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Allen, Charles Edward. "Alpine Soil Geomorphology: The Development and Characterization of Soil in the Alpine-Subalpine Zone of the Wallowa Mountains, Oregon." PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/5217.
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Alpine soils are young, poorly developed soils that occur above treeline. This study investigates soils located in the alpine-subalpine zone of the Wallowa Mountains, northeast Oregon. Parent material, topography, and vegetation are the most influential pedogenic factors in the high alpine landscape of the Wallowas. Soil samples were collected from the Eagle Cap Wilderness Area of the Wallowas at three mountain locations: Eagle Cap, Sacajawea, and Matterhorn. Catenas were studied in the Windblown and Minimum Snowcover zones to examine different pedogenic factors, according to the Synthetic Alpine Slope model. · Field and laboratory testing characterized the alpine soils as predominantly loamy-sands with weak structural development. The 1:1 water pH values range from 6.5 to 7.3, and the soil hues are lOYR and 2. SY in color. Soil classification characterized Eagle Cap soils as Andisols: Lithic and Typic Haplocryands. The Matterhorn and Sacajawea residuum was not classified. Parent material influence on soil development was more noticeable on granodiorite than basalt, reflecting the propensity of granodiorite to weather rapidly. Marble and shale sites lacked soil development. All the soils exhibited eolian influence, determined from silt mineralogy results. While this component did not dominate the soils as in other alpine areas, its presence was ·proven by quartz and feldspars in soils developed on marble and calcite in soils developed on granodiorite. Sodium fluoride (NaF) pH tests indicate that there is also a high aluminum content in the alpine soils, probably due to influx of Mazama volcanic ash. Krummholz and alpine turf increase the organic content of the soil, although soils beneath krummholz were not as deep. This is partially due to decreased snowcover, subsequent lack of moisture, and different parent material. All soils show a decrease in organic carbon with depth indicating that bioturbation was either low, or the soil recovered from the disturbance rapidly. Organocutans found on the bottom of rocks in the B horizon illustrate organic trans location. The increase in pH with depth shows the influence of surficial organic matter, translocated dusts, and ash. Nunatak and landmass influence on soil development was undetermined.
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Papanikolaou, Niki D. "Response of alpine heathland soils to environmental change and land management." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25204.
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Shrestha, Hari Ram. "Post-fire recovery of carbon and nitrogen in sub-alpine soils of South-eastern Australia /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6963.
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The forests of south-eastern Australia, having evolved in one of the most fire-prone environments in the world, are characterized by many adaptations to recovery following burning. Thus forest ecosystems are characterized by rapid regenerative capacity, from either seed or re-sprouting, and mechanisms to recover nutrients volatilized, including an abundance of N2 fixing plants in natural assemblages. Soil physical, chemical and biological properties are directly altered during fire due to heating and oxidation of soil organic matter, and after fire due to changes in heat, light and moisture inputs. In natural ecosystems, carbon (C) and nitrogen (N) lost from soil due to fires are recovered through photosynthesis and biological N2 fixation (BNF) by regenerating vegetation and soil microbes.This study investigated post-fire recovery of soil C and N in four structurally different sub-alpine plant communities (grassland, heathland, Snowgum and Alpine ash) of south-eastern Australia which were extensively burnt by landscape-scale fires in 2003. The amount and isotopic concentration of C and N in soils to a depth of 20 cm from Alpine ash forest were assessed five years after fire in 2008 and results were integrated with measurements taken immediately prior to burning (2002) and annually afterwards.
Because the historical data set, comprised of three soil samplings over the years 2002 to 2005, consisted of soil total C and N values which were determined as an adjunct to 13C and 15N isotopic studies, it was necessary to establish the accuracy of these IRMS-derived measurements prior to further analysis of the dataset. Two well-established and robust methods for determining soil C (total C by LECO and oxidizable C by the Walkley-Black method) were compared with the IRMS total C measurement in a one-off sampling to establish equivalence prior to assembling a time-course change in soil C from immediately pre-fire to five years post-fire. The LECO and IRMS dry combustion measurements were essentially the same (r2 >0.99), while soil oxidizable C recovery by the Walkley-Black method (wet digestion) was 68% compared to the LECO/IRMS measurements of total C. Thus the total C measurement derived from the much smaller sample size (approximately 15 mg) combusted during IRMS are equivalent to LECO measurement which require about 150 mg of sample.
Both total C and N in the soil of Alpine ash forests were significantly higher than soils from Snowgum, heathland and grassland communities. The ratio of soil NH4+ to NO3- concentration was greater for Alpine ash forest and Snow gum woodland but both N-fractions were similar for heathland and grassland soils. The abundance of soil 15N and 13C was significantly depleted in Alpine ash but both isotopes were enriched in the heathland compared to the other ecosystems. Abundance of both 15N and 13C increased with soil depth.
The natural abundance of 15N and 13C in the foliage of a subset of non-N2 fixing and N2 fixing plants was measured as a guide to estimate BNF inputs. Foliage N concentration was significantly greater in N2 fixers than non-N2 fixers while C content and 13C abundance were similar in both functional groups. Abundance of 15N was depleted in the N2 fixing species but was not significantly different from the non-N2 fixers to confidently calculate BNF inputs based on the 15N abundance in the leaves.
The total C pool in soil (to 20 cm depth) had not yet returned to the pre-fire levels in 2008 and it was estimated that such levels of C would be reached in another 6-7 years (about 12 years after the fire). The C and N of soil organic matter were significantly enriched in 15N and 13C isotopes after fire and had not returned to the pre-fire levels five years after the fire. It is concluded that the soil organic N pool can recover faster than the total C pool after the fire in the Alpine ash forests.
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Peacock, Simon. "Sulphur dynamics of the alpine soils in a Scottish catchment at risk from acidification." Thesis, University of Aberdeen, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270744.
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The adsorption of sulphate has been studied using alpine and sub-alpine podzolic soils from the Allt a'Mharcaidh catchment, Cairngorms, Scotland, U.K. A detailed investigation of sulphur pools and mechanisms of sulphur retention has revealed that incoming sulphate ion, both marine and anthropogenic, is being retained by a range of adsorption mechanisms. Analysis of the soils has indicated that the sulphur content of the soils is dominated by organic forms of sulphur. Selective chemical fractionation techniques have identified an accumulation of sesquioxides, dominated by amorphous aluminium, in the basal horizons of all the soil profiles. Adsorption of sulphate has been shown to be mainly governed by the quantity and variable charge character of this sesquioxide phase. Fractionation has also suggested that the sesquioxides in the basal horizons of the soils are dominated by a combination of gibbsitic and imogolitic materials, the latter being present as a result of podzolization processes. The generation of sulphate adsorption isotherms has revealed that the organic horizons of the catchment soils show little or no sulphate adsorption capacity, due to a small sesquioxide content. In contrast, the mineral horizons are all capable of adsorbing sulphate, and in most cases this adsorption can be modelled to the Langmuir adsorption equation. The adsorption capacity of particle size fractions of the soils has revealed that even soil particles > 1 mm show an ability to retain sulphate, possibly by physical entrapment of soil solution in mineral pores or amorphous silica gel coatings. The accompanying hydroxyl release that is generally assumed to accompany adsorption of sulphate in the mineral soils was not evident, and unless a ligand exchange reaction was masked by other chemical reactions involving total proton balance, sulphate adsorption in the catchment soils is not due to a specific or 'low affinity' specific mechanism.
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Wu, Ronggui. "The effect of land use on soil fertility and phosphorus dynamics in sub-alpine grassland soils of Gansu, China." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ63939.pdf.
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Squires, Carolyn. "An Assessment of Trampling Impact on Alpine Vegetation, Fiordland and Mount Aspiring National Parks, New Zealand." Thesis, University of Canterbury. Environmental Science, 2007. http://hdl.handle.net/10092/1494.
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The objectives of this study were two fold. The first was to quantify the nature and extent of current levels of human impact in alpine areas at four sites within Fiordland and Mount Aspiring National Parks along walking tracks at Key Summit, Gertrude Saddle, Borland Saddle and Sugarloaf Pass. In order to do so, a survey was carried out with transects placed perpendicular to the track, and distributed among different vegetation types. In each transect, plant structural and compositional aspects, and soil and environmental parameters were measured. Transects were divided into track, transition, undisturbed and control zones, and changes to dependent variables were compared with distance from the track centre. Damage from visitor impact was largely restricted to within 1m from the track centre. The most significant impacts were to structural aspects of plant and soil properties with significant reductions in plant height, total vegetation cover and bryophyte cover, and increases in bareground and erosion on tracks. Erosion was more prevalent on slopes greater than 25°, while tracks on peat soils contained greater bareground exposure, particularly of organic soil. The second study objective was to investigate the relationship between specific levels of impact and the resulting damage to two key alpine vegetation types, tussock herb field and cushion bog. This was undertaken by carrying out controlled trampling experiments, measuring changes to plant structural and compositional aspects four weeks and one year after treatment. Both vegetation types saw dramatic reductions in total vegetation cover and height immediately after trampling, however overall composition and species richness varied little. These two alpine vegetation types showed moderate-low resistance to initial impact and low resilience, with very little recovery evident one year later. Research intothese two areas is important for managing visitor use within alpine areas in order to meet conservation and recreation goals. The survey indicates that alpine community types are very sensitive to visitor use, showing significant structural damage, however the spatial extent of impact is limited within the broader landscape. Instead, visitor impacts associated with tracks are likely to be more visually and aesthetically significant, influencing the visitor experience. The trampling experiments indicate that use levels over 25-75 passes per year within tussock herbfield and cushion bog vegetation on peat soils will result in ongoing damage to previously undisturbed sites. Methods for minimising impacts include limiting visitor numbers, public education in low impact practices, redirection of tracks and use to areas that are less sensitive, the dispersal of visitor activity at very low use intensities (less than 75 direct passes per year) and the concentration of activity on tracks above this level.
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Jenkins, Meaghan Edith Biological Earth & Environmental Sciences Faculty of Science UNSW. "Carbon cycling in sub-alpine ecosystems." Awarded by:University of New South Wales. Biological, Earth & Environmental Sciences, 2009. http://handle.unsw.edu.au/1959.4/44822.
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The relationship between temperature and soil respiration has been well explored although uncertainties remain. This thesis examined the relationship between temperature and rates of heterotrophic respiration in soils from three adjacent sub-alpine Australian vegetation types; woodland, shrubland and grassland. Temperature sensitivity of soil (Q10) has recently been a hotly debate topic, one side concluding that decomposition of recalcitrant, less labile components of soil organic matter are insensitive to temperature. Whilst others argue that there is no difference in the temperature sensitivities of labile and recalcitrant carbon pools. Robust modeling of rates of soil respiration requires characterization of the temperature response of both labile and recalcitrant pools. Laboratory incubation provides a means of characterizing the temperature response of rates of respiration whilst reducing the confounding effects encountered in the field, such as seasonal fluctuations in temperature, moisture and substrate supply. I used a novel system that allowed laboratory measurement of gas exchange in soils over a range of temperatures under controlled conditions. Measurements included CO2 efflux and O2 uptake over a range of temperatures from 5 to 40oC, characterization of temperature response and sensitivity, and respiratory quotients. Rates of heterotrophic respiration fitted both exponential and Arrhenius functions and temperature sensitivity varied and depended on the model used, vegetation type and depth in the soil profile. Long-term incubation indicated both labile and resistant pools of carbon had similar temperature sensitivities. Respiratory quotients provided a strongly predictive measure of the potential rate of decomposition of soil C, independent of the temperature response of respiration, providing a tool that may be used alongside derived parameters to help understand shifts in microbial use of C substrates. Vegetation type influenced soil chemical properties and rates of heterotrophic respiration. Rates of respiration correlated well with concentrations of carbon and nitrogen as has been previously observed, unlike previous studies however a positive correlation was observed between indices of plant available phosphorus and respiration. The soils examined were from three adjacent vegetation types formed on common geology, I concluded that vegetation type had a significant influence on soil, in contrast to the commonly held view by ecologists that soil type drives patterns in vegetation. Climatic effects such as longer, dryer hotter summer, reduced snow cover and increased incidence of extreme weather events such as frosts and bushfire are likely to drive patterns in vegetation in this region and therefore have a significant impact on carbon cycling in Sub-alpine Australian soils.
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Mustafa, Tarfa. "Vers une comparaison métatranscriptomique entre deux sols alpins sous couvert nival contrasté." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENS020/document.
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La distribution de la neige à l'échelle du paysage dans les zones alpines est une des variables les plus importantes contrôlant la structure et la fonction des écosystèmes de montagne. Des changements d'épaisseur neigeuse et de durée d'enneigement peuvent entraîner de grands changements dans les conditions édapho-climatiques, ainsi que dans la composition des communautés végétales et surtout sur les cycles biogéochimiques majeurs et par conséquence la structure et le fonctionnement de l'écosystème. Nous avons utilisé l'approche métatranscriptomique pour essayer de comprendre la diversité fonctionnelle réelle et les activités exprimées dans les sols alpins par les micro-organismes, en réponse à différentes contraintes environnementales. La transcriptomique, et par extension, la métatranscriptomique, peut être vue comme l'analyse quantitative complète de tous les gènes exprimés par un ou plusieurs organismes, ou par l'écosystème entier. L'utilisation de cette approche implique d'abord l'extraction des ARN une bonne qualité et avec un bon rendement, ensuite la conversion de ces ARN en cDNA en ciblant les fractions de ARNm. La capacité d'évaluer le metatranscriptome des communautés microbiennes complexes dans différentes conditions environnementales représente en soi une avancée significative dans notre capacité de relier la structure et les fonctions des communautés avec les génotypes d'ADN (les séquences) et avec la correspondance phénotype. Dans cette étude, nous présentons l'utilisation pour la première fois de l'approche métatranscriptomique concernant les activités des communautés microbiennes des eucaryotes des sols alpins sous deux conditions d'enneigement très contrasté nommés LSM (lately snowmelt) et ESM (early snowmelt), qui sont caractérisés par des gradients climatiques contrastés et des différences de végétations associées. Nous présentons également une analyse des séquences et des procédures d'annotation en utilisant des logiciels publiquement disponibles et des scripts de python en utilisant l'environnent d'Obitools. Nous avons également développé un pipeline d'analyse bio-informatique adapté qui permet d'extraire correctement des renseignements fonctionnels et taxinomiques de ces bases de donnéesThe distribution of snow across the landscape in the Alps is one of the most important variables controlling the structure and function of mountain ecosystems. Changes in snow depth and duration can cause major changes in soil and climatic conditions, as well as the composition of plant communities and especially on the major biogeochemical cycles and consequently the structure and functioning of the ecosystem. We used the approach métatranscriptomique to try to understand the functional diversity and real activity expressed in Alpine soils by micro-organisms in response to different environmental constraints. Transcriptomics, and by extension, the métatranscriptomique, can be seen as full quantitative analysis of all genes expressed by one or more agencies or by the entire ecosystem. Using this approach involves first extracting RNA in good quality and good yield, then the conversion of RNA into cDNA by targeting mRNA fractions. The ability to assess metatranscriptome complex microbial communities under different environmental conditions is in itself a significant advance in our ability to link the structure and functions of communities with the genotypes of DNA (the sequence) and phenotype correspondence. In this study, we present the first use of the approach métatranscriptomique on the activities of eukaryotic microbial communities of alpine soil in two very contrasting locations called LSM (Lately snowmelt) and ESM (early snowmelt) which are characterized by contrasting climatic gradients and differences in vegetation associated. We present an analysis of sequences and annotation procedures using publicly available software and scripts using python programs and Obitools. We have also developed a pipeline of bioinformatics analysis adapted to correct extraction of information of the functional and taxonomic databases
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Liptzin, Daniel. "Soil nutrients and biogeochemical cycling in the forest-alpine tundra ecotone." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273655.
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Shahnavaz, Bahar. "Communautés bactériennes de sols alpins et filtres environnementaux." Grenoble 1, 2009. http://www.theses.fr/2009GRE10331.
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Les bactéri es jouent un rôle clé dans les cycles biogéochimiques. Bien que l'effet du manteau neigeux en hiver dans la fonction et la composition des communautés bactériennes du sol ait été signalé, l'effet de la variation spatio-temporelle du manteau neigeux reste à étudier. Dans cette étude, nous avons caractérisé la dynamique spatio-temporelle des communautés bactériennes à partir de deux sites extrêmes selon un gradient de couvert neigeux. Pour cela, nous avons utilisé des approches moléculaires (SSCP et clonage / séquençage) et traditionnel (isolation par culture bactérienne). Les résultats présentés montrent que l'ensemble de la diversité bactérienne, sa composition et sa structure phylogénétique sont fortement liés à la durée de la couverture de neige. En outre, ces effets sont détectables au cours de la saison de végétation des plantes. Les facteurs biotiques et abiotiques (i. E. La sénescence des plantes et le pH du sol) jouent un rôle essentiel conduisant au regroupement de certaines bactéries en clades spécifiques (Acidobactéries, Actinobactéries, α-et β-Proteobactéries). Au cours de la saison de végétation des plantes, les clades de bactéries sont plus dispersés. La présente étude montre que, à un niveau taxonomique fin, la variation temporelle est un facteur plus important que la variation spatiale sur la diversité bactérienne. A un niveau taxonomique supérieur (i. E. Sousphylum), la conclusion est inverse. Seule une petite fraction du total de la diversité bactérienne est cultivable et il se peut que certains groupes bactériens soient surreprésentés dans les plaques de culture. Cette étude apporte un nouvel éclairage sur le rôle de l’hiver et de la couverture neigeuse dans les distributions des communautés bactériennes. Cette étude peut-être utile pour prédire le comportement des bactéries dans les cycles des éléments nutritifs dans un contexte de réchauffement de la planèteBacteria play a key role in biogeochemical cycles. While the effect of winter snow cover in function and composition of soil bacterial communities has been reported, the effect of spatiotemporal variation of snow cover remains to be studied. In this study, we characterised the spatio-temporal dynamics of bacterial communities from two sites at the extremes of a snow cover gradient. We used molecular (SSCP and cloning/sequencing) and traditional (bacterial isolation by culture) approaches. The presented results show that the overall bacterial diversity, composition and phylogenetic structure are strongly related to snow cover duration. Moreover, these effects are also detectable during the plant productive season. The biotic and abiotic factors (i. E. Plant senescence and soil pH) play an essential role leading to the clustering of certain bacterial clades (Acidobacteria, Actinobacteria, α- and β-Proteobacteria). During the plant productive season, the bacterial clades are overdispersed. The preset study shows that, at a fine taxonomic level, the temporal variation is more important than the change over space. At higher taxonomic levels (i. E. Sub-phylum), the space are more important than temporal variations. Only a minor fraction of the total bacterial diversity is cultivable, and may bacterial groups be overrepresented in culture plates. This study provides new insights in role of snow cover in bacterial communities’ distribution and role of winter. This study may be useful in predicting of bacterial behaviour in nutrient cycle in a context of global warming
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Hassid, Jérôme. "Alpage, boue et eau en montagne : Les enjeux de la végétalisation des pistes de ski dans les stations alpines." Lyon, Ecole normale supérieure, 2006. http://www.theses.fr/2006ENSF0025.
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C'est sur les pistes de ski des stations alpines que la végétalisation, et la valorisation des boues d'épuration, sont étudiées. Ces deux techniques sont nos outils méthodologiques. Elles permettent d'analyser un système complexe où s'imbriquent des éléments de l'ordre du social et de l'ordre de la nature. La première partie développe les aspects sociaux. Les acteurs (élus, agriculteurs, directeurs des pistes, services déconcentrés de l'état. . . ) sont invités à expliquer les éléments nécessaires à la bonne valorisation des composts de boue pour la végétalisation des pistes de ski. Aux incertitudes scientifiques et réglementaires s'ajoute le manque d'informations d'un certain nombre d'acteurs. La deuxième partie est un travail de synthèse visant à dresser l'inventaire des pratiques de la végétalisation dans les stations alpines et à faire l'état des connaissances de leur impact sur l'environnement. La troisième partie traite les aspects physico-chimiques, principalement le suivi de l'érosion, ainsi que celui du transfert de polluants dans les hydrosystèmes. Les résultats montrent que les travaux de terrassement, ainsi que certaines pratiques de végétalisation (épandage de compost de boue en automne) peuvent entraîner des transferts importants d'Eléments Traces Métalliques (ETM) dans les eaux superficielles, notamment lors de la période critique de la fonte des neiges. La quatrième partie permet de repenser la végétalisation des pistes de ski à partir des données existantes, et des données obtenues au cours de nos travaux de recherche fondamentale. Cette partie, adoptant le registre de la recherche appliquée, débouche sur des recommandations à l'attention des aménageurs de pistes de ski. Elle propose également une analyse prospective quant à l'évolution des techniques de la végétalisation qui sont au coeur de la problématique nature/cultureThe managment of the revegetation of alpine ski resorts, and the investigation of the use of sewage waste as a fertiliser provides an important case study that allows the complex interactions between social and natural elements to be considered. This thesis focuses first on the key social elements. By considering the views of the key social actors (elected officials, farmers, ski slope managers and state run services) an impression of the different opinions on the management of ski slope revegetation was achieved. This research revealed not only irregularities in science and regulations but a considerable lack of knowledge regarding many of the actors. A second section provides a synthesis of revegetation practices currently applied to alpine ski slopes as well as their impact on the environment whilst the third focussed on the physical and chemical impacts. This third section focuses for the most part on soil erosion and the transfer of polluants to the hydrosphère. In this section it is shown that practices such as terracing and some approaches to revegetation (such as autumn fertiliser spreading) lead to significant transfer of heavy metals to surface waters, particularly during snow melt periods. The final section focuses on the practical applications of the research for the management of ski slope revegetation. It combines existing an newly collected data to provide recommandations to ski slope planner. It also presents the results of a forecast analysis of revegetation practices providing predictions to inform discussion at the center of the nature culture debate
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Zinger, Lucie. "Variations spatio-temporelles de la microflore des sols alpins." Université Joseph Fourier (Grenoble), 2009. http://www.theses.fr/2009GRE10122.
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Les micro-organismes jouent un rôle crucial dans les processus écosystémiques. L'étude de la distribution spatio-temporelle des communautés microbiennes est donc nécessaire, particulièrement dans un contexte de changements globaux. Les micro-organismes étant très diversifiés et majoritairement non cultivables, l'étude de leur diversité et des facteurs responsables de l'assemblage des communautés nécessite des outils adaptés. Les écosystèmes alpins montrent de forts gradients mésotopographiques et de régimes d'enneigements. Ces gradients engendrent une hétérogénéité spatiale du couvert végétal et des processus écosystémiques à des échelles réduites. Les contrastes de l'étage alpin s'appliquent aussi dans le temps, ceux-ci étant soumis à des froids intenses en hiver. Ces écosystèmes sont donc un modèle de choix pour l'étude des patrons spatio-temporels de la microflore du sol. Ce travail s'est d'abord concentré sur l'optimisation d'une technique d'empreinte moléculaire, la CESSCP, mais aussi d'outils statistiques pour l'analyse de séquences d'ADN. Les communautés bactériennes, fongiques et crenarchaeotes du sol ont été suivies deux années, par CE-SSCP et clonage/séquençage, dans deux habitats contrastés par leurs régimes d'enneigements. Cette étude a ensuite été étendue à l'échelle du paysage, sous divers couverts végétaux. Ce travail montre que l'assemblage des communautés microbiennes alpines varie au cours des saisons et que l'hiver constituent un fort évènement sélectif. Cette étude montre également que les communautés microbiennes sont spatialement distribuées en fonction des régimes d'enneigements et de la végétation. Les facteurs directement responsables de tels patrons sont discutésMicroorganisms play a crucial role in ecosystem processes. Understanding the spatio-temporal distribution of microbial communities is thus a central issue, especially in a context of global changes. Microorganisms are largely diverse, but given that the great part of them is still uncultured, the use of suitable tools is required to evaluate their huge diversity and the factors responsible for the community assembly. Alpine ecosystems display strong mesotopographical and snow cover regime gradients. These environmental gradients create a strong spatial heterogeneity in plant cover and ecosystem processes at reduced scales. Alpine tundra are also submitted to strong temporal contrasts, due the very low temperatures occurring during winter. These ecosystems are thus well suited to study the dynamic and spatial patterns of soil microbial communities. This work first focused on the improvement of a molecular fingerprint technique, CE-SSCP, but also on the development of statistical tools for the analysis of DNA sequences. Soil bacterial, fungal and crenarchaeal communities were followed up over two years by using CESSCP and cloning/sequencing, in two habitats contrasted by their snow cover regimes. This study was then extended at the landscape scale, under different plant covers. This work shows that microbial communities' assembly in alpine soils varies throughout seasons and that winter conditions constitute a strong selective event. This study also shows that microbial communities are spatially distributed according to snow cover regimes and plant cover. The factors directly involved in such patterns are discussed
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Kaisheva, Maria V. "The effect of metals and soil pH on the growth of Rhododendron and other alpine plants in limestone soil." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/2606.
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Rhododendrons are economically important plants in horticulture, and many species are threatened in the wild by habitat degradation. It is therefore doubly important that their nutritional needs should be understood.
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Westbrook, Matthew R. "Local scale forest encroachment into alpine habitat: past patterns and future predictions." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1396530374.
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Bressan, Nicola. "Spatial and temporal analysis of soil moisture patterns in an Alpine site in north Italy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Soil moisture represents a crucial factor in the mass and energy exchanges between land and atmosphere. Thus, the knowledge of its spatial and temporal dynamic is fundamental for several hydrological, agricultural and climatological applications.
The purpose of this study is to shed light on soil moisture patterns at catchment scale in alpine environment with focus on the role of climate, soil and topography. For this purpose, a dataset of 13 measurement points at two different depths for two years have been assessed.
The analyses highlight significant differences in soil moisture at 5 and 20 cm, showing diverse influence of climate, topography and soil type on the two.
We found that climate factors in the shallow layer contribute to 75% of the soil moisture variance and only 25% is related to topography and soil. On the other hand, at 20 cm the climatic and the time-invariant components (topography, soil, etc…) have almost equal weights in determining soil moisture spatial variance.
The analysis on seasonal basis showed the presence of frozen-related phenomena during the winter season, which prevented a clear understanding of the diverse factors on the soil moisture spatial distribution and opened new potential researches on this topic. By contrast, during the summer season well-defined soil moisture patterns mainly controlled by climate and land use were observed.
The presence of weak correlations with land data and high covariances during dry periods confirms that soil moisture is the result of an interaction of multiple components rather than the result of single controlling factor.
The study extends the knowledge of soil moisture dynamic in alpine environment, confirming some outcomes found in previous studies and providing new evidences on site dependency.
Moreover, a database for further hydrological researches, as well as practices for future surveys, have been settled.
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Meier, Courtney L. "Effects of alpine plant species on soil carbon and nitrogen dynamics and neighboring plant growth." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3303852.
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Glenn, Steven W. "Alpine Biological Soil Crusts in theWashington North Cascades| a Distribution Study at Select Sites Across a Precipitation Gradient." Thesis, Prescott College, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3712344.
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One of the least researched phenomena within the alpine regions of mountain biomes is the combination of primitive plants, algae, fungi, and lichens that are generally referred to as biological soil crusts. Sites containing well-developed biological soil crusts were examined in a variety of alpine, non-forested, vegetated landscapes in the North Cascade Mountains of Washington, USA. For each site, data were recorded for percent ground cover of biological soil crusts, slope aspect, and slope gradient of the terrain where the crust communities were located. For all of the sites, biological soil crusts were common, with a percent ground cover median of 29% and a range of 11% to 73%. The arrangement of the biological soil crusts on all sites was quite similar: all were clumped, as opposed to single, and random, as opposed to uniform. All of the soil crusts were found on soil exposed to direct sunlight. Few, if any, crusts were found in the shade of heavy forbs, or forest, or under accumulations of organic litter. When biological soil crusts were found associated with higher-order vegetation, it was with sparse graminoids, ericaceous woody shrubs, and stunted or krummholz Pinaceae trees. The biological soil crusts from this study exist on all locally undisturbed soil slope-gradients from 0% to almost 100%, and occurred on all aspects except for those in the Southwest quadrant. This study contains an extended literature review for desert and high latitude circumpolar crusts, as well as alpine biological soil crusts. Studies of biological soil crusts in subalpine and alpine environments are not common; it is hoped that this study will stimulate more research interest in these often overlooked pioneer biotic communities.
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Criscuoli, Irene. "Stabilité du charbon végétal (biochar) dans le sol et impact sur la productivité et les cycles des nutriments des prairies alpines." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066574/document.
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Le charbon de bois (biochar), est un amendement qui améliore les propriétés physico-chimiques du sol, augmente le stockage du carbone et les productions agricoles. Les anciens sites de production de charbon permettent d'évaluer son impact directement sur le terrain et sur le long terme. Dans les Alpes italiennes on a échantillonné une série de charbonnières daté de 1858 ainsi que les sols de prairies adjacents, ne contenant pas de charbon. 80±21% du carbone provenant de la production du charbon est toujours présent dans le sol et a un temps de résidence moyen de 650±139 ans. Le contenu des nutriments et leur biodisponibilité sont plus élevés dans les charbonnières par rapport à la prairie alentour et, sont plus élevés aujourd'hui qu'en 1858. L'ajout de charbon apporte des nutriments au sol, mais à court terme les ions Ca2+, K+, SO42- et Mg2+ sont lixiviés sous forme de cendres. Le charbon s'avère capable de retenir les dépositions atmosphériques de PO43-, NH4+, NO3- et, sur le long terme, de K+. L'augmentation du contenu en nutriments, la diminution de l'hydrophobie et de la densité apparente du sol augmentent la productivité et la valeur nutritionnelle des espèces alpines fourragères (Festuca nugrescens Lam. et Trifolium pratense L.). La croissance des plantes est limitée par l'azote sur les charbonnière et par le phosphore dans les prairies non-amendés ou amendés récemment. Nous concluons que le charbon/biochar peut être une stratégie pour stocker le carbone dans les sols, augmenter la production de biomasse et la qualité du fourrage des prairies Alpines à long terme. Toutefois les opérations d'enfouissement peuvent être complexes à cause de la géomorphologie des AlpesCharcoal or biochar is proposed as a soil amendment to improve physio-chemical soil properties, increase soil carbon (C) stocks and agricultural yields. Ancient charcoal hearths provide an opportunity to investigate its impact under field conditions and in the long term. A series of charcoal hearths and adjacent charcoal-free soils under grassland in the Italian Alps abandoned in 1858 was sampled.80±21% of the C originating from ancient charcoal is still present in the soil today and has a Mean Residence Time of 650±139 years. The content of total and available nutrients is higher in the hearths soils compared to the surrounding grasslands and it is higher today compared to 1858. The input of charcoal directly adds nutrients to soils but Ca2+, K+, SO42- and Mg2+ are leached in the short term after application, as they are lost in the form of ashes. Charcoal is able to retain atmospheric depositions of PO43-, NH4+, NO3- and in the long term K+.The increase in soil nutrient content and decreases in hydrophobicity and bulk density translated into higher plant growth and nutritional values of two alpine fodder species (Festuca nigrescens Lam. and Trifolium pratense L.). Plant growth was N-limited in the charcoal hearths soils and P-limited in the surrounding grasslands not amended or recently amended with charcoal/biochar.We can conclude that charcoal/biochar is a long term strategy to store carbon in soils, improve biomass productivity and fodder quality in alpine grasslands. However charcoal/biochar incorporation into soil can be complex because of the geomorphology of the Alps
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Defossez, Emmanuel. "Effets des interactions biotiques sur la régénération des forêts le long de gradients climatiques." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00947800.
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Comprendre comment les variations du climat pourraient influencer le recrutement des arbres en forêt est un défi car la germination, la croissance et la survie des semis sont particulièrement sensibles aux facteurs biotiques et abiotiques. Plusieurs modèles conceptuels généraux, (la " stress gradient hypothesis " SGH et " latitudinal herbivory theory " LHT,) suggèrent que la nature et l'intensité des interactions biotiques varient le long de gradients environnementaux. Ces modèles constituent une base théorique utile pour déterminer le rôle des interactions biotiques dans la réponse des communautés végétales aux variations du climat. Cependant, les études portant sur la SGH se sont limitées aux interactions directes entre plantes et ont négligé les interactions complexes. Les théories développées pour des niveaux trophiques supérieurs (comme la LHT) sont quant-à elles sujettes à débat et ne considèrent qu'un nombre limité d'interactions. Les interactions avec les micro-organismes du sol ont par exemple été négligées. Dans cette thèse, j'ai analysé comment les interactions directes et indirectes entre les semis, les arbres adultes, la végétation herbacée, les insectes herbivores et les pathogènes du sol varient en nature et en intensité le long de gradients climatiques. Pour explorer les interactions entre plantes, j'ai effectué une expérimentation s'appuyant sur la variabilité spatio-temporelle des conditions climatiques dans les Alpes. Les résultats montrent que les effets directs de compétition de la canopée et de la végétation herbacée augmentent avec la température. Cependant, pour les sites les plus chauds, la facilitation indirecte pourrait limiter la compétition directe des herbacées. Pour les interactions avec insectes herbivores,nous avons montré que le long de gradients d'altitude et de latitude, l'herbivorie est minimale là où les stress thermiques et hydriques est fort. Enfin, pour les interactions avec les micro-organismes du sol, nous avons mesuré en chambre de culture la survie de plantules de hêtre dans des sols, stérilisés ou non, collectés le long d'un gradient d'altitude. Les résultats montrent que les effets négatifs des micro-organismes sont plus faibles quand les communautés microbiennes proviennent de sols d'altitudes. Cette thèse suggère que les effets directs négatifs des plantes, des insectes herbivores et des pathogènes du sol sur les semis dominent dans les environnements chauds et productifs et s'atténuent dans des conditions plus froides. Les interactions indirectes semblent varier inversement et pourraient ainsi tamponner l'effet des interactions directes.
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Nyberg, Berglund Anna-Britt. "Postglacial colonization and parallel evolution of metal tolerance in the polyploid Cerastium alpinum /." Uppsala : Dept. of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200565.pdf.
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Müller, Michael [Verfasser], and Thomas [Akademischer Betreuer] Scholten. "Interactions among soil properties and variations in stand structures in the Rolwaling alpine treeline ecotone, Nepal / Michael Müller ; Betreuer: Thomas Scholten." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1198121327/34.
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Müller, Michael Verfasser], and Thomas [Akademischer Betreuer] [Scholten. "Interactions among soil properties and variations in stand structures in the Rolwaling alpine treeline ecotone, Nepal / Michael Müller ; Betreuer: Thomas Scholten." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1198121327/34.
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Rippin, Martin [Verfasser], Burkhard [Gutachter] Becker, Michael [Gutachter] Bonkowski, and Peter [Gutachter] Kroth. "Biological Soil Crust Microalgae and Cyanobacteria - Key Players in Polar and Alpine Ecosystems / Martin Rippin ; Gutachter: Burkhard Becker, Michael Bonkowski, Peter Kroth." Köln : Universitäts- und Stadtbibliothek Köln, 2018. http://d-nb.info/1156712610/34.
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Howes, James E. (James Ernest) Carleton University Dissertation Geography. "An examination of two techniques to determine the origin of soil-sized particles on alpine slopes in the Duke Valley Southwest Yukon." Ottawa, 1991.
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Fuchs, Matthias. "Soil Organic Carbon Inventory and Permafrost Mapping in Tarfala Valley, Northern Sweden : A first estimation of the belowground soil organic carbon storage in a sub-arctic high alpine permafrost environment." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93116.
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Permafrost regions in the Northern Hemisphere store large amounts of organic carbon and are vulnerable to climate change. Due to a sustained warming of the climate, strongest in the northern high latitudes, permafrost thaws and organic carbon could be released in significant amounts which should not be neglected. This study investigates the soil organic carbon (SOC) storage in the Tarfala Valley (600 – 2’100 m a.s.l.), Northern Sweden, and aims to give a first estimation of the total carbon stock in a sub-arctic high alpine permafrost environment. Further the study describes the actual extent of permafrost in the Tarfala Valley. To achieve these aims, two field studies were carried out, one in summer to collect soil samples and one in winter to measure the bottom temperature of snow (BTS). In addition, the soil samples were analysed in the laboratory for bulk density, loss on ignition and elemental analyses. The estimated total SOC in the Tarfala catchment area of 31.2 km2 is 23.0 kt C for 0 – 30 cm and 28.2 kt C for 0 – 100 cm, which is on average 0.9 kg C m-2 for the upper meter of soil in the study area. Even though the soil organic carbon values are relatively low, these results contribute to the on-going soil organic carbon inventories in the circum-arctic. In Tarfala Valley, permafrost can be considered as continuous at an altitude above 1’561 m a.s.l., discontinuous above 1’218 m a.s.l. and sporadic above 875 m a.s.l. based on a logistic regression model with the altitude as single independent variable. This implies that most of the permafrost affected ground is at an altitude where only sparse or no vegetation is present and only low amounts of organic carbon is stored. In brief, Tarfala Valley cannot be considered as a permafrost carbon hotspot, because this sub-arctic alpine environment does not have the potential to release large amounts of carbon as a result of climate warming and permafrost thawing.Permafrost regioner i norra halvklotet lagrar stora mängder av organiskt kol och är känsliga för klimatförändringar. På grund av en pågående klimatuppvärmning, som är starkast i nordliga höga breddgrader, kan permafrosten tina och frisläppa stora mängder av organiskt kol som skulle kunna ha oförutsedda konsekvenser. Denna studie undersöker organiskt kol lagring i marken i Tarfaladalen (600 – 2’100 m.ö.h.), i norra Lappland i Sverige och försöker att beräkna den totala mängden av organiskt kol lagrad i denna subarktiska högalpina miljö. Denna studie beskriver ytterligare den aktuella permafrostutbredningen i Tarfaladalen. Hela examensarbetet är baserat på två fältstudier varav en genomfördes på sommaren för att samla in jordprover och den andra genomfördes på vintern för att mäta bottentemperaturen av snön. Jordprover analyserades i laboratorium för bulk density, loss on ignition och elemental analysis metoderna. Det totalt beräknade organiskt kol i marken i 31.2 km2 stor Tarfaladalen omfattas 23.0 kt C för 0 – 30 cm och 28.2 kt C för 0 – 100 cm, som resulterar i ett medelvärde av 0.9 kg C m-2 för första övre metern av marken. Även om de beräknade mängderna av organiskt kol är ganska små, så bidrar denna studie till de pågående undersökningarna kring organiskt kol i permafrostmarken runt arktis. Permafrostförekomsten i Tarfaladalen betraktas som kontinuerlig över 1’561 m.ö.h. och diskontinuerlig mellan 1’218 och 1’561 m.ö.h. Mellan 875 och 1’218 m.ö.h. betraktas permafrosten som sporadisk. Dessa värden baseras på en logistisk regressionsmodell med höjden som enda variabel men visar att den stora delen av permafrostmarken ligger på hög altitud, vilket innebär att det bara finns lite eller ingen vegetation och inga stora mängder av organiskt kol i permafrostmarken. Slutligen kan man säga att Tarfaladalen inte är någon hotspot för organiskt kol eftersom det där området inte har någon stor potential att släppa fri stora mängder av organiskt kol under ett varmare klimat och tinande permafrosten.
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Kulikov, Maksim [Verfasser], and Udo [Akademischer Betreuer] Schickhoff. "Effects of land use and vegetation changes on soil erosion of alpine grazing lands - Fergana Range, Southern Kyrgyzstan / Maksim Kulikov ; Betreuer: Udo Schickhoff." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1172415544/34.
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Bhople, Parag [Verfasser]. "Effects of climate change on fungal community structure and organic matter turnover in soil profiles along elevation gradients in alpine ecosystems / Parag Bhople." Kassel : Universitätsbibliothek Kassel, 2020. http://d-nb.info/1214841066/34.
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Pech, Pierre. "Contribution à l'étude de la dynamique des versants en montagne alpine : l'exemple de l'Ossola (Alpes centrales-Italie du Nord)." Paris 1, 1988. http://www.theses.fr/1988PA010526.
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Bogna, Ovesca et Anza, vallées situées à l'est du Mont-Rose (4633m), appartiennent au bassin-versant du Toce, affluent du Tessin. Les pentes et les dénivellations sont fortes. Les versants sont taillés dans les roches métamorphiques de la zone interne des Alpes. Les Gneiss résistants qui affleurent à l'ouest et les micaschistes disposés à l'est ont subi l'érosion des grands glaciers quaternaires. Les vestiges des fluctuations tardiglaciaires et postglaciaires -moraines, éboulis- se retrouvent en haute montagne. Actuellement, l'attaque biochimique et la gélifraction agissent sur de larges espaces. La pente formé l'agent principal. Éboulis, solifluxion, avalanches, coulées boueuses, se succèdent sur les mêmes versants. Les processus morphodynamiques sont étagés. Des mesures quantitatives ont effectuées. Les quantités de débris exportés dépendent de la nature du substratum (>10m3 dans les accumulations quaternaires et <1m3 dans les gneiss) et du type de processus (<1m3 pour la gélifraction pure;>1m3 pour les avalanches; > 100m3 pour les coulées boueuses). Une carte des risques naturels potentiels a été réalisée grâce à une étude statistique. À partir d'une carte morphologique on a constitué un tableau matriciel d'après lequel on a tiré des corrélations entre des processus morphodynamiques et des paramètres (lithologie, pente, orientation, couvert végétal, densité de drainage, tranche altitudinale)Bogna, Ovesca and Anza, three valleys to the east of Mont-Rose (4633m) belong to the watershed of Toce, a tributary of the river Tessin. Their slopes and differences in altitude are very important. The valley slopes are cut out in metamorphic rocks of intern alpine zone. The resistant gneisses which breack through in places on western part and the micaschists that are localized on the eastern part, have been eroded by great quaternary glaciers the relict sediments of tardiglacial and postglacial fluctuations-moraines; screes- can be found in high mountain. Biochemic erosion and frost splitting are now acting o wide spaces. Yet the slope is the essential agent of de- gradation. Screes, solifluction, avalanches, mud-flows come one after the other on the same valley slopes. The amount of debris depends on the resistance of the rocks (>10m3 for quaternary accumulations and <1m3 for gneisses) and on the type of processes (<1m3 for frost splitting;>1m3 for avalanches; >100m3 for mud-flow). A map of potential natural hazards has been drawn from a statistical study
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Salomon, Daniel. "Aménagements et techniques de revégétalisation en milieu alpin : Impacts écologiques sur le processus d'humification et d'agrégation des sols anthropiques (pistes de ski), comparaisons avec les sols naturels." Chambéry, 2003. http://www.theses.fr/2003CHAMS026.
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Les objectifs de l'étude consistaient à mesurer l'impact des travaux d'aménagements et de revégétalisation sur les propriétés physico-chimiques et biologiques des sols d'altitude afin d'évaluer le degré de restauration et ou de réhabilitation des écosystèmes sols. Nous avons mesuré, sur 22 sites d'études répartis sur deux stations (La Plagne et Val-Thorens), divers paramètres physiques et chimiques du sol (pH, carbone organique, azote, porosité, humidité, granulométrie, agrégation. . . ) et nous avons quantifié la faune présente (arthropodes, vers de terre. . . ). Nous montrons des différences significatives entre les réserves organiques, le degré d'humidité, la granulométrie (dominance des sables sur les pistes), l'agrégation entre les sols naturels et reconstitués. . . Mais la stabilité structurale dépend fortement de la technique de revégétalisation. La faune du sol présente dans ces substrats de pistes est composée de groupes pionniers et ubiquistes. Nous avons montré une modification importante des régimes alimentaires (géophagie). De plus, les communautés animales évoluent au cours du temps. Et cette évolution va dépendre en partie de la technique de révégétalisation qui va la positionner sur une trajectoire qui rapprochera la communauté "anthropisée" de la communauté naturelle, ou bien la conduira vers une nouvelle structure communautaire. En fonction de nos résultats, nous proposons aux aménageurs des solutions en vue d'améliorations possibles de leurs travaux de revégétalisationThe aims of the study consisted in measuring the impact of the revegetalisation and alteration work on the physicochemical and biological properties of the grounds in order to evaluate the degree of restoration and or rehabilitation of the ecosystem grounds. We measured, on 22 sites of studies distributed on two stations (Plagne and Valley-Thoren), various physicical and chemical parameters of the ground (pH, organic carbon, nitrogenizes, porosity, moisture, granulometry, aggragation. . . ) and we quantified fauna (arthropods, ground worms,. . . ). We show significant differences between the organic reserves, the percentage of moisture, granulometry (predominance of snads on the tracks), aggregation between the original and reconstituted grounds. . . But structural stability strongly depends on the technique of revegetalisation. The fauna of the ground present in these substrates is made up of pioneers groups and ubiquists. We showed an important modification of the diets (géophagie). Moreover, the animal communities evolve in the time. And this evolution will depend partly on the technique of revegetalisation which will position it on a trajectory which will bring closer the "anthropized" community the natural community, or will lead it towards a new Community structure. According to our results, we propose to the developers solutions for possible improvements of their work of revegetalisation
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Tuo, Ye [Verfasser], Markus [Akademischer Betreuer] Disse, Markus [Gutachter] Disse, Gabriele [Gutachter] Chiogna, and Niels [Gutachter] Schütze. "Application of the Soil Water Assessment Tool (SWAT) in alpine catchments: pitfalls and solutions / Ye Tuo ; Gutachter: Markus Disse, Gabriele Chiogna, Niels Schütze ; Betreuer: Markus Disse." München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/116227509X/34.
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Pascual, Didac. "Soil organic carbon storage, distribution and characteristics in two contrasting permafrostaffected environments : Evaluating the role of alpine and lowland tundra areas in the permafrost carbon feedback." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-159797.
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An important portion of the large northern permafrost soil organic carbon (SOC) pool might be released into the atmosphere as greenhouse gases following permafrost thawing and subsequent SOC decomposition under future warming conditions, resulting in a warming amplification known as the permafrost carbon feedback. Improved knowledge about the amount, composition and distribution of the permafrost SOC pool is essential when assessing the potential magnitude and timing of the permafrost carbon feedback. This study investigates and compares the SOC storage, composition and distribution in two contrasting permafrost environments: a lowland tundra area in NE Siberia (Tiksi study site), and an alpine area in the Russian Altai Mountains (Aktru Valley study site). Soil pedons were sampled down to 1 m depth and analyzed for key soil properties, i.e., DBD, water content, coarse fraction content, %OC, %IC, C/N ratios and δ¹⁵N values. These soil properties are upscaled by vertical subdivisions based on land cover classes. The role of geomorphology in the accumulation and distribution of SOC in the alpine study site is tested by using a landform and a combined land cover-land form upscaling approach. The estimated mean SOC storage in the upper meter of soils in the alpine site is 3.5 ± 0.8 kg C m¯² compared to 21.4 ± 3.2 kg C m¯² in the lowland tundra site (95% confidence intervals). The inclusion of geomorphology in the upscaling in some cases allows identification of SOC hotspots and areas with very low SOC storage within former land cover classes, therefore improving the landscape SOC storage distribution in the area. The much lower SOC stocks in the alpine site of Aktru Valley can be largely explained by the presence of extensive unvegetated areas in high altitudes (60%), the occurrence active layers deeper than the active soil formation, the enhanced SOM decomposition due to coarse grained, well-drained non-frozen soils, and the negligible occurrence of peatlands and buried organics. Instead, the lowland tundra site in NE Siberia presents important amounts of relatively undecomposed SOM in the permafrost layer. Thus, under future climate warming, alpine permafrost environments such as Aktru Valley may become a net C sink due to an upward shift of vegetation zones and an increase in plant productivity and soil development. Contrarily, lowland tundra areas such as Tiksi may become important C sources since the small increase in C uptake by photosynthetic plants will be outweighed by the thawing and subsequent decomposition of the much larger permafrost SOC pool.
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Rist, Armin. "Hydrothermal processes within the active layer above alpine permafrost in steep scree slopes and their influence on slope stability /." Zürich : Geographisches Institut der Universität Zürich, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016771587&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Grossi, Jean-Luc. "Caractérisation écologique et statut dynamique des écosystèmes post-culturaux dans différentes situations bioclimatiques alpines : intéret des descripteurs liés à l'humus." Grenoble 1, 1995. http://www.theses.fr/1995GRE10091.
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Cette recherche contribue a une meilleure comprehension des interactions sol/plante dans le fonctionnement et l'evolution des ecosystemes post-culturaux dans differentes regions bioclimatiques des alpes francaises. Elle aborde en fait un sujet d'ecologie fonctionnelle qui touche aux preoccuppations actuelles des recherches sur l'evolution des ecosystemes et des paysages dans le contexte des changements d'utilisation des milieux naturels par l'homme (deprise agricole). Les descripteurs lies a l'humus sont utilises ici pour evaluer les ecosystemes en cours d'evolution, en particulier les phases a boisements feuillus. C'est pourquoi l'etude de la faune du sol a ete couplee a l'etude structurale de l'humus en faisant appel a l'analyse d'images assistee par ordinateur. Une confrontation de cette methode avec celles, plus globales et plus classiques relatives a la phytoecologie et l'hydropedologie montre tout l'interet de cette approche dans les situations d'evolution rapide du couvert vegetal (quelques decennies). L'etude des boisements spontanes dans differentes situations bioclimatiques permet une meilleure evaluation du statut dynamique de ces formations, longtemps negligees par ecologues et forestiers. Ces connaissances sont enfin utilisees pour aider les gestionnaires des espaces ruraux a mieux orienter leurs interventions
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Chiffard, Jules. "Oiseaux chanteurs des milieux ouverts de montagne et changements globaux." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEP038.
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Du fait de la croissance démographique et économique de la population humaine, nos sociétés sont de plus en plus dépendantes de la nature, et plus précisément de certains processus biologiques regroupés sous le terme services écosystémiques. Comprendre les mécanismes de réponse des systèmes biologiques face aux changements globaux que nos activités induisent à plusieurs échelles est donc un enjeu scientifique et de société. Cette thèse a été pensée et réalisée en interaction avec plusieurs équipes de recherche et gestionnaires d’espaces naturels dans le cadre du développement d’un suivi temporel des oiseaux de montagne comme indicateurs des conséquences des changements globaux sur la biodiversité. Les massifs montagneux de France sont en effet exposés aux changements de climat et à l’évolution de l’élevage des grands herbivores, une activité exposée aux fluctuations des prix des matières premières et des aides publiques. Les forts gradients bioclimatiques « en facettes » (selon l’exposition) qui caractérisent des massifs montagneux font de ces espaces des modèles d’étude particulièrement intéressants pour étudier les effets des changements globaux sur la biodiversité, mais aussi fortement contingents. L’objet général de ma thèse est d’identifier et de quantifier le rôle respectif de la température, de la structure de la végétation, et des activités d’élevage, sur cette communauté d’oiseaux, afin de mieux comprendre quelles pourraient être les conséquences de changements majeurs de climat et d’usage des terres. Les gradients altitudinaux ont été historiquement étudiés de façon isolée et dans de grandes diversités d’habitats. Suivant les objectifs généraux de la thèse nous avons choisi d’adopter l’approche inverse dans le premier chapitre, en multipliant les sites d’études dans un habitat standardisé (1100 points d’écoute réalisés dans les Alpes et les Pyrénées). Nos résultats montrent que la ressource, la température et la structure de l’habitat influent fortement sur la communauté. De plus 5 des 8 espèces étudiées semblent favorisées par le pâturage. Dans le second chapitre, j’ai testé l’effet de la forte saisonnalité qui caractérise le climat des massifs montagneux tempérés, en testant son effet sur la survie individuelle dans une population de Chocards à bec jaune Pyrrhocorax graculus. Je me suis appuyé pour cela sur un suivi individuel (CMR) d’un millier d’individus mené pendant 30 ans par Anne Delestrade. Les Chocards présentent une survie forte et un patron saisonnier, en interaction avec le sexe des individus, avec une survie plus basse pour les femelles après les hivers et printemps chauds. J’ai ensuite présumé que les passereaux insectivores savent profiter des troupeaux en consommant des insectes coprophages. J’ai mesuré les ratios isotopiques stables de l’azote présents dans les fèces des oiseaux les plus communs pour estimer le niveau trophique de leurs proies, et ainsi tester cette hypothèse et quantifier le mécanisme. On observe dans les deux massifs un décalage très marqué vers le prélèvement d’insectes non-herbivores quand l’intensité de pâturage augmente. Le dernier chapitre évalue le potentiel d’échantillonnages itératifs basés sur des modèles de répartition d’espèces pour augmenter la probabilité de contacter une espèce rare dans de nouvelles localités. Cette étude comprend des simulations et un test de terrain dans les Pyrénées sur la Niverolle alpine Montifringilla nivalis et le Monticole de roche Monticolla saxatilis. Les résultats montrent le fort potentiel de la méthode en pratique, et ses limites, avec une augmentation de la spécificité au détriment d’une augmentation des omissions. En discussion générale, je propose des perspectives de recherche visant à généraliser le lien fort entre régime alimentaire des oiseaux de montagne et troupeaux de mammifères herbivores, et à mieux comprendre la phénologie des populations des pelouses d’altitude en fonction de l’enneigementGrowth of human populations and economy causes human societies to be more and more dependent on ecosystem services. Understand the mechanisms underlying the response of biological systems to global changes is thus a scientific and social issue. This research was thank and realized when developing a long term monitoring scheme for mountain birds with different research teams and conservation stakeholders. In this long term monitoring, birds are used as indicators of the effects of global changes on biodiversity. Mountain massifs of France are exposed to climate change, and land use evolution, as livestock grazing is dependent on raw material prices and public support. Mountains are interesting, but contingent, ecological contexts to study the effects of global changes on biodiversity, due to the sharp bioclimatic gradients and facet landscapes. My main objective was to characterize and quantify the respective effects of temperature, vegetation structure, and livestock grazing activities on this bird community, to better predict the consequences of major climate and land use changes. Elevation gradient have been mostly studied in isolated sites and large elevation gradients. Following our main objective, in the first chapter, we chose the opposite approach, by multiplying study sites in a standardized habitat (open grasslands, 1100 point counts in Alps and Pyrenees). Our results show that primary productivity, temperature and habitat structure all influence the bird community. Also 5 out of the 8 most common species seemed to be favorited by livestock grazing activities. In the second chapter, I tested the effect of the strong seasonality typical from temperate mountains’ climate, by testing it’s effect on the survival of individuals in a population of alpine Choughs Pyrrhocorax graculus. I relied on the CMR survey of more than 1000 individuals carried out by Anne Delestrade during 30 years. Choughs show the highest survival known in corvids, with a seasonal pattern, in interaction with individuals’ states like sex group. Adult females also showed lower spring survival after warm winters. In third chapter I speculated on the ability of insectivorous passerines to get benefit from the presence of large domestic herbivorous mammals, by eating coprophagous insects. I measured the stable nitrogen isotopic ratios in the feces of most common birds to provide an estimation of the trophic level of birds’ preys, and thus test my hypothesis and eventually quantify the mechanism. We observed, in both mountain massif, a shift from herbivorous from higher trophic level insects catched by birds, from locations with low grazing intensity to those with high grazing intensity. The last chapter present an evaluation of the potential of adaptive niche based sampling to increase the ability to find rare species in new localities. This study includes simulations and field test in the Pyrenees mountains on two alpine bird species, Snowfinch Montifringilla nivalis and rock Thrush Monticolla saxatilis. Results show the strong potential of the method in the field, and its limit, with an increase in specificity at the cost of omissions that also increase. As a general discussion, I develop research perspective to generalize the strong link found between birds’ diet and large mammalian herbivores, and to better understand the phenology of populations facing unpredictable snow cover during breeding period
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Rezzoug, Samya. "Utilisation d'isotopes naturels dans les familles de ²³⁸U et de ²³²Th pour une étude environnementale : impact des retombées atmosphériques du ¹³⁷37Cs dans des sols forestiers et des sédiments lacustres : application à l'étude d'une zone alpine (Boréon, Mercantour, S. E. France)." Nice, 2005. http://www.theses.fr/2005NICE4060.
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Des échantillons de sédiments lacustres et de sols forestiers ont été prélevés dans le massif du Mercantour. La distribution verticale de l’uranium et du thorium, dans les sols a montré que des lessivages ont eu lieu à divers niveaux ainsi que des réactions de précipitation à partir des eaux de ruissellement de surface et/ou de sub-surface. L’application des modèles de Latham et Schwarcz (1987), et de Nordeman-Moreira (1980), ont confirmé le lessivage du thorium en sub-surface des sols. Une évaluation des retombées en 1986 du 137Cs, a pu être réalisée par comparaison avec le comportement du 210Pb d’origine atmosphérique. Les fortes activités en 137Cs présentes dans les niveaux supérieurs des carottes de sol et de sédiment témoignent, 17 ans après la catastrophe de la centrale nucléaire de Tchernobyl en avril 1986, d’un long temps de résidence dans les bassins versants. Dans les carottes prélevées dans le lac, une discontinuité majeure est apparue dans tous les profils de la matière organique (M. O. ), avec de plus fortes concentrations dans la partie supérieure. La coupure se retrouve pratiquement dans tous les profils des radionucléides étudiés. Elle est liée à un curage du fond du lac effectué en 1991-92. La partie inférieure de certaines carottes de sédiments est vraisemblablement constituée du sol sous-jacent, puisque les concentrations en M. O. Des niveaux profonds sont proches de celles des sols, et que les activités en 137Cs et 210Pb sont négligeables. Le 137Cs présent dans les niveaux profonds peut provenir soit des essais nucléaires (1960-63), soit d’infiltrations à partir des niveaux supérieurs, essentiellement contaminés par le 137Cs de TchernobylLake sediment samples and forest soils were collected in the Mercantour massif. The uranium and thorium, vertical distributions in soils show that leaching occurred at several levels as well as precipitations from surface and/or sub-surface runoff waters. The application of Latham and Schwarcz’s equation (1987) and Moreira-Nordeman’s model (1980) confirmed thorium leaching in sub-surface soils. The 137Cs fallout in 1986, after the Chernobyl power plant accident, was evaluated by comparison with the unsupported 210Pb behaviour. The 137 Cs high activities in the soil upper layers 17 years after the Chernobyl accident as well as the activities in upper latke sediments suggest that the residence time of 137Cs in the drainage basins is long. In all the lake core, organic matter (O. M. ) profiles display a concentration break with the higher concentrations in the upper part. This break is also observed practically in the all studied radionuclides profiles, with higher or lower activities according to the radionuclides and sites. Lake emptying and scraping realized in 1991-92 are responsible for this pattern. The lower part of some sediment cores is probably constitute by underlying soil, because the O. M. Concentrations in the deep layers are similar as those of soils, and the 137Cs and 210Pb activities are negligible. During the lake emptying the correspondent sedimentary level was probably removed. The 137Cs present in the deeper layers can result from either nuclear tests (1960-63), or infiltrations from the upper layers, essentially contaminated by the Chernobyl 137Cs
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Pinto, Victor Hugo. "Linking tectonic evolution with fluid history in hyperextended rifted margins : examples from the fossil Alpine and Pyrenean rift systems, and the present-day Iberia rifted margin." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAH018/document.
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Cette thèse est centrée sur la caractérisation des traceurs des fluides qui interagissent avec les roches du socle et les roches sédimentaires dans les systèmes riftés hyper-amincis exposés dans la Téthys alpine, les Pyrénées et Ibérie-Terre Neuve. L’étude de ces fluides est basée sur les observations géologiques, les analyses géochimiques et les données géophysiques. Deux types de fluides ont été identifiés : les fluides associés à la croûte continentale, avec une signature caractérisée par Si et Ca, ainsi que les fluides liés au manteau en exhumation, avec une signature caractérisée par Si, Mg, Fe, Mn, Ca, Ni, Cr et V. La percolation des fluides est fortement liée à la formation des failles de détachement et à l’évolution des systèmes hyper-amincis. Le flux de fluides dans ces systèmes a des implications importantes pour les changements rhéologiques, pour la nature des sédiments et pour les modifications chimiques des réservoirs de la TerreThis thesis focus in the identification of geochemical tracers and effects of fluid that interact with basement and sedimentary rocks in hyperextended systems. The investigation of such fluids is based on geological observation, geochemical analyses and geophysical data from fossil hyperextended rift systems exposed in the Alps and in the West Pyrenees, and the present-day distal margins of Iberia and Newfoundland. Two types of fluids were identified during this study. The first type, referred to as continental crust-related fluids, has a signature of Si and Ca. The second type, referred to as mantle-related fluids, has a signature of Si, Mg, Fe, Mn, Ca, Ni, Cr and V. The fluid percolation is strongly related to the formation of extensional detachment faults and the evolution of hyperextended systems. Fluid flow in these systems has major implications for the nature of sediments, rheological changes and chemical modifications of the Earth’s reservoirs throughout its evolution
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Verger, Jean-Pierre. "Végétation et pédogenèse sur roches vertes et gneiss acide dans une séquence altitudinale montagnard-alpin en Val d'Aoste (Italie) : essai de synthèse écologique." Grenoble 1, 1987. http://www.theses.fr/1987GRE10081.
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Sue, Christian. "Dynamique actuelle et récente des Alpes occidentales internes : Approche structurale et sismologique." Phd thesis, Grenoble 1, 1998. http://tel.archives-ouvertes.fr/tel-00463852.
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La tectonique récente et actuelle de l'arc des Alpes occidentales internes est étudiée ici d'un point de vue structural et sismologique. L'approche pluridisciplinaire de ce sujet a permis de caractériser un régime tectonique tardi-alpin extensif à grande échelle dans les zones internes. L'analyse structurale et morphotectonique d'une zone cible, au sud-est du massif du Pelvoux, montre qu'une fracturation tardi-alpine extensive s'y exprime suivant un réseau de failles longitudinales et transverses à l'arc alpin. Cette déformation cassante est postérieure à la mise en place des nappes de charriage, à leurs plissements et aux schistosités associées, la dernière se développant au cours du Miocène. Elle se poursuit au Plio-Quaternaire, comme le montre un faisceau d'indices néotectoniques. Un jeu décrochant est postérieur au jeu normal ; il s'exprime par des mouvements dextres suivant les failles longitudinales et sénestres suivant les failles transverses. Le calcul des champs de contraintes associés (inversion des données microtectoniques) montre que les jeux normaux et décrochants correspondent à une seule « phase » tectonique globalement transtensive au cours de laquelle il y a permutation des axes de contraintes principaux. La zone cible fait partie de l'arc sismique briançonnais. Le calcul des mécanismes au foyer dans ce secteur établit que l'extension cassante tardi-alpine se poursuit actuellement. L'amélioration des localisations par l'utilisation de modèles de vitesses élaborés (1D/3D) a permis de montrer que plusieurs failles reconnues par l'analyse structurale sont sismiques. L'étude de la fracturation et les coupes sismotectoniques en arrière du front pennique crustal montrent que les failles normales se branchent sur cette discontinuité majeure de l'arc alpin, et suggère sa réactivation en détachement extensif. Les résultats d'une campagne de mesures GPS de 1996 dans la zone cible, comparés à des données IGN de 1972, sont compatibles avec les analyses sismotectonique et structurale. Ils mettent en relief une déformation plutôt décrochante, avec des vitesses de l'ordre de 3 à 4 mm/an. La déformation asismique dépasse 90% de la déformation totale déduite de ces mesures, durant le laps de temps considéré. L'élargissement de l'approche sismotectonique à l'ensemble des zones internes de l'arc alpin occidental montre que l'extension se développe au nord jusqu'au massif de l'Aar, et à l'est dans l'arc sismique piémontais. L'activité de ce dernier se localise à la bordure occidentale du corps d'Ivrée, laquelle fonctionne actuellement en faille normale. Le calcul du champ de contraintes actuel (inversion des solutions focales) permet de caractériser une extension radiale à l'arc alpin occidental dans une grande partie de ses zones internes. Elle entraîne la réactivation en extension des structures crustales majeures (front pennique crustal et bordure ouest du corps d'Ivrée). De part et d'autre de la zone en extension, le champ de contraintes est compressif (à l'est sous la plaine du Pô ; à l'ouest au front des massifs cristallins externes). L'extension affecte donc une zone de 400 km de long et de 50 km de large au coeur d'une chaîne en convergence. Une compétition entre des forces de volume dans la racine lithosphérique alpine et les forces aux limites de la chaîne (translation et rotation du poinçon apulo-adriatique) pourrait être à l'origine du contraste de régimes tectoniques mis en évidence dans l'arc alpin occidental. Nous proposons deux modèles dynamiques dans lesquels l'extension s'explique par le détachement ou le retrait d'un panneau lithosphérique plongeant sous la racine alpine.
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Brau-Nogué, Catherine. "Dynamique des pelouses d'alpages laitiers des Alpes du Nord externes." Université Joseph Fourier (Grenoble ; 1971-2015), 1996. http://www.theses.fr/1996GRE10004.
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Les alpages laitiers des alpes du nord externes (france) representent un type de systeme ecologique original refletant les effets des pratiques d'eleveurs (fertilisation, paturage) combines aux contraintes du milieu montagnard (etage subalpin). Face aux mutations recentes des modes d'exploitation des alpages, des recherches ont ete engagees pour comprendre et prevoir l'impact des pratiques pastorales sur la dynamique de ces pelouses d'altitude. Nous proposons un modele d'evolution de la composition botanique qui integre l'effet des facteurs anthropiques et celui des facteurs edaphiques. Ce modele s'appuie sur une analyse factorielle des correspondances portant sur un echantillonnage de six cent releves floristiques couvrant l'ensemble de la zone d'etude. La reconstitution des trajectoires dynamiques se fait principalement par une approche synchronique, completee par des observations diachroniques qui ont permis de preciser les vitesses d'evolution de la vegetation. L'essentiel des travaux porte sur des situations de deprise: la dynamique de la vegetation y reflete une degradation de la fertilite des sols consecutive a l'abandon ou a l'allegement de la fertilisation. Cette evolution est generalement lente: deux a cinq decennies sont necessaires pour que l'on enregistre des changements notables dans la composition botanique. Les resultats mettent egalement en evidence l'influence des parametres edaphiques sur les limites et le deroulement de ces successions. Les modalites d'evolution de la vegetation et la hierarchie des facteurs sont precisees dans des trajectoires-types qui permettent d'adapter localement la demarche de diagnostic ecologique. Differents indicateurs, relatifs aux processus physiologiques ou demographiques d'evolution de la vegetation, sont testes afin de preciser ou d'anticiper le diagnostic floristique. Les indices de diversite specifique ou factorielle restent d'un usage delicat en raison de leur sensibilite a l'egard des methodes d'echantillonnage et d'observation. Les indices de nutrition minerale font rapidement apparaitre les modifications d'equilibres trophiques qui suivent l'arret ou la reprise de la fertilisation
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Cheng, Yi Wen, and 程意雯. "Formation of lepidocrocite and goethite in alpine forest soils of Taiwan." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/66605446619872619228.
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碩士國立臺灣大學
農業化學研究所
83
The two alpine forest soil pedons are from Tung-Bao-Chin-Han and Shih-Yun-Ya-Kuo. These soil profiles consisted seven horizons with placic horizons located at 28-28.5 centimeter and 68-72centimeter.The soils were extracted by dithionite-citrate- bicarbonate solutions for free sesquioxides, by ammonium-oxalate solution and sodium-pyrophosphate for soil irons. High free iron oxide contents were found in placic horizons. For simulating the formation of lepidocrocite and goethite in the placic horizon, incorporation of Al and that organic acids favored to form goethite during synthesis of lepidocrocite at various ferrous concentration, pH, and temperature. The precipitates were investigated by X-ray diffration, transmission electron microscopy, and chemical analysis. Lepidocrocite formed under ferrous at pH 5.0-6.4 and pH at 6.5 formed as maghemite or magnetite. Temperature at 40 C first 6-hr reaction period precipitated as lepidocrocite and maghemite produced at 8-hr. Lepidocrocite formed at Al/Fe molar ratio 0-0.005; the mixture of lepidocrocite and goethite from solution with Al/Fe ratios = 0.01-0.04; incorporation of large amounts of Al into ferrous solution, Al/Fe of 0.05-0.25 formed goethite. Acetic acid/Fe and oxalic acid/Fe molar ratios of 0.005-0.1 and citric acid/Fe molar ratios of 0.001-0.05 produced lepidocrocite precipitates.
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"Sexual reproductive processes of plants in an alpine tundra environment." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-04-2063.
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Sexual reproduction is an important mechanism shaping plant community composition that will likely be affected by unprecedented rates of climate change in Canada’s North. To anticipate potential changes in plant communities, I aim to understand how changing environmental conditions affect the processes of seed production and seedling emergence, and determine the overall impacts on the reproductive potential of alpine tundra vegetation in Yukon, Canada. I tested the effect of soil warming and nitrogen addition treatments on the timing and success of sexual reproduction of the six tundra species; Dryas octopetala M. Vahl, Salix arctica Pall, Salix reticulata L., Lupinus arcticus L., Carex microchaeta Holm, and Hierochloë alpina (Sw.) R. & S. A summer snow event occurred on 2 July 2012, and I considered the impacts of such an event on the reproductive timing and success of the study species. I also examined the influence of seed availability and soil conditions on initial seedling emergence of three tundra species and three boreal species. I applied seed to natural disturbance sites with bare substrate exposed, and to plots with altered soil temperature and nitrogen availability. Results indicated that reproductive phenology, seed production, and seed viability of tundra species were not affected by increases in soil temperature and/or nitrogen availability but were impacted by the snowfall event. In addition, changes in soil temperature and nitrogen did not affect seedling emergence. Seedling emergence of both boreal and tundra species increased on bare substrates, indicating that surface disturbance creates opportunities for seedling establishment. Overall, my study shows that factors affecting seed production and local disturbance will have greater impact on the success of sexual reproduction in tundra plant communities than changes in soil temperature or nutrients caused by climate change.
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Chen, Liang-Guu, and 陳亮谷. "Study of Fertilization on Nutrient Losses in Alpine Soils from Central Taiwan." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/33602158259609191754.
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碩士國立中興大學
土壤學系
84
Abstract Fruits and vegetables were planted years at the area of Li-shang and Wu-ling in central Taiwan. The hidden danger of soil loss, fertilizer loss, water pollution and the connection of fertilizer loss and water pollution with soil fertilizer potential of nutrient retained became critical after great amounts of fertilizers were applied. The first objective of this study is to investigate the soil fertilizer potential index of nutrient retained of the soils from vegetable field in mountain and orchard in slopeland. Second, this study provide strategies for amelioration by assessing the potential of nutrient retained of soils applied with fertilizers. The potential index of available nutrient of four chosen soils - vegetable field soil in mountain (Wu-ling farm), orchard field soil in slopeland (Li-shang), vegetable field soil in lowland (Erh-ling series, Chang-hua Shi-hu) and forest soil (Li- shang) are 271, 45, 87 and 30%. In the first experiment, the soils mentioned above ( including gravel) were soaked in the distilled water added with 176 mg N L-1 of urea or 120 mg N L-1 of NH4NO3 by the ratio of 1:1 for 12 hr then leached out as the initiative leaching. Same steps were held in the 3rd, 10th, 24th, 45th and 73rd day as the 2nd, 3rd, 4th, 5th and 6th leaching. The results showed that vegetable field soil in mountain contained great amount of soluble N. The retained N and extracted N of cultivated soil reached to an equilibrium after four or five times of leaching within the application range of 600~700 mg N L-1 and the retained N in soil of forest is higher than that of vegetable field in mountain at the early applicationas well as extracted N from forest soil exceeded that from vegetable field soil in mountain after excess applications. The experiment was also treated under 3 different levels of temperature. The result showed that the percentage of nutrient loss decreased as the temperatures dropped. In the 3rd experiment, the 2 mm sieved soil from vegetable field in mountain was ready for the column leaching. Soils added with different fertilizers - urea (24 mg N L-1), peat, Bagasse manure and poultry manure were soaked in distilled water by water: soil = 2:1 for 12 hr﹐then leached out as the initiative leaching. Same steps were held in the 7th, 21st, 42nd, 70th and 105th day as the 2nd, 3rd, 4th, 5th and 6th leaching. Although urea mobilizes quickly yet no change of microorganism population was found during six times of incubation in 105 days. Though peat contains very low soluble salts, stable decomposing rate and the ability to absorb NO3- made it a better fertilizer even when it was leached. Besides, the populations of bacteria and actinomycetes was significant different after leaching and incubation. Soluble N, K, Ca, Mg and S in Bagasse manure were high. Much amount of nutrient was left because high levels of nutrient were contained in poultry manure including Cu and Zn. After times of application would lead to the accumulation of Cu and Zn. The results of these experiments came to the conclusion that vegetable field soil in mountain exhibited a high potential index of nutrient and a great amount of soluble N. But weak fertilizer holding capacity. Fertilizer loss and water pollution will be induced easily when if precipitate or irrigate. Applying materials of organic substances, such as peat, would create several advantaged , like decrease the amount of application of soluble N, minimize the cost, decrease the loss of N , enrich the fertility of soil and most important of all it will, keep the agriculture development sustainable.
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Cho, Shine-Tsern, and 卓昕岑. "Studies in Microbial population of Alpine Tatachia and Low Altitude Fu-Shan Forest soils." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/57503203440937014236.
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碩士國立臺灣大學
農業化學研究所
91
To investigate the effect of attitude on microbial ecology of forest soils and the role of microbes on the organic matter decomposition and nutritional flow, Tatachia and Fu-Shan forests were chosen. Environment conditions of atmospheric and soil temperatures, light intensity, soil properties of moisture content, pH, total organic carbon, total nitrogen and C/N ratio and populations of total count, actinomycetes, fungi, cellulolytic microbes, phosphate-solubilizing microbes and nitrogen-fixing microbes were measured during the past year. In addition, microbial biomass carbon, microbial biomass nitrogen and DNA content were also studied. In the case of Tatachia forest, Spruce soil had moisture content 29.31-75.71 %, pH 3.93-5.34, total organic carbon 5.83-24.51 %, total nitrogen 0.43-2.71 %, C/N ratio 5.21-20.79 and ash content 31.11-84.58 %; Hemlock soil had moisture content 35.29-78.01 %, pH 3.34-4.48, total organic carbon 2.25-38.69 %, total nitrogen 0.23-2.43 %, C/N ratio 8.76-25.32 and ash content 29.07-88.45 %; grassland soil had moisture content 29.31-63.37 %, pH 3.62-5.13, total organic carbon 1.11-38.78 %, total nitrogen 0.12-1.48 %, C/N ratio 7.28-30.55 and ash content 72.96-93.76 %. In microbial ecology, each gram of dry spruce soil contained total microbes 1.04×105-1.64×l07 CFU, actinomycetes 8.02×102-1.42×105 CFU, fungi 1.22×104-1.65×106 CFU, cellulolytic microbes 6.55×104-3.61×106 CFU, phosphate-solubilizing microbes 1.72×104-5.58×105 CFU, nitrogen-fixing microbes 1.23×105-4.38×106 CFU, microbial biomass carbon 438.22-1345.23 μg-C, microbial biomass nitrogen 20.68-229.25 μg-N and DNA 11.12-44.65 μg. Each gram of dry hemlock soil contained total microbes 5.22×104-1.34×l07 CFU, actinomycetes 63×103-1.49×105 CFU, fungi 5.83×104-7.49×105 CFU, cellulolytic microbes 1.05×105-3.71×106 CFU, phosphate-solubilizing microbes 1.29×104-8.89×105 CFU, nitrogen-fixing microbes 1.05×104-6.93×105 CFU, microbial biomass carbon 132.27-1065.25 μg-C, microbial biomass nitrogen 11.46-166.45 μg-N and DNA 11.29-45.98 μg. Each gram of dry grassland soil contained total microbes 4.54×104-1.26×l07 CFU, actinomycetes 9.91×102-8.38×105 CFU, fungi 5.98×103-5.52×105 CFU, cellulolytic microbes 1.09×104-3.41×106 CFU, phosphate-solubilizing microbes 7.28×103-5.49×105 CFU, nitrogen-fixing microbes 3.91×104-6.28×105 CFU, microbial biomass carbon 126.11-1145.65 μg-C, microbial biomass nitrogen 21.15-178.91 μg-N and DNA 8.32-38.49 μg . In the case of Fu-Shan forest, valley soil had moisture content 41.01-72.35 %, pH 4.23-4.73, total organic carbon 5.03-21.46 %, total nitrogen 0.27-0.92 %, C/N ratio 12.11-33.72 and ash content 65.48-87.63 %；middle slope soil had moisture content 44.29-68.91 %, pH 3.76-4.32, total organic carbon 3.15-32.14 %, total nitrogen 0.23-0.91 %, C/N ratio 12.47-28.54 and ash content 51.04-87.44 %； ridge soil had moisture content 36.91-61.11 %, pH 4.06-4.63, total organic carbon 2.41-41.18 %, total nitrogen 0.18-0.88 %, C/N ratio 6.09-48.02 and ash content 45.52-86.45 %. In the microbial populations, each gram of valley soil contained total microbes 1.18×106-1.26×l07 CFU, ctinomycetes 1.02×103-8.38×105 CFU, fungi 1.49×104-5.52×105 CFU, cellulolytic microbes 5.09×104-3.41×106 CFU, phosphate-solubilizing microbes 1.03×105-5.49×105 CFU, nitrogen-fixing microbes 9.65×104-6.28×105 CFU, microbial biomass carbon 48.89-983.65 μg-C, microbial biomass nitrogen 20.31-266.51 μg-N and DNA 2.87-26.81μg. Each gram of middle slope soil contained total microbes 2.01×106-1.26×l07 CFU, actinomycetes 4.32×102-8.38×105 CFU, fungi 2.11×104-5.52×105 CFU, cellulolytic microbes 7.08×104-3.41×106 CFU, phosphate-solubilizing microbes 1.21×105-5.49×105 CFU, nitrogen-fixing microbes 1.21×105-6.28×105 CFU, microbial biomass carbon 124.61-910.21 μg-C, microbial biomass nitrogen 18.21-196.33 μg-N and DNA 3.21-31.46 μg. Each gram of ridge soil contained total microbes 6.18×105-9.88×l07 CFU, actinomycetes 1.03×102-6.98×104 CFU, fungi 6.59×103-6.97×106 CFU, cellulolytic microbes 2.07×104-8.31×106 CFU, phosphate-solubilizing microbes 1.04×104-2.26×106 CFU, nitrogen-fixing microbes 9.65×104-9.79×106 CFU, microbial biomass carbon 257.31-1013.56 μg-C, microbial biomass nitrogen 33.11-257.44 μg-N and DNA 3.45-38.49 μg. In the soil profiles of Tatachia grassland and Fu-Shan ridge soil, the pH was low at the topsoil, while total organic carbon and total nitrogen were reversed and had high values at the topsoil. In the case of microbial populations, the number decreased with increasing of soil depth. The populations decreased as follows: 88.23-91.65 %, 72.67-92.38 %, 69.36-96.56 %, 56.21-89.41 %, 75.63-83.84 % and 59.17-89.93 % in total microbes, actinomycetes, fungi, cellulolytic microbes, phosphate-solubilizing microbes, and nitrogen-fixing microbes, respectively. In the case of Fu-Shan ridge profile, the populations at the bottom horizon decreased as follows: 88.23-91.65 %, 72.67-92.38 %, 69.36-96.56 %, 56.21-89.41 %, 75.63-83.84 % and 59.17-89.93 % as those of topsoil in total microbes, actinomycetes, fungi, cellulolytic microbes, phosphate-solubilizing microbes and nitrogen-fixing microbes, respectively. In the forest soil DNA extraction and purification, we modified Krsek’s methods by extending Lysis time, adding AlK(SO4)2, PVPP as pre-washed treatment and PVP gel exciding if the final product was still dirty. In the DGGE profile of Fu-Shan forest soil, the three sampling sites had similar soil microbial populations. The organic layer had the larger microbial amounts than topsoil, and subsoil had less microbial amounts. The valley soil had the fewer microbial diversity and less microbial amounts compared to other two sampling sites.
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Johnston, Stuart William. "Function and sustainability of Australian alpine ecosystems : studies in the tall alpine herbfield community, Kosciuszko National Park." Phd thesis, 2007. http://hdl.handle.net/1885/147723.
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Shahnavaz, Bahar. "Communauté bactérienne de sols alpins et filtres environnementaux." Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-00515414.
Full textAbstract:
Les bactéries jouent un rôle clé dans les cycles biogéochimiques. Bien que l'effet du manteau neigeux en hiver dans la fonction et la composition des communautés bactériennes du sol ait été signalé, l'effet de la variation spatio-temporelle du manteau neigeux reste à étudier. Dans cette étude, nous avons caractérisé la dynamique spatio-temporelle des communautés bactériennes à partir de deux sites extrêmes selon un gradient de couvert neigeux. Pour cela, nous avons utilisé des approches moléculaires (SSCP et clonage / séquençage) et traditionnel (isolation par culture bactérienne). Les résultats présentés montrent que l'ensemble de la diversité bactérienne, sa composition et sa structure phylogénétique sont fortement liés à la durée de la couverture de neige. En outre, ces effets sont détectables au cours de la saison de végétation des plantes. Les facteurs biotiques et abiotiques (i.e. la sénescence des plantes et le pH du sol) jouent un rôle essentiel conduisant au regroupement de certaines bactéries en clades spécifiques (Acidobactéries, Actinobactéries, α-et β-Proteobactéries). Au cours de la saison de végétation des plantes, les clades de bactéries sont plus dispersés. La présente étude montre que, à un niveau taxonomique fin, la variation temporelle est un facteur plus important que la variation spatiale sur la diversité bactérienne. A un niveau taxonomique supérieur (i.e. sousphylum), la conclusion est inverse. Seule une petite fraction du total de la diversité bactérienne est cultivable et il se peut que certains groupes bactériens soient surreprésentés dans les plaques de culture. Cette étude apporte un nouvel éclairage sur le rôle de l'hiver et de la couverture neigeuse dans les distributions des communautés bactériennes. Cette étude peut-être utile pour prédire le comportement des bactéries dans les cycles des éléments nutritifs dans un contexte de réchauffement de la planète.
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Chang, Ching-Yuan, and 張競元. "Soil Nutrient Dynamics of Major Vegetation Types at Mt. Shei Alpine Ecosystem." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/42483039426839974955.
Full textAbstract:
碩士國立中興大學
森林學系所
100
The main objective of this study was to investigate the soil nutrient dynamics of five vegetation types at Mt. Shei alpine ecosystem. Five main collection points along the line of Mt. Shei were chosen (1) 2,500 m Chica-Cabin, with dominant species Neolitsea acuminatissima and Cyclobalanopsis stenophylla, (2) 2,800 m Crying-Slope, with dominant species Yushania niitakayamensis and Miscanthus transmorrisonensis, and with minor species Picea morrisonicola. (3) 3,200 m Burned Land, with dominant species Yushania niitakayamensis and Miscanthus transmorrisonensis. (4) 3,500 m Black Forest, with dominant species Abies kawakamii. (5) 3,650 m Land Cirque, with dominant species Juniperus squamata and Rhododendron pseudochrysanthum. Samples included litter layer, humus layer and soil of depth 0~10 cm, 20~10cm, 20~40 cm. These samples were weighed and analyzed with respect to their soil nutrients, and the factors which affected the observed soil nutrients were discussed. The results showed that the stone rate of the region varied significantly (between 0.98 to 25.54 %). Soil pH ranged between 3.65 to 5.16 which was highly acidic, and soil pH increased with increasing soil depth. The content of soil organic carbon was high (between 2.23 to 16.04%), and this was due to higher altitude, lower temperature and slower litter decomposition. Total soil nitrogen ranged between 0.07 to 1.22%, which was in normal concentrations and were suitable for plant growth. This means nitrogen is not a limiting factor for plant growth in this region. There was a strong positive correlation between total soil nitrogen and soil organic carbon, and the C/N ratio ranged between 11.0 to 33.3. Most of the sampling points were in the range of net mineralization. Soil available phosphorus concentration ranged between 0.26 to 8.40 ppm. The majority of the sampling points demonstrated phosphorous deficiency, with the exception of burned soil, in which a higher concentration of phosphorous was observed. The soil cation exchange capacity was very high (between 5.57 to 49.20 m.e. /100g), and exhibited a positive correlation with organic carbon as well as total nitrogen. The exchangeable potassium, sodium, calcium and magnesium are very low. The base saturation ranged between 1.4 to 13.92%, in which Crying-Slope and Burned Land exhibited significantly higher values than those of other sampling points (p<0.05). The exchangeable aluminum was high in the all regions (between 2.02 to 13.28 m.e. /100g). In summary, it was observed that the lowest value of stone rate, soil organic carbon, soil nitrogen and CEC was all from the sampling points in the highest Chica-Cabin of Land Cirque. This leads to the conclusion that most of the nutrients described in this study with the exception of exchangeable aluminum showed a trend, viz the amounts of nutrients reduced with increased soil depth.
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Zinger, Lucie. "Variations spatio-temporelle de la microflore des sols alpins." Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-00421411.
Full textAbstract:
Les micro-organismes jouent un rôle crucial dans les processus écosystémiques. L'étude de la distribution spatio-temporelle des communautés microbiennes est donc nécessaire, particulièrement dans un contexte de changements globaux. Les micro-organismes étant très diversifiés et majoritairement non cultivables, l'étude de leur diversité et des facteurs responsables de l'assemblage des communautés nécessite des outils adaptés. Les écosystèmes alpins montrent de forts gradients mésotopographiques et de régimes d'enneigements. Ces gradients engendrent une hétérogénéité spatiale du couvert végétal et des processus écosystémiques à des échelles réduites. Les contrastes de l'étage alpin s'appliquent aussi dans le temps, ceux-ci étant soumis à des froids intenses en hiver. Ces écosystèmes sont donc un modèle de choix pour l'étude des patrons spatio-temporels de la microflore du sol. Ce travail s'est d'abord concentré sur l'optimisation d'une technique d'empreinte moléculaire, la CESSCP, mais aussi d'outils statistiques pour l'analyse de séquences d'ADN. Les communautés bactériennes, fongiques et crenarchaeotes du sol ont été suivies deux années, par CE-SSCP et clonage/séquençage, dans deux habitats contrastés par leurs régimes d'enneigements. Cette étude a ensuite été étendue à l'échelle du paysage, sous divers couverts végétaux. Ce travail montre que l'assemblage des communautés microbiennes alpines varie au cours des saisons et que l'hiver constituent un fort évènement sélectif. Cette étude montre également que les communautés microbiennes sont spatialement distribuées en fonction des régimes d'enneigements et de la végétation. Les facteurs directement responsables de tels patrons sont discutés.
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DVORSKÝ, Miroslav. "Ecology of alpine plants in NW Himalaya." Doctoral thesis, 2014. http://www.nusl.cz/ntk/nusl-172974.
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The westernmost spur of the Tibetan Plateau stretches to Eastern Ladakh in India. It is a region which remains poorly explored because of challenging conditions and long periods of political instability. At the same time, it is one of the highest places on earth supporting angiosperm life, which goes beyond 6000 m a.s.l. here. The whole region, due its remoteness, is practically unaffected by plant invasions and direct human activities. Thus, Ladakh represents a kind of "natural experiment", providing very long gradient of elevation suitable for comparative functional ecology as well as for testing various hypotheses concerning limitations of vascular plants. Arid climate and extreme elevations are the common factors. Our team pursued the goal of systematic botanical and ecological exploration of Ladakh, started by late Leoš Klimeš. This thesis provides insight into the main vegetation types, clonality in plants, plant-plant interactions and soil phototroph communities.
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Wey, Tsong-Huei, and 魏聰輝. "The studies on the characteristics of apparent soil heat budget in Tatachia alpine ecosystem." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/20764231645594436172.
Full textAbstract:
博士國立臺灣大學
森林學研究所
90
In three permanent plots of Tatachia area, spruce forest plot(Picea morrisonicola Hay.), hemlock forest plot(Tsuga chinensis (Franch.) Pritz.) and meadow plot (Yushania niitakamensis (Hay.) Keng), we measured soil temperature at soil depths of 0.05 and 0.10 m, and collected data of thermal flow at soil depth of 0.05 m. Estimations using equation of Fourier’s law found that soil thermal conductivity was 1.094 Jm-1oC-1S-1 in spruce forest plot, 1.360 Jm-1oC-1S-1 in hemlock forest plot and 1.594 Jm-1oC-1S-1 in meadow plot. These values are comparable to those (0.17-18.20 Jm-1oC-1S-1) reported by pronounced scientists from other countries. Soil temperatures data were collected in soil depths of 0.05, 0.1, 0.2, 0.3, 0.5 and 1.0 m at two meteorological observatories of the Tatachia Alpine Long Term Ecosystem Research (LTER), Kuan-Shan Observatory and Spruce Forest Observatory, respectively. After harmonic analysis, the data were calculated with sinusoid equation to obtain soil thermal diffusivity of each depth and soil damping depth. Harmonic analysis provided that the mean square of the first and the second harmonic analysis in each depth is over 95 % of mean square of sequence and increases with increasing soil depth. The soil thermal diffusivity at Kuan-Shan Observatory ranges between 2.85 and 4.65×10-3cm2S-1, and at Spruce Forest Observatory ranges between 2.85×10-3 and 1.13×10-2 cm2S-1, respectively. The estimated value of soil thermal diffusivity also increases with increasing soil depth. The damping depth of both observatories was 169 cmYr-1, suggesting that in this area annual amplitude of soil surface temperature disappeared in the mentioned depth. In order to prevent the freezing of the water source transported within the pipes, the pipes should be buried at this depth. This study used the gradient method to estimate the heat flux of soil surface in Kuanshan, spruce forest, meadow plot (east aspect), Lintze Mt.(north aspect) and Lulin Mt.(south aspect) observatories in order to examine the differences resulted by elevation, orientation and canopy. The results revealed that average annual net value of soil heat flux was smaller at middle altitude (-68.85 MJm-2) than at higher altitude (-49.28 MJm-2), and the same pattern for average annual amplitude, 14.38 and 37.12 MJm-2 respectively. The average annual net value was the greatest on the north aspect (-23.30 MJm-2), the intermediate on the south aspect (-74.09 MJm-2) and the least on the east aspect (-74.66 MJm-2), and the average annual amplitude was 37.12, 44.34 and 41.68 MJm-2 respectively. The average annual amplitude was 37.12 MJm-2 in grassland of Lintze Mt. and 10.97 MJm-2 in spruce forest. The average annual amplitude was reduced by 70 % by the forest canopy, clearly showing the efficiency of forest canopy to buffer the temperature.
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Wang, Ming-Jen, and 王明仁. "Relationship between soil microbial biomass, acid phosphatase activity and bioavailable phosphorus at Ta-Ta-Chia alpine forest ecosystem." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/09231849964925604893.
Full textAbstract:
碩士國立臺灣大學
農業化學研究所
90
There are lacks of fertility as limiting factor for plant growth due to non- fertilizer in several natural ecosystems in worldwide. The lack of phosphorus causes the limiting plant growth in natural environment. The limit amount of phosphorus supply was present in natural environment and limit in bioavailability P for plant growth. Thus, the mineralization of organic P is an important source for P supply. There are two pathways concerning the mineralization of P: (1) inorganic P was transformed from microbial activity, and (2) inorganic P was transformed by soil enzyme reaction. The objectives of this study were focused on the Ta-Ta-Chia forest ecosystem. Liters input in soils and reduce the activity of plant physiology in winter. Liters were decomposed by soil microbes, and to investigate the bioavailability P contents correlated with microbial biomass, activity of acid phosphates, vegetation in situ, slop and microclimate. This study selected four sites. Every site collected six samples each time. The four sites are: (site 1) grassland of upper slope, (site 2) mixed forest with slope accumulate materials in down slope, (site 3) mixed forest without slope accumulate materials in flat location, (site 4) yushania. The results indicated that the slope can cause the nutrient accumulation. The amount of microbial biomass and acid phosphatase in down slopes of mixed forest site (site 2)and yushania (site 4) were grater than the grassland of upper slope (site 1), and shown significant differences (p<0.05). It is shown the same trend of the amount of bioavailability P with respect to slope (p<0.05). On the other hand, in the same elevation of mixed forest site (site 2) and yushania site (site 4), mixed forest site (site 2) contained more soil microbial biomass and higher phosphatase activity (P<0.05), but it is shown slightly difference of microbial biomass and bioavailability P. In comparison of slope of the same vegetation, the amount of microbial biomass and phosphatase in slope area were grater than that of flat site. The temporal variation indicated that bioavailability P significantly increase in autumn and winter, and not significant differences in spring and summer due to plant uptake P in spring and summer. From this study, bioavailability P showed different correlation with microbial biomass and activity of soil acid phosphatase. The R2 are equal to 0.858 and 0.782, respectively.