Environment and Floristics of Ten Australian Alpine Vegetation Formations

1999 ◽  
Vol 47 (1) ◽  
pp. 1 ◽  
Author(s):  
J. B. Kirkpatrick ◽  
K. L. Bridle
Keyword(s):  
Environmental Variables ◽  
Geographic Range ◽  
Previous Literature ◽  
Alpine Vegetation ◽  
Environmental Relationships ◽  
Alpine Zone ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
Extractable Phosphorus

Data on floristics, structure and environment were collected from quadrats throughout the geographic range of alpine vegetation in Australia. These data were used to explore the floristic and environmental relationships of ten alpine vegetation formations: bolster heath, coniferous heath, heath, alpine sedgeland, fjaeldmark, tall alpine herbfield, short alpine herbfield, grassland, bog and fen. Alpine sedgeland and coniferous heath, and tall alpine herbfield and grassland, proved to be closely similar in their floristics. Grassland and coniferous heath were most separated in ordination space. The environmental variables with the largest numbers of significant differences between formations were extractable phosphorus, summer temperatures, winter temperatures and topography. However, many other edaphic, climatic, topographic and biotic variables were important in discriminating between formations. The results of the formation-environment analyses were largely consistent with the relationships suggested in the previous literature. However, some environmental differences between formations that were observed or posited from local studies did not prove to be exportable to the alpine zone as a whole. Edaphic and topographic variables appear to be more important in discriminating the environments of alpine formations than the environments of alpine floristic communities.

Explaining the distribution, structure and species composition of snow-patch vegetation in Tasmania, Australia

2016 ◽  
Vol 64 (6) ◽  
pp. 484 ◽  
Author(s):  
Jared Parry ◽  
Jamie B. Kirkpatrick ◽  
Jon Marsden-Smedley
Keyword(s):  
Species Composition ◽  
Environmental Conditions ◽  
Vegetation Cover ◽  
Alpine Vegetation ◽  
Environmental Relationships ◽  
Structural Variability ◽  
North East ◽  
Alpine Zone ◽  
Surrounding Areas ◽  
High Degree

The term ‘snow patch’ indicates an area in an alpine zone with distinct vegetation because snow persists there longer than in the surrounding areas. Snow patches are a well known rare and threatened ecosystem on mainland Australia, but little is known of their distribution and vegetation in Tasmania. We describe, and determine the environmental relationships of, snow patches and their vegetation in Tasmania. There are 119 snow patches in Tasmania, covering 86 ha in toto, 43 of which have some fjaeldmark vegetation and the rest of which have a complete vegetation cover. Snow patches are confined to the taller, more continental mountains where they occur on north-east- to east-facing slopes, with the surrounding alpine vegetation usually being free of persistent snow. Their considerable floristic and structural variability relates to substrate and climate. Within Tasmania, several species are largely restricted to snow patches. The high degree of Tasmanian endemism in the snow-patch vegetation makes it distinct from the snow-patch vegetation of mainland Australia. The Tasmanian snow patches are also distinct in their environmental conditions. In Tasmania, snow does not usually persist over the winter outside the 119 snow patches. There are five floristic communities in these patches, all being distinct from those in mainland Australian snow patches. The Tasmanian snow patches merit listing as a threatened ecosystem on the basis of their distinctiveness and restricted extent.

Vascular plants distribution in relation to topography and environmental variables in alpine zone of Kedarnath Wild Life Sanctuary, West Himalaya

2018 ◽  
Vol 15 (9) ◽  
pp. 1936-1949
Author(s):  
Sudeep Chandra ◽  
Ankit Singh ◽  
C. P. Singh ◽  
M. C. Nautiyal ◽  
L. S. Rawat
Keyword(s):  
Environmental Variables ◽  
Vascular Plants ◽  
Alpine Zone ◽  
West Himalaya ◽  
Wild Life

THE EFFECTS OF TEMPERATURE ON THE OXYGEN CONSUMPTION, HEART RATE AND DEEP BODY TEMPERATURE DURING DIVING IN THE TUFTED DUCK AYTHYA FULIGULA

1992 ◽  
Vol 163 (1) ◽  
pp. 139-151 ◽  
Author(s):  
R. M. BEVAN ◽  
P. J. BUTLER
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Deep Body Temperature ◽  
Tufted Duck ◽  
Winter Conditions ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
The Mean ◽  
Maintain Body Temperature ◽  
Deep Body

Six tufted ducks were trained to dive for food at summer temperatures (air, 26°C, water, 23°C) and at winter temperatures (air, 5.8°C, water 7.4°C). The mean resting oxygen consumption (Voo2) a t winter temperatures (rwin) was 90% higher than that at summer temperatures (Tsum), but deep body temperatures (Tb) were not significantly different. Diving behaviour and mean oxygen consumption for dives of mean duration were similar at Twin and at Tsum, although the mean oxygen consumption for surface intervals of mean duration was 50% greater at Twin and Tb was significantly lower (1°C) at the end of a series of dives in winter than it was in summer. There appears to be an energy saving of 67 J per dive during winter conditions and this may, at least partially, be the result of the metabolic heat produced by the active muscles being used to maintain body temperature. While at rest under winter conditions, this would be achieved by shivering thermogenesis. Thus, the energetic costs of foraging in tufted ducks in winter are not as great as might be expected from the almost doubling of metabolic rate in resting birds.

Cores and Peripheries Revisited: The Mining Landscapes of Wadi Faynan (Southern Jordan) 5000 BC–AD 700

2007 ◽  
Author(s):  
Graeme Barker ◽  
David Mattingly
Keyword(s):  
Roman Empire ◽  
Iron Age ◽  
Summer Temperature ◽  
Research Interest ◽  
Annual Rainfall ◽  
Winter Temperatures ◽  
Mountain Front ◽  
Summer Temperatures ◽  
The Mean ◽  
Landscape Survey

One of Barry Cunliffe’s major areas of research interest has been societies in transition, especially in the context of core/periphery relationships between expanding states and societies on their margins. Much of this work has been on the relationships between Rome and the Iron Age societies of southern Britain on the northwestern margins of the empire, and the subsequent pathways of resistance, interaction, and transformation. In this chapter we focus on events and processes on the opposite margins of the Roman empire in the Levant, where the Nabataean state was formally incorporated into the Roman imperial system some sixty years after the Claudian invasion of Britain. We draw on the results of the Wadi Faynan Landscape Survey (1996–2000), an interdisciplinary and diachronic investigation of evidence of environmental and climatic change, settlement pattern, and human activity in the Wadi Faynan in southern Jordan (figure 7.1). Situated about 40 kilometres from the Nabataean capital of Petra, the Wadi Faynan lies in the hot and hyper-arid Jordanian Desert, at a distinctive and spectacular mountain front that reaches 1500m above the desert floor. This landform marks the eastern margin of the desert lowlands of the great Jordanian rift valley, with the trough of the Wadi ‘Arabah to the south and west, and the highlands of the Mountains of Edom and the Jordanian tablelands to the east and north (Bienkowski and Galor 2006). The mean summer temperature on the Jordanian tablelands is in the order of 178c, compared with winter temperatures of about 12ºc (Bruins 2006; Rabb’a 1994). Winter temperatures on the desert floor in the Wadi Faynan are much the same as on the plateau, but in summer temperatures frequently reach 40ºc. Seasonality is strong, with most rain falling between December and March and virtually no precipitation occurring between June and September. Annual rainfall in the lower Wadi Faynan is around 63mm and even less in theWadi ‘Arabah (‘Aqaba receives 30mm for example), whereas the Jordanian Tablelands have an average precipitation exceeding 200mm per year.

scholarly journals Increased wave action promotes muscle performance but increasing temperatures cause a tenacity–endurance trade-off in intertidal snails (Nerita atramentosa)

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Samuel Clayman ◽  
Frank Seebacher
Keyword(s):  
Maximum Stress ◽  
Citrate Synthase ◽  
Wave Action ◽  
Sea Surface ◽  
Muscle Performance ◽  
Trade Off ◽  
Physiological Capacity ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
Physical Impact

Abstract Concurrent increases in wave action and sea surface temperatures increase the physical impact on intertidal organisms and affect their physiological capacity to respond to that impact. Our aim was to determine whether wave exposure altered muscle function in intertidal snails (Nerita atramentosa) and whether responses to wave action and temperature are plastic, leading to compensation for altered environmental conditions. We show that field snails from exposed shores had greater endurance and vertical tenacity than snails from matched protected shores (n = 5 pairs of shores). There were no differences in muscle metabolic capacities (strombine/lactate dehydrogenase, citrate synthase and cytochrome c oxidase activities) between shore types. Maximum stress (force/foot area) produced by isolated foot muscle did not differ between shore types, but foot muscle from snails on exposed shores had greater endurance. A laboratory experiment showed that vertical tenacity was greater in animals acclimated for 3 weeks to cool winter temperatures (15 C) compared to summer temperatures (25 C), but endurance was greater in snails acclimated to 25°C. Acclimation to water flow that mimicked wave action in the field increased vertical tenacity but decreased endurance. Our data show that increased wave action elicits a training effect on muscle, but that increasing sea surface temperature can cause a trade-off between tenacity and endurance. Ocean warming would negate the beneficial increase in tenacity that could render snails more resistant to acute impacts of wave action, while promoting longer term resistance to dislodgment by waves.

Use of bioclimatic analysis to direct survey effort for the long-footed potoroo (Potorous longipes), a rare forest-dwelling rat-kangaroo

2002 ◽  
Vol 29 (2) ◽  
pp. 193 ◽  
Author(s):  
A. W. Claridge
Keyword(s):  
Environmental Variables ◽  
New Records ◽  
New South ◽  
New South Wales ◽  
Geographic Range ◽  
Suitable Habitat ◽  
The Past ◽  
South Wales ◽  
North Eastern ◽  
Survey Effort

The long-footed potoroo (Potorous longipes) is one of the rarest and most elusive forest-dwelling mammals in Australia. Survey effort for the species over the past decade or so in south-eastern New South Wales has been driven, primarily, by predictions derived from climatic analyses using BIOCLIM. These predictions were based on known locality records of the long-footed potoroo from adjacent East Gippsland, Victoria. While they have proven useful in confirming the occurrence of the species in New South Wales, recent fortuitous records of the species from north-eastern Victoria fall well outside of the range predicted earlier by BIOCLIM. Using these new records a revised predicted range is calculated, enlarging considerably the potential geographic extent of climatically suitable habitat for the species. The results presented here highlight the limitations of BIOCLIM when given locality records of a species from only a portion of its true geographic range. I argue that less emphasis might be based on this approach to direct survey effort for the species in the future. Instead, a range of other environmental variables might be used in combination with BIOCLIM-derived outputs when selecting survey sites. In this way a more representative picture of the distribution of the species may be obtained.

Population Dynamics and Food Habits of Bluegill (Lepomis macrochirus) in a Thermally Stressed Reservoir

1991 ◽  
Vol 48 (5) ◽  
pp. 768-775 ◽  
Author(s):  
Barbara E. Taylor ◽  
John M. Aho ◽  
Diane L. Mahoney ◽  
Ruth A. Estes
Keyword(s):  
South Carolina ◽  
Breeding Season ◽  
Nuclear Reactor ◽  
Lepomis Macrochirus ◽  
Thermal Conditions ◽  
Savannah River ◽  
Cooling Reservoir ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
River Site

Bluegill (Lepomis macrochirus) is the dominant fish species in a 67-ha cooling reservoir for a nuclear reactor on the Savannah River Site in South Carolina. Mortality and breeding season of bluegill were strongly influenced by reactor operations, which often produced temperatures of 40–60 °C in portions of the reservoir. Late spring and summer reactor operations caused ~ 90% mortality of bluegill. This mortality was largely associated with reactor restarts. Survivors occupied small thermal refuges in coves. Elevated fall and winter temperatures allowed an extended breeding season, although extremely high summer temperatures appeared to inhibit breeding. Bluegill depended primarily on benthic food resources, including dipterans and microcrustaceans. Despite the great variation in environmental conditions and diets, body condition of surviving bluegill was nearly constant between April 1985 and January 1986. Factors that contribute to the success of bluegill in this system include high thermal tolerance, broad diets, and an ability to breed when thermal conditions are appropriate, regardless of season.

scholarly journals Food ingestion and assimilation by Hyale media (Dana, 1853) (Crustacea - Amphipoda)

1990 ◽  
Vol 38 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Airton Santo Tararam ◽  
Hilda de Souza Lima Mesquita ◽  
Yoko Wakabara ◽  
Clóvis A Peres
Keyword(s):  
Developmental Stages ◽  
Specific Growth ◽  
Assimilation Efficiency ◽  
Effect Of Temperature ◽  
Adult Males ◽  
Food Ingestion ◽  
Young Males ◽  
Physiological Conditions ◽  
Winter Temperatures ◽  
Summer Temperatures

The feeding of Hyale media was analysed under laboratory conditions in winter and summer temperatures. The results showed that assimilation rates increased following food ingestion rates and decreased when egestion rates increased. In winter temperatures no significant differences were found in the assimilation rates among developmental stages and sexes. In summer temperatures assimilation rates for ovigerous and non-ovigerous females were higher than those found for adult and young males. Although not statistically analysed, mean assimilation efficiencies were highest among ovigerous females and adult males, in summer. The quantitative and qualitative variations found in the assimilation efficiency and rates were explained by the differential effect of temperature on the specific growth rate and in the physiological conditions of each growth stage concerned.

Geochemical and Geophysical Constraints on Life’s Origin

2019 ◽  
Author(s):  
David W. Deamer
Keyword(s):  
Origin Of Life ◽  
Liquid Water ◽  
Global Scale ◽  
Global Temperature ◽  
Death Valley ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
The Origin Of Life ◽  
Continuous Chemical ◽  
Hydrothermal Fields

Bernal's quote is a bit wordy, but he was basically saying that life can be understood as a continuous chemical reaction, and I agree. Throughout this book I will be describing ideas about how life can begin on habitable planets, which are defined as planets with orbits not too close and not too far from a star so that the temperature permits liquid water to exist. The conditions in which life can begin must have sufficient complexity to permit primitive life to assemble from organic chemicals dispersed in a sterile environment which then begin to react and evolve into more complex structures. This chapter will describe the main parameters of geochemical and geophysical complexity, and then consider them in terms of scales from the nanoscopic to the macroscopic. Questions to be addressed: What scales must be considered to understand how life can begin? What are the properties of the scales? How do the scales relate to the origin of life? The physical dimensions related to the origin of life can be described in terms of four scales—global, local, microscopic, and nanoscopic— and these dimensions must be related to the chemical and physical properties of each scale. The global scale is easiest to understand because the parameters are averages of very broad variables. For instance, we can state that the global temperature today is 15° C and even follow changes in the temperature to accuracies of a tenth of a degree on a year to year basis. However, within the global scale are extreme variations between winter temperatures of - 60° C at the poles and summer temperatures of 50° C in Death Valley, California. Of course, even higher temperatures are associated with hydrothermal fields, up to boiling at 100° C, but sometimes nearer to 90° C because the fields are usually at higher elevations associated with volcanoes. Table 2.1 summarizes the main parameters of the global scale on Earth and Mars today and compares their values with those near the time that life began on the Earth 4 billion years ago.

Late Pleistocene climatic change in the French Jura (Gigny) recorded in the δ18O of phosphate from ungulate tooth enamel

2011 ◽  
Vol 75 (3) ◽  
pp. 605-613 ◽  
Author(s):  
Magali Fabre ◽  
Christophe Lécuyer ◽  
Jean-Philip Brugal ◽  
Romain Amiot ◽  
François Fourel ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Cervus Elaphus ◽  
Red Deer ◽  
Tooth Enamel ◽  
Large Mammals ◽  
Air Temperatures ◽  
Winter Temperatures ◽  
French Jura ◽  
Summer Temperatures ◽  
Interdependent Relationships

AbstractOxygen isotope compositions of phosphate in tooth enamel from large mammals (i.e. horse and red deer) were measured to quantify past mean annual air temperatures and seasonal variations between 145 ka and 33 ka in eastern France. The method is based on interdependent relationships between the δ18O of apatite phosphate, environmental waters and air temperatures. Horse (Equus caballus germanicus) and red deer (Cervus elaphus) remains have δ18O values that range from 14.2‰ to 17.2‰, indicating mean air temperatures between 7°C and 13°C. Oxygen isotope time series obtained from two of the six horse teeth show a sinusoidal-like signal that could have been forced by temperature variations of seasonal origin. Intra-tooth oxygen isotope variations reveal that at 145 ka, winters were colder (− 7 ± 2°C) than at present (3 ± 1°C) while summer temperatures were similar. Winter temperatures mark a well-developed West–East thermal gradient in France of about − 9°C, much stronger than the −4°C difference recorded presently. Negative winter temperatures were likely responsible for the extent and duration of the snow cover, thus limiting the food resources available for large ungulates with repercussions for Neanderthal predators.

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