.P.) and high dust input along with peak export production at and north of the equator. These findings are corroborated by an Earth system model experiment for HS1 that simulates intensified northeasterly trade winds in the EEP, stronger equatorial upwelling, and surface cooling. Furthermore, the related southward shift of the Intertropical Convergence Zone (ITCZ) during HS1 is also indicative of drier conditions in the typical source regions for dust.This work was
supported by grants from the Canadian Foundation for Climate and Atmospheric
Sciences (CFCAS), the Canadian Institute for Advanced Research (CIFAR),
the Natural Sciences and Engineering Research Council (NSERC), Canada
and the National Science Foundation (NSF), USA. A. Timmermann and
T. Friedrich were supported by NSF grant 1010869.2014-05-2
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