scholarly journals Diversity of epiphytic lichens in boreo-nemoral forests on the North-Estonian limestone escarpment: the effect of tree level factors and local environmental conditions – ERRATUM

2009 ◽  
Vol 41 (2) ◽  
pp. 211-211 ◽  
Author(s):  
Inga JÜRIADO ◽  
Jaan LIIRA ◽  
Jaanus PAAL
Keyword(s):  
Environmental Conditions ◽  
Tree Level ◽  
Epiphytic Lichens ◽  
The North

Diversity of epiphytic lichens in boreo-nemoral forests on the North-Estonian limestone escarpment: the effect of tree level factors and local environmental conditions

2009 ◽  
Vol 41 (1) ◽  
pp. 81-94 ◽  
Author(s):  
Inga JÜRIADO ◽  
Jaan LIIRA ◽  
Jaanus PAAL
Keyword(s):  
Species Richness ◽  
Tree Species ◽  
Geographical Location ◽  
Tree Level ◽  
Epiphytic Lichens ◽  
Forest Fragment ◽  
Lichen Diversity ◽  
The North ◽  
Talus Slope ◽  
Study Sites

AbstractThe species richness and composition of lichens was quantified for four temperate broad-leaved tree species (Acer platanoides, Fraxinus excelsior, Tilia cordataandUlmus glabra) in boreo-nemoral forests on the talus slope of the North-Estonian limestone escarpment (North-Estonian Klint). Thirteen study sites were distributed along the klint on a west to east gradient. The effects of tree and stand characteristics and geographical location of a stand on composition and diversity of epiphytic lichens were evaluated by multivariate analyses (DCA, CCA, pCCA) and by general linear mixed models (GLMM). Tree level variables (e.g. bark pH, bryophytes cover and host tree species) explained the largest fraction of the variation in lichen species composition. However, species richness and composition were significantly influenced also by the unique habitat conditions of klint forest (length of the forest fragment, proximity of the stand to the sea and height of the escarpment). A significant correlation between stand locality and lichen diversity on the tree bole was found which is most likely related to local air pollution gradients caused by alkaline cement dust and acid pollutants in the north-eastern part of Estonia.

A reinterpretation of Scottish ‘hummocky moraine’ and its significance for the deglaciation of the Scottish Highlands during the Younger Dryas or Loch Lomond Stadial

1993 ◽  
Vol 130 (3) ◽  
pp. 301-318 ◽  
Author(s):  
Matthew R. Bennett ◽  
Geoffrey S. Boulton
Keyword(s):  
Environmental Conditions ◽  
Field Survey ◽  
Spatial Scales ◽  
Younger Dryas ◽  
North West ◽  
Scottish Highlands ◽  
Ice Cap ◽  
The North ◽  
Loch Lomond

AbstractThe aim of this paper is to demonstrate that much of the ‘hummocky moraine’ present within the northern part of the LochLomond Readvance ice cap formerly situated in the North West Scottish Highlands may be interpreted as suites of ice-front moraines deposited during active decay. These landforms can be used to reconstruct ice cap decay, whichleads to important insights into the shrinking form of the ice cap and associated environmental conditions. Evidence has been collected from 10803 airphotographs and from detailed field survey. It is presented at three spatial scales.

scholarly journals Ecological and Geographical distribution of species and genera of Primulaceae in Iraq

2014 ◽  
Vol 11 (2) ◽  
pp. 829-840
Author(s):  
Baghdad Science Journal
Keyword(s):  
Geographical Distribution ◽  
Environmental Conditions ◽  
North East ◽  
The North ◽  
East And West ◽  
Prevalent Species

The present research deal with ecological and geographical distribution of species and genera of Primulaceae in Iraq. The results were revealed that species distributed in the north , north-east and west of Iraq. Anagallis arvensis L. is the most prevalent species tolerant to different environmental conditions, while the species of Primula L. characterized as less widespread and limited in one District. In addition, the districts Rawanduz (MRO) and Sulaymaniyah (MSU) have ranked first in distribution of the species on geographical districts with (75%), while the districts southern desert (DSD) and Basra (LBA) in last place with (16.7%). Maps for geographical distribution for all species were illustrated.

Overlay-Based Middleware for the Pervasive Grid

2012 ◽  
pp. 566-588
Author(s):  
Paul Grace ◽  
Danny Hughes ◽  
Geoff Coulson ◽  
Gordon S. Blair ◽  
Barry Porter ◽  
...  
Keyword(s):  
Sensor Networks ◽  
Grid Computing ◽  
Mobile Devices ◽  
Environmental Conditions ◽  
Overlay Networks ◽  
Dynamic Adaptation ◽  
North West ◽  
The North ◽  
Flood Monitoring ◽  
Monitoring Application

Grid computing is becoming increasingly pervasive; sensor networks and mobile devices are now connected with traditional Grid infrastructure to form geographically diverse complex systems. Applications of this type can be classified as the Pervasive Grid. In this chapter we examine how traditional Grid technologies and middleware are inherently unsuited to address the challenges of extreme heterogeneity and fluctuating environmental conditions in these systems. We present Gridkit, a configurable and reconfigurable reflective middleware that leverages overlay networks and dynamic software in response to the requirements of the Pervasive Grid. We also illustrate how Gridkit has been used to deploy a flood monitoring application at a river in the north west of England; this demonstrates both the flexibility Gridkit provides, and how dynamic adaptation optimises performance and resource consumption.

Virus isolations Mosquito collections obtained during most field trips to the north-west of Western Australia have been processed for virus isolation. Until 1985, virus isolation was undertaken by intracerebral inoculation of suckling mice, but this was then replaced by cell culture using C6/36 mosquito, PSEK, BHK and Vero cells. The use of cell culture has significantly reduced the overall virus isolation rate by largely excluding arboviruses, rhabdoviruses and most bunyaviruses, but is as effective as suckling mice for the isolation of flaviviruses and alphaviruses. MVE virus has been isolated every year that significant numbers of adult mosquitoes have been processed except 1983 (Broom et al. 1989; Broom et al. 1992; Mackenzie et al. 1994c). Isolations of MVE, Kunjin and other flaviviruses are shown in Table 8.2. There was a strong correlation between the number of virus isolates in any given year and the prevailing environmental conditions. Thus those years with a heavy, above average wet season rainfall and subsequent widespread flooding yielded large numbers of virus isolates (1981, 1991, 1993) compared with years with average or below average rainfall and with only localized flooding. Although most MVE virus isolates were obtained from Culex annulirostris mosquitoes, occasional isolates were also obtained from a variety of other species, including Culex quinquefasciatus, Culex palpalis, Aedes normanensis, Aedes pseudonormanensis, Aedes eidvoldensis, Aedes tremulus, Anopheles annulipes, Anopheles bancroftii, Anopheles amictus and Mansonia uniformis (cited in Mackenzie et al. 1994b; Mackenzie and Broom 1995), although the role of these species in natural transmission cycles has still to be determined. Virus carriage rates in Culex annulirostris mosquitoes are shown in Table 8.3 for the Ord River area (Kununurra–Wyndham) and Balgo and Billiluna in south-east Kimberley. Very high mosquito infection rates were observed in those years with above average rainfall. Virus spread and persistence Stanley (1979) suggested that viraemic waterbirds, which are often nomadic, may generate epidemic activity of MVE in south-east Australia and in the Pilbara region. In an attempt to understand the genesis of epidemic activity better, our laboratory initiated a long-term study in the arid south-east Kimberley area at Billiluna and Balgo, two Aboriginal communities on the northern edge of the Great Sandy Desert. Occasional cases of Australian encephalitis had occurred in both communities (1978, 1981). The studies have clearly shown that MVE virus activity only occurs following very heavy, widespread rainfall both locally and in the catchment area of the nearby watercourse, Sturt Creek, which results in extensive flooding across its floodplain (Broom et al. 1992). Localized flooding is insufficient to generate virus activity. Two possible explanations can be proposed to account for the reappearance of MVE virus activity when environmental conditions are suitable: either virus can be reintroduced into the area by viraemic waterbirds arriving from enzootic areas further north; or virus may

1998 ◽  
pp. 133-135
Keyword(s):  
Cell Culture ◽  
Environmental Conditions ◽  
Virus Isolation ◽  
North West ◽  
Suckling Mice ◽  
The North ◽  
Virus Activity ◽  
Culex Annulirostris ◽  
Average Rainfall ◽  
Virus Isolates

scholarly journals Sympatric Atlantic puffins and razorbills show contrasting responses to adverse marine conditions during winter foraging within the North Sea

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Katie St. John Glew ◽  
Sarah Wanless ◽  
Michael P. Harris ◽  
Francis Daunt ◽  
Kjell Einar Erikstad ◽  
...  
Keyword(s):  
North Sea ◽  
Environmental Conditions ◽  
Trophic Position ◽  
Survival Rates ◽  
Sympatric Species ◽  
Ecological Niches ◽  
Overwinter Survival ◽  
The North ◽  
Winter Conditions ◽  
The North Sea

Abstract Background Natural environments are dynamic systems with conditions varying across years. Higher trophic level consumers may respond to changes in the distribution and quality of available prey by moving to locate new resources or by switching diets. In order to persist, sympatric species with similar ecological niches may show contrasting foraging responses to changes in environmental conditions. However, in marine environments this assertion remains largely untested for highly mobile predators outside the breeding season because of the challenges of quantifying foraging location and trophic position under contrasting conditions. Method Differences in overwinter survival rates of two populations of North Sea seabirds (Atlantic puffins (Fratercula arctica) and razorbills (Alca torda)) indicated that environmental conditions differed between 2007/08 (low survival and thus poor conditions) and 2014/15 (higher survival, favourable conditions). We used a combination of bird-borne data loggers and stable isotope analyses to test 1) whether these sympatric species showed consistent responses with respect to foraging location and trophic position to these contrasting winter conditions during periods when body and cheek feathers were being grown (moult) and 2) whether any observed changes in moult locations and diet could be related to the abundance and distribution of potential prey species of differing energetic quality. Results Puffins and razorbills showed divergent foraging responses to contrasting winter conditions. Puffins foraging in the North Sea used broadly similar foraging locations during moult in both winters. However, puffin diet significantly differed, with a lower average trophic position in the winter characterised by lower survival rates. By contrast, razorbills’ trophic position increased in the poor survival winter and the population foraged in more distant southerly waters of the North Sea. Conclusions Populations of North Sea puffins and razorbills showed contrasting foraging responses when environmental conditions, as indicated by overwinter survival differed. Conservation of mobile predators, many of which are in sharp decline, may benefit from dynamic spatial based management approaches focusing on behavioural changes in response to changing environmental conditions, particularly during life history stages associated with increased mortality.

Morphological evolution of the murine rodent Paraethomys in response to climatic variations (Mio-Pleistocene of North Africa)

Paleobiology ◽  
1999 ◽  
Vol 25 (3) ◽  
pp. 369-382 ◽  
Author(s):  
Sabrina Renaud ◽  
Mouloud Benammi ◽  
Jean-Jacques Jaeger
Keyword(s):  
North Africa ◽  
Environmental Conditions ◽  
Morphological Evolution ◽  
Middle Pleistocene ◽  
Metabolic Adaptation ◽  
Subsequent Increase ◽  
Evolutionary Patterns ◽  
The North ◽  
Murine Rodent ◽  
Evolutionary Response

The North African murine rodent Paraethomys evolved as an anagenetic lineage from the late Miocene until its extinction in the late—middle Pleistocene. A Fourier analysis of the outlines of the first upper and lower molars of this rodent was used to quantify the evolutionary patterns of this lineage and to compare evolutionary patterns to the climatic record. Morphological evolution and long-term environmental variations are strongly correlated. A change in molar shape, which may be related to the development of a more grass-eating diet, corresponds to the global cooling beginning around 3 Ma and the subsequent increase in aridity in North Africa. Concurrently, size increased, which may be related to increased masticatory efficiency or to metabolic adaptation to the cooler environmental conditions according to Bergmann's rule. This adaptive response to changing environmental conditions corresponds to an acceleration of evolutionary rates in the lineage. The modalities of the evolutionary response in size and shape are probably controlled by intrinsic factors such as different genetic determinisms for both characters.

Development of semi-submersible production vessels and its application to Australian waters

2008 ◽  
Vol 48 (1) ◽  
pp. 241
Author(s):  
Hilde Engelsen ◽  
Henrik Hannus
Keyword(s):  
North Sea ◽  
Environmental Conditions ◽  
Oil And Gas ◽  
Gas Production ◽  
Oil And Gas Production ◽  
The North ◽  
Hull Design ◽  
Steel Catenary Risers ◽  
Drilling Rigs ◽  
In The Beginning

Semi-submersible platforms have a long history in the North Sea. In the beginning they were used mainly as mobile offshore drilling units, but in the last two decades the permanently moored semi-submersible production vessels have become widely used both as gas processing units and combination oil and gas production vessels. The design of production semi-submersibles evolved from that of drilling rigs, but there have since been significant improvements to the design of the hull and the topside configuration in relation to operational requirements and construction processes. The design methods have also been successfully adapted to areas with different environmental conditions, in combination with steel catenary risers and polyester mooring systems. On recent designs, simplifications of the hull systems are being implemented, which ease operation and enhance the passive safety. Finally, the semi-submersible production vessel’s application to Australian waters is discussed with focus on topside layout, hull design and mooring system design. Environmental conditions offshore northwest Australia are compared to North Sea and Gulf of Mexico conditions, along with vessel class and regulatory requirements.

Methodologies for Evaluating and Qualifying External Pipeline Coatings for Northern Pipelines

2006 ◽  
Author(s):  
S. Papavinasam ◽  
A. Doiron ◽  
T. Panneerselvam ◽  
Y. Lafrenie`re ◽  
M. Attard ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Low Temperatures ◽  
Laboratory Experiments ◽  
Field Experiments ◽  
Climatic Conditions ◽  
Limited Data ◽  
The North

The design of coatings must be adequate to protect pipelines under long-term, severe environmental conditions, including the extreme climatic conditions that will apply in the North before the pipe is installed and operation begins. Practices and standardised methodologies for evaluating and qualifying pipeline coatings for application in northern pipelines are discussed. Results from laboratory and field experiments, carried out under the conditions to which coatings will be exposed during construction, are presented. Based on 1-year laboratory experiments in which samples were exposed to temperatures as low as −45°C and limited data from the field experiments, it is concluded that Canadian Standards Association (CSA) standards CSA Z662, CSA Z245.20 and CSA Z245.21 adequately cover evaluation of coatings for northern pipelines. However, in order to evaluate the effects of low-temperatures, the specimens should be exposed for at least 4 months. Coatings qualified by CSA Z245.21 (System B1 and B2) are less affected from exposure to low-temperatures than those qualified by CSA Z245.21 (System A1) and CSA Z245.20.

scholarly journals The phytosociology and syntaxonomy of relatively low-altitude areas in the North-eastern Mountain Sourveld, in the eastern Transvaal escarpment region

Koedoe ◽  
1994 ◽  
Vol 37 (2) ◽  
Author(s):  
W.S. Matthews ◽  
G.J. Bredenkamp ◽  
N. Van Rooyen
Keyword(s):  
Random Sample ◽  
Plant Communities ◽  
Environmental Conditions ◽  
Hierarchical Classification ◽  
Soil Surface ◽  
The North ◽  
North Eastern ◽  
Low Altitude

An analysis of the vegetation of the relatively low altitude regions of the North-eastern Mountain Sourveld of the eastern Transvaal escarpment is presented. Releves were compiled in 53 stratified random sample plots. ATWINSPAN-classification, refined by Braun-Blanquet procedures, revealed seven plant communities. In the hierarchical classification one class, one alliance, four associations, four subassociations and two valiants are recognised. Formal syntaxonomic descriptions of the syntaxa are given. All communities are related to specific environmental conditions, of which geology, aspect, altitude and rockiness of the soil surface are the most important.

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