Population differentiation in Australian Cardamine. III. Variation in germination response

1966 ◽  
Vol 14 (2) ◽  
pp. 189 ◽  
Author(s):  
N Thurling
Keyword(s):  
Genetic Variation ◽  
Low Temperature ◽  
Sea Level ◽  
Seed Dormancy ◽  
Population Differentiation ◽  
Low Temperatures ◽  
New South ◽  
Adaptive Significance ◽  
Germination Response ◽  
South Wales

Genetic variation in germination response was observed among a series of Cardamine populations whose habitats range from sea-level to 7200 ft in southern New South Wales. This variation was closely related to altitude. In populations from below 2000 ft, germination was inhibited at high temperatures, whereas those from above 5500 ft did not germinate at low temperatures. Among populations in which germination was inhibited at low temperatures the intensity of low temperature inhibition increased with increasing altitude. The adaptive significance of high and low temperature seed dormancy in these populations of Cardamine is discussed.

Induction of Reproductive Dormancy in Australian Monarch Butterflies Danaus plexippus (L.)

1983 ◽  
Vol 31 (4) ◽  
pp. 491 ◽  
Author(s):  
DG James
Keyword(s):  
Low Temperature ◽  
Low Temperatures ◽  
Field Experiments ◽  
Ovarian Development ◽  
New South ◽  
Cluster Formation ◽  
Danaus Plexippus ◽  
Long Distance ◽  
South Wales ◽  
Maximum Temperatures

Non-breeding cluster populations of Danaus plexippus (Danaidae) were monitored at five sites in the Sydney area of New South Wales for 5 years. Meteorological records showed that cluster formation was always preceded by periods of cool overcast weather, during which maximum temperatures remained below 18�C for at least 2 days. Field experiments were carried out to test the hypothesis that low post-eclosion temperatures cause reproductive dormancy in Australian D. plexippus. Butterflies were reared in the laboratory and on eclosion exposed to selected temperatures and photophases for 2-4 days before being tagged and released. Recapture data showed that high post-eclosion temperatures (19 or 28�C) inhibited long-distance flight and resulted in ovarian development, but low temperatures (15:6�C, 7:17 h) inhibited ovarian development and permitted long-distance flight. Intermediate temperatures (e.g. 15�C or 12�3�C continuously) gave mixed results. Photoperiod during or before the period of exposure to low temperature did not affect reproduction. The induction, maintenance and termination of reproductive dormancy in Australian D. plexippus are discussed.

Evidence of High Sea Level during Isotope Stage 5c in Queensland, Australia

1985 ◽  
Vol 24 (1) ◽  
pp. 103-114 ◽  
Author(s):  
J. W. Pickett ◽  
C. H. Thompson ◽  
R. A. Kelley ◽  
D. Roman
Keyword(s):  
Sea Level ◽  
New South ◽  
Good Condition ◽  
Coastal Dunes ◽  
Intertidal Sediments ◽  
South Wales ◽  
Eastern Australia ◽  
Maximum Period ◽  
High Dune

Thirty-nine species of scleractinian corals have been recovered from under a high dune on the western (mainland) side of North Stradbroke Island, eastern Australia. The corals are associated with thin intertidal sediments and their good condition implies burial in situ and preservation in a saturated zone. Most likely this occurred as the coast prograded and a large dune advanced into the littoral zone, burying intertidal sediments and coral. The species assemblage indicates a sheltered environment but one open to the ocean without wide fluctuations in salinity. Three species yielded a mean 230Th/234U age of 105,000 yr B.P. which is significantly younger than the nearest Pleistocene corals at Evans Head, New South Wales. The corals provide evidence of a sea stand near present sea level during isotope Stage 5c, which is considerably higher than previously suggested for this period. Their good condition implies that the overlying parabolic dune is of comparable age and formed during that high stand of sea level. Also, the isotope age provides a maximum period for the development of giant podzols in the podzol chronosequences on coastal dunes in southern Queensland.

Broad-toothed rat, Mastacomys fuscus (Rodentia, Muridae), found in alpine heathland in Tasmania.

2001 ◽  
Vol 23 (2) ◽  
pp. 163 ◽  
Author(s):  
MM Driessen
Keyword(s):  
Sea Level ◽  
New South ◽  
Conservation Status ◽  
New South Wales ◽  
The State ◽  
Pine Plantation ◽  
South Wales ◽  
Eucalypt Woodlands ◽  
Sclerophyll Forests

THE broad-toothed rat Mastacomys fuscus is a native, herbivorous rodent that occurs in New South Wales, Victoria and Tasmania. On the Australian mainland the species has been recorded in several habitats at altitudes ranging from sea level to 1800 m. In alpine and sub-alpine areas of New South Wales and Victoria it has been recorded in heathlands, open eucalypt woodlands and wet sedgelands (Calaby and Wimbush 1964; Dixon 1971; Seebeck 1971; Bubela et al. 1991). At lower altitudes in Victoria, it has been recorded in wet sclerophyll forests with a dense undergrowth, coastal heathland, coastal grassland and in a pine plantation (Seebeck 1971; Wallis et al. 1982; Warneke 1960). In Tasmania, M. fuscus has been previously recorded only in buttongrass moorlands of western Tasmania at altitudes ranging from sea level to 900 m (Finlayson 1933; Andrews 1968; Green 1968, 1984; Hocking and Guiler 1983; Driessen and Comfort 1991; Slater 1992; Driessen 1998). Buttongrass moorland (also referred to as sedgeland) is a treeless vegetation typically dominated by Gymnoschoenus sphaerocephalus (buttongrass) that covers more than a million hectares in Tasmania, predominantly in the western part of the State (Jarman et al. 1988). Buttongrass moorland is a very variable vegetation group and not all communities recognised within buttongrass moorland provide habitat for M. fuscus (Driessen and Comfort 1991; Slater 1992; Driessen 1998). The purpose of this note is to report the results of a survey for M. fuscus in alpine heathland, a habitat in which the species has not been previously recorded in Tasmania. This finding has significant implications for the conservation status of this species.

The ecology of Sminthurus viridis (Collembola) III. The influence ofclimate andl land use on its distribution and that of an important predator, Bdellodea lapidaria (Acari : Bdellidae)

1971 ◽  
Vol 19 (2) ◽  
pp. 177 ◽  
Author(s):  
MMH Wallace ◽  
JA Mahon
Keyword(s):  
Land Use ◽  
Low Temperatures ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Growing Season ◽  
Predatory Mite ◽  
South Wales ◽  
Important Predator ◽  
Distribution Limits

The lucerne flea, S. viridis, is restricted to the southern parts of Australia and, apart from a few isolated occurrences in eastern New South Wales, occurs only in areas with an essentially Mediterranean-type climate. The northern inland limit to its distribution agrees closely with the 250-mm isohyet for the growing season of May-October inclusive. The eastern limit to distribution in New South Wales and Victoria agrees with a December-March isohyet of 225 mm. Areas east of this line receive predominantly summer rainfall, and the pastures contain a high proportion of perennial plants which probably do not provide the nutritional stimulus for the development of aestivating diapause eggs in S. viridis essential for oversummering. The predatory mite B. lapidaria requires slightly moister conditions than S. viridis and the limit of its inland distribution agrees reasonably well with the 260-mm isohyet for the May-October period. Low temperatures (mean maximum < 17.5'C) also seem necessary during this period. The eastern distribution limits in Victoria are similar to those of S. viridis.

Production from tagasaste (Chamaecytisus palmensis) at four contrasting sites in New South Wales

1991 ◽  
Vol 31 (5) ◽  
pp. 639 ◽  
Author(s):  
PL Milthorpe ◽  
PR Dann
Keyword(s):  
Low Temperatures ◽  
Dry Matter ◽  
New South ◽  
New South Wales ◽  
Experimental Period ◽  
Production Potential ◽  
Good Production ◽  
South Wales ◽  
Matter Production ◽  
Fodder Crops

In 1985, experiments were conducted at 4 localities in south-eastern and central New South Wales, to assess the production potential of tagasaste. The results were disappointing: 2 experiments failed to establish because of soil waterlogging, while production from the other 2 sites was only intermittent. Annual dry matter production did not exceed 3 t/ha at Condobolin or 5 t/ha at Yass. Although survival of established plants was good, production was limited by prolonged dry periods at Condobolin and by low temperatures during winter at Yass. Tagasaste is costly to establish (up to $A500/ha) and difficult to manage. In our environments, conventional pastures or fodder crops which require simpler management would probably out-produce tagasaste at most times during the experimental period.

Effect of sowing time and nitrogen on rice cultivars of differing growth duration in New South Wales 2. Biomass production and partitioning

1994 ◽  
Vol 34 (7) ◽  
pp. 939
Author(s):  
RF Reinke ◽  
LG Lewin ◽  
RL Williams
Keyword(s):  
Low Temperature ◽  
Short Duration ◽  
New South ◽  
New South Wales ◽  
Biomass Accumulation ◽  
Rice Cultivars ◽  
Growth Duration ◽  
Sowing Time ◽  
South Wales ◽  
Long Duration

In New South Wales, rice cultivars with shorter growth duration are sought to reduce water use and to increase the efficiency of rice production. We examined the biomass accumulation of a short-duration cultivar in comparison with 3 long-duration cultivars across a range of sowing time and nitrogen treatments. The biomass accumulation of the short-duration cultivar was smaller than that of the long-duration cultivars, but the yield potential was similar. This was achieved by the production of similar number of florets per m2, despite smaller biomass at flowering, and greater harvest index. Only early-sown treatments resulted in smaller yield of the short-duration cultivar due to restricted biomass accumulation and floret production. A simple biological model of post-anthesis growth, which included the effect of low temperature, predicted growth with an accuracy similar to that of the measurements. The low temperature function assumed growth stopped following a daily minimum temperature below a specified threshold, and the number of days without growth was a function of the severity of the temperature. We concluded that the yield of short-duration cultivars may be less stable when stress occurs during grain filling because there is less biomass at anthesis and, therefore, less reserve available to fill the grain.

How past sea-level changes can inform future planning: A case study from the Macleay River estuary, New South Wales, Australia

The Holocene ◽  
2014 ◽  
Vol 24 (11) ◽  
pp. 1591-1601 ◽  
Author(s):  
Sarah A McGowan ◽  
Robert GV Baker
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
New South ◽  
New South Wales ◽  
River Estuary ◽  
The Past ◽  
Case Study Area ◽  
South Wales ◽  
The Future

Climate change poses many challenges for the future management and development of the coastal zone. Uncertainties in the rate of future sea-level rise reduce our ability to project potential future impacts. This study seeks to further develop the past–present–future methodology proposed in Baker and McGowan and apply it to an additional case study, the Macleay River estuary, New South Wales (NSW), Australia. The past–present–future methodology uses evidence from the past, the Holocene and Pleistocene, to formulate a response function that can be used to project future sea-level heights. Three scenarios for 2100 were developed to emphasise the uncertainties surrounding future sea levels and the need to consider multiple sea-level rise scenarios when planning for the future: a best case (90 cm rise), mid-case (2.6 m rise) and worst case (5 m rise). Light detection and ranging (LiDAR) data were used to project each of the three scenarios onto the case study area of South West Rocks. The methodology was tested by using shell samples extracted from cores which were AMS dated to determine whether or not Holocene estuarine conditions correlated with the proposed future sea-level rise inundation scenarios. We also conducted an audit of potentially affected infrastructure and land uses, and proposed possible future adaptation strategies for the case study area.

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