bluuebunny/crossref_metadata_2025_split huggingface dataset:
Community phenological patterns of a lowland tropical rainforest in north‐eastern Australia
Authors: HOPKINS M. S. , GRAHAM A. W. 
Published: July 2006

AbstractLeaf‐fall, leaf‐flush (newly expanded leaves), flowering and fruiting were recorded monthly between April 1982 and May 1985 in 703 individuals of 99 species of trees, shrubs and herbs in a logged lowland, complex rainforest. Weekly water availability and demand were modelled using pan evaporation, rainfall, and a range of estimated maximum soil water storage. The water balance model indicated that rainfall distribution was an inadequate measure of the seasonal availability of water for growth and reproduction. Intermittent shortages in available water were predicted between October and February, well into what is the wettest season of the year in terms of long‐term rainfall averages. Adequate water was available in soil water stores through most of the August–October ‘dry season’.Leaf‐fall, flowering, and fruiting all followed distinct seasonal patterns although appreciable levels of activity occurred in all months. Community leaf‐fall increased rapidly following an annual low in the very wet, February–May period, to a peak in August. The rapid increase in leaf‐fall activity was accompanied by pronounced depressions in flowering and leaf‐flushing and coincided with the period of minimum temperatures and insolation. There was no evidence to suggest that this leaf‐fall peak was accompanied or induced by drought. This ‘winter’ was followed by rising temperatures and insolation at a time when adequate soil water was usually available, and flowering activity (number of species, number of individuals, and total abundance) increased rapidly in August and peaked from September to October. The flowering peak was accompanied by a major leaf‐flush. Leaf‐flushing continued intermittently from October to February, a period characterized by maximum temperature, maximum insolation, and periods of predicted water stress when soil water stores were depleted during short, rainless periods. A second peak in leaf‐flushing coincided with the wet in March‐April. This was accompanied by a relatively small increase in leaf‐fall activity. Fruiting showed a bimodal peak from October to April each year. Prediction of functional relationships between climate and species and individual behaviour from community phenological patterns was considered to be inappropriate.
Effects of flower removal on abundance and behaviour of honeyeaters in heathland near Sydney
Authors: PYKE GRAHAM H. 
Published: July 2006

AbstractRemoval of almost all honeyeater nectar sources from a 5.6 ha area during February to July had no apparent effect on honeyeater nesting or total abundance. Behaviour in the experimental area was also generally unaffected except for the extent of nectar‐feeding which was significantly reduced for the most commonly observed species. The honeyeaters must have compensated for the nectar removal by flying to nearby productive areas to feed on nectar.Nectar‐removal had no significant effect on the species composition of resident honeyeaters but did affect the species composition of all observed honeyeaters. Nectar removal resulted in a decrease in the abundance of the large and dominant Little Wattlebirds (Anthochaera chrysoptera) and an increase in the abundance of the other, smaller species.
Determinants of bird populations in an urban area
Authors: MUNYENYEMBE F. , HARRIS J. , HONE J. , NIX H. 
Published: July 2006

AbstractThe effects of suburb age and distance from remnant native vegetation on the species richness and density of bird populations in Canberra were studied from June 1982 to May 1983. Mean total number of bird species increased with age of the suburbs < 12 years old. The density of birds also increased with suburb age. The number of open forest and woodland species increased with the age of the suburbs but the number of grassland and exotic species remained largely unchanged. These increases in bird species richness and density represented a response to changes in habitat conditions over time and were not a direct response to the suburb age per se. Such habitat changes reflected the growth of trees and, to a lesser extent, the increased cover of shrubs. The numbers of open forest, woodland and grassland species decreased with distance of suburban sites from native vegetation areas. The number of exotic species, however, remained unaffected. The density of individual birds of grassland and exotic species increased with distance of sites from remnant native vegetation.
Vegetation and soil patterning in semi‐arid mulga lands of Eastern Australia
Authors: TONGWAY D. J. , LUDWIG J. A. 
Published: July 2006

Abstract Vegetation and soil patterns across a 200 ha semi‐arid site 40 km north‐west of Louth, NSW, are described using plant cover data from line transects and soils data from points, sampled systematically (50 m intervals) across the site. A patterned sequence of alternating groves and intergroves with three vegetation types was identified: an Eragrostis eriopoda savanna occurring on runoff slopes (<0.5%) from low ridges, with a Monachather paradoxa savanna occurring at the toe of these runoff slopes (intergroves), followed by an Acacia anuera woodland occurring on runon areas (groves, either as discrete islands or more continuous along drainage lines). Data on landform, micro‐topography, and hydrological features indicate that the grove‐intergrove pattern is maintained by differential erosion–deposition processes similar to the dynamic erosion–transfer–sink geomorphic systems described for Central Australia. This vegetation grove–intergrove patterning in Eastern Australia is similar to, but differs in detail from, such patterns reported for arid and semi‐arid Western and Central Australia. Groves or ‘bands’ of A. anuera in the Centre and the West tend to occur on the downslope side of ‘risers’ or on ‘convex slope‐breaks’ where in the East such groves occur in distinct 'steps’ or ‘flats’ in the landscape; there is a drop into the grove and a sharp ‘erosion‐scarp’ below the grove. A prominent ‘grass band’, identified by cluster analysis as the M. paradoxa community type, occurs immediately upslope of A. anuera groves in the East. The A. anuera groves in the East are also fertile’ patches as soils data demonstrate that groves have much higher levels of organic and exchangeable nutrients (and plant cover) than soils in the intergroves. This paper demonstrates that patterning in mulga lands is more extensive geographically, and has a wider climatic range, than previously reported.
Dieback of rural eucalypts: Response of foliar dietary quality and herbivory to defoliation
Authors: LANDSBERG JILL 
Published: July 2006

Abstract Rural dieback of Eucalyptus blakelyi trees growing on pastoral properties near Canberra is associated with chronic defoliation by insects. In order to test the effect of defoliation on subsequent herbivory, I artificially defoliated three healthy trees by clipping their terminal branchlets. The foliage that regrew on the clipped trees was nutritionally superior to the foliage it replaced, and was much more heavily damaged by grazing insects. There was a transient increase in the tannin content of the regrowth foliage, but this was apparently ineffective in defending it from subsequent herbivory. Compared with the foliage on nearby E. blakelyi trees that also produced major flushes of leaf growth during the same period, the regrowth on the clipped trees had enhanced dietary qualities and suffered more insect damage. Leaf age contributed to many of the differences in dietary quality, but when adjustments were made for the effects of leaf age the same trends remained. Five of the nearby trees were suffering from the chronic insect grazing associated with rural dieback, and the other five appeared healthy. The dietary quality of regrowth foliage on the clipped trees was qualitatively more similar to that of foliage on the dieback trees. Thus the chronic herbivory associated with rural dieback may be partly self‐perpetuating, given this positive feedback between defoliation and dietary quality, and an apparent absence of other effective controls on insect populations.
An analysis of density responses of forest and woodland birds to composite physiognomic variables
Authors: MACNALLY RALPH C. 
Published: July 2006

AbstractHabitat ordinations were performed on 37 sites in forests and woodlands along a latitudinal transect that spanned over 250 km in central Victoria. Australia. Multivariate analyses of these data by using nonmetric. multidimensional scaling (AIDS) were used to generate composite variables. The relationships of these composite variables and densities (by area) of 58 species of forest and woodland birds were assessed by using linear and polynomial regressions. Only seven of the 58 species of birds did not display a significant relationship to one or other of the five composite variables. Approximately 50% of the avian species showed significant relationships with each of the first two composite variables, but lower percentages were observed for the other three variables. About a third of all significant correlations were either of second or third order, ft appears that marked curvilinearities associated with the first composite variable can be interpreted as linear responses with respect to the secondary composite variable. These results suggest that, although composite variables derived from multivariate classifications are statistically independent, there often may be substantial biological dependence between the composite variables. Therefore, for biological interpretation, it would be appropriate to regard composite variables derived from multivariate classifications as suites of related variables. Some authors have traced sharp discontinuities in distributions of species with respect to habitat structure by using presence/absence data alone. This approach appears to be sensitive to sampling of habitat types, and densities should be used wherever possible.
Bioclimatic analysis of the distribution of damage to native plants in Tasmania by Phytophthora cinnamomi
Authors: PODGER F. D. , MUMMERY D. C. , PALZER C. R. , BROWN M. J. 
Published: July 2006

AbstractClimatic profiles were generated by the computer program BIOCLIM for three sets of sites in native vegetation in Tasmania: (i) 308 sites at which Phytophthora cinnamomi was isolated from diseased plants Pc+ ive; (ii) 322 sites in healthy plant communities from which P. cinnamomi could not be recovered Pc−ive; and (iii) 801 sites representing the climatic range across Tasmania. A discriminatory analysis comparing the first and third sets indicated that seven of the 16 climatic indices available for analysis were good discriminators of the distribution of damage by P. cinnamomi. The analysis suggests that damage to native vegetation due to P. cinnamomi is unlikely on sites where annual mean temperature does not exceed 7.5°C or annual mean rainfall is < 600 mm. Two maps were produced to indicate those areas of Tasmania that have climates suited to damaging interaction between P. cinnamomi and native vegetation. The first was based on those sites that had annual mean temperature more than 7.5°C and annual mean rainfall less than 600 mm. The second included those sites that matched the values of the Pc+ ive set for all seven good discriminators. The two approaches produced similar results. Areas in which even the most favourable microsites are unlikely to support pathogenic activity by P. cinnamomi constitute less than 20% of the land area. Twelve substantial areas of native vegetation that occur in climates suited to infection by P. cinnamomi. but for which no record of the fungus exists, have been identified.
Evidence of late Pleistocene fires and eucalypt forest from a North Queensland humid tropical rainforest site
Authors: HOPKINS M. S. , GRAHAM A. W. , HEWETT R. , ASH J. , HEAD J. 
Published: July 2006

AbstractCharcoal fragments, some identified as Eucalyptus, with radiocarbon dates spanning the period 27 000–12 000 years bp, were found in a soil profile under moist tropical rainforest in north‐eastern Australia. The charcoal indicates that sclerophyll forest occupied a central part of the Windsor Tableland rainforest massif during the late Pleistocene. The widespread presence of identifiable and dateable charcoal under rainforest in north Queensland provides an opportunity to examine the patterns and ecological implications of fluctuations in rainforest distribution in recent history.
Ecology of sessile animals on sublittoral hard substrata: The need to measure variation
Authors: BUTLER A. J. , CHESSON P. L. 
Published: July 2006

AbstractThis paper concerns assemblages of sessile animals occupying shaded, commonly vertical hard substrata in the shallow subtidal zone. We are interested particularly in questions about the coexistence of species and about what influences their joint dynamics. We propose a conceptual model which focuses on variation in characteristics such as birth and death rates, competitive interactions and dispersal.We argue that, qualitatively, this model appears to be a satisfactory representation of the important characteristics of certain sessile assemblages. Further, we suggest that it may explain the coexistence of a large number of ecologically similar species in assemblages that appear in a sense ‘stable’ (but where assemblages at different sites differ in detail). There is support for this assertion from formal theoretical work on simpler versions of the model.It is not sufficient merely to argue that the model seems satisfactory or plausible, so we finally consider what kind of data is needed for the further development and testing of this kind of model.
Mutualistic interdependence between mistletoes (Amyema quandang), and spiny‐cheeked honeyeaters and mistletoebirds in an arid woodland
Authors: REID NICK 
Published: July 2006

AbstractThe mutualism involving mistletoes (Amyema quandangj, spiny‐cheeked honeyeaters (Acan‐thagenys rufogularis) and mistletoebirds (Dicaeum hirundinaceum) was studied in arid woodland in South Australia between 1980 and 1984. Plants and birds were locally interdependent: mistletoes supplied a continuous resource of fruits or nectar that sustained permanent populations of pollinators (honeyeaters) and dispersers (honeyeaters and mistletoebirds). The reproductive phenology of Amyema quandang was central to the interactions. Amyema quandang flowered in winter and annual fruit crops overlapped so that ripe fruit was continuously available. Spiny‐cheeked honeyeaters obtained most of their energy requirements from mistletoe nectar in winter and mistletoe fruit in summer. Higher honeyeater densities were sustained by flowering in winter. Mistletoebirds were present in low density throughout the year and subsisted on a diet of mistletoe fruit and a few insects.The reproductive strategy of A. quandang probably evolved in response to the pollination and dispersal service provided by honeyeaters in inland Australia. Neither spiny‐cheeked honeyeaters nor mistletoebirds have adaptations resulting from evolutionary interactions with A. quandang. The high specificity of their mutualism is a result of: (i) the abundance of A. quandang in relation to other nectar and fruit producing plants in the community: (ii) the year‐round production by A. quandang of the primary source of fruit or nectar for honeyeaters and mistletoebirds: (iii) the facultative specialization of both birds on A. quandang; and (iv) the reluctance or inability of other frugivorous birds in the community to consume A. quandang fruit.
Habitat selection in the White‐plumed Honeyeater and the Fuscous Honeyeater at an area of sympatry
Authors: CHAN K. 
Published: July 2006

AbstractMultivariate analysis on 15 habitat variables and quantitative data on foraging and interactive behaviour were used to investigate habitat selection in the White‐plumed Honeyeater (Lichenostomus penicillatus) and the Fuscous Honeyeater (Lichenostomus fuscus) at an area of sympatry in woodland in New England Tablelands. Thirty‐nine plots from four sites were used to examine significant differences in habitat utilization during the breeding period. The White‐plumed Honeyeater associated strongly with narrow belts of riverine Casuarina while the Fuscous Honeyeater was associated with Eucalyptus in the extensive eucalypt woodland. The narrow ecotone was used by both species, but the two occurred together only in an extremely narrow zone. Changes in foraging activities were observed between this overlap zone and non‐overlap zone. Both niche breadth and overlap in relation to four measures of foraging were reduced in plots where species were in joint occurrence compared with where they were not, although overlap in most measures of foraging remained high. The number of encounters between the two highly aggressive and abundant species was not great. Thus, the species appear generally to avoid each other. The observed spacing pattern may result from prior experience of intense aggressive interactions. Distinct habitat features could provide easily recognized cues for the maintenance of local horizontal separation. Other factors such as slight differences in morphology, habitat preference, foraging and physiology may enhance differences in habitat selection.
Habitat peculiarity as a cause of rarity in Eucalyptus paliformis
Authors: PROBER SUZANNE M. , AUSTIN M. P. 
Published: July 2006

Abstract Eucalyptus paliformis is a rare species of the Wadbilliga Plateau in southeastern Australia. The hypothesis that rarity in E. paliformis is a result of restriction to a rare habitat was addressed by means of a floristic survey comparing sites where E. paliformis occurs with similar sites where it is not known to occur. Mathematical models describing mean annual rainfall and mean annual temperature regimens experienced in southeastern Australia were used to locate areas with a climate similar to E. paliformis sites. Understorey vegetation of E. paliformis sites was then compared with that of climatically similar areas using a stratified random sampling procedure. Similarity in floristic composition was used as an integrated measure of habitat similarity. Detrended correspondence analysis of the floristic data suggested that E. paliformis sites are unique. No single environmental factor was sufficient to describe E. paliformis sites—rather, their peculiarity could be ascribed to a unique combination of environmental factors. Within the Wadbilliga area, temperature or moisture parameters relating to marginally higher elevation or low relative radiation index may be important. Non‐metric multidimensional scaling of the floristic data revealed similar environmental trends in the data, but support for habitat peculiarity in E. paliformis was weaker.
Ecological association of habitats and bird species during the breeding season in southeastern New South Wales
Authors: RECHER H. F. , KAVANAGH R. P. , SHIELDS J. M. , LIND P. 
Published: July 2006

AbstractBird communities in southeastern New South Wales, as determined by classification and ordination techniques, were seldom discrete. The most cohesive assemblage was associated with wet sclerophyll and rainforest habitats. These moist forests also supported the richest avifaunas and had high population densities. Although most birds occurred throughout the region, most species were uncommon. Of the 116 species recorded, 51 (44%) were found on fewer than 10% of the 143 plots censused. Only 19 species occurred on more than half the plots, with six of these recorded on more than 90% of the plots. Other than a small group of birds primarily restricted to moist forest, only the most common and widely distributed species regularly occurred together. Species were grouped with habitats on an elevational gradient from coastal forests to the tablelands. Within this elevational range, species were associated with major structural features of the vegetation. In terms of bird assemblages, open habitats were distinguished from those with dense vegetation. Plots which had been recently logged were separated from mature forest. The results indicate that plans for wildlife management should consider both the assemblages of species which are associated with major forest habitats and the requirements of individual species.
Assessing the effects of fire on vegetation in tropical savannas
Authors: LONSDALE W. M. , BRAITHWAITE* R. W. 
Published: July 2006

AbstractBecause of its high frequency and generally low intensity, fire in tropical savannas appears to be a different phenomenon from that in other biomes. A recent study of fire in savanna at Munmarlary in northern Australia, analysed by detrended correspondence analysis (DCA) concluded that different fire regimens resulted in negligible changes in the vegetation, a conclusion crucial for fire management in the region.Here, we describe the short‐term impact of an unusually intense fire in an area of tropical open forest. Tree and shrub mortality of 14.3% was recorded within 6 months of the fire, and the composition of the vegetation was changed because of differences between species in mortality rates, which ranged from 4 to 90%. Analyses of variance (ANOVA) of DCA co‐ordinates were unable to detect any change, however. DCA seems inappropriate for analysing vegetation changes after savanna fires, because the floristic changes, compared with those in temperate fire‐prone ecosystems, are subtle and multidirectional.Further, it is shown that rather large plot sizes (2–4 ha) are likely to be required to detect fire treatment differences even as great as about 20% of the mean, given the variability of savanna vegetation, and replicates that are likely to be limited in number. A possible solution is to measure the change over time in permanent plots, rather than attempting to detect treatment differences by sampling on a single occasion.
An evaluation of hypotheses to explain the pattern of sap feeding by the yellow‐bellied glider, Petaurus australis
Authors: GOLDINGAY ROSS L. 
Published: July 2006

AbstractYellow‐bellied gliders on occasion extensively incise the trunks of eucalypts to feed on sap but in doing so show strong preference for the species and number of trees utilized. Three hypotheses that may account for aspects of this behaviour were examined. They were: (i) sap feeding is related to the incidence of rain; (ii) sap feeding is influenced by the sap flow idiosyncracies of trees; and (iii) sap feeding is influenced by the availability of alternative food resources. Sap feeding at two sites occurred independent of ‘wet’ or ‘dry’ nights. Sap flow (measured as an index) in two species of eucalypt was highly variable among trees and among sample periods. This is the only hypothesis that accounts for the selectivity of the trees incised. Sap feeding at one site coincided with periods of high sap flow. However, at another site, sap feeding did not occur on measured trees despite their often high sap flow. At such times, flowering trees were abundant and gliders fed extensively on nectar. Thus, elevated sap flow may provide the necessary precondition conducive for sap feeding but may be ignored when other food types are available.