Дисертації з теми "Alpine soils"
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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.
Повний текст джерелаPapanikolaou, 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.
Повний текст джерелаShrestha, 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.
Повний текст джерелаThis 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.
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.
Повний текст джерелаWu, 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.
Повний текст джерелаSquires, 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.
Повний текст джерелаJenkins, 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.
Повний текст джерелаMustafa, Tarfa. "Vers une comparaison métatranscriptomique entre deux sols alpins sous couvert nival contrasté." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENS020/document.
Повний текст джерелаThe 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
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.
Повний текст джерелаShahnavaz, Bahar. "Communautés bactériennes de sols alpins et filtres environnementaux." Grenoble 1, 2009. http://www.theses.fr/2009GRE10331.
Повний текст джерелаBacteria 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
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.
Повний текст джерелаThe 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
Zinger, Lucie. "Variations spatio-temporelles de la microflore des sols alpins." Université Joseph Fourier (Grenoble), 2009. http://www.theses.fr/2009GRE10122.
Повний текст джерелаMicroorganisms 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
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.
Повний текст джерелаWestbrook, 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.
Повний текст джерелаBressan, 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.
Знайти повний текст джерелаMeier, 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.
Повний текст джерелаGlenn, 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.
Повний текст джерелаOne 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.
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.
Повний текст джерелаCharcoal 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
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.
Повний текст джерелаNyberg, 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.
Повний текст джерелаMüller, 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.
Повний текст джерелаMüller, 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.
Повний текст джерелаRippin, 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.
Повний текст джерелаHowes, 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.
Знайти повний текст джерелаFuchs, 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.
Повний текст джерелаPermafrost 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.
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.
Повний текст джерелаBhople, 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.
Повний текст джерелаPech, 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.
Повний текст джерелаBogna, 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
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.
Повний текст джерелаThe 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
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.
Повний текст джерелаPascual, 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.
Повний текст джерелаRist, 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.
Повний текст джерелаGrossi, 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.
Повний текст джерелаChiffard, Jules. "Oiseaux chanteurs des milieux ouverts de montagne et changements globaux." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEP038.
Повний текст джерелаGrowth 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
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.
Повний текст джерелаLake 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
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.
Повний текст джерелаThis 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
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.
Повний текст джерелаSue, 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.
Повний текст джерелаBrau-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.
Повний текст джерелаCheng, 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.
Повний текст джерела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.
"Sexual reproductive processes of plants in an alpine tundra environment." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-04-2063.
Повний текст джерелаChen, 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.
Повний текст джерела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.
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.
Повний текст джерела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.
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.
Повний текст джерелаShahnavaz, Bahar. "Communauté bactérienne de sols alpins et filtres environnementaux." Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-00515414.
Повний текст джерелаChang, 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.
Повний текст джерела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.
Zinger, Lucie. "Variations spatio-temporelle de la microflore des sols alpins." Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-00421411.
Повний текст джерелаDVORSKÝ, Miroslav. "Ecology of alpine plants in NW Himalaya." Doctoral thesis, 2014. http://www.nusl.cz/ntk/nusl-172974.
Повний текст джерелаWey, 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.
Повний текст джерела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.
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.
Повний текст джерела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.