scholarly journals Plants, position and pollination: Planting arrangement and pollination limitation in a revegetated eucalypt woodland

2019 ◽  
Vol 20 (3) ◽  
pp. 222-230 ◽  
Author(s):  
Kimberly P. McCallum ◽  
Martin F. Breed ◽  
Andrew J. Lowe ◽  
David C. Paton
Keyword(s):  
Pollination Limitation ◽  
Eucalypt Woodland

scholarly journals Concurrent Measurements of Soil and Ecosystem Respiration in a Mature Eucalypt Woodland: Advantages, Lessons, and Questions

2021 ◽  
Vol 126 (3) ◽  
Author(s):  
A. A. Renchon ◽  
J. E. Drake ◽  
C. A. Macdonald ◽  
D. Sihi ◽  
N. Hinko‐Najera ◽  
...  
Keyword(s):  
Ecosystem Respiration ◽  
Eucalypt Woodland

Vegetation History and Water Fluctuations at Lake Leake, South-Eastern South Australia. II. 50 000 B.P. To 10 000 B.P

1975 ◽  
Vol 23 (5) ◽  
pp. 815 ◽  
Author(s):  
JR Dodson
Keyword(s):  
Vegetation History ◽  
South Australia ◽  
Annual Rainfall ◽  
Drill Core ◽  
Radiocarbon Dates ◽  
Last Glaciation ◽  
Annual Minimum Temperature ◽  
Average Annual Rainfall ◽  
Eucalypt Woodland ◽  
Open Woodland

A drill core from Lake Leake contains a sedimentary sequence extending from about 50,000 B.P. until the present. This paper discusses the results of the pollen analyses and six radiocarbon dates which span the period from about 50,000 until about 10,000 B.P. There are core sections which yielded low numbers of pollen and thus there are gaps in the vegetation record. It is suggested that open eucalypt woodland was replaced by eucalypt woodland with heath at about 50,000 B.P. and remained until about 39,000 B.P. Open woodland then returned but was replaced by eucalypt woodland with heath by 38,000 B.P. Some time after 35,000 B.P., open eucalypt woodland conditions returned and persisted until near 10,000 B.P. when Casuarina stricta migrated into the area. Through- out the period in question the climate was drier than it has been in the last 10,000 radiocarbon years. There were wet periods about 50,000 and 39,000 B.P. and from 38,000 to 35,000 B.P. The character of the sediments and the relative amounts of pollen preserved suggest that conditions were relatively dry from 50,000 to 39,000 B.P. and from after 35,000 until near 10,000 B.P. The lake was driest during the period of the last glaciation but the presence of eucalypt pollen is interpreted as indicating that the average annual minimum temperature was above 10�C and the average annual rainfall was above 20-25 cm.

The Biology of the Gecko Oedura reticulata Bustard, in a Smal Habitat Isolate in the Western Australian Wheatbelt

1983 ◽  
Vol 10 (3) ◽  
pp. 543 ◽  
Author(s):  
RA How ◽  
DJ Kitchner
Keyword(s):  
Dead Wood ◽  
Life History Strategy ◽  
Late Summer ◽  
Native Vegetation ◽  
Body Temperatures ◽  
Ambient Temperatures ◽  
Slight Excess ◽  
Definable Groups ◽  
Eucalypt Woodland ◽  
Western Australian

The arboreal gecko Oedura reticulata was studied in an isolated 1-ha eucalypt woodland in the Western Australian wheatbelt. Females reach maturity in their 4th year and lay two eggs between October and January. Males reach maturity in their 3rd year, their testes are largest between July and October. Young hatch in mid to late summer but immature individuals are infrequently captured during their first 18 months. Individuals live more than 6 years. Population size ranged between 91 and 119 individuals. Individuals were placed into eight definable groups. There was a slight excess of males in each cohort. Activity, which is greatest in summer and least in winter, is closely correlated with ambient temperature. Body temperatures become noticeably higher than ambient temperatures between 23�C and 16�C; below 16�C activity is greatly reduced. The higher numbers of O.reticulata occur on mature smooth-barked eucalypt trees that have both large areas of foliage and dead wood. Only immature individuals frequently occupy rough-barked eucalypts. Their life-history strategy is considered in respect of small, isolated and disturbed remnants of native vegetation.

scholarly journals Flowering phenology, fruiting success and progressive deterioration of pollination in an early-flowering geophyte

2010 ◽  
Vol 365 (1555) ◽  
pp. 3187-3199 ◽  
Author(s):  
James D. Thomson
Keyword(s):  
Fruit Set ◽  
Flowering Phenology ◽  
Bumble Bee ◽  
Late Flowering ◽  
Progressive Deterioration ◽  
Pollination Limitation ◽  
Hand Pollination ◽  
Western Colorado ◽  
Spatio Temporal ◽  
Erythronium Grandiflorum

Spatio-temporal patterns of snowmelt and flowering times affect fruiting success in Erythronium grandiflorum Pursh (Liliaceae) in subalpine western Colorado, USA. From 1990 to 1995, I measured the consistency across years of snowmelt patterns and flowering times along a permanent transect. In most years since 1993, I have monitored fruit set in temporal cohorts (early- to late-flowering groups of plants) at one site. To assess ‘pollination limitation’, I have also conducted supplemental hand-pollination experiments at various times through the blooming season. The onset of blooming is determined by snowmelt, with the earliest years starting a month before the latest years owing to variation in winter snowpack accumulation. Fruit set is diminished or prevented entirely by killing frosts in some years, most frequently but not exclusively for the earlier cohorts. When frosts do not limit fruit set, pollination limitation is frequent, especially in the earlier cohorts. Pollination limitation is strongest for middle cohorts: it tends to be negated by frost in early cohorts and ameliorated by continuing emergence of bumble-bee queens in later cohorts. This lily appears to be poorly synchronized with its pollinators. Across the years of the study, pollination limitation appears to be increasing, perhaps because the synchronization is getting worse.

scholarly journals Wind pollination and propagule formation in Rhizophora mangle L. (Rhizophoraceae): resource or pollination limitation?

2014 ◽  
Vol 86 (1) ◽  
pp. 229-238 ◽  
Author(s):  
TARCILA L. NADIA ◽  
ISABEL C. MACHADO
Keyword(s):  
Floral Morphology ◽  
Rhizophora Mangle ◽  
Fruit Production ◽  
Wind Pollination ◽  
Reproductive Systems ◽  
Flower Visitors ◽  
Pollination Limitation ◽  
Propagule Dispersal ◽  
Male Phase ◽  
And Behavior

Rhizophora mangle is considered as a self-compatible mangrove, and is pollinated by wind and insects. However, there is no information about fruit production by autogamy and agamospermy and on the foraging behavior of its flower visitors. Hence, the present study analyzed the pollination and reproductive systems of R. mangle in a mangrove community in northern Pernambuco, Brazil. Floral morphology, sequence of anthesis, and behavior of flower visitors were described; the proportion of flowers that resulted in mature propagules was also recorded. Autogamy, agamospermy, and wind pollination tests were performed, and a new anemophily index is proposed. The flowers of R. mangle are hermaphrodite, protandric, and have high P/O rate. Flies were observed on flowers only during the male phase, probably feeding on mites that consume pollen. Rhizophora mangle is not agamospermic and its fruit production rate by spontaneous self-pollination is low (2.56%) compared to wind pollination (19.44%). The anemophily index was high 0.98, and thus it was considered as a good indicator. Only 13.79% of the flowers formed mature propagules. The early stages of fruit development are the most critical and susceptible to predation. Rhizophora mangle is, therefore, exclusively anemophilous in the study area and the propagule dispersal seems to be limited by herbivory.

Life-form species–area relationships in a temperate eucalypt woodland community

Plant Ecology ◽  
2011 ◽  
Vol 212 (6) ◽  
pp. 1047-1055 ◽  
Author(s):  
John W. Morgan ◽  
Nathan K. Wong ◽  
Seraphina C. Cutler
Keyword(s):  
Life Form ◽  
Species Area ◽  
Eucalypt Woodland

Demography of three perennial grasses in a central Queensland eucalypt woodland

2009 ◽  
Vol 31 (4) ◽  
pp. 427 ◽  
Author(s):  
P. Jones ◽  
P. Filet ◽  
D. M. Orr
Keyword(s):  
Life Span ◽  
Seedling Recruitment ◽  
Negative Impact ◽  
Grazing Pressure ◽  
Perennial Grasses ◽  
Seasonal Rainfall ◽  
Severe Drought ◽  
Heteropogon Contortus ◽  
Heavy Grazing ◽  
Eucalypt Woodland

The population dynamics of the palatable, perennial grasses Bothriochloa ewartiana (Domin) C.E.Hubb. (desert Mitchell grass), Chrysopogon fallax S.T.Blake (golden beard grass) and Heteropogon contortus (L.) P.Beauv. ex Roem. & Schult. (black speargrass), were studied in an extensive grazing study conducted in a eucalypt woodland within the Aristida–Bothriochloa pasture community in central Queensland between 1994 and 2000. Treatments were three grazing pressures based on light, medium and heavy utilisation of forage available at the end of summer and two timber treatments (trees intact and trees killed). Seasonal rainfall throughout this study was generally favourable for plant growth with no severe drought periods. Grazing pressure had a greater overall impact on plant dynamics than timber treatment, which had minimal impact. Grazing pressure had a large impact on H. contortus dynamics, an intermediate impact on B. ewartiana and no impact on C. fallax. Fluctuations in plant density of both B. ewartiana and C. fallax were small because both species were long lived with low levels of seedling recruitment and plant death, whereas fluctuations in H. contortus density were relatively high because of its relatively short life span and higher levels of both recruitment and death. Heavy grazing pressure increased the recruitment of B. ewartiana and H. contortus in some years but had no impact on that of C. fallax. Heavy grazing pressure reduced the survival of the original plants of both B. ewartiana and H. contortus but not of C. fallax. For H. contortus, the size of the original plants was larger where trees were killed than where trees were left intact and plants of the 1995 seedling cohort were larger in 1998 at heavy compared with those at light and medium grazing pressure. Grazing had a minor negative impact on the soil seed bank of H. contortus. Populations of all three species remained stable throughout this study, although the favourable seasonal rainfall experienced and the short duration of this study relative to the life span of these species may have masked longer term, deleterious impacts of heavy grazing pressure.

Response of birds to a wildfire in the Great Western Woodlands, Western Australia.

2013 ◽  
Vol 19 (4) ◽  
pp. 188 ◽  
Author(s):  
Harry F Recher ◽  
William E Davis Jr
Keyword(s):  
Western Australia ◽  
Fire Frequency ◽  
First Year ◽  
Large Area ◽  
Burnt Area ◽  
Open Country ◽  
Second Year ◽  
Eucalypt Woodland ◽  
Number Of Individuals

In December 2005, a wildfire burnt a large area of semi-arid eucalypt woodland along ~10 km of the Norseman- Coolgardie Road north of Norseman in the Great Western Woodlands (GWW), Western Australia. Few birds used the burnt area in the first year after the fire and these were mainly ground and shrub foraging insectivores. There was no influx of seed-eaters or open-country species as reported for post-fire habitats elsewhere in southern Australia. The greatest number of individuals and species of birds occurred in the second year post-fire when ground and shrub vegetation was floristically most diverse. Canopy foragers were attracted to the burnt area in the second year by an outbreak of psyllid insects on seedling eucalypts. At the same time, bark dwelling arthropods associated with the standing stems of fire-killed eucalypts attracted bark-foragers. From the third year, small insectivorous ground, shrub, and canopy foragers dominated the avifauna on the burnt area. These foraged on fire-killed shrubs, as well as living vegetation, including the lignotuberous regrowth of eucalypts. Bark foragers were uncommon after the second year. Throughout the study, the burnt area had fewer species and individuals than adjacent unburnt habitats. Compared with unburnt woodlands there were few differences in how species foraged on the burnt plots, but most species foraged lower reflecting the stature of the vegetation in the burnt woodland. Nectar-feeders, fruit-eaters, large insectivores, raptors, and parrots, although common in the unburnt woodland, were absent or rare in the burnt area. This reflected the limited regrowth of vegetation on the burnt area, which lacked the structural and floristic complexity of nearby unburnt woodlands. Ground foragers probably commenced nesting on the burnt area in the first year, with shrub and canopy foragers nesting from the second year. However, after five years, there was no evidence of large insectivores, nectar-feeders, raptors, seed-eaters, or foliage-eaters (i.e., parrots) nesting despite their abundance in adjacent unburnt woodland. Some of the unburnt woodlands monitored in this study were even-aged regeneration estimated to be 30–50 years post-fire or logging. Regardless of origin, these even-aged plots lacked the diverse avifauna associated with mature woodlands and suggest that post-fire recovery of birds and vegetation in these woodlands is likely to take decades and probably more than 100 years. If so, human activities that increase fire frequency in the GWW, including climate change and fuel-reduction burns, will have long-term adverse impacts on regional biodiversity exceeding those associated with wildfires in less arid forests and woodlands where rates of recovery are more rapid.

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