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Incorporating Climatological Techniques To Improve Tree-Ring Site Selection In Complex TerrainWise, Erika K. 01 1900 (has links)
Dendroclimatologists often approach field work with the intent of reconstructing a particular climate variable (e.g. temperature, streamflow, precipitation). Although guidelines exist for species and site selection, isolating the signal of interest is difficult in areas with complex terrain or a lack of ideal sites. In this case study, I suggest climatological techniques for a more efficient sampling scheme and apply these techniques to identify criteria for selecting sites sensitive to winter precipitation in the north-central Rocky Mountains. These techniques include examining factors influencing the regional response of tree growth to climate by utilizing the International Tree-Ring Databank (ITRDB), using eigenvector analyses to identify modes of variability between sites, and delineating climate regions based on the variable of interest through climate regionalization. Results suggest that low- or mid-elevation Pseudotsuga menziesii sites should be targeted for maximizing the winter precipitation signal in the case study area. The season of precipitation impacting growth was found to be a major component of the overall variability between sites.
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Comparative Mitochondrial DNA Sequence Diversity in Isolated and Open Populations of Southern Flying SquirrelsCook, Melaney Birdsong 08 1900 (has links)
Three populations of Southern flying squirrels were studied in the Ouachita Mountains of Arkansas to assess the impact of population subdivision-due to island formation--on the population genetics of Glaucomys volans. One island, one mainland, and one open population were investigated. A 367 nucleotide hypervariable region of mitochondrial DNA was sequenced in individuals from each population. Individuals and populations were compared to assess relatedness. Higher sequence diversity was detected in the open and island populations. One island individual shared characters with both the island and mainland populations. Results support the hypothesis that the mainland population may have reduced gene flow. Also, the island population may have been originally founded by at least two maternal lineages.
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The Formation of Granite Magma Chambers in the Mourne Mountains, Northern Ireland / Bildandet av granitmagmakammare i Mournebergen, NordirlandBjörkgren, Maria January 2017 (has links)
The Mourne Mountains situated in County Down, Northern Ireland, mainly consists of solidified granite magma chambers that intruded ~ 56 million years ago into the surrounding greywacke. How granite magma chambers are emplaced in the crust has for years been a debate amongst scientist of volcanology, and is referred to as the ‘space problem’ debate. There are two principle theories in how the granite magma chambers in the Mourne Mountains were formed; either the magma chambers were forcefully emplaced by doming the greywacke host-rock or the magma chambers were emplaced by passively by magma filling the space over a subsiding block of host-rock. In this study rock samples from Luke’s Mt. dyke has been investigated with anisotropy of magnetic susceptibility (AMS). AMS measures the orientation of magnetic minerals in a rock sample and thereby shows the magma movement. These measurements indicated that the magma in the studied Luke’s Mt dyke flowed into the connected magma chamber and thus are a feeding ring-dyke. This implies that the granite bodies of the Mourne Mountains were emplaced by a passive process like cauldron subsidence. / Mätningar av magnetiska mineral har visat att den stelnade magman i en granitgång tillhörande Mournebergen i Nordirland en gång flödat in mot granitmagmakammarna. Med den här vetskapen kan tolkningar göras över hur de stora Mournebergen en gång formades. Sedan länge har den så kallade ’space problem’ debatten pågått bland forskare inom vulkanologi. Debatten diskuterar huruvida magma intruderar och placeras i jordskorpan. Mournebergen består huvudsakligen av granitmagmakammare som intruderat in i omkringliggande bergarten gråvacka för cirka 56 miljoner år sedan. Är magmakammarna ett resultat av deformation i omkringliggande gråvacka eller tvärtom? AMS (anisotropy of magnetic susceptibility) är en metod där magnetiska mineral och dess magnetiska susceptibilitet mäts för att ta reda på dess orientering i en stelnad magma. Vid ett pålagt magnetiskt fält kommer de magnetiska mineralen visa på en viss magnetisk susceptibilitet i olika orienteringar. Det här kan representeras som tre axlar på en ellipsoid. Axlarna på ellipsoiden ger information om hur mineralen flödat med magman. AMS-mätningar av stenprover från den studerade granitgången Luke’s Mt Dyke i Mournebergen visar på att graniterna som utgör största delen av bergen troligen är resultat av ett så kallat passivt bildande av magmakammare och därmed har omkringliggande bergarten gråvacka inte deformerats av granitmagmakammarna.
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Vliv vybraných parametrů vod na morfologii žaber sivena amerického a strukturu ichthyofauny Jizerských hor / The effect of selected parameters of stream water on gill morphology of brook charr and the structure of ichthyofauna of the Jizera MountainsHušek, Jiří January 2010 (has links)
The occurrence of ichthyofauna on the territory of the Jizera Mountains (Northern Bohemia, Czech Republic) is limited, besides other factors, by the water chemistry. pH value and pH-related concentration of inorganic monomeric aluminum (Ali) are crucial parameters of the water, determining the survival of fish in streams. Low pH and high concentrations of Ali cause severe damages to fish gills. The thesis deals with the influence of the water chemistry on distribution of ichthyofauna in the Jizera Mts and gill morphology in brook charr (Salvelinus fontinalis), a dominant fish species of the upper plateau of the mountains. The results show that the species diversity of fish in acidified streams is lower than that in streams without meaningful acidic episodes. Histopathological analyses of gills of brook charr individuals from an acidified stream confirm, that low pH values and high concentrations of Ali have a cummulative effect and lead to degenerative changes on gills. Key words: The Jizera Mountains, ichthyofauna, brook charr, gill morphology, water chemistry, toxic aluminium, acidification
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Posouzení vlivu revitalizačních opatření vybraných horských vrchovišť v povodí horní Vydry na jejich vodní režim / Assessment the effect of revitalizing measures of chosen peat bogs in the upper Vydra River basin on their water regimeDoležal, Tomáš January 2015 (has links)
Assessment the effect of revitalizing measures of chosen peat bogs in the upper Vydra River basin on their water regime Abstract: Despite a number of research projects, the influence of peat bogs on the hydrological regime remains a largely unexplored topic. In the past, several peat bogs in the Šumava National Park were exposed to a very strong anthropogenic pressure. Subsequently, revitalizing measures were applied to mitigate the impact of human interventions, to stop the degradation of these precious habitats, and to reform the disturbed peat bog water regime. This thesis is focused especially on fluctuations of water table level and on the hydrological regime in the catchments of Rokytka and Cikánský Brooks. Thesis further develops the topic solved in author's bachelor thesis called "Peat bog revitalizing measures and their effect on runoff dynamics in the Otava River headstream area." It contains experimental research of the influence of drainage canals and revitalizing measures on water table fluctuation. It also aims to identify the extent to which meteorological factors contribute to changes in groundwater level and to assess the present state of revitalization measures and their influence on the runoff regime. Key words: peat bogs, revitalizing measures, Šumava Mountains, water regime
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Projekt naučné cyklistické stezky v Novohradských horách / A Project of Educational Bike Trail in Novohradske mountainsIvančo, Tomáš January 2014 (has links)
Name A Project of Educational Bike Trail in Novohradske mountains Objective The aim of this work is to create project of Educational Bike Trail in Novohradske mountains and the associated creation of an information booklet for distribution of information centers in the region, creating web pages and also information boards via QR code. Methods In the first part of this work are collected and classified information processed form of research. There were used literature and internet resources. In the second part of the processed information is used to create information material to the cycling nature trail. This material was then validated questionnaire. Results The result of this work is to project the bike trail which includes the information brochure, the website, the trail's logo and information boards at each stop. These media contain all the educational information related to places along the route together with photographs and maps. Keywords Novohradske mountains, educational cycling, bicycle trail guide
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Využití dat DPZ pro hodnocení aktuálního stavu a vývoje smrkových porostů v Krkonoších / Remote sensing for evalution of state and development of Spruce stands condition in the Giant MountainsMusilová, Romana January 2012 (has links)
Bc. Romana Musilová: Využití dat DPZ pro hodnocení aktuálního stavu a vývoje smrkových porostů v Krkonoších Remote sensing for evaluation of state and development of Spruce stands condition in the Giant Mountains Abstract Monitoring the health status of forest areas using remote sensing methods are still under development. This master thesis focuses on the use of SPOT, Landsat, QuickBird and WorldView-2 images to evaluate condition of spruce stands in Giant Mountains National Park. For these purposes were selected vegetation indices available in the lite- rature. First satellite images were preprocessed and subsequently calculated vegetation indices. From the generally known were used Normalized Difference Vegetation Index, leaf area index and Simple Ratio. Than were calculated Green Vegetation Index and Red Green Index based on the monitoring of needles color changes. To evaluate moistu- re conditions were used indices Foliar Moisture Index and wide-band Normalized Diffe- rential Infrared Index. The goal was a comparison of the results of these indices and assessment of their applicability. Map outputs indices were compared with maps of de- foliation and mortality of coniferous stands by Ing. Milan Stoklasa. Keywords: remote sensing, Norway Spruce stands, Giant Mountains, vegetation indi- ces, SPOT,...
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Vliv vybraných fyzickogeografických faktorů na průběh akumulace a tání sněhové pokrývky / Effect of selected physical-geographical factors on the snow accumulation and snow meltPevná, Hana January 2012 (has links)
Effect of selected physical-geographical factors on the snow accumulation and snow melt Abstract: This master thesis analyzes the influence of physical-geographical factors on spatial distribution of snow water equivalent, and its evolution. In this work, emphasis is placed on describing the influence of vegetation, aspect and altitude. Measurement was carried out in experimental catchments Zlatý Brook and Bystřice River in western part of the Ore Mountains in winters 2008/2009, 2009/2010, 2010/2011 and 2011/2012. To evaluate the influence of these factors on value of snow water equivalent there was used one of the methods of multivariate statistical analysis - cluster analysis. The research shows that the greatest influence on the distribution and evolution of snow water equivalent in the experimental basins has vegetation and some dependency was proved also between the points of southern exposure. The measurement results demonstrate the suitability of cluster analysis for analyzing the data of point values of snow water equivalent. On the other hand the results showed the main limits of this method, especially the need for a large number of points with different characteristics. The results of measurements and statistical analysis are compared with results published in technical literature. Keywords: snow...
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Paleoglaciology of the Tian Shan and Altai Mountains, Central AsiaBlomdin, Robin January 2016 (has links)
The mountain-systems of Central Asia, act as barriers to atmospheric circulation patterns, which in turn impose striking climate gradients across the region. Glaciers are sensitive indicators of climate change and respond to changes in climate gradients over time by advancing during cold and wet periods and receding during warm and dry periods. The aim of this thesis is to investigate whether there are large-scale patterns in how past glaciers in the Tian Shan and the Altai Mountains of Central Asia responded to climate change. Multiple methods have been used, including: remote sensing, terrain analysis, field investigations, and cosmogenic nuclide (CN) dating. The glacial landform records indicate that the region experienced mainly alpine-style glaciations in the past. Large complexes of ice-marginal moraines in high elevation basins are evidence of outlet glaciers sourced from large valley glaciers, ice caps and ice-fields, and these moraine sequences, record the maximum extent of paleoglaciation. In the Ikh-Turgen Mountains, located in the continental, eastern Altai Mountains, deglaciation of these moraines occurred during marine oxygen isotope stage (MIS) 3 at ~45 ka. This is consistent with a colder and wetter climate during this time, inferred from ice core and lake level proxies. Another deglacial phase occurred during MIS 2 at ~23 ka, synchronous with the global Last Glacial Maximum. In the Russian Altai Mountains, lobate moraines in the Chuya Basin indicate deglaciation at ~19 ka, by a highly dynamic paleoglacier in the Chagan-Uzun catchment, which experienced surge-like behaviour. Furthermore, across the Tian Shan, an evaluation of new and existing CN glacial chronologies (25 dated moraines) indicates that only one regional glacial stage, between 15 and 28 ka (MIS 2), can be defined and spatially correlated across the region. These paleoglaciers were mainly restricted to valleys as a result of arid conditions during this time and variation in their extents is interpreted to reflect topographic modulation on regional climate. The ages of the oldest evidence for robust local glacial stages in the Tian Shan are not yet well constrained, however, moraines in the central Kyrgyz Tian Shan and the eastern Chinese Tian Shan have apparent minimum ages overlapping with MIS 5 and MIS 3 (with missing MIS 4 and 6 stages). However, different geological processes, such as inheritance and post-depositional shielding (e.g. deposition by surging glaciers or hummocky terrain deposition), have influenced the dating resolution, making several moraine ages inappropriate for regional comparison. Finally, to quantify regional patterns of paleoglaciation, the hypsometry (area-elevation distribution) of glacial landforms is used to estimate average paleo equilibrium line altitudes for the region. This analysis shows that while present-day ELAs mirror strong climate gradients, paleoglaciation patterns were characterised by more gentle ELA gradients. The paleo-ELA depressions across Central Asia were most prominent in the continental southern and eastern regions (500–700 m). Finally, the results from this thesis, show that Central Asia was repeatedly glaciated in the past, but underscore the importance of considering 1) catchment characteristics and styles of glaciation and 2) other non-climatic factors controlling glacier dynamics when interpreting CN chronologies to make paleoclimate inference. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Accepted. Paper 5: Manuscript.</p> / Central Asia Paleoglaciology Project (CAPP)
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The role of magmatism in the evolution of the Cambrian southern Oklahoma rift zone: geochemical constraints on the mafic-intermediate rocks in the Arbuckle Mountains, OKBulen, Casey L. January 1900 (has links)
Master of Science / Department of Geology / Matthew E. Brueseke / The Southern Oklahoma rift zone (SOA), which stretches from southern Oklahoma through the Texas panhandle and into Colorado and New Mexico, contains extensive bimodal mafic-silicic magmatism related to the opening of the Iapetus Ocean during the late Precambrian and early Cambrian. Within the SOA, the subsurface in and adjacent to the Arbuckle Mountains in southern Oklahoma contains thick packages of mafic to intermediate lava flows interlayered with thick, extensive rhyolite lava flows and lesser silicic intrusive bodies, which were first described during a 1982 drill test (Hamilton Brothers Turner Falls well) in the region. Well cuttings of these units were collected from that well and three others (Pan-Am Williams D-2, Pan-Am Jarman, Pan-Am Newberry). This study is focused on these mafic-intermediate lava flows, which represent an important stage in the evolution of the SOA and provide insights into the formation and tectonomagmatic evolution of the rift zone. The estimated 210,000 km[superscript]3 of mafic rocks in the SOA were extruded as a result of the break-up of Pannotia and the formation of the failed arm of a three-armed radial rift system. Samples analyzed from the wells plot as basalts to andesites on the TAS diagram of Le Bas et al (1986) and as subalkaline-alkaline basalts to andesite-trachyandesites on the Zr/TiO[subscript]2 vs. Nb/Y diagram of Winchester and Floyd (1977). They are dominantly tholeiitic on multiple discrimination diagrams including those of Miyashiro (1974) and Irvine and Baragar (1971). The lava flows contain traits common with EMI OIB coupled with upper crustal contamination, such as Zr/Nb values ranging from 8 to 10, Ba/Nb values ranging from 10 to 20, and K/Nb values ranging from 300 to 600. Chemostratigraphic comparisons between each well reveal up to five lava flow packages within the larger mafic-intermediate sequence, at least in the vicinity of the sampled wells. When compared with intrusive mafic rocks outcropped in the Wichita Mountains, the SOA lava flows display geochemical traits most similar to those of the Roosevelt Gabbros, suggesting a possible co-genetic relationship. Overall, the whole rock chemical characteristics coupled with comparisons with other large igneous provinces (Columbia River and Oregon Plateaus, East African Rift System) indicate that the SOA lava flows are the result of flood basalt volcanism.
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