bluuebunny/crossref_metadata_2025_split huggingface dataset:
Herbivory and patch dynamics on rocky reefs in temperate Australasia: The roles of fish and sea urchins
Authors: JONES G. P. , ANDREW N. L. 
Published: July 2006

AbstractSea urchins are widely considered to be the major grazers in temperate subtidal systems, with herbivorous fish being browsers of minor importance. This paper reviews spatial and temporal patterns in these herbivores on rocky reels in temperate Australasia, with the aim of assessing their relative impacts on patch structure and dynamics. Herbivorous fishes are widespread and make up a significant numerical component the reel fish fauna. Sea urchins are also abundant, but not all geographic locations support actively grazing species.Both fish and sea urchins exhibit distinct patterns of distribution among depth strata. Within depth strata, all herbivores are restricted to (sea urchins) or forage preferentially in (fish) particular habitat patches, causing a mosaic of different feeding activities. These patches are either related to specific features of the habitat (e.g. Kelp patches, topography) or behavioural interactions. Foraging by sea urchins and demersal‐nesting damselfishes is intense and persistent, whereas in the kelp‐feeding fish Odax cyanomelas, foraging reaches greatest intensity at predictable locations during a few months of every year.Many fish and sea urchins consume some algae in preference to others. However, feeding preferences may determine the nature of the impact only in fishes. For sea urchins, preference may occasionally determine the order in which algae are consumed, but at high densities they consume all available macroalgae.Impacts of both types of herbivore on the abundance of algae have been recorded. Some sea urchins (e.g. Evechinus chloroticus, Centrostephanus rodgersii) appear to severely modify biogenic habitat structure by maintaining ‘barrens’ (areas devoid of macroalgae) over long periods. In contrast to this, the effects of fishes may be more transitory (e.g. seasonal impact of Odax cyanomelas on brown algae) or occur at smaller spatial scales (e.g. nest sites maintained by male Parma victoriae) Herbivorous and other fishes appear to respond to spatial patterns in algal distributions, rallier than having it major impact upon them. The relative effects of fish and sea urchins on the long‐term dynamics of kelp forests are unknown, hut temporal patterns in herbivore abundance and behaviour, and algal demography arc urgent targets for research.
Species‐area curves and growth‐form spectra for some herb‐rich woodlands in western Victoria, Australia
Authors: LUNT IAN D. 
Published: July 2006

AbstractSpecies‐area curves are presented for three woodlands with herbaceous understoreys in western Victoria. Australia. Up to 93 species of vascular plant were recorded from 128 m2. making these woodlands one of the richest terrestrial vegetations recorded from temperate Australia. Species richness at this scale is comparable with that recorded from kwongan (sclerophyllous shrubland) in south‐western Australia. Up to 45 species were recorded from 10 m2. At this scale the woodlands are the richest terrestrial vegetation recorded from Australia, and among the richest in the world, being comparable with the renowned chalk grasslands of Europe. The growth‐form spectra of these woodlands differ dramatically from those of other species rich communities in temperate Australia due to the abundance of herbs and dearth of woody species. In contrast to species rich woodlands in Israel and California, perennial herbs rather than annuals predominate. Although the woodlands studied are protected in conservation reserves, regional floristic surveys are required to determine the geographic extent, floristic variability and conservation status of herb‐rich woodlands in Victoria.
Sandstone vegetation pattern in the Jim Jim Falls region, Northern Territory, Australia
Authors: BOWMAN D. M. J. S. , WILSON B. A. , FENSHAM R. J. 
Published: July 2006

AbstractAnalysis of 58 floristic quadrats from two areas near Jim Jim Falls on the Arnhem Land Plateau revealed seven plant communities: wetland; monsoon forest; Allosyncarpia forest; broadleaf woodland; shrubby Eucalyptus woodland; Eucalyptus arnhemensis woodland; and sandstone scrub. The communities inter‐grade with each other and form a complex mosaic. The patterning of vegetation is related to topography, rockiness, degree of fire protection and moisture supply. Surface soil nutrient concentrations were similar in all the communities with the exception of the monsoon forest which was substantially more fertile. We suggest that moisture supply is the primary determinant of vegetation and soil fertility patterns. Fire in the preceding dry season stimulated some herbaceous species, while a long unburnt shrubby Eucalyptus woodland was invaded by some monsoon forest seedlings. Conservation of the present mosaic of vegetation presents a major challenge to land managers because of this variable impact of fire.
Woody overstorey impact on herbaceous understorey in Eucalyptus spp. communities in central Queensland
Authors: SCANLAN J. C. , BURROWS W. H. 
Published: July 2006

AbstractNative pasture yield and species composition within naturally occurring Eucalyptus communities of central Queensland were studied. Within a site, herbaceous yield decreased as tree basal area increased with the greatest relative decrease at sites with low pasture production potential. Mitscherlich regressions between herbaceous yield and tree basal area Y = A + B*e−kx) accounted for >80% of the observed variation at all sites. The absolute value of ‘k’ was greatest for those sites that had the lowest yield in the absence of trees.Pasture composition in treeless plots varied widely among sites. However, the direction of species compositional change was similar for all sites except one subject to short‐term inundation on a heavy clay soil. Grass tribes differed in their occurrence in areas of high tree basal area. Andropogoneae had lower actual yield and percentage composition (by dry weight) at high tree basal area, while Paniceae showed the reverse trend. Non‐grass herbaceous plants made a greater contribution to pasture composition at higher tree basal area although actual dry matter yield remained relatively constant over a wide range of basal areas.
Dispersal of an introduced shrub (Crataegus monogyna) by the Brush‐tailed Possum (Trichosurus vulpecula)
Authors: BASS DAVID A. 
Published: July 2006

AbstractThe Brush‐tailed possum Trichosurus vulpecula eats the fleshy fruits of the introduced shrub Crataegus monogyna and defaecates intact seeds at least 0–50 m away. Viability of seeds recovered from faeces was >73%. comparable to the viability of fresh seeds (87.6%). Seed dispersal by possums has been largely neglected and may have important implications for invasion by woody weeds in Australasia.
Disturbance regimes in North Queensland rainforests: A re‐evaluation of their relationship to species richness and diversity
Authors: SAXON E. C. 
Published: July 2006

AbstractChanges in tree species richness and diversity after logging and natural disturbance on small rainforest plots in north Queensland were studied by Nicholson et al. (1988). They found logging had enhanced richness and diversity, which declined in its absence. A re‐evaluation of their data, especially those on the predisturbance condition of these plots, indicates that their conclusions are untenable.
Recolonization of regenerating open forest by terrestrial lizards following sand mining
Authors: TWIGG LAURIE E. , FOX BARRY J. 
Published: July 2006

AbstractThe terrestrial lizard fauna of a regenerating mining path situated in open forest on coastal sand dunes was surveyed by pitfall trapping. The regeneration age of the series of chronosequence plots used ranged from 3.9 to 15.9 years. No lizards were recorded on plots less than 5.9 years old. Only four species of lizard were regularly found on the mining path. The skink Ctenotus robustus was the first colonizer and attained peak abundance and biomass after 9 years’ regeneration. Amphibolurus muricatus and Ctenotus taeniolatus were less abundant than C. robustus and did not appear on the mining path until 9 to 11 years’ regeneration. The abundance of C. taeniolatus continued to increase up to the oldest age class (16 years). Linear multiple regression analysis showed that sparse patchy vegetation in the 0–1 m layer and the amount of live shrub cover jointly accounted for 72% of the variance in abundance and 68% of variance in biomass for C. robustus. Fifty percent of the variance in C. taeniolatus abundance was explained by the proportion of plant species endemic to forest, regeneration age and the patchiness in understorey vegetation height. However, 67% of C. taeniolatus biomass was accounted for by plant species richness, plant species diversity, and the proportion of endemic forest and heath plant species. Some lizard species recorded from the surrounding forest were not found on the mining path. Lizards appear to recolonize revegetated areas more slowly than some other animal groups; this ‘sensitivity’ implies that they can act as important ‘indicator species’ of successful regeneration in disturbed areas. The non‐linear response with time of some habitat variables makes it difficult to predict the time required for the complete rehabilitation of the mining path; however, it seems likely that a period well in excess of 20 years may be necessary before the lizard fauna on the mining path reaches premined levels.
The ecology of Lagarostrobos franklinii (Hook.f.) Quinn (Podocarpaceae) in Tasmania. 1. Distribution, floristics and environmental correlates
Authors: GIBSON N. , DAVIES J. , BROWN M.J. 
Published: July 2006

AbstractA state‐wide survey of the endemic Tasmanian podocarp Lagarostrobos franklinii (Huon pine) resulted in the recognition of four major community types largely restricted to the river systems of western and southern Tasmania. Continuous variation was found between most of these communities. The floristic variability was found to be correlated with temperature, rainfall and geological gradients. It is suggested that the restricted nature of Huon pine distribution in Tasmania is associated with a slow terrestrial dispersal rate rather than a narrow fundamental niche. There is some evidence to suggest that the species has been further restricted by fire.
Decomposition of eucalypt litter on rehabilitated bauxite mines
Authors: WARD S. C. , MAJER J. D. , O'CONNELL A. M. 
Published: July 2006

AbstractThe initiation of nutrient cycling is important in developing a self‐sustaining ecosystem, where inputs of fertilizer are not required, on rehabilitated open‐cut mines. The loss of dry weight, surface area and nutrients from senescent jarrah (Eucalyptus marginata) leaves enclosed in litterbags for 18 months were measured on 27 rehabilitated bauxite mines and in two jarrah forests on the Darling Plateau in Western Australia. Respiration and acetylene reduction by the litter were also determined. Linear trends were found between litter decomposition on rehabilitated mines and understorey cover density, litter cover and a measure of the effect of the revegetation on soil moisture. During decomposition, N was retained relative to litter dry weight and, in most cases, amounts of N increased. Losses of Ca and S were correlated with dry weight losses. Sodium, Cl, Mg and K were lost from the litter by leaching. Rehabilitation techniques, including sowing a legume understorey and replacement of the topsoil, should favour the development of nutrient cycling on mined areas.
The nutrient capital of indigenous Sorghum species and other understorey components of Savannas in north‐western Australia
Authors: COOK G. D. , ANDREW M. H. 
Published: July 2006

AbstractIndigenous Sorghum species dominate the understorey of the savannas of tropical northwestern Australia. The nutrient capital of these grasses was investigated and the consequences for nutrient cycling, the effects of fire, and herbivory were discussed.The macronutrient concentrations in two annual species, S. intrans and S. stipoideum indicated that their growth was nutrient limited. The breakdown of litter may provide up to one quarter of the N yield of S. intrans, hence losses of N due to dry season fires, which consume this litter, may reduce grass growth. However, this effect was not apparent after one fire. From the first sampling, approximately 60 days after germination, until maturity, the herbage of S. intrans and S. stipoideum contained insufficient N and P to maintain the liveweight of cattle. Translocation to the inflorescence during seed set left the herbage grossly deficient for livestock maintenance during the dry season. The relative lack of large native herbivores is consistent with this poor herbage quality.Nutrient concentrations in the seeds of nine Sorghum species (including two perennials) were measured. The concentrations were relatively high, which accounts for the importance of the seeds of the indigenous Sorghum species for granivorous rodents, birds, and ants. Macro‐nutrient concentrations were similar in both annual and perennial species.
Coevolution of mistletoes and frugivorous birds?*
Authors: REID NICK 
Published: July 2006

AbstractSmall frugivorous birds that feed largely on the fruits of stem‐parasitic mistletoes have independently evolved in various parts of the world. Local populations of mistletoes may be dispersed almost exclusively by these birds. Four attributes of mistletoe dispersal systems may have enhanced the evolution of reciprocal dependence between mistletoes and specialized dispersers:(1) Safe sites for mistletoe seeds (i.e. the young branches of a compatible host) are precisely defined in space and time.(2) The viscidity of mistletoe seeds induces smaller dispersers to deposit seeds in safe sites.(3) Frugivores differ markedly in the efficiency with which they disperse mistletoe seeds to safe sites.(4) Relatively large viscid fruits and adaptive fruiting displays exclude or deter most members of the potential disperser guild.Some birds have anatomical adaptations as a result of dietary specialization on mistletoe fruit, and some mistletoes have fruiting displays that target specialized birds or a narrow disperser spectrum. Coevolution between guilds of mistletoes and specialized dispersers is therefore probable. The uncoupled selective pressures that might have driven their coevolution are the mistletoes’ provision of fruit crops that are unavailable to more generalized frugivores, in return for seed dispersal to the small stems most suitable for infection. As in other mutualistic seed dispersal systems, phylogenetic, ecological and life history factors constrain the evolution of monophyletic interdependence, resulting in varying degrees and patterns of reciprocal specificity between mistletoes and dispersers.
Characteristics and abundance of vertebrate‐dispersed fruits in temperate wet sclerophyll forest in southeastern Australia
Authors: FRENCH KRISTINE 
Published: July 2006

AbstractThe diversity, abundance and display characteristics of plants producing fleshy fruits were recorded in wet sclerophyll forest near Melbourne, Victoria. Fruit characteristics and nutrient content were recorded for 14 species of fruits occurring in the forest and these characteristics compared with similar studies in north temperate and tropical regions. Plants producing fleshy fruits were confined to understorey layers and comprised 13.5% of the native vascular flora. Most species displayed fruits conspicuously by ripening brightly coloured fruits synchronously in large displays. Annual fruit production at three sites ranged from 6.98 to 37.01 kg/ha. Fruit mass, seed number and size were variable but the proportion of pulp per fruit remained remarkably consistent between species. Most fruit pulp contained high quantities of soluble carbohydrates and little lipid or protein. Fruits from wet sclerophyll forest did not differ from fruits from other geographic areas in eight characteristics measured. Although taxonomically distinct, the species in wet sclerophyll forest were not significantly different from other temperate fruits, suggesting that fruit characteristics are under the influence of factors other than phylogeny.
Predicting patterns of post‐fire germination in 35 eastern Australian Fabaceae
Authors: AULD TONY D. , O'CONNELL MICHAEL A. 
Published: July 2006

AbstractGermination in 35 species from 15 legume genera of southeastern Australia was promoted by a heat treatment which broke the seed coatcaused dormancy. Once the critical temperature was reached, most seeds had their dormancy broken, independent of the duration of heating. Species fell into three classes according to whether their dormancy was broken by a temperature of 40, 60 or 80°C.Highest germination in all species was achieved by heating in the temperature range 80–100°C, although long durations (120 min) at 100°C caused seed death in several species. At 120°C, seeds of most species were killed at all but one minute's duration. A proportion of seeds from 7 species (Acacia myrtifolia, Pultenaea daphnoides, P. incurvata, P. linophylla, P. polifolia, Dillwynia floribunda and Sphaerolobium vimineurn) was not killed at 120°C and had their dormancy broken. This proportion varied markedly and resultant germination levels were significantly less than those at 80 and 100°C, except in S. vimineum.Between‐site variations in the 4 species tested (A. myrtifolia, A. suaveolens, A. terminalis and A. ulicifolia) were small. These variations concerned: (i) the minimum temperature required to break seed dormancy in 2 species: 60°C in one population of A. myrtifolia and A. suaveolens, and 80°C in the other; and (ii) the intensity of the germination response.Duration of heating was less important than temperature as a determinant of germination. Ordination techniques revealed that results from one duration across temperatures were comparable with data from multiple durations. This has significant applications in studying rare species, where seed may be in short supply.Predicted germination levels after a moderate intensity fire should far exceed those after a low intensity fire. Little germination was predicted for many species after a low intensity fire and for one species, A. elongata, no germination was predicted. The potential role of indicator species in relation to the maintenance of species in a community is suggested.
Germination and seedling development of two mistletoes,Amyema preissiiandLysiana exocarpi: Host specificity and mistletoe‐host compatibility
Authors: VAN ZHAOGUI 
Published: July 2006

AbstractPotential hosts had no effect on seed germination of the mistletoes,Amyema preissiiandLysiana exocarpi, but affected seedling holdfast formation and leaf emergence. ForA. preissii, formation of the holdfast and emergence of leaves occurred most rapidly in seedlings on its usual host,Acacia nyssophylla. Among the six species inoculated withL. exocarpiseeds, formation of the holdfast was quickest onA. nyssophyllaandMyoporum platycarpum(usual hosts). Emergence of leaves was quickest in seedlings onA. nyssophylla, and on two non‐hosts,Eucalyptus oleosaandExocarpos aphyllus. For both mistletoe species, seedling mortality was high during the first 3 months, with considerable variation among different host species. After 6 months, little or no mortality was recorded on seedlings growing on their usual hosts. In contrast, seedlings on non‐host species suffered continuing mortality and none survived the study period, except for 13% of theL. exocarpiseedlings, which persisted onGeijera linearifoliain a moribund state.The growth of seedlings on host and non‐host species varied markedly. After 35 and 47 months, the average length of the longest shoot of two cohorts ofA. preissiiseedlings was 22 and 75 cm, respectively. After 47 months, the average length of the longest shoot ofL. exocarpiseedlings onA. nyssophylla, H. oleifoliumandM. platycarpumwas 57, 38 and 41 cm, respectively. For both mistletoe species, a proportion of individuals on host species flowered and subsequently set fruits within 3 years. In comparison, none of the plants sown on the non‐host species grew beyond seedling stage. The inability ofA. preissiiandL. exocarpito establish on non‐host species was attributed to mistletoe‐host incompatibility.
Survival of serotinous seedbanks during bushfires: Comparative studies of Hakea species from southeastern Australia
Authors: BRADSTOCK R. A. , GILL A. M. , HASTINGS S. M. , MOORE P. H. R. 
Published: July 2006

Abstract
The study assessed the survival, during bushfires, of seedbanks of six serotinous Hakea species found in the Sydney region of southeastern Australia. The survival of seeds was examined when fruits were heated in a muffle furnace at ambient temperatures ranging from 200–800°C for 1 min. For each species, fruit weight and dimensions of fruit walls were measured to characterize insulation. A field experiment was performed to examine the survival of the serotinous seedbank of Hakea dactyloides in a bushfire. Ambient and internal fruit temperatures were recorded during the fire. The viability of seeds from fruits exposed to the fire was tested and compared with an unburnt sample.Viability of seeds within fruits exposed in the furnace varied according to species. Seeds of large fruited species such as Hakea constablei and Hakea propinqua survived, whereas those of the small fruited species Hakea teretifolia and H. dactyloides suffered significant mortality. The threshold temperature for death in four species was linearly related to the thickness of lower and lateral fruit walls, and to dry weight of fruits.Internal and external temperatures of fruits decreased with increasing height on experimental H. dactyloides plants in the field. High levels of mortality (relative to the unburnt control) corresponded with fire temperature maxima greater than 400°C (external) and greater than 60°C (internal). In general, these temperatures occur when shrub crowns burn. A high risk of death for H. dactyloides, H. teretifolia and H. sericea seeds will result because fruits of these species have thin walls.
The rapid and long‐lasting growth of grasses following small falls of rain on stony downs in the arid interior of Australia
Authors: HUNTER D. M. , MELVILLE M. D. 
Published: July 2006

Abstract
Stony downs consist of grassy areas that alternate with areas that have a substantial stone cover. The stone‐covered areas are impermeable, and most rain falling on them runs off, substantially increasing the effective rainfall in adjacent grassy areas. As a result, 20–25 mm of rain on stony downs wetted the soil around the grass to a depth of 140–170 mm and allowed sustained grass response. This is much less than the 35–40 mm of rain required for the same response on red clay or grey clay plains.Grasses respond very rapidly after rain. Some have green shoots the day after rain, and all have responded by the second day. Ephemerals dry off in 4–6 weeks, but most tussock grasses still have some green foliage 8–10 weeks after rain. Deeper rooted tussock grasses remain green for so long because most of the moisture that reaches deeper roots after rain remains there. Most moisture loss is through the soil surface and is recognizable as a drying front that descends through the soil profile. Soil above the drying front is nearly air dry (<5% moisture) while soil below the front has substantial moisture (14–16%). By about a month after rain in summer, the drying front is at a depth of about 80–120 mm. This is near the tips of the roots of ephemeral grasses and the ephemerals then dry off rapidly. Only the tips of the leaves of deep rooted grasses like Mitchell grass (Astrebla spp.) dry off. Their leaves continue to remain mostly green during most of the second month after rain and they do not dry off completely until the third month when the drying front reaches the bottom of the main root system.