Interaction of Fire, Temperature and Light in the Germination Response of 16 Species From the Eucalyptus marginata Forest of South-Western Australia.

1994 ◽  
Vol 42 (5) ◽  
pp. 501 ◽  
Author(s):  
DT Bell
Keyword(s):  
Western Australia ◽  
Light Exposure ◽  
Soil Surface ◽  
Eucalyptus Marginata ◽  
Fire Temperature ◽  
Dark Conditions ◽  
Pre Treatment ◽  
Incubation Temperatures ◽  
Western Australian ◽  
Multiple Conditions

Germination responses to multiple conditions related to fire, temperature and light were examined and interpreted in relation to the environment of the jarrah (Eucalyptus marginata Donn ex Sm.) forest and the mediterranean-type climate of south-western Western Australia. Eight of the 16 selected representatives required a boiling pre-treatment as a simulation of fire before subsequent germination conditions were imposed. Trial conditions included a range of constant incubation temperatures and either a constant dark or 12h light:12h dark illumination cycle. Species common to the understorey tended to have narrow optima to temperature (13-18°C) with the greatest germination being achieved in temperatures typical of winter. Eucalyptus calophylla, one of the canopy species, germinated over a wider range of temperatures than the understorey species tested. Several species (e.g. Acacia pulchella var. glaberrima, Calothamnus rupestris, Eucalyptus marginata, Trymalium ledifolium, Xanthorrhoea gracilis and X. preissii) were not affected by the different light conditions at lower incubation temperatures, but more seeds remained dormant under higher temperatures when exposed to light. Most species, however, germinated best under continuously dark conditions, which related to being buried under soil. Two species, Banksia grandis and Hakea amplexicaulis, showed much higher germination under light exposure conditions compared to continuously dark conditions. These two serotinous species are large seeded and their seed ecology favours large gap and soil surface establishment. The multiple requirements of particular combinations of fire, temperature and light are related to the ecology of these native Western Australian species.

The life history of Trichosurus vulpecula hypoleucus (Phalangeridae) in the jarrah forest of south-western Australia

2005 ◽  
Vol 53 (4) ◽  
pp. 265 ◽  
Author(s):  
A. F. Wayne ◽  
C. G. Ward ◽  
J. F. Rooney ◽  
C. V. Vellios ◽  
D. B. Lindenmayer
Keyword(s):  
Life History ◽  
Western Australia ◽  
The Body ◽  
Summer Drought ◽  
Testis Size ◽  
Trichosurus Vulpecula ◽  
Adult Males ◽  
Eucalyptus Marginata ◽  
Adult Females ◽  
Western Australian

The common brushtail possum (Trichosurus vulpecula) is noted for its morphological, biological and ecological variability across its range. Despite having suffered substantial population declines since European settlement, relatively little has been published on the south-western Australian subspecies, the koomal (T. v. hypoleucus). This study reports morphological, reproductive and general life-history data from an 18-month study of a population in the southern jarrah (Eucalyptus marginata) forest at Chariup (part of Perup), near Manjimup, in south-western Australia. As one of the smallest subspecies, adult males of T. v. hypoleucus averaged 1616 g and females averaged 1470 g. Sexual dimorphism also occurred with head length and pes length, but not tail length. A single autumn breeding season occurred in both 2002 and 2003, in which all adult females bred and produced a single young between February and May. The onset of autumn births was associated with the end of the summer drought. Unlike many other Trichosurus populations, no spring breeding pulse or ‘double-breeding’ events were observed. At least 83% of pouch young survived to pouch emergence. The growth rate of offspring was initially linear, but became curvilinear and approached an asymptote after ~5 months. Most females bred for the first time when they were 1 year old. On the basis of testis size, males also matured at 1 year old. The body condition of adult males, but not adult females, changed significantly over time and followed an apparently seasonal pattern in which their condition was poorest in winter and best in summer. While many of the life-history traits of the Chariup population were similar to those of other south-western Australian populations of T. v. hypoleucus, the most striking variations included age at maturity, extent of spring breeding pulse and female fecundity. Further comparisons with conspecifics elsewhere in Australia and New Zealand also highlight the variability exhibited by T. vulpecula across its range. Some aspects of the biology of T. v. hypoleucus were particularly similar to those observed for T. v. arnhemensis in northern Australia.

Flowering in darkness: a new species of subterranean orchid Rhizanthella (Orchidaceae; Orchidoideae; Diurideae) from Western Australia

Phytotaxa ◽  
2018 ◽  
Vol 334 (1) ◽  
pp. 75 ◽  
Author(s):  
KINGSLEY W. DIXON ◽  
MAARTEN J. M. CHRISTENHUSZ
Keyword(s):  
Western Australia ◽  
Soil Surface ◽  
Single Species ◽  
Flowering Plants ◽  
Disjunct Distribution ◽  
New Taxon ◽  
Australian Species ◽  
Western Australian ◽  
A New Species ◽  
Eastern Seaboard

Few plants are so cryptic as the underground orchids, Rhizanthella Rogers (1928: 1), of Australia. Unlike the species on the eastern seaboard of Australia, the Western Australian species spend their entire life cycle, including flowering, below the soil surface (only rarely with the tips of the bracts showing), making them unique among orchids and indeed, among flowering plants generally (Brown et al. 2013). Discovery in 1928 of the first underground orchid in Western Australia was an international sensation where the plant was described as ‘a remarkable subterranean orchid’ (Wilson 1929). The new taxon described in this paper resolves the enigmatic, disjunct distribution of Rhizanthella in Western Australia, where there was thought to be a central and southern node of a single species, R. gardneri Rogers (1928: 1).

The breeding biology of the Forest Red-tailed Black Cockatoo Calyptorhynchus banksii naso Gould in south-western Australia. II. Breeding behaviour and diet

2013 ◽  
Vol 19 (2) ◽  
pp. 143 ◽  
Author(s):  
R E Johnstone ◽  
T Kirby ◽  
K Sarti
Keyword(s):  
Western Australia ◽  
Wildlife Conservation ◽  
Breeding Biology ◽  
Melia Azedarach ◽  
Eucalyptus Marginata ◽  
Breeding Behaviour ◽  
Short Period ◽  
Fledgling Success ◽  
Western Australian ◽  
Courtship Displays

Little is known of the breeding behaviour of the Forest Red-tailed Black Cockatoo Calyptorhynchus banksii naso (FRTBC), a large, iconic forest cockatoo, endemic to the south-west corner of Western Australia, currently listed as Vulnerable under the State Western Australian Wildlife Conservation Act and under the Commonwealth Environment Protection and Biodiversity Conservation Act. In this paper, we provide details of breeding behaviour of FRTBC based on observations throughout the year over 17 years, together with observations of diet and feeding behaviour over the same period. FRTBC are monogamous hollow-nesters. Breeding was recorded in all months, with peaks in autumn-winter (April– June) and spring (August–October), with few records in January and February. Breeding also varied between years, with little breeding in 1999, 2001 and 2008, but many observations in 2006 and 2009. Breeding occurred at times of fruiting of either of the principal feed trees, Jarrah Eucalyptus marginata or Marri Corymbia calophylla, so it does not depend solely on one or the other of these species. Courtship displays were noted at all times of the day, from before dawn at roost sites to dusk. In total, 205 breeding events were recorded, of which 69 (93%) of 72 nests had breeding confirmed on a second visit. Use of particular nest hollows varied considerably, with some used only once and some up to seven times. Only one egg is laid, which the female incubates for 29 to 31 days, before a nestling hatches weighing between 27 and 32 g. The female remains in the hollow during incubation and only leaves for a short period in the evening to be fed by the male, usually at dusk. The chicks are brooded for up to 10 days, after which the female leaves the nest between dawn and dusk. Pairs of birds appear to recognise each other by calls, not responding to calls by others in the area. Chicks only respond when the parent is heard. Chicks are fully feathered at 48 days. Fledgling success was estimated at 60%. Juveniles remain dependent on the adults 18 months to 2 years. Thirty-seven chicks were banded between 1997 and 2011. Juvenile-immature birds moved on average less than 3 km from their natal tree and older birds were observed moving up to 19 km. This suggests that FRTBC are generally sedentary. Immature birds took up to three times as long as their parents to open Jarrah or Marri nuts and eat the seeds. In recent years there has been an interesting change in foraging behaviour of birds in the northern Darling Range (adjacent to the Perth metropolitan area) with the FRTBC discovering and using a new food source, the introduced Cape Lilac Melia azedarach, and this species is of growing importance as food in the Perth region. In combination, the data on breeding biology and diet highlight the importance of identifying recruitment rates and food availability in managing populations of FRTBC.

Factors that contribute to urban–rural gradients in risk of schizophrenia: Comparing Danish and Western Australian registers

2021 ◽  
pp. 000486742110096
Author(s):  
Oleguer Plana-Ripoll ◽  
Patsy Di Prinzio ◽  
John J McGrath ◽  
Preben B Mortensen ◽  
Vera A Morgan
Keyword(s):  
Confidence Interval ◽  
Western Australia ◽  
Urban Areas ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Hazard Ratio ◽  
Indigenous Status ◽  
Increased Risk ◽  
The Relationship ◽  
Western Australian

Introduction: An association between schizophrenia and urbanicity has long been observed, with studies in many countries, including several from Denmark, reporting that individuals born/raised in densely populated urban settings have an increased risk of developing schizophrenia compared to those born/raised in rural settings. However, these findings have not been replicated in all studies. In particular, a Western Australian study showed a gradient in the opposite direction which disappeared after adjustment for covariates. Given the different findings for Denmark and Western Australia, our aim was to investigate the relationship between schizophrenia and urbanicity in these two regions to determine which factors may be influencing the relationship. Methods: We used population-based cohorts of children born alive between 1980 and 2001 in Western Australia ( N = 428,784) and Denmark ( N = 1,357,874). Children were categorised according to the level of urbanicity of their mother’s residence at time of birth and followed-up through to 30 June 2015. Linkage to State-based registers provided information on schizophrenia diagnosis and a range of covariates. Rates of being diagnosed with schizophrenia for each category of urbanicity were estimated using Cox proportional hazards models adjusted for covariates. Results: During follow-up, 1618 (0.4%) children in Western Australia and 11,875 (0.9%) children in Denmark were diagnosed with schizophrenia. In Western Australia, those born in the most remote areas did not experience lower rates of schizophrenia than those born in the most urban areas (hazard ratio = 1.02 [95% confidence interval: 0.81, 1.29]), unlike their Danish counterparts (hazard ratio = 0.62 [95% confidence interval: 0.58, 0.66]). However, when the Western Australian cohort was restricted to children of non-Aboriginal Indigenous status, results were consistent with Danish findings (hazard ratio = 0.46 [95% confidence interval: 0.29, 0.72]). Discussion: Our study highlights the potential for disadvantaged subgroups to mask the contribution of urban-related risk factors to risk of schizophrenia and the importance of stratified analysis in such cases.

Phytotoxic Effect of Decaying Quackgrass (Agropyron repens) Residues

Weed Science ◽  
1979 ◽  
Vol 27 (6) ◽  
pp. 595-598 ◽  
Author(s):  
T. V. Toai ◽  
D. L. Linscott
Keyword(s):  
Incubation Temperature ◽  
Soil Surface ◽  
Water Soluble ◽  
Water Extracts ◽  
Phytotoxic Activity ◽  
Phytotoxic Effect ◽  
Effects Of Temperature ◽  
Incubation Temperatures ◽  
Toxin Formation ◽  
Agropyron Repens

We studied the effects of temperature (5, 10, 20, and 30 C) on the phytotoxic activity of decaying quackgrass [Agropyron repens (L.) Beauv.] leaves and rhizomes that were incubated in soils for 0, 1, 2, 4, and 6 weeks. Alfalfa (Medicago sativa L.) seeds were grown for 96 h in water, water extracts of control soils, and water extracts of soil with quackgrass rhizomes or leaves. Dried quackgrass rhizomes and leaves contained water-soluble toxins that inhibited alfalfa seedling development and growth. There was a strong interaction between incubation time and temperature on the development of additional toxins by decomposing quackgrass. High incubation temperature (30 C) accelerated toxin formation and ultimate decay. Intermediate temperature (20 C) delayed toxin formation and decay. Low incubation temperatures (5 C and 10 C) prevented formation of additional toxin. In all extracts of quackgrass and soil that had been incubated for 6 weeks, normal alfalfa seedling number equaled that in water. However, seedling growth varied with incubation temperatures.Treatment of quackgrass with glyphosate [N-(phosphonomethyl) glycine] in the greenhouse did not influence the toxicity of decaying quackgrass leaves. The highest toxic effect was noted after 1 week of decay on the soil surface.

scholarly journals Effect of noisy galvanic vestibular stimulation on dynamic posture sway under visual deprivation in patients with bilateral vestibular hypofunction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Po-Yin Chen ◽  
Ying-Chun Jheng ◽  
Chien-Chih Wang ◽  
Shih-En Huang ◽  
Ting-Hua Yang ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Light Exposure ◽  
Light Condition ◽  
Vestibular Stimulation ◽  
Galvanic Vestibular Stimulation ◽  
Lateral Deviation ◽  
Clinical Trial Registration ◽  
Vestibular Hypofunction ◽  
Dark Conditions ◽  
Bilateral Vestibular Hypofunction

AbstractA single-blind study to investigate the effects of noisy galvanic vestibular stimulation (nGVS) in straight walking and 2 Hz head yaw walking for healthy and bilateral vestibular hypofunction (BVH) participants in light and dark conditions. The optimal stimulation intensity for each participant was determined by calculating standing stability on a force plate while randomly applying six graded nGVS intensities (0–1000 µA). The chest–pelvic (C/P) ratio and lateral deviation of the center of mass (COM) were measured by motion capture during straight and 2 Hz head yaw walking in light and dark conditions. Participants were blinded to nGVS served randomly and imperceivably. Ten BVH patients and 16 healthy participants completed all trials. In the light condition, the COM lateral deviation significantly decreased only in straight walking (p = 0.037) with nGVS for the BVH. In the dark condition, both healthy (p = 0.026) and BVH (p = 0.017) exhibited decreased lateral deviation during nGVS. The C/P ratio decreased significantly in BVH for 2 Hz head yaw walking with nGVS (p = 0.005) in light conditions. This study demonstrated that nGVS effectively reduced walking deviations, especially in visual deprived condition for the BVH. Applying nGVS with different head rotation frequencies and light exposure levels may accelerate the rehabilitation process for patients with BVH.Clinical Trial Registration This clinical trial was prospectively registered at www.clinicaltrials.gov with the Unique identifier: NCT03554941. Date of registration: (13/06/2018).

Tree Species Preferences of Foraging Birds in Jarrah Forest in Western Australia.

1985 ◽  
Vol 12 (3) ◽  
pp. 461 ◽  
Author(s):  
I Abbott ◽  
PV Heurck
Keyword(s):  
Western Australia ◽  
Tree Species ◽  
Bird Species ◽  
Selective Logging ◽  
Jarrah Forest ◽  
Eucalyptus Marginata ◽  
Silvicultural Treatments ◽  
Species Preferences

A study of foraging by 10 bird species suggests that selective logging of large Eucalyptus marginata will only have affected Melithreptus lunatus, but that proposed silvicultural treatments, including removal of Banksia grandis, may affect several other bird species.

Life cycle of the western school prawn, Metapenaeus dalli Racek, in a Western Australian estuary

1986 ◽  
Vol 37 (1) ◽  
pp. 95 ◽  
Author(s):  
IC Potter ◽  
JW Penn ◽  
KS Brooker
Keyword(s):  
Life Cycle ◽  
Western Australia ◽  
Sexual Maturity ◽  
Second Year Of Life ◽  
Second Year ◽  
Australian Estuary ◽  
Western Australian

The absence of marine records for M. dalli below latitude 31�S., together with data on gonadal stages and spermatophore deposition on females of this species in the Swan estuary, provide very strong indications that the western school prawn typically breeds in estuarine environments in south-western Australia. The 0 + recruits, which first appeared in samples in February, remained in the estuary during the following months and by November had reached a size suitable for exploitation. At this time they were approaching sexual maturity and were starting to move from the shallows to the deeper waters of the estuary where they remained for their second year of life. In contrast to Australian Penaeus species, M. dalli mates during the intermoult period when the shell is hard rather than immediately after moulting.

Aspects of reproduction, and morphology of the penis, of Pseudantechinus woolleyae (Marsupialia : Dasyuridae)

2017 ◽  
Vol 65 (6) ◽  
pp. 357 ◽  
Author(s):  
P. A. Woolley
Keyword(s):  
Western Australia ◽  
Arid Regions ◽  
Wide Distribution ◽  
Erectile Tissue ◽  
Australian Museum ◽  
Seasonal Breeder ◽  
Males And Females ◽  
One Year ◽  
Western Australian

Woolley’s Pseudantechinus, P. woolleyae, has remained virtually unstudied in the 30 years since its recognition in 1988 as a species distinct from P. macdonnellensis. It has a wide distribution in arid regions of Western Australia. What little is known of its biology comes largely from studies carried out over the years 1988–91 on one wild-caught female and her offspring, and a few specimens held in the collection of the Western Australian Museum. P. woolleyae is a seasonal breeder and young are born from late July to early October. They mature when ~7 months old. Both males and females are potentially capable of breeding in more than one year. Males have accessory erectile tissue that does not form an appendage on the penis.

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