scholarly journals A Relation Between Snow Cover, Cirrus Cloud, and Freezing Nuclei in the Atmosphere

1956 ◽  
Vol 9 (4) ◽  
pp. 545 ◽  
Author(s):  
EG Bowen
Keyword(s):  
Snow Cover ◽  
Western Australia ◽  
Cirrus Cloud ◽  
Nucleus Concentration ◽  
High Degree ◽  
Calendar Dates

It is reasonable to suppose that observations like that of cirrus cloud in the upper air and heavy falls of snow in relatively warm latitudes correspond to the presence of a large number of freezing nuclei in the atmosphere. A 300-year record of snow covering the ground at Tokyo and a 10-year record of cirrus cloud in Western Australia are examined and compared with one year's measurement of freezing nucleus concentration. The curves show a high degree of correlation, and all three tend to maximize on certain calendar dates.

Corrigendum to: Drosera × sidjamesii (Droseraceae): systematics and ecology of a natural hybrid from Western Australia

2007 ◽  
Vol 20 (2) ◽  
pp. 186
Author(s):  
Allen Lowrie ◽  
John G. Conran
Keyword(s):  
Western Australia ◽  
Parental Species ◽  
Elevation Gradient ◽  
Natural Hybrid ◽  
Peat Soils ◽  
Cytological Examination ◽  
White Sand ◽  
Water Field ◽  
Almost All ◽  
High Degree

The natural hybrid Drosera � sidjamesii Lowrie & Conran from Lake Gnangarra north of Perth, Western Australia is described and defined as a cross between D. nitidula Planch. subsp. omissa Marchant & Lowrie auct. non Diels and D. pulchella Lehm., between which it shows a high degree of intermediacy for almost all characters. Cytological examination of the hybrid and its parents confirms that the former at 2n = 46 is a combination of the 2n = 28 in D. nitidula subsp. omissa and 2n = 18 in D. pulchella. The hybrid grows along a narrow ecotone between the parental species, largely on sandy peat and along a presumed soil moisture/elevation gradient caused by the nearby lake. Nevertheless, within this ecotone the hybrid is significantly more frequent than either parental species, with D. pulchella mainly growing in peat soils closer to the lake and D. nitidula subsp. omissa on white sand further from the water. Field observations of morphotypes also suggest that the hybrid has arisen several times at the site, and that a limited number of plants at the site are becoming fertile and setting seed.

Drosera × sidjamesii (Droseraceae): systematics and ecology of a natural hybrid from Western Australia

2007 ◽  
Vol 20 (1) ◽  
pp. 44 ◽  
Author(s):  
Allen Lowrie ◽  
John G. Conran
Keyword(s):  
Western Australia ◽  
Parental Species ◽  
Elevation Gradient ◽  
Natural Hybrid ◽  
Peat Soils ◽  
Cytological Examination ◽  
White Sand ◽  
Water Field ◽  
Almost All ◽  
High Degree

The natural hybrid Drosera × sidjamesii Lowrie & Conran from Lake Gnangarra north of Perth, Western Australia is described and defined as a cross between D. nitidula Planch. subsp. omissa Marchant & Lowrie auct. non Diels and D. pulchella Lehm., between which it shows a high degree of intermediacy for almost all characters. Cytological examination of the hybrid and its parents confirms that the former at 2n = 46 is a combination of the 2n = 28 in D. nitidula subsp. omissa and 2n = 18 in D. pulchella. The hybrid grows along a narrow ecotone between the parental species, largely on sandy peat and along a presumed soil moisture/elevation gradient caused by the nearby lake. Nevertheless, within this ecotone the hybrid is significantly more frequent than either parental species, with D. pulchella mainly growing in peat soils closer to the lake and D. nitidula subsp. omissa on white sand further from the water. Field observations of morphotypes also suggest that the hybrid has arisen several times at the site, and that a limited number of plants at the site are becoming fertile and setting seed.

B1 subdivisions in thin komatiites at Kambalda, Western Australia

1989 ◽  
Vol 126 (3) ◽  
pp. 263-270 ◽  
Author(s):  
B. Thomson
Keyword(s):  
Western Australia ◽  
Late Stage ◽  
Lateral Position ◽  
Total Thickness ◽  
Olivine Cumulates ◽  
High Degree ◽  
Peripheral Regions

AbstractB1 subdivisions are narrow foliated zones of stubby, skeletal olivine blades, situated at the top of the granular olivine cumulates (B2) in ponded komatiite lavas. They developed at a late stage in pond crystallization as a result of compaction-related circulation of intercumulus liquids through and along the top of the cumulates. The total thickness of a B1 and its degree of blade parallelism are related to lateral position within ponded lavas. The deeper, hotter and longer-lived core regions generated a thick B1 with a high degree of blade parallelism (ordered B1), whereas the shallower, peripheral regions produced a narrow B1 with a poor degree of blade parallelism (disordered B1), or failed to develop one at all.

Genetic diversity and the utilisation of Acacia species complexes in agroforestry in Western Australia

2003 ◽  
Vol 16 (1) ◽  
pp. 49 ◽  
Author(s):  
M. Byrne ◽  
L. Broadhurst
Keyword(s):  
Western Australia ◽  
Native Species ◽  
Genetic Relationships ◽  
Dryland Salinity ◽  
Woody Perennials ◽  
Woody Perennial ◽  
Acacia Species ◽  
Species Complexes ◽  
Agricultural Areas ◽  
High Degree

Dryland salinity is a major problem in the agricultural areas of Western Australia, having significant detrimental impacts in both agricultural and non-agricultural arenas. Development of new woody perennial tree crops is an option for recharge control in the management of salinity and there is a focus on development of native species that are adapted to low-rainfall areas, with potential for commercial production. Acacia is an important genus for utilisation of woody perennials as there is a large number of species occurring in a wide variety of habitats, and many Acacia species are utilised throughout the world for a range of purposes. In Western Australia, the following three species are of interest for development for commercial utilisation in agroforestry plantings: A.�microbotrya, A. acuminata and A. saligna. All three species show a high degree of morphological variation and are likely to consist of several taxa. Lack of understanding of taxonomic entities and their genetic relationships will hinder the utilisation and development of these species. A combined genetic and taxonomic study has defined the morphological and genetic variation within the A. acuminata complex and identified several taxa. Similar studies will also be expected to define taxa within the A. microbotrya and A. saligna complexes.

Protein digestibility in sheep and cattle in north-western Australia

1968 ◽  
Vol 8 (33) ◽  
pp. 419 ◽  
Author(s):  
DW Robinson ◽  
GA Stewart
Keyword(s):  
Western Australia ◽  
Crude Protein ◽  
Protein Digestibility ◽  
Research Station ◽  
Digestible Crude Protein ◽  
The Difference ◽  
Protein Rich ◽  
High Degree ◽  
The Relationship ◽  
North Western

Three experiments were conducted at Kimberley Research Station, Western Australia, one with local Shorthorn cattle and two with Peppin Merino sheep from the Abydos region of Western Australia, to study the protein digestibility of various combinations of low-quality roughage and protein-rich concentrates. The relationship between the crude protein and digestible crude protein content of the feed was for cattle : % DCP = 0.832% CP - 1.58 and for sheep : % DCP = 0.865% CP - 2.21 indicating a higher ability to digest protein compared with previous values in the literature for cattle and sheep. It is suggested that the difference may be due to a high degree of adaptation to semi-arid conditions of local sheep and cattle in north-western Australia.

scholarly journals Counts of Atmospheric Freezing Nuclei at Carnarvon, Western Australia, January 1956

1956 ◽  
Vol 9 (4) ◽  
pp. 561 ◽  
Author(s):  
EK Bigg
Keyword(s):  
Indian Ocean ◽  
Western Australia ◽  
New Instrument ◽  
The Indian Ocean ◽  
Nucleus Concentration ◽  
Industrial Sources ◽  
Marine Air

A new instrument for measuring freezing nucleus concentration is described, and an account given of a series of measurements made at Carnarvon in Western Australia during January 1956. The measurements were made on the ground in marine air with a long travel over the Indian Ocean and are thought to be free from contamination by terrestrial dust and smoke from industrial sources.

Hydrogen sulfide intrusion in seagrasses from Shark Bay, Western Australia

2012 ◽  
Vol 63 (11) ◽  
pp. 1027 ◽  
Author(s):  
Marion L. Cambridge ◽  
Matthew W. Fraser ◽  
Marianne Holmer ◽  
John Kuo ◽  
Gary A. Kendrick
Keyword(s):  
Hydrogen Sulfide ◽  
Western Australia ◽  
Cell Walls ◽  
Plant Tissues ◽  
Total Sulfur ◽  
Shark Bay ◽  
Sulfide Toxicity ◽  
Species Specific ◽  
Air Channels ◽  
High Degree

Sulfides in sediments and hydrogen sulfide (H2S) intrusion in plant tissues were investigated for six species of seagrass in Shark Bay, Western Australia, at two sites with elevated salinities of 42 and 45 psu. H2S intrusion ranged from <20% to 100% in roots and rhizomes, indicating a high degree of sulfide intrusion in some cases, although this did not vary consistently between larger, long-lived species and smaller, less persistent species. There were significant differences in accumulation of total sulfur (TS) among species. Anatomy of rhizomes and roots showed species-specific differences in aerenchyma, the air channels that allow oxygen to diffuse down to the roots and sediments, and tissues with thickened cell walls that could present a barrier to diffusion of H2S, suggesting that morphology may influence sulfide intrusion and sulfur accumulation. Sulfide concentrations in seagrass sediments were far lower in Shark Bay than in Florida Bay, a subtropical embayment where sulfide toxicity has been implicated in seagrass dieback. Despite significant H2S intrusion into tissues of some Shark Bay seagrasses, there was no evidence of any deleterious effects in the current conditions.

scholarly journals Szorstkość pokrycia terenu jako źródło błędu metody SfM zastosowanej do rekonstrukcji zasięgu pokrywy śnieżnej = Terrain roughness as a source of error with the SfM method applied to the reconstruction of snow cover extent

2020 ◽  
Vol 92 (3) ◽  
pp. 377-389
Author(s):  
Damian Szafert ◽  
Bartłomiej Miziński ◽  
Tomasz Niedzielski
Keyword(s):  
Snow Cover ◽  
Research Field ◽  
Aerial Imagery ◽  
Dependent Relationship ◽  
Snow Cover Extent ◽  
Sw Poland ◽  
Terrain Roughness ◽  
The One ◽  
High Degree ◽  
Source Of Error

A comparison between errors associated with snow-cover reconstruction performed by processing aerial imagery acquired by a visible-light camera mounted on board unmanned aerial vehicles, one the one hand; and average terrain roughness, on the other, revealed a dependent relationship between these variables. A stronger correlation is noted for two of the studied test areas (Polana Izerska and Krobica, both located in SW Poland), as opposed to the remaining site (Drożyna, SW Poland). In particular, correlations are noticeable where the analysis is performed in moving windows. It is typical for terrain where depth of snow cover is reconstructed with severe errors to reveal a high degree of roughness caused by single trees, clumps of trees or buildings. Ambiguous results are obtained for the Drożyna research field. While the character of the dependent relationship there seems consistent with results for the remaining sites, the strength is low. The lower values for the correlation coefficient were driven by observations for which errors were found to be high while values for the Topographic Ruggedness Index were at the same time low. This effect can be explained by reference to the specific nature of the area reconstructed, which is much transformed by human activity. It proves difficult to reconstruct the depth of snow cover on roads properly, as these are either partially cleared or snow or characterised by its loss in the course of melting. Low thickness of snow cover is thus found to be a constrained when it comes to the generation of accurate reconstructions of the depth of snow cover. This is in fact a finding in agreement with what has been reported by other authors.

scholarly journals Ice phenomena on Lake Czarny Staw pod Rysami

2016 ◽  
Vol 16 (3) ◽  
pp. 165-169 ◽  
Author(s):  
Adam Choiński
Keyword(s):  
Snow Cover ◽  
Ice Cover ◽  
The Mean ◽  
Cover Thickness ◽  
High Degree ◽  
Degree Of Similarity ◽  
Ice Phenomena

Abstract Due to its inaccessibility (in winter), Lake Czarny Staw pod Rysami (Black Lake below Mount Rysy) has no series of continuous observations concerning ice phenomena. For the purpose of supplementing knowledge in this scope, ice corings were performed in the years 2010–2015. They permitted the determination of the variability of ice cover thickness on the lake’s surface. A high degree of similarity was determined in the distribution of ice cover thickness in the analysed winters (in contrast to the nearby Lake Morskie Oko). Moreover, a correlation was determined according to which the thicker the snow cover overlying the ice, the thinner the ice cover. It was determined that the mean thickness of the ice cover of Lake Czarny Staw pod Rysami is higher by approximately a dozen cm than that on Lake Morskie Oko located around 200 m lower.

A cladistic analysis of Banksia (Proteaceae)

1996 ◽  
Vol 9 (5) ◽  
pp. 661 ◽  
Author(s):  
K Thiele ◽  
PY Ladiges
Keyword(s):  
Western Australia ◽  
Cladistic Analysis ◽  
New Combinations ◽  
Infrageneric Classification ◽  
Morphometric Characters ◽  
Initial Analysis ◽  
Cladistic Analyses ◽  
Qualitative Characters ◽  
Anatomical Characters ◽  
High Degree

Banksia is a genus of more than 90 taxa, many of which are common and characteristic in sclerophyll communities in eastern and south-western Australia. Cladistic analyses based on morphological and anatomical characters were used to resolve relationships in the genus. An initial analysis of 35 terminal taxa, including 9 infrageneric taxa assumed to be monophyletic on the basis of one or more synapomorphies, allowed resolution of basal nodes. Subsequent analyses of the putatively monophyletic infrageneric taxa allowed resolution of distal nodes. Some of these lower-level analyses used a mixture of qualitative characters and coded morphometric characters. Together, the analyses afforded a high degree of resolution within the genus, although relationships of some taxa were not well supported. A new infrageneric classification, in which Banksia is divided into 2 subgenera, 12 series and 11 subseries, is proposed. The classification is broadly similar to previously published classifications of the genus, but discards a number of taxa shown to be para- or poly-phyletic. The following new names are published: Banksia series Lindleyanae K.Thiele, series Ochraceae K.Thiele, subseries Leptophyllae K.Thiele, subseries Longistyles K.Thiele, subseries Nutantes K.Thiele, subseries Sphaerocarpae K.Thiele, subseries Cratistyles K.Thiele, subseries Acclives K.Thiele, subseries Integrifoliae K.Thiele, subseries Ericifoliae K.Thiele, subseries Occidentales K.Thiele and subseries Spinulosae K.Thiele. New combinations are provided for Banksia penicillata (A.S.George) K.Thiele, B. brevidentata (A.S.George) K.Thiele, B. hiemalis (A.S.George) K.Thiele and B. dolichostyla (A.S.George) K.Thiele.

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