Grassland In South-eastern Australia Research Articles

Habitat structure and an introduced predator limit the abundance of an endangered ground-nesting bird.

Understanding the factors that limit the abundance of threatened species is critical for the development of effective conservation strategies. However, gaining such knowledge from monitoring programs and using it to inform decision-making for rare species can be difficult due to methodological issues posed by the problems of distinguishing true absences from false absences and the analysis of datasets dominated by zero counts. The plains-wanderer (Pedionomus torquatus) is a critically endangered ground-nesting bird that occurs in grasslands of southeastern Australia. Decline of the plains-wanderer has been attributed to habitat modification but little emphasis has been placed on the role of introduced predators, such as the red fox (Vulpes vulpes), which have had a devastating effect on small ground-dwelling vertebrates in dryland regions of Australia. Here, we use a 9-year time series of spotlight counts to investigate the impact of vegetation structure and fox presence on plains-wanderer occupancy and abundance. We used distance sampling to determine the effective strip width for sighting plains-wanderers during spotlight surveys. We then used a hurdle model approach whereby binomial generalized additive models were fitted to presence/absence data within the effective strip-width across all sites and negative-binomial models were fitted to an index of abundance at sites where plains-wanderers were observed. Plains-wanderer occupancy and abundance fluctuated markedly through time. Where foxes were absent, occupancy (but not abundance) of plains-wanderers showed a humped relationship with grass height with an optimal height between 50 and 150 mm. Where foxes were present however, this relationship broke down and plains-wanderers were rarely recorded. Our results suggest that plains-wanderers should benefit from management strategies that maintain grass height at optimal levels and exclude foxes or effectively suppress their populations. A key message from this study is that if statistical analyses of data generated by monitoring programs for rare species are intended to inform management decisions by identifying relationships between threatened species and drivers of their abundance, there should be consideration of analytic approaches that account for true and false zeroes, high prevalence of zeroes, and the possibility of nonlinear responses.

A new species of Delma Gray 1831 (Squamata: Pygopodidae) from the Hunter Valley and Liverpool Plains of New South Wales.

The Striped Legless Lizard Delma impar Fischer 1882 occurs in grasslands of south-eastern Australia where it is sometimes sympatric with several congeners. Previous molecular analyses have revealed mitochondrial divergence between the northern and southern lineages of D. impar, but the status of a recently detected population assigned to the species in the Hunter Valley of New South Wales (NSW), 250 km north of other populations, remains unknown. Via morphological and molecular analyses across the known distribution of D. impar, we distinguish the population from the Hunter Valley, Liverpool Plains region as a unique taxon and describe this species as D. vescolineata sp. nov. The new species is divergent from D. impar in both nuclear and mitochondrial analysis, and differing facial scalation and colour patterning from the limited number of specimens available. The degree of mitochondrial and nuclear divergence between the previously identified northern and southern clades of D. impar is consistent with a single species. This is the first description of a Delma from south-eastern Australia since 1974, but the second new vertebrate taxon identified from the Hunter Valley region within a decade. Our research highlights our incomplete understanding of the biodiversity of the Hunter Valley region, despite its relative proximity to populous areas. The range of D. vescolineata sp. nov. is restricted and heavily overlaps with major habitat modification including mining and grazing, with no parks or reserves in this distribution protecting the species grassland habitat. Gathering more data to understand conservation status of this species should be a priority.

Perennial pasture grass invasion changes fire behaviour and recruitment potential of a native forb in a temperate Australian grassland

Invasive grasses can modify fire regimes of native ecosystems leading to changed ecosystem structure, composition, and functioning. Temperate grasslands in Australia are currently being invaded by a suite of exotic perennial pasture grasses, but their effects on ecosystems remain largely unknown. We aimed to determine the effect of invasion by the exotic perennial grass Phalaris aquatica on fire behaviour, as well as the regeneration potential of an endangered forb in temperate native grasslands in south-eastern Australia. Frequently burnt native grasslands invaded by exotic grasses were found to have two times more fuel than grasslands dominated by native grasses; in less-frequently burned native grasslands, exotic grasses contributed to fuel loads that were five times higher than native grasslands. Exotic-dominated grasslands burned differently than native grasslands; fire intensities were three times higher in exotic-dominated grasslands and had a wide variability in fire residence times. Soil heating was positively related to fire residence time but had no clear relationship with fire intensity. Seed germinability of Leucochrysum albicans var. tricolor (Hoary Sunray, Asteraceae) was reduced by exotic grass-fueled fire and increasing fire residence times. The observed changes in fire behaviour represent an invasion-driven shift in the ecosystem’s fire regime. By increasing fuel mass, fire residence time increased, and this influenced seed survival and subsequent germinability. Increased fire intensity following invasion highlights that invasive grasses can increase the fire-risk of grasslands. Maintaining native grasslands free of invasive pasture grasses therefore has environmental and fire-risk benefits.

Moths in fragments: insights into the biology and ecology of the Australian endangered golden sun moth Synemon plana (Lepidoptera: Castniidae) in natural temperate and exotic grassland remnants

The conservation and management of endangered species requires an adequate understanding of their biology and ecology. Although there has been an increasing appreciation in Australia of the need for greater efforts to conserve insects, there is only limited information available that can be used to underpin conservation efforts. The endangered golden sun moth, Synemon plana (Lepidoptera: Castniidae) is a flagship species endemic to natural temperate grassland in south-eastern Australia. Most populations of this species are at considerable risk from habitat loss, weed invasion and inadequate management. Despite the considerable knowledge that exists about the species biology and ecology, efforts to improve the species conservation status are hampered because there are still critical gaps in our understanding of the species’ natural history. In particular, the ecology of the larvae is not known. Our study examined the abundance, population structure and reproductive biology of the moths in a broad sample of both natural temperate and exotic grassland remnants in and near Canberra in the Australian Capital Territory (ACT) in south-eastern Australia. The results fill critical gaps in the knowledge needed to achieve effective conservation management. From our findings, it is clear that the species inhabits grasslands dominated by a mixture of native wallaby grasses (Rytidosperma spp. (formerly Austrodanthonia)) and spear grasses (Austrostipa spp.). In contrast to earlier suggestions that S. plana is entirely confined to natural temperate grassland, mature and immature life stages of the species were also present in grasslands comprised entirely of the exotic Chilean needlegrass (Nassella neesiana). Most of the S. plana populations surveyed in the ACT were characterised by low relative abundance with only very few large populations being recorded. The conservation of exotic grasslands as substitute habitat for S. plana is discussed and suggestions regarding future monitoring and research of the species are provided.

Manipulating livestock grazing to enhance native plant diversity and cover in native grasslands

Temperate perennial grasslands globally have been subject to extensive biodiversity loss. Identifying livestock grazing regimes that maintain and enhance the diversity and cover of native plant species in these ecosystems remains a key challenge. The responses of vegetation to different sheep grazing regimes were assessed over 3 years in grasslands of south-eastern Australia. An open communal experimental design was used to assess the effects of varying season and duration of exclusion of grazing by sheep, replicated at three locations. Manipulation of season and duration of exclusion of grazing led to few major changes in the cover of native perennial grasses or forbs, although seasonal variation was considerable. Exclusion of grazing in the spring did increase the likelihood of occurrence of grazing-sensitive native forb species but also lead to an increase in the cover of exotic annual species. However, cover of exotic annual species tended to decline with increasing duration of exclusion, while the abundance of native, grazing-sensitive forbs and the cover of perennial grasses increased. Small-scale richness of native perennial forb species increased with a 3-month period of exclusion of grazing, but declined with year-round exclusion of sheep. Total species richness also declined in response to year-round exclusion of sheep and rates of decline were correlated with the rate at which herbage mass accumulated. While strategic grazing did not result in major vegetation changes in the short term, it is suggested that some grazing exclusion may enhance the survival of infrequent species most sensitive to sheep grazing. Caution, however, should be taken when grazing regimes implemented benefit both desirable (native forbs) and undesirable (exotic annuals) species. Having a mosaic of flexible grazing management regimes across the landscape is likely to be beneficial for native plant diversity.

Human-induced versus historical habitat shifts: identifying the processes that shaped the genetic structure of the threatened grassland legless lizard, Delma impar

Historical and contemporary events are known to affect the genetic structure and diversity of species. Thus, in order to design effective conservation management strategies for threatened species, it is important to identify the processes that shaped their genetic patterns. The Striped Legless Lizard, Delma impar, is currently listed as a threatened species, and is restricted to the temperate grasslands of south eastern Australia. This habitat has undergone both historical climatic and recent anthropogenic distributional changes. We used mitochondrial DNA (mtDNA) and microsatellite markers to examine the phylogeography and population genetic structure of D. impar. Analysis of mtDNA revealed four distinct historically isolated lineages with high levels of genetic divergence that have been isolated for more than 1 million years. These lineages should be considered separate Evolutionarily Significant Units (ESU) for management purposes. Analysis of microsatellite genotypes did not reveal evidence of strong population sub-structuring despite recent anthropogenic fragmentation within the south west Victorian ESU. However, three populations were identified by the program Structure, which coincide with the transition of two regions with distinct soil and vegetation characteristics. Spatial autocorrelation analyses indicate that D. impar do not disperse long distances as they are genetically structured at distances less than 400 m.

Recovery of soil and vegetation in semi-arid Australian old fields

Due to the harsh environmental conditions of arid and semi-arid regions, recovery of native plant communities after abandonment from cultivation is hypothesised to be slow and unlikely to return to pre-disturbance condition. We examined vegetation and soil parameters along a ∼100 year chronosequence of agricultural field abandonment in semi-arid grasslands in south-eastern Australia to quantify resilience. Native species richness, abundance and composition converged towards those of uncultivated grasslands, and there was a replacement of initial exotic dominance by native perennial grasses. Thus, the vegetation did not enter an alternative stable state and the community variables studied showed some resilience. However, many native species failed to recolonise, and native species richness, composition and abundance remained significantly different from uncultivated grasslands over the span of the study. Soils demonstrated post-abandonment recovery, with differences to uncultivated grassland in most nutrients becoming non-significant by ∼50 years, and soils did not appear to be the main driver of vegetation patterns with time-since-abandonment. The basic patterns of community reassembly did not appear to be fundamentally different from temperate northern hemisphere old field succession and suggest that secondary succession in Australian semi-arid grasslands may be constrained by seed availability rather than environmental conditions.

Frequent fire promotes diversity and cover of biological soil crusts in a derived temperate grassland

The intermediate disturbance hypothesis (IDH) predicts that species diversity is maximized at moderate disturbance levels. This model is often applied to grassy ecosystems, where disturbance can be important for maintaining vascular plant composition and diversity. However, effects of disturbance type and frequency on cover and diversity of non-vascular plants comprising biological soil crusts are poorly known, despite their potentially important role in ecosystem function. We established replicated disturbance regimes of different type (fire vs. mowing) and frequency (2, 4, 8 yearly and unburnt) in a high-quality, representative Themeda australis-Poa sieberiana derived grassland in south-eastern Australia. Effects on soil crust bryophytes and lichens (hereafter cryptogams) were measured after 12 years. Consistent with expectations under IDH, cryptogam richness and abundance declined under no disturbance, likely due to competitive exclusion by vascular plants as well as high soil turnover by soil invertebrates beneath thick grass. Disturbance type was also significant, with burning enhancing richness and abundance more than mowing. Contrary to expectations, however, cryptogam richness increased most dramatically under our most frequent and recent (2 year) burning regime, even when changes in abundance were accounted for by rarefaction analysis. Thus, from the perspective of cryptogams, 2-year burning was not an adequately severe disturbance regime to reduce diversity, highlighting the difficulty associated with expression of disturbance gradients in the application of IDH. Indeed, significant correlations with grassland structure suggest that cryptogam abundance and diversity in this relatively mesic (600 mm annual rainfall) grassland is maximised by frequent fires that reduce vegetation and litter cover, providing light, open areas and stable soil surfaces for colonisation. This contrasts with detrimental effects of 2-year burning on native perennial grasses, indicating that this proliferation of cryptogams has potentially high functional significance for situations where vegetation cover is depleted, particularly for reducing soil erosion.

Effects of fire frequency and mowing on a temperate, derived grassland soil in south-eastern Australia

Frequent disturbances such as fire are widely considered important drivers of plant composition and diversity in productive grassy ecosystems. Effects of fire frequency on grassland soils, however, are less well understood. We established replicated disturbance regimes in a high-quality, representative Themeda australis–Poa sieberiana-derived grassland in south-eastern Australia that had historically been burnt every 4–8 years. Effects on soil chemical, physical and biological properties were measured after 10 years of application of 2-, 4-, and 8-yearly burning, 2-yearly mowing and an undisturbed treatment. Contrary to other grassy ecosystems, there were no detectable effects of disturbance regime on total soil nitrogen and carbon, or a range of other soil chemical properties in the top 10 cm. However, a cumulative effect of burning on the grassland soil was evident from a suite of changes to soil surface properties, available nutrients and biological activity. In particular, on biennially burnt plots, reduced litter and plant protective cover were associated with increased soil surface compaction, decreased infiltration and decreased soil biological activity, which in turn were related to poor sward recovery after fire and drought. These relationships indicate potential for positive feedbacks whereby repeated removal of soil protective cover and changes to soil surface chemistry through very frequent burning ultimately lead to further reduction in soil protective cover through reduced productivity. However, this is only likely in extreme cases: data from unburnt plots indicated that soils that had historically been burnt every 4–8 years had not passed a threshold beyond which such soil changes were irreversible or damaging. Contrary to other predictions, cessation of burning for 13 years did not lead to detectable soil nutrient release through senescence of dominant grasses. Biennial mowing with slash retention was an effective alternative disturbance for maintaining sward vigour while avoiding soil surface damage.

Aspects of the ecology of swamp antechinus (Antechinus minimus maritimus) on a Bass Strait island

The swamp antechinus (Antechinus minimus maritimus) is a small insectivorous marsupial inhabiting closed heath and tussock grassland in south-eastern Australia. The species is considered ‘Near Threatened’ on the Australian mainland. Populations persist on coastal islands off Wilsons Promontory, but their current status is unknown. This study investigated the density, diet and reproduction of the swamp antechinus on Kanowna Island. Data were collected by live trapping in different vegetation types during four trips between August 2003 and January 2004. Higher animal densities (47–129 ha–1) were found for Kanowna Island than for previously studied mainland populations (1–18 ha–1). Examination of scats showed that this species eats a wide variety of prey types, with moth larvae a major dietary component, particularly during the breeding season. Births were estimated to have occurred between 28 June and 8 August, which is a longer period than reported for other populations of this species. Factors including reduced predation, restricted dispersal and increased food availability may be responsible for supporting this dense population.

Effects of fertiliser and grazing on the arthropod communities of a native grassland in south-eastern Australia

Abstract An experiment commenced in 1998 to test the effects of superphosphate fertiliser application and grazing on production and botanical composition of a native grassland in south-eastern Australia. Superphosphate application resulted in an increase in sheep production but a decline in native perennial grasses and an increase in exotic annual grasses. The study reported here aimed to determine if arthropod assemblages showed changes in community composition on the same experimental plots. The experiment was conducted in grassland dominated by the native perennial wallaby grass, Austrodanthonia duttoniana, and consisted of six replicated treatments that were designed to improve grassland and domestic livestock productivity. Treatments consisted of a control (no fertiliser), three levels of annually applied superphosphate (62.5, 125, and 250 kg ha−1), and two treatments aimed to raise soil pH (superphosphate plus lime, and sewage ash). Soil properties were measured annually and sheep stocking rates were increased over the duration of the experiment according to increases in available forage. Soil and ground-active arthropod populations were sampled from all plots in spring 2001. Fertiliser application and grazing increased the relative abundance of introduced Acari and Collembola, and changed the community composition of Formicidae and Coleoptera. Lime and sewage treatments had variable effects on taxa. Improving the productivity of native grassland with superphosphate led to a decline in plant and arthropod biodiversity through reduced abundance and/or local extinction of native species and increased dominance of introduced species. These findings support the need to protect and restore a representative network of native grassland ecosystems within the agricultural zone of south-eastern Australia.

Perception of native grassland in southeastern Australia

Summary Native grasslands are considered to be one of Australia’s most threatened ecosystems, yet relatively little is known about human preferences and attitudes that contribute to continued degradation of these landscapes. In a study conducted in southeastern Australia, landholders were asked to assess the agricultural, ecological and aesthetic value of native grasslands and other rural landscapes depicted in colour photographs. The results confirm low preference for treeless landscapes. Landholders’ preferences for native grassland on their own property appeared most closely related to the perceived agricultural and aesthetic value of the grassland scene. This paper discusses the implication of these findings for programmes seeking to protect native grasslands on private properties.Key words environmental attitudes, native grasslands, perception.

Effects of invasion by the indigenous shrub Acacia sophorae on plant composition of coastal grasslands in south-eastern Australia

Invasion of natural ecosystems by weeds is often associated with increasing levels of disturbance. However, there is substantial evidence that cessation of disturbance can also lead to plant invasions, especially of woody species. In some coastal grasslands in south-eastern Australia, removal of grazing and burning appears to have triggered invasion by the indigenous shrub, Acacia sophorae. To quantify the impacts of such invasions on plant diversity, this study focussed on the coastal grasslands in Eurobodalla National Park, NSW. Analysis of aerial photographs indicated that 96 ha of the 479 ha study area (20%) was invaded by Acacia between 1944 and 1994, with the most rapid expansion from the late 1970s when grazing was removed. Vegetation sampling demonstrated a strong negative correlation between Acacia cover and plant species richness. A linear regression between the species richness of each quadrat and the number of growth rings on the largest Acacia branch showed an average loss of 7.5 species (38% of species) after 10 years of Acacia invasion and 15 species (76%) after 20 years. Long-term invasion favoured just a small group of shade tolerant, rhizomic grasses and sedges. Without active ecosystem management, grassland plant diversity should continue to decline and the nationally threatened herb, Thesium australe, is likely to disappear. An adaptive management program should be implemented promptly to assess the effects of different management regimes on Acacia abundance and plant diversity at ENP.

Dynamics of cryptogamic soil crusts in a derived grassland in south-eastern Australia

Dynamics of cryptogamic soil crusts in a derived grassland in south-eastern Australia

How useful are ant assemblages for monitoring habitat disturbance on grasslands in south eastern Australia

Native grasslands are one of the most endangered ecosystems in south eastern Australia. Conservation of grassland remnants and development of effective indicator groups to monitor their quality is a high priority. Recent surveys of epigaeic invertebrates have revealed several candidate groups for this. Ants are a popular focal group for invertebrate surveys in the region. The ant species richness and functional groups on four series of grassland sites in Victoria suggest that small scale heterogeneity is sufficiently high that the predictive indicator values of ants are limited, and that ants may not be sufficiently sensitive to floristic change to employ them alone in monitoring grassland condition in the region.

Defining grassland fire events and the response of perennial plants to annual fire in temperate grasslands of south-eastern Australia

Many species-rich Themeda triandra grasslands in south-eastern Australia have been burnt annually in summer as a land management practice for decades. The characteristics of annual fires (maximum surface temperatures, maximum soil temperature changes at 10 mm depth, Byram fire intensity and duration of surface heating) were compared to fires that occur less frequently (2, 4 or 7-year inter-fire interval). The impacts of annual summer fires on seed survival, perennial plant dynamics and flowering were also documented at two sites over two years.

Vegetation Changes after 10 Years of Grazing Exclusion and Intermittent Burning in a Themeda triandra (Poaceae) Grassland Reserve in South-eastern Australia

Changes in the vegetation composition of a remnant Themeda triandra Forsskal grassland in south-eastern Australia were documented following the replacement of stock grazing with intermittent burning at 3–11-year intervals. The vegetation was initially sampled in 1986, 1 year after stock were removed, and then 10 years later in 1996. Most frequently encountered grassland species were abundant in both surveys, although there was little correspondence between species richness at the quadrat scale in 1986 and 1996. Total floristic richness increased slightly over the 10-year period, owing to the proliferation of tall forbs with wind-blown seeds, including exotic thistles and colonising native forbs. Unfortunately, most native ‘increasers’ were ‘weedy’ species which are not typical or common components of species-rich temperate grassland remnants in southern Victoria. Thus, replacing grazing with intermittent burning has not resulted in the flora becoming more similar to that of high-quality, species-rich grassland remnants, but instead, has promoted a group of ruderal colonisers. The ability to identify factors contributing to particular botanical changes was hampered by the design of the management regimes implemented over the past decade. Suggestions are provided to overcome these difficulties, incorporating principles from adaptive management.

Patterns of invasion of an urban remnant of a species‐rich grassland in southeastern Australia by non‐native plant species

Abstract. The invasion by non‐native plant species of an urban remnant of a species‐rich Themeda triandra grassland in southeastern Australia was quantified and related to abiotic influences. Richness and cover of non‐native species were highest at the edges of the remnant and declined to relatively uniform levels within the remnant. Native species richness and cover were lowest at the edge adjoining a roadside but then showed little relation to distance from edge. Roadside edge quadrats were floristically distinct from most other quadrats when ordinated by Detrended Correspondence Analysis.Soil phosphorus was significantly higher at the roadside edge but did not vary within the remnant itself. All other abiotic factors measured (NH4, NO3, S, pH and % organic carbon) showed little variation across the remnant. Non‐native species richness and cover were strongly correlated with soil phosphorus levels. Native species were negatively correlated with soil phosphorus levels. Canonical Correspondence Analysis identified the perennial non‐native grasses of high biomass as species most dependent on high soil nutrient levels. Such species may be resource‐limited in undisturbed soils.Three classes of non‐native plants have invaded this species‐rich grassland: (1) generalist species (> 50 % frequency), mostly therophytes with non‐specialized habitat or germination requirements; (2) resource‐limited species comprising perennial species of high biomass that are dependent on nutrient increases and/or soil disturbances before they can invade the community and; (3) species of intermediate frequency (1–30 %), of low to high biomass potential, that appear to have non‐specialized habitat requirements but are currently limited by seed dispersal, seedling establishment or the current site management. Native species richness and cover are most negatively affected by increases in non‐native cover. Declines are largely evident once the non‐native cover exceeds 40 %.Widespread, generalist non‐native species are numerous in intact sites and will have to be considered a permanent part of the flora of remnant grasslands. Management must aim to minimize increases in cover of any non‐native species or the disturbances that favour the establishment of competitive non‐native grasses if the native grassland flora is to be conserved in small, fragmented remnants.

Importance of Canopy Gaps for Recruitment of some Forbs in Themeda triandra-dominated Grasslands in South-eastern Australia

The effect of grassland gap size on the establishment of five non-clonal perennial forbs, comprising a range of seed masses, was investigated in two Themeda triandra Forsskal grasslands by sowing seed in the centre of artificially created 6 cm (36 cm2) and 18 cm (324 cm2) wide canopy gaps. Undisturbed vegetation (0 cm gap) was used as a control. Initial seedling establishment and growth in gaps was measured over 24 weeks, as was that of transplanted juvenile plants, and all were related to light availability at ground level. The rate at which natural canopy gaps in grasslands disappear with time since burning was also quantified in a chronosequence study to infer how long gaps persist after disturbance by fire. For four of the five species, relatively few seedlings emerged (< 30% of sown seed germinated), and emergence was largely independent of the effects of gap size, sward structure and seed mass. Only Plantago gaudichaudii Barneoud germination was inhibited under a closed sward (0 cm gap). Hence, the presence of vegetation per se largely did not affect germination for most species. Survival of seedlings, however, was negatively affected by vegetation, presumably because of low light levels in the small gaps. Eryngium ovinum Cunn., P. gaudichaudii and Velleia paradoxa R.Br. failed to establish in 0 cm gaps in the 3-year-old sward. Gaps in the vegetation, however, enabled all species to survive at low levels in at least one of the grasslands, with survival of seedlings in 18 cm gaps usually greater than that in 6 cm gaps. Survival of transplants was initially high (> 50%) for all species in the 2-year-old sward, but E. ovinum and Senecio macrocarpus Belcher mortality was substantial in 0 cm gaps in the 3-year-old sward where light levels were lowest (i.e. < 9% of available light). For these species, small gaps are likely to be hostile microsites for establishment at all times. Growth was also affected by gap size, most species positively responding to 18 cm gaps by growing substantially bigger than transplants in 0 cm gaps, particularly in the more shaded 3-year-old sward gaps. The large canopy gaps (i.e. > 300 cm2) that enable the most effective recruitment in this grassland are rare in the years after fire and constitute only 8–19% of all gaps that are present at 1 and 2 years after burning. By 3 years after fire, canopy gaps are small (< 30 cm2) and infrequent (< 3 gaps m–2) as a result of rapid recovery of the dominant grass. These small gaps would appear to provide few opportunities for substantial seedling recruitment of many species by this time. If seedling recruitment events are to be optimised for the herbaceous dicotyledons that characterise this community, disturbance to the canopy is required at intervals of 1–3 years. This regime becomes particularly important when other features of the recruitment ecology of this grassland are considered.

Effects of long-term vegetation management on remnant grassy forests and anthropogenic native grasslands in south-eastern Australia

The effect of long-term vegetation management on grassy forest remnants in Gippsland, south-eastern Australia, was examined by comparing the floristic composition of rarely burnt, intermittently grazed, grassy forest remnants with frequently burnt, ungrazed sites (anthropogenic grasslands). Management history was the dominant factor controlling composition, and all frequently burnt sites supported a distinctly different flora from rarely burnt forest remnants. Frequently burnt sites contained many species that were uncommon or absent from the unburnt forest sites, and vice versa. Both vegetation types are assumed to be derived from an original grassy forest flora which contained all recorded native species. It is hypothesised that the imposition of divergent management regimes in different sites has led to an ecological segregation of native species according to their tolerance to prevailing management. The two vegetation types now make important contributions to regional diversity, thereby illustrating the need to maintain a diversity of ecosystem processes to conserve species diversity at a regional level.