Key Periods in the Evolution of the Cenozoic Vegetation and Flora in Western Tasmania: the Late Pliocene

1995 ◽  
Vol 43 (5) ◽  
pp. 505 ◽  
Author(s):  
MK MacPhail ◽  
EA Colhoun ◽  
SJ Fitzsimons
Keyword(s):  
Plant Communities ◽  
East Coast ◽  
Published Data ◽  
Pleistocene Glaciation ◽  
Forest Types ◽  
Late Pliocene ◽  
Relict Populations ◽  
Pollen And Spores ◽  
Lagarostrobos Franklinii ◽  
Warm Temperate

Fossil pollen and spores in organic-rich sediments in a side gully in the Linda Valley, western Tasmania, preserve one of the most detailed records of a Late Pliocene flora and vegetation available to date in Australia. This includes Araucariaceae, Beauprea Brongn. & Gris. and a number of sub-canopy broadleaf trees now confined to warm temperate-tropical habitats. Changes in community dominance are interpreted in terms of alluvial events and point to the existence of altitudinally zoned plant communities in western Tasmania-Microstrobos J. Garden & L. Johnson heathland on the higher slopes and Nothofagus (Brassospora) Hill & Read-Lagarostrobos franklinii (J.D.Hook.) Quinn evergreen rainforest with or without Dacrydium Sol. ex Lamb. emmend. de Laub. at lower elevations. The evidence demonstrates the survival of Nothofagus (Brassospora) spp in western Tasmania at a time when other published data imply the taxon was virtually eliminated from the south-eastern mainland. It is proposed that increasingly seasonal climates drove an 'ecological wedge' into a former continuum of wet forest types along the east coast of Australia, with Plio-Pleistocene glaciation being ultimately responsible for the demise, of what had become relict populations, of Brassospora spp. in western Tasmania.

A Fossil Flora From Rafted Plio-Pleistocene Mudstones at Regatta Point, Tasmania.

1985 ◽  
Vol 33 (5) ◽  
pp. 497 ◽  
Author(s):  
RS Hill ◽  
MK MacPhail
Keyword(s):  
Early Pleistocene ◽  
Fossil Flora ◽  
The West ◽  
Late Pliocene ◽  
Late Tertiary ◽  
Cool Temperate ◽  
Successful Establishment ◽  
Pollen And Spores ◽  
The Common ◽  
Lagarostrobos Franklinii

A Late Pliocene-Early Pleistocene flora from Regatta Point on Macquarie Harbour contains pollen, cladodes, flowers and infructescences of Casuarina (s.l.), suggesting that the site of deposition was surrounded by the source plants. However, leaves and shoots of Nothofagus cunninghamii, Eucryphia, Atherosperma moschatum, Quintinia, Acacia, Lagarostrobos franklinii, Phyllocladus aspleniifolius, Podocarpus, Athrotaxis selaginoides and A. cf. cupressoides also occur, along with pollen and spores of the common rainforest species, and it can be inferred that a cool temperate rainforest was present upstream of the site of deposition. This fossil flora represents the earliest evidence to date of modern rainforest elements in Tasmania. Pollen of a number of modern sclerophyll species, including Epacridaceae, Proteaceae and Eucalyptus, is also present. The presence of a Quintinia leaf in the Regatta Point flora is evidence that some species have become extinct in Tasmania relatively recently. Extant Tasmanian rainforests evolved from more diverse Mid Tertiary rainforests, probably in response to the Late Tertiary cooling and repeated Quaternary glaciations. The same environmental vicissitudes may have also been responsible for the successful establishment of eucalypts on the west coast of Tasmania by the Late Pliocene-Early Pleistocene, resulting in a vegetation probably similar to that now present around Macquarie Harbour.

scholarly journals Marine Heatwaves Exceed Cardiac Thermal Limits of Adult Sparid Fish (Diplodus capensis, Smith 1884)

2021 ◽  
Vol 8 ◽  
Author(s):  
Kerry-Ann van der Walt ◽  
Warren M. Potts ◽  
Francesca Porri ◽  
Alexander C. Winkler ◽  
Murray I. Duncan ◽  
...  
Keyword(s):  
Heart Rate ◽  
East Coast ◽  
Reaction Rates ◽  
Range Limit ◽  
Thermal Indices ◽  
Thermal Thresholds ◽  
Thermal Limits ◽  
Relative Change ◽  
Warm Temperate ◽  
Established Technique

Climate change not only drives increases in global mean ocean temperatures, but also in the intensity and duration of marine heatwaves (MHWs), with potentially deleterious effects on local fishes. A first step to assess the vulnerability of fishes to MHWs is to quantify their upper thermal thresholds and contrast these limits against current and future ocean temperatures during such heating events. Heart failure is considered a primary mechanism governing the upper thermal limits of fishes and begins to occur at temperatures where heart rate fails to keep pace with thermal dependency of reaction rates. This point is identified by estimating the Arrhenius breakpoint temperature (TAB), which is the temperature where maximum heart rate (fHmax) first deviates from its exponential increase with temperature and the incremental Q10 breakpoint temperature (TQB), which is where the Q10 temperature coefficient (relative change in heart rate for a 10°C increase in temperature) for fHmax abruptly decreases during acute warming. Here we determined TAB, TQB and the temperature that causes cardiac arrhythmia (TARR) in adults of the marine sparid, Diplodus capensis, using an established technique. Using these thermal indices results, we further estimated adult D. capensis vulnerability to contemporary MHWs and increases in ocean temperatures along the warm-temperate south-east coast of South Africa. For the established technique, we stimulated fHmax with atropine and isoproterenol and used internal heart rate loggers to measure fHmax under conditions of acute warming in the laboratory. We estimated average TAB, TQB, and TARR values of 20.8°C, 21.0°C, and 28.3°C. These findings indicate that the physiology of D. capensis will be progressively compromised when temperatures exceed 21.0°C up to a thermal end-point of 28.3°C. Recent MHWs along the warm-temperate south-east coast, furthermore, are already occurring within the TARR threshold (26.6–30.0°C) for cardiac function in adult D. capensis, suggesting that this species may already be physiologically compromised by MHWs. Predicted increases in mean ocean temperatures of a conservative 2.0°C, may further result in adult D. capensis experiencing more frequent MHWs as well as a contraction of the northern range limit of this species as mean summer temperatures exceed the average TARR of 28.3°C.

Cyclacanthia n.g. (Demospongiae: Poecilosclerida: Latrunculiidae incertea sedis), a new genus of marine sponges from South African waters, and description of two new species

Zootaxa ◽  
2004 ◽  
Vol 725 (1) ◽  
pp. 1 ◽  
Author(s):  
TOUFIEK SAMAAI ◽  
VASHA GOVENDER ◽  
MICHELLE KELLY
Keyword(s):  
South African ◽  
Type Species ◽  
New Genus ◽  
East Coast ◽  
Hot Spot ◽  
Marine Sponges ◽  
The Family ◽  
Two New Species ◽  
Shallow Subtidal ◽  
Warm Temperate

The new genus Cyclacanthia n.g. is erected in the poecilosclerid Family Latrunculiidae for the type species Latrunculia bellae Samaai & Kelly, 2003, and two further species, Cyclacanthia cloverlyae sp. nov., and Cyclacanthia mzimayiensis sp. nov.. The latter species are from the subtropical east coast of South Africa, whereas C. bellae has only been found further south in warm temperate Algoa Bay. Cyclacanthia n.g. differs from other Latrunculiidae genera in the ontogeny, morphology and structure of the mature microsclere, the isospinodiscorhabd, which has only three major whorls of projections as opposed to the four in species of Latrunculia du Bocage. Additional diagnostic characters include the presence of broad swathes of megascleres that diverge from the base of the sponge towards the upper choanosome, where they form loose brushes and the typical whispy reticulation of most Latrunculiidae. The ectosome is composed of a dense tangential layer of megascleres, an irregular palisade of microscleres at the surface, and a permanently encrusting habit. Cyclacanthia n.g. is the second new latrunculid genus recently described from shallow subtidal South African waters, following major revision of the family. The presence of species in four of the five known genera in the family, on South African coastlines, suggests a diversity hot-spot for the family in this region.

scholarly journals Distribution and Ecology of Clathrus archeri in Romania

2014 ◽  
Vol 6 (3) ◽  
pp. 288-291
Author(s):  
Cipran BÎRSAN ◽  
Ana COJOCARIU ◽  
Elena CENUŞĂ
Keyword(s):  
Plant Communities ◽  
Environmental Conditions ◽  
Rare Species ◽  
Western Europe ◽  
Habitat Type ◽  
Published Data ◽  
Hay Meadows ◽  
Eastern Carpathians ◽  
Distribution And Ecology

Although Clathrus archeri is a widely spread species in the Western Europe, in Romania it is considered a rare species, identified from only eight sites. In July 2013, it was found in two new sites from Gurghiu and Bârgău Mountains, in the Romanian Eastern Carpathians. This paper presents a detailed description of the new recorded specimens and of the habitat where this fungus was found. Plant communities where Clathrus archeri was recorded belong to the “mountain hay meadows” habitat type (Festuco rubrae - Agrostietum capillaris community). Taking into consideration the previous published data, the comparison with other habitats types in which this species occurs suggests that Clathrus archeri has no special preferences for certain environmental conditions.

Taxonomic Review of the perciform fish genus Acanthistius from the east coast of southern Africa, with description of a new species and designation of a neotype for Serranus sebastoides Castelnau, 1861

Zootaxa ◽  
2010 ◽  
Vol 2352 (1) ◽  
pp. 59 ◽  
Author(s):  
PHILLIP C. HEEMSTRA
Keyword(s):  
South Africa ◽  
New Species ◽  
South America ◽  
Southern Africa ◽  
East Coast ◽  
Valid Species ◽  
Shallow Waters ◽  
Single Specimen ◽  
Warm Temperate ◽  
A New Species

The genus Acanthistius Gill, 1862 comprises ten putative valid species occurring in shallow warm-temperate waters of the Southern Hemisphere: South America (coasts of Ecuador, Peru, Chile, Brazil, and Argentina) southern Africa (Namibia and South Africa), southern Australia, New Zealand, Lord Howe, Norfolk, Kermadec and Easter, and Sala y Gómez islands. Two species: Acanthistius sebastoides (Castelnau, 1861) and Acanthistius sp are known from shallow waters of the east coast of South Africa (Heemstra and Randall, 1986). The latter taxon, previously known from a brief description of a single specimen, is here described from 23 specimens and named Acanthistius joanae. Acanthistius sebastoides is redescribed from 13 specimens and compared with A. joanae and species of Acanthistius known from South America and Australia. A neotype is designated for Serranus sebastoides Castelnau, 1861, as the two syntypes are apparently lost.

Marine mammals and Japanese long-line fishing vessels in Australian waters: operational interactions and sightings

2006 ◽  
Vol 12 (1) ◽  
pp. 31 ◽  
Author(s):  
Catherine Bell ◽  
Peter Shaughnessy ◽  
Margie Morrice ◽  
Bob Stanley
Keyword(s):  
Marine Mammal ◽  
Marine Mammals ◽  
East Coast ◽  
Fishing Gear ◽  
Killer Whales ◽  
Fishing Vessels ◽  
Long Line ◽  
Target Fish ◽  
Pilot Whales ◽  
Warm Temperate

Observers from the Australian Fisheries Management Authority worked on randomly chosen Japanese long-line vessels in the Australian Fishing Zone (AFZ) between 1980 and 1997. Observer reports (n = 451) were inspected for interactions or sightings of marine mammals. An operational interaction was defined as an activity or behaviour that involved direct contact between a marine mammal and fishing gear, bait, target fish or bycatch, or indications that the marine mammal was feeding. A sighting was defined as the recording of marine mammals that passed the vessel without changing course and/or did not appear to interact with the vessel or its gear. Observers witnessed 23 interactions and made another 44 sightings of marine mammals. A further 24 interactions and sightings were relayed by crew members. Killer whales were reported most frequently: most incidences of fish being damaged, taken or frightened away were attributed to them. Eleven marine mammals were caught: two died, seven were released, and the fate of two others was not recorded. Between 1991 and 1996, when observer coverage was 11.5% overall in the AFZ, the incidence of interactions was 1.71 per million hooks set. The estimated number of interactions in that seven-year period was 157 in the AFZ. Since 1997, the long-line fishery has been conducted by Australian vessels, primarily off the east coast of mainland Australia in warm-temperate waters. A higher proportion of interactions can be expected with killer whales and short-finned pilot whales in these waters, and fewer with seals.

Studies on structure in plant communities. VI. The significance of pattern evaluation in some Australian dry-land vegetation types

1969 ◽  
Vol 17 (2) ◽  
pp. 315 ◽  
Author(s):  
DJ Anderson ◽  
SWL Jacobs ◽  
AR Malik
Keyword(s):  
Plant Communities ◽  
Low Density ◽  
Vegetation Types ◽  
Dry Land ◽  
Density Data ◽  
Simple Observation ◽  
Relict Populations ◽  
Differential Elimination

The analysis of density data from a variety of Australian dry-land vegetation types provides evidence of widespread randomness when the component distributions are compared with a Poissonian model. While such randomness may be reflecting traditionally held beliefs concerning structure in colonizing and "relict" populations, randomness may develop as a result of a differential elimination of individuals between high and low density phases in an originally patterned population. It is suggested that structure in vegetation cannot be estimated reliably by simple observation alone, and this statement is evidenced by the ubiquity of random (and to a lesser extent contagious) distributions which are found in Australian dry-land communities, in contradistinction to the widely held view that such distributions are necessarily essentially regular in their character.

scholarly journals Spatial Variation in the Marine Radiocarbon Reservoir Effect Throughout the Scottish Post-Roman to Late Medieval Period: North Sea Values (500–1350 BP)

Radiocarbon ◽  
2010 ◽  
Vol 52 (3) ◽  
pp. 1166-1181 ◽  
Author(s):  
N Russell ◽  
G T Cook ◽  
P L Ascough ◽  
A J Dugmore
Keyword(s):  
North Sea ◽  
East Coast ◽  
Published Data ◽  
Estuarine System ◽  
Data Set ◽  
Reservoir Effect ◽  
Global Average ◽  
The North ◽  
Late Medieval Period ◽  
Water Composition

The marine radiocarbon reservoir effect (MRE) occurs as a spatially and temporally dependent variable owing to localized changes in oceanic water composition. This study investigates ΔR values (deviations from the global average MRE whose ΔR = 0) during the period 500–1350 BP for the east coast of Scotland, where a complex estuarine system exists that drains into the semi-enclosed North Sea basin. Due to the availability of suitable archaeological samples, the data set has a distinct Medieval focus that spans the area from Aberdeen in the north to East Lothian in the south. Many of the ΔR values are not significantly different from 0 (the global average), but there are occasional excursions to negative values (max –172 ± 20) indicating the presence of younger water. These values show greater variability compared to other published data for this general region, suggesting that considerable care must be taken when dating marine derived samples from archaeological sites on the east coast of Scotland.

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