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An assessment of trampling impact on alpine vegetation, Fiordland and Mount Aspiring national parks, New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Environmental Science in the University of Canterbury /Squires, Carolyn. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 204-215). Also available via the World Wide Web.
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Alpine Soil Geomorphology: The Development and Characterization of Soil in the Alpine-Subalpine Zone of the Wallowa Mountains, OregonAllen, Charles Edward 09 October 1995 (has links)
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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Psychrotolerant mucoralean fungi present in pristine mountain fynbos soil and vineyard soil from the Stellenbosch regionSamson, Heidi E. (Heidi Estrelita) 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Mucoralean fungi are mostly saprotrophs that are frequently encountered in soil
habitats. Using an isolation temperature of circa 25°C, other workers obtained
these fungi from a wide diversity of geographical areas in southern Africa.
However, it is known that psychrotolerant mucoralean fungi, able to grow at
25°C as well as at 5°C, occur in pristine Alti Mountain Grassland. Nothing is
known about the diversity of these psychrotolerant soil fungi in other vegetation
types of South Africa.
Consequently, in this study, the psychrotolerant fungal taxa and numbers in soil
from a vineyard and from pristine Mountain Fynbos were determined using an
incubation temperature of 4°C and a complex isolation medium. The latter
contained agar, malt extract, peptone, yeast extract, penicillin and streptomycin
sulphate. Soil samples were analysed in late summer, autumn and mid-winter.
It was found that, for the samples taken in late summer and autumn, the
diversity of mucoralean species in the soil differed between fynbos and
vineyard. In winter however, no significant difference was detected between the
Shannon's diversity indices of mucoralean species in the soil samples taken
from the two habitats. It was found that in both soil types, the percentage
mucoralean fungi on the plates increased from summer to winter. In addition,
the numbers of detectable Morlierella subgenus Morlierella on the plates were
higher in winter than in late summer. The diversity of mucoralean species
obtained during winter in fynbos and vineyard soil was significantly less than the
diversity of these species in Alti Mountain Grassland soil.
To determine if the Morlierella subgenus Morlierella isolates from the fynbos
and vineyard soil, and those obtained from Alti Mountain Grassland, differ in the
ability to grow at low temperatures, the radial growth rate on malt extract agar at
4°C and BOC was determined for each isolate. The results indicate that not only
did seasonal changes occur in the taxa within Morlierella subgenus Morlierella,
but that the isolates dominating the soil in different seasons also differed in the
ability to grow at low temperatures. The percentage of isolates that had
reached greater colony diameters after B days of incubation at 4°C, was higher for the isolates obtained in the cold wet month of July than for those obtained in
the warmer dryer month of February. Similar results were obtained with the
radial growth experiments conducted at BOC. The Morlierella subgenus
Morlierella isolates obtained in winter from fynbos and vineyard soil showed
less variation in low temperature growth rate than the isolates of this taxon
obtained in winter from Alti Mountain Grassland soil during a previous study.
This variation corresponds to the greater number (20) of Morlierella subgenus
Morlierella species found in the grassland soil. Altogether only seven species
of this subgenus was detected during the present study in the fynbos and
vineyard soil samples. It was speculated that this difference in diversity
between the fynbos and vineyard isolates, and the grassland isolates obtained
in a previous study, might have been as a result of differences in the habitat or
the enumeration methods used.
The phylogenetic relationship between different psychrotolerant isolates of
Morlierella subgenus Morlierella originating from the soil of the fynbos, vineyard
and Alti Mountain Grassland, was subsequently determine through comparison
of ITS regions, within ribosomal RNA repeats. Consequently, 45
psychrotolerant Morlierella subgenus Morlierella isolates originating from the
three soil habitats was compared on the basis ITS 1 nucleotide sequence
composition and radial growth rate at 4°C. Phylogenetic analyses showed that
the isolates could be grouped into two clusters correlating with the ability to
grow at low temperatures. Each cluster was further subdivided into two
subgroups. It was found that except for one subgroup and the reference strain
occurring in another subgroup, all the subgroups contain isolates originating
from a single soil habitat. Therefore, the ITS 1 sequence of these fungi seems
to indicate the original habitat and ability to grow at low temperatures. This
correlation of the ITS sequence with the ecological habitat of a fungus has also
been observed by other workers for other fungal groups. / AFRIKAANSE OPSOMMING: Mucoraliese fungi is meestal saprotrofe wat dikwels in grondhabitatte aangetref
word. Deur gebruik te maak van 'n isolasietemperatuur van circa 25°C, het
ander werkers dié fungi van 'n wye verskeidenheid geografiese gebiede in
suidelike Afrika verkry. Dit is egter bekend dat die psigrotolerante mucoraliese
fungi, wat in staat is om by 2SoC en ook by SaC te groei, in ongeskonde Alti
Berg-Grasland voorkom. Niks is egter bekend oor die diversiteit van dié
psigrotolerante grondfungi in ander veldtipes van suidelike Afrika nie.
Die psigrotolerante fungustaksa en -getalle in grond van 'n wingerd en van
ongeskonde Berg Fynbos is gevolglik in dié studie bepaal deur gebruik te maak
van 'n inkubasietemperatuur van 4"C en 'n komplekse isolasiemedium.
Laasgenoemde het agar, moutekstrak, peptoon, gisekstrak, penisillien en
streptomisiensulfaat bevat. Grondmonsters is in die laatsomer, herfs en
midwinter geanaliseer. Daar is 'n verskil gevind tussen die diversiteit van die
mucoraliese spesies in die grond van fynbos en dié van wingerd in die monsters
wat in die laatsomer en midwinter geneem is. In die winter is daar egter geen
beduidende verskil gevind tussen die Shannon diversiteitsindekse van
mucoraliese spesies in die grondmonsters wat uit die twee habitatte getrek is
nie. In albei grondtipes is daar gevind dat die persentasie mucoraliese fungi op
die plate toegeneem het van somer tot winter. Daarby was die aantal
waarneembare Morlierella subgenus Morlierella op die plate meer in die winter
as in die laatsomer. Die diversiteit van mucoraliese spesies wat in die winter uit
fynbos- en wingerdgrond verkry is, was beduidend minder as die diversiteit van
dié spesies in Alti Berg-Grasland grond.
Om te bepaal of die Morlierella subgenus Morlierella isolate van die fynbos- en
wingerdgrond en dié van Alti Berg-Grasland van mekaar verskil ten opsigte van
hul vermoë om by lae temperature te groei, is die radiale groeitempo op
moutekstrak by 4"C en aoc vir elke isolaat bepaal. Die resultate dui aan dat
daar nie alleen seisoenale veranderinge in die taksa binne Morlierella subgenus
Morlierella voorkom nie, maar dat die isolate wat tydens verskillende seisoene
uit die grond verkry is, ook ten opsigte van hul groeivermoë by lae temperature van mekaar verskil. Die persentasie isolate wat groter kolonie diameters bereik
het ná B dae inkubasie by 4°C, was hoër vir die isolate van die koue, nat
Juliemaand as vir dié wat in die warmer en droër Februariemaand verkry is.
Soortgelyke resultate is verkry met radiale groei-eksperimente wat by BOC
gedoen is. Die MortierelIa subgenus MortierelIa isolate wat in die winter uit
fynbos- en wingerdgrond verkry is, het In kleiner variasie in hul groeitempo by
lae temperature getoon as die isolate in dié takson wat tydens 'n vorige studie
in die winter uit Alti Berg-Grasland grond verkry is. Dié variasie stem ooreen
met die groter aantal (20) MortierelIa subgenus MortierelIa spesies wat in die
graslandgrond gevind is. Slegs sewe spesies van dié subgenus is gedurende
die huidige studie in die fynbos- en wingerdgrondmonsters waargeneem. Daar
is gespekuleer dat dié verskil in diversiteit tussen die fynbos- en wingerdisolate
en die graslandisolate van die vorige studie die gevolg mag wees van verskille
tussen die habitat of die enumerasiemetodes wat gebruik is.
Die filogenetiese verwantskap tussen verskillende psigrotolerante isolate van
MortierelIa subgenus MortierelIa uit die grond van die fynbos, wingerd en Alti
Berg-Grasland, is vervolgens bepaal deur 'n vergelyking van interne
getranskribeerde spasieerder (ITS) areas, binne ribosomale RNS herhalings.
Daar is gevolglik 45 psigrotolerante MortierelIa subgenus MortierelIa isolate uit
die drie grondhabitatte met mekaar vergelyk op grond van die basis ITS 1
nukleotied opeenvolgingsamestelling en radiale groeitempo by 4°C.
Filogenetiese analises het die isolate in twee groepe verdeel op grond van hul
vermoë om by lae temperature te groei. Elke groep is verder in twee subgroepe
verdeel. Daar is gevind dat behalwe vir een subgroep en die verwysingstam
wat in 'n ander subgroep voorgekom het, elkeen van die subgroepe bestaan het
uit isolate wat van 'n enkele grond habitat verkry is. Dit wil dus voorkom of die
ITS 1 opeenvolging van dié fungi 'n aanduiding gee van die oorspronklike
habitat en die vermoë om by lae temperature te groei. Dié korrelasie tussen die
ITS opeenvolging en die ekologiese habitat van 'n fungus is ook deur ander
werkers vir ander fungusgroepe waargeneem.
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Caractérisation et stabilité de la matière organique du sol en contexte montagnard calcaire : proposition d'indicateurs pour le suivi de la qualité des sols à l'échelle du paysage / Characterization and stability of soil organic matter in calcareous mountain : proposal of indicators for soil quality monitoring at the landscape scaleSaenger, Anaïs 16 April 2013 (has links)
Les sols de montagne représentent d'importants réservoirs de carbone (C) potentiellement vulnérables aux changements climatiques et changements d'usage qui les affectent de manière amplifiée. Or la grande variabilité de ces milieux, leur faible accessibilité ainsi que le manque d'outils de mesure appropriés limitent nos connaissances qui restent aujourd'hui très fragmentaires en ce qui concerne les stocks, la chimie et la réactivité du carbone organique des sols (COS). Ces informations sont pourtant nécessaires pour appréhender l'évolution de ces sols et de leur C dans ce contexte de changements globaux. Les objectifs de ce travail de thèse étaient (i) d'accéder à une meilleure compréhension de la nature, de la stabilité et de la vulnérabilité du COS dans une mosaïque d'écosystèmes des Préalpes calcaires (massif du Vercors), (ii) de rechercher des outils de caractérisation rapides et fiables adaptés à l'étude et au suivi du COS à l'échelle du paysage, et enfin (iii) de proposer des indices pour l'évaluation et le suivi de la qualité des sols en milieu de montagne. Dans un premier temps, nous avons testé l'application de la pyrolyse Rock-Eval pour l'étude du COS à grande échelle sur un ensemble d'unités écosystémiques. Nous avons ensuite comparé la pyrolyse Rock-Eval à deux techniques classiques d'étude de la matière organique du sol (MOS) : le fractionnement granulodensimétrique de la MOS et la spectroscopie moyen infrarouge. Ces approches analytiques couplées nous ont permis de quantifier les stocks de C à l'échelle de la zone d'étude et d'expliquer la stabilité et la vulnérabilité du COS sous des angles variés. Les facteurs responsables des patrons observés dans les différentes unités écosystémiques sont discutés. Ce travail a également confirmé la pertinence de l'outil Rock-Eval pour répondre aux objectifs fixés. Parallèlement, des approches biologiques nous ont permis d'évaluer l'importance de la composante microbienne dans ces sols. Enfin, des indices évaluant le statut organique des sols (stockage de COS, fertilité des sols, vulnérabilité du COS) sont proposés pour constituer des outils de gestion et d'aide à la décision. / Mountain soils are major reservoirs of carbon (C), potentially vulnerable to climate and land use changes that affect them significantly. However, the great variability of these soils, their limited accessibility and the lack of appropriate measurement tools restrict our knowledge. Today, our comprehension of the biogeochemistry of mountain soils remains very incomplete regarding stocks, chemistry and reactivity of soil organic carbon (SOC). Yet this information is necessary to understand the evolution of soil carbon in the current context of global change. The objectives of this work were (i) to gain a better understanding of the nature, stability and vulnerability of SOC in a mosaic of ecosystems in a calcareous massif in the Alps (Vercors massif), (ii) to search for fast and reliable characterization tools, suitable for the study and monitoring of COS at the landscape scale, and (iii) to propose indicators for the assessment and monitoring of soil quality in mountain regions. As a first step, we tested the application of Rock-Eval pyrolysis for the study of COS at large-scale on a set of ecosystem units. Then, we compared the Rock-Eval approach to two conventional techniques for soil organic matter (SOM) study: the particle-size fractionation of SOM, and the mid-infrared spectroscopy. These coupled analytical approaches allowed us to quantify C stocks across the study area, and explain the stability and the vulnerability of COS at various angles. Factors responsible for the patterns observed in the different eco-units are discussed. This work also confirmed the relevance of the Rock-Eval tool to achieve our previous objectives. Biological approaches allowed us to assess the significance of microbial pool in these soils. Finally, indices assessing the status of SOM (SOC storage, soil fertility, vulnerability COS) were proposed and constituted interesting management tools for decision-makers.
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