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A fundamental requirement of sustainable forest management is that stands are adequately regenerated after harvesting. To date, most research has focused on the regeneration of the dominant timber species and to a lesser degree on plant communities. Few studies have explored the impact of the regeneration success of dominant tree species on plant community composition and diversity. In this study, we quantified the influence of variability in tree density and climatic and edaphic factors on plant species diversity in montane regrowth forests dominated by Eucalyptus regnans in the Central Highlands of Victoria in southeastern Australia. We found that Acacia density shaped plant biodiversity more than Eucalyptus density. Edaphic factors, particularly soil nutrition and moisture availability, played a significant role in shaping species turnover and occurrence. Our findings suggest that the density of Acacia is a key biotic filter that influences the occurrence of many understorey plant species and shapes plant community turnover. This should be considered when assessing the impacts of both natural and anthropogenic disturbances on plant biodiversity in the montane forests of southeastern Australia.

23 Pág., Purpose: Owing to their topographic location and nutrient rich soils, riparian forests are often converted to pastures for grazing. In recent decades, remnant riparian forests cleared for grazing pastures have been restored with native species. The impacts of such land-use changes on soil fungal communities are unclear, despite the central roles that soil fungi play in key ecosystem processes. We investigated how soil fungal taxonomic and functional composition are affected by land-use change at different depths, and if variation in soil fungal communities is related to edaphic properties and extant vegetation. Methods: The study was conducted in six waterways in south-eastern Australia, each comprising three land-use types: remnant riparian forest, cleared forest converted to pasture, and pastures restored with native plants. We surveyed three strata of vegetation and sampled top-soil and sub-soil to characterise physicochemical properties and soil fungal communities. ITS1 region sequences were used to assign soil fungal taxonomic and functional composition. Results: Fungal taxonomic and functional composition infrequently varied with land-use change or soil depth. Overall, environmental properties (soil and vegetation) explained 35–36% of variation in both fungal taxonomic and functional composition. Soil fungal taxonomic composition was related to soil fertility (N, P, K, pH and Ca) and ground cover characteristics, whereas functional composition was related to clay content, sub-canopy cover and tree basal area. Conclusion: Across the six studied waterways, fungal taxonomic and functional composition were more strongly associated with land-use mediated changes in site-scale soil physicochemical properties and vegetation structure than broad-scale classes of land-use type., Open Access funding enabled and organized by CAUL and its Member Institutions This study was funded by Holsworth Wildlife Research Endowment from the Ecological Society of Australia, Melbourne Water, and the Madeleine Selwyn Smith Memorial Scholarship. . Sabine Kasel is supported by the Integrated Forest Ecosystem Research Program funded by the Victorian Government Department of Environment, Land, Water and Planning. We would like to acknowledge the contributions of the Biomes of Australian Soil Environments (BASE) and Australian Microbiome consortiums for the generation of genetic data for this study. The Australian Microbiome initiative is supported by funding from Bioplatforms Australia and the Integrated Marine Observing System (IMOS) through the Australian Government’s National Collaborative Research Infrastructure Strategy (NCRIS), Parks Australia through the Bush Blitz program funded by the Australian Government and BHP, and CSIRO.

Extreme weather can have significant impacts on plant species demography; however, most studies have focused on responses to a single or small number of extreme events. Long-term patterns in climate extremes, and how they have shaped contemporary distributions, have rarely been considered or tested. BIOCLIM variables that are commonly used in correlative species distribution modelling studies cannot be used to quantify climate extremes, as they are generated using long-term averages and therefore do not describe year-to-year, temporal variability. We evaluated the response of 37 plant species to base climate (long-term means, equivalent to BIOCLIM variables), variability (standard deviations) and extremes of varying return intervals (defined using quantiles) based on historical observations. These variables were generated using fine-grain (approx. 250 m), time-series temperature and precipitation data for the hottest, coldest and driest months over 39 years. Extremes provided significant additive improvements in model performance compared to base climate alone and were more consistent than variability across all species. Models that included extremes frequently showed notably different mapped predictions relative to those using base climate alone, despite often small differences in statistical performance as measured as a summary across sites. These differences in spatial patterns were most pronounced at the predicted range margins, and reflect the influence of coastal proximity, continentality, topography and orographic barriers on climate extremes. Species occupying hotter and drier locations that are exposed to severe maximum temperature extremes were associated with better predictive performance when modelled using extremes. Understanding how plant species have historically responded to climate extremes may provide valuable insights into our understanding of contemporary distributions and help to make more accurate predictions under a changing climate.

Aim: Forest carbon storage is the result of a multitude of interactions among biotic and abiotic factors. Our aim was to use an integrative approach to elucidate mechanistic relationships of carbon storage with biotic and abiotic factors in the natural forests of temperate Australia, a region that has been overlooked in global analyses of carbon-biodiversity relations. Location: South-eastern Australia. Time period: 2010–2015. Major taxa studied: Forest trees in 732 plots. Methods: We used the most comprehensive forest inventory database available for south-eastern Australia and structural equation models to assess carbon-storage relationships with biotic factors (species or functional diversity, community-weighted mean (CWM) trait values, structural diversity) and abiotic factors (climate, soil, fire history). To assess the consistency of relationships at different environmental scales, our analyses involved three levels of data aggregation: six forest types, two forest groups (representing different growth environments), and all forests combined. Results: Structural diversity was consistently the strongest independent predictor of carbon storage at all levels of data aggregation, whereas relationships with species- and functional-diversity indices were comparatively weak. CWMs of maximum height and wood density were also significant independent predictors of carbon storage in most cases. In comparison, climate, soil, and fire history had only minor and mainly indirect effects via biotic factors on carbon storage. Main conclusions: Our results indicate that carbon storage in our temperate forests was underpinned by tree structural diversity (representing efficient utilisation of space) and by CWM trait values (representing selection effects) more so than by tree species richness or functional diversity. Abiotic effects were comparatively weak and mostly indirect via biotic factors irrespective of the environmental range. Our study highlights the importance of managing forests for functionally important species and to maintain and enhance their structural complexity in order to support carbon storage.

We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge., Measurement(s)plant traitTechnology Type(s)digital curationSample Characteristic - OrganismViridiplantaeSample Characteristic - LocationAustralia Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14545755

In this study, we examined the associations between field-assessed floristic and structural habitat values for mature forest and GIS-derived variables to assess whether high conservation value forests could be predicted for strategic reservation at a landscape scale. We investigated the Eucalyptus regnans forests of the Victorian Central Highlands in south-eastern Australia, where several extensive wildfires in the last century have left little mature forest. We assessed the extent to which the floristic composition and a suite of habitat-related structural variables could be explained by two forest inventory GIS variables (percentage senescence and site productivity) and whether explanatory capacity improved from inclusion of additional environmental variables (climate, soils, topography, structure and spatial location). Results showed that the floristic composition was weakly related to productivity, but not to percentage senescence. Four habitat-related structural variables were positively related to percentage senescence (density of old-growth eucalypts, the quadratic mean diameter (QMD) of both live and dead eucalypts, and the maximum eucalypt form class (a proxy for tree hollows)) while the volume of CWD had a marginally significant positive relationship. Three structural variables were related to productivity (the maximum eucalypt form class, the QMD of dead understorey trees and of dead eucalypts). However, in all cases the explanatory power of percentage senescence and productivity was weak (proportion of deviance explained by the models

14 Pág. Departamento de Medio Ambiente y Agronomía​, Dead wood, including dead standing trees (DST) and coarse woody debris (CWD), is a critical component of forest ecosystems that provides habitat and refugia for fauna, flora, and microbial communities and plays a key role in carbon and nutrient cycling. However, few studies have modelled the long-term dynamics of dead wood, limiting our ability to predict how the abundance and composition of dead wood may change with climate change or altered fire regimes. Here we analyse DST and CWD data in 884 plots encompassing multiple field campaigns and forest types of varying canopy cover and species composition across the State of Victoria in temperate south-eastern Australia. We use boosted regression tree modelling to examine the relative influence of disturbance history and tree functional traits on dead wood biomass while accounting for the influence of environmental and climatic factors and stand attributes across a broad productivity gradient. We modelled absolute and relative dead wood biomass by size (‘small’ 100 < 200 mm diameter, ‘medium’ 200 < 500 mm diameter, ‘large’ ≥ 500 mm diameter) and decay classes (sound to advanced decay) to evaluate the consistency of predictor effects among different components of dead wood. We found that live tree basal area and mean annual precipitation were influential predictors of both DST and CWD biomass, indicating an over-arching effect of forest productivity on dead wood biomass. Fire history was also an important predictor, with DST biomass decreasing and CWD biomass increasing with time since last wildfire. The proportion of large DST biomass increased with increased tree mortality as a result of fire interval and time in drought. DST biomass also increased and CWD biomass decreased with increasing wood density, and this was relatively more important than the other functional traits we examined (heartwood nitrogen content and bark type). Our study suggests that forest productivity, fire history, drought and wood density are important determinants of dead wood, as they influence dead wood inputs and outputs. Our study reveals the broad-scale drivers of dead wood biomass, and the potential for altered fire regimes and changing climate to influence live- to dead wood dynamics and associated ecosystem functions., This research was undertaken with approval by the Victorian Department of Environmental, Land, Water and Planning (DELWP) under Research Permit Numbers 10006440, 10006488, 10006691, 10007105, and the Forests Act 1958 (FS/14/3694/1/3). The work was funded by the Victorian DELWP through the Integrated Forest Ecosystem Research Program, with additional support from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) former Sustainable Agriculture Flagship program. For their contributions to data collection, we thank: Helen Vickers, Julio Najera-Umana and Benjamin Smith from The University of Melbourne, Australia; Michele Kohout, Matthew Bruce, and colleagues from Arthur Rylah Institute for Environmental Research, Australia; Elizabeth Pryde and colleagues from Arthur Rylah Institute for Environmental Research, Australia; and Sue Baker from the University of Tasmania, Australia. The study benefited from the TRY database on plant traits (http://www.try.db.org), which is hosted, developed and maintained by J. Kattge and G. Bönisch (Max Planck Institute for Biogeochemistry, Jena, Germany). TRY is currently supported by DIVERSITAS/Future Earth and the German Centre for Integrative Biodiversity Research (iDiv).

Tree ferns are slow-growing and long-lived components of temperate forests; however, these characteristics make determining size-age and population dynamics through mensuration approaches problematic while dendroecological approaches cannot be used. In this study, we use radiocarbon (14C) dating of Cyathea australis and Dicksonia antarctica to (1) determine their age-to-size relationships, (2) reconstruct the age distribution of tree fern species, and (3) test if predicted ages align with the ages of the co-occurring tree community and observed disturbance history. We used the best age-size models to reconstruct the population structure of tree ferns sampled in five paired rainforest and old-growth eucalypt stands and compared these to the age structure of co-occurring tree species. The species had similar growth allometry; however, C. australis grew four times faster than D. antarctica. The age class structures of tree ferns were congruent with the associated tree species and reflected known fire history and snowfall events in the region. Tree fern abundance increased with increasing time-since-fire and post canopy disturbance. The study demonstrates that 14C dating of tree ferns provides a means of investigating tree fern demographics and the role of disturbance in shaping their population structure in forests of southeast Australia.

In the forested landscapes of southeastern Australia, bushfires and timber harvesting are the primary catalysts for regeneration in Eucalyptus regnans, E. delegatensis, and high elevation mixed species (HEMS) forests. Quantifying the role of climate, topography and edaphic conditions on plant regeneration is important for understanding current and future risks of climate change. In this study, we investigated the post-disturbance regeneration dynamics in these forests. We sought to determine the direct impact of climate variability on regeneration and the interactive effects of climate, topography, and edaphic factors on the regeneration success of Eucalyptus. Data was collated from regeneration surveys conducted in 881 coupes, totaling ~55,000 ha of forest harvested and regenerated between 2004 and 2012. The time-period analyzed included the Millennium Drought, an intense and prolonged drought that lasted from 1996 to 2010. To test the influence of climatic, topographic, and edaphic variables on the occurrence and abundance of Eucalyptus regeneration, we used machine learning models. We found that regeneration success was closely tied to the timing of the Millennium Drought. Between 2004 and 2005 Eucalyptus seedlings occurred in less than 50% of survey plots across all three forest types. Declines in regeneration during the period of drought were greater in E. regnans and E. delegatensis than HEMS forests, suggesting that regeneration in the HEMS forests is more resistant to drought. We found that seasonal precipitation and temperature had the greatest influence on regeneration success of Eucalyptus. Responses varied by species, however autumn precipitation had the strongest influence on abundance of regeneration of E. regnans and E. delegatensis, while summer temperature was more important for HEMS species. Our findings highlight the importance of seasonal and annual climate variability on Eucalyptus regeneration and portend potential declines in regeneration success in a warmer and drier future for E. regnans and E. delegatensis.

Australia’s temperate forest landscapes encompass broad topographic and edaphic ranges, and are regularly disturbed by fire. Nonetheless, relative contributions of environmental heterogeneity, disturbance regimes, and dispersal limitations to plant species turnover remain poorly understood. To evaluate the relative influences of deterministic (environmental, disturbance), and stochastic (spatial) processes on plant species turnover [beta-diversity (β diversity)] in natural forest landscapes, and how such influences vary among plant functional types and vegetation strata. We assessed the environment and species composition of 81 forest stands, representing a range of structures and fire histories across contiguous landscapes in south-eastern Australia, and examined the potential to explain β diversity using variance partitioning and distance-decay analyses. Explanatory variables accounted for 34–55% of β diversity of multiple plant functional types, with environmental heterogeneity explaining the greatest proportion (10–25%). Stand structural variables (e.g., leaf area index, height coefficient of variation) accounted for 8–14% of β diversity in understorey life forms and 5% in canopy species, far greater than a single direct descriptor of disturbance history such as time-since-fire which explained just 2% of tree and shrub β diversity. β Diversity increased with increasing geographic distance for all functional types. Dispersal limitation accounted for 5–11% of β diversity, and distance-decay rates varied among plant functional types. Landscape-scale conservation of forest biodiversity will require representation of a broad environmental range as well as metrics that fully capture site disturbance histories, including stand structural complexity as a potential proxy for fire regimes.

In southeast Australia, fire regimes are changing. Conserving species into the future under these changing fire regimes will require understanding their recruitment and growth dynamics following historical fires. Where monitoring is absent, dendroecology provides a tool for reconstructing and quantifying these dynamics. The use of dendroecology in southeast Australia has been limited due to presumptions that many of the species do not produce annual growth rings. In this study, we determined the dendroecological potential of a fire-sensitive understorey tree species, Pomaderris aspera, as a case study species, to explore the potential to use of understorey species to provide insights into past fire history. We used growth patterns of this species to understand the role of resource limitation on growth and senescence. We found that P. aspera had distinct growth rings and high within tree correlation when cross-dated. Recruitment events of this species aligned with three known fire events. We found that the impacts of historical fire on tree canopy cover could be estimated. P. aspera grew rapidly post fire and then become suppressed within 9–15 years. Cycles of growth release and suppression were found with increasing incidence of suppression occurring over time. Increased suppression and reduced growth rates aligned with patterns of recorded senescence over time in the understories of a maturing. Eucalyptus canopy. Our results highlight the potential to use dendroecology to confirm past fire extents and amount of canopy disturbances and the impacts that these events have on the recruitment and growth dynamics of understorey species in southeast Australia.

Departamento de Medio Ambiente y Agronomía​ (INIA), Riparian forests were frequently cleared and converted to agricultural pastures, but in recent times these pastures are often revegetated in an effort to return riparian forest structure and function. We tested if there is a change in the soil bacterial taxonomy and function in areas of riparian forest cleared for agricultural pasture then revegetated, and if soil bacterial taxonomy and function is related to vegetation and soil physicochemical properties. The study was conducted in six riparian areas in south‐eastern Australia, each comprising of three land‐use types: remnant riparian forest, cleared forest converted to pasture, and revegetated pastures. We surveyed three strata of vegetation and sampled surface soil and subsoil to characterize physicochemical properties. Taxonomic and functional composition of soil bacterial communities were assessed using 16S rRNA gene sequences and community level physiological profiles, respectively. Few soil physiochemical properties differed with land use despite distinct vegetation in pasture relative to remnant and revegetated areas. Overall bacterial taxonomic and functional composition of remnant forest and revegetated soils were distinct from pasture soil. Land‐use differences were not consistent for all bacterial phyla, as Acidobacteria were more abundant in remnant soils; conversely, Actinobacteria were more abundant in pasture soils. Overall, bacterial metabolic activity and soil carbon and nitrogen content decreased with soil depth, while bacterial metabolic diversity and evenness increased with soil depth. Soil bacterial taxonomic composition was related to soil texture and soil fertility, but functional composition was only related to soil texture. Our results suggest that the conversion of riparian forests to pasture is associated with significant changes in the soil bacterial community, and that revegetation contributes to reversing such changes. Nevertheless, the observed changes in bacterial community composition (taxonomic and functional) were not directly related to changes in vegetation but were more closely related to soil attributes., This research was funded by Holsworth Wildlife Research Endowment from the Ecological Society of Australia, Melbourne Water, and the Madeleine Selwyn Smith Memorial Scholarship. Vicky Waymouth was a recipient of a Research Training Program Scholarship. Cybec Foundation supported Rebecca Miller during her lectureship at Melbourne University. We would like to acknowledge the contributions of the Biomes of Australian Soil Environments (BASE) and Australian Microbiome consortiums to the generation of genetic data for this study. The Australian Microbiome initiative is supported by funding from Bioplatforms Australia and the Integrated Marine Observing System (IMOS) through the Australian Government’s National Collaborative Research Infrastructure Strategy (NCRIS), Parks Australia through the Bush Blitz program funded by the Australian Government and BHP, and CSIRO. Soil collection and field sampling was conducted under Parks Victoria permit number 10008494., 24 Pág. This article belongs to the Special Issue Restoring Forest Landscapes: Impact on Soil Properties and Functions

Soil organic carbon (SOC) stocks in Australia’s temperate forests have been overlooked in national soil databases and in global SOC analyses of natural ecosystems despite the importance of temperate forests to the global terrestrial carbon balance. This limits the potential to both predict change in SOC stocks in temperate Australia and to identify where and how SOC stocks can be managed to mitigate climate change. Based on data from 707 sites, we examine variations in SOC concentrations and stocks across a range of natural temperate broadleaf forests in south-eastern Australia. Comparisons with current Australia-wide databases highlight previous under-estimation of forest SOC concentrations, leading to substantial underprediction of SOC stocks in the most productive forests (e.g. this study’s mean of 207 Mg C ha−1 compared with a database mean estimate of 141 Mg C ha−1 for Tall open-forests to 30-cm soil depth). Random Forest models involving 27 environmental variables (representing climate, terrain, parent material, soil attributes, vegetation, and fire history) explained up to 79% of the variation in SOC concentrations and 77% of the variation in SOC stocks to 30-cm depth. Climate variables (precipitation, temperature) were of greatest importance to the prediction of both SOC concentrations and SOC stocks, tending to override the importance of terrain and fire-history variables at this study’s regional scale. While patterns in SOC concentrations and stocks were correlated, SOC concentrations were not a reliable proxy for SOC stocks to 10-cm depth, reiterating the importance of mass equivalent measures (i.e. soil bulk density) to assessing changes in soil carbon storage. Our study provides a timely check of the model-based estimates of SOC concentrations and stocks in Australia’s temperate forests that are currently available in nation-wide databases and improves the available information for defining benchmarks, and for identifying potential areas of SOC loss and gain, in programs that aim to mitigate climate change.

Non-structural carbohydrates (NSCs) are crucial to support tree resprouting after disturbances that damage the crown or stem. Epicormic resprouting (from stem) could demand more from NSC reserves than basal resprouting (following top-kill), since epicormically resprouting trees need to maintain a greater living biomass. Yet, little is known about NSC use during epicormic resprouting, particularly the relative importance of stem and below-ground NSC reserves. We compared the distribution and magnitude of NSC decreases during epicormic and basal resprouting by experimentally removing crowns or stems of 14-year-old Eucalyptus obliqua L'Her. trees in native forest, then harvesting these trees over a 10-month period (start, sprouts emerged, sprouts expanded) to measure changes in NSC concentration and mass by organ (stem, lignotuber, roots). We hypothesized that (i) NSC depletion during resprouting is primarily due to decreases in starch rather than soluble sugars concentrations; (ii) during epicormic resprouting, stem NSC concentrations are decreased irrespective of any decreases in roots; and (iii) absolute decreases in NSC mass are greater for epicormic than basal resprouting during the leafless period due to the carbon demands associated with maintaining greater living biomass. Results confirmed our hypotheses; starch was the primary storage carbohydrate, stems were an important source of starch during epicormic resprouting and carbon demands of maintenance functions were greater for epicormic resprouting, leading to greater decreases in NSC reserves. Roots were a more important starch storage organ than the lignotuber for both epicormic and basal resprouting. The proportional decrease in starch was severe for both modes of resprouting due to a long leafless period, after which trees resprouting epicormically relied on starch reserves for longer than those resprouting basally. It remains to be seen how the timing of disturbance affects the timing and vigour of resprouting, and how long-term NSC recovery differs for epicormic and basal resprouting.

Flowering phenology plays an important role in the plant life cycle as it is sensitive to climate. The timing and intensity of flowering is important for the reproductive success, fitness, survival and diversity of plants. Its study in relation to the environment can therefore aid in understanding the response of species to climate change. Long-term studies examining the relationship between flowering phenology and climate are limited in Australia. This study explores the effect of photoperiod length, temperature and rainfall on flowering duration and intensity of Eucalyptus tricarpa, Eucalyptus microcarpa and Eucalyptus polyanthemos using long term data sets from two locations and the statistical model: generalised additive model for location, scale and shape (GAMLSS). The study further incorporates the phenological response to calibrate the flowering sub-module of the mechanistic model TACA-GEM to investigate the effect of predicted climate change on flowering phenology. Flowering intensity of E. microcarpa increased as temperatures warmed in the months prior to flowering but declined when warmer temperatures occurred in the early stages of bud development. For E. polyanthemos flowering decreased with increases in temperature combined with decreased rainfall and shorter days. Increased rainfall, cooler temperatures and shorter days increased flowering in E. tricarpa. Modelling of species response to climate change showed that decreases in flowering intensity and duration for all three species are likely. The temperature thresholds required for flowering of E. polyanthemos were exceeded under climate change while the requirement for longer days prevented flowering phenology shifting to cooler months. E. tricarpa exhibited a decline in flowering intensity and duration under climate change; however, its requirements for shorter days allowed the species to continue to flower during winter. E. microcarpa displayed no consistent relationship to photoperiod and a decline in flowering intensity and duration under climate change was modelled. The species’ specific responses to photoperiod suggests that flowering asynchrony between the coexisting species may be linked to day length and that the asynchrony will be strengthened under climate change as flowering duration and intensity contract under a warmer and drier climate.

This study investigates whether undertaking a rotation of pine plantation on abandoned farmland facilitates the return of native species. Plant functional traits were used as a means of assessing the effects of land-use change on vegetation. We explored the relationships among plant traits, time since harvesting and environmental variables for the vegetation found in Pinus radiata plantations after clear-felling. Vegetation was monitored 1-3. years following harvesting and repeated eight years later. We compared species richness, composition and traits to those in reference native forest and abandoned farmland. There was a significant temporal shift in attribute associations of harvested plantations towards those in native forest and a move away from plant attributes common to the pre-plantation use of abandoned farmland. Cluster analysis produced ten emergent groups of plant functional traits for 144 plant species. After harvesting, attribute associations were typical of therophytes and included high specific leaf area (SLA), small stature, arbuscular or non-mycorrhizal associations and small, wind-dispersed seed. These were predominantly introduced species that were dominant in abandoned farmland. The repeat survey identified an obvious decrease in therophytes and an increase in species with low SLA, ant dispersal, large seed and ectomycorrhizal associations. This was largely due to an increase in native Myrmecochorous shrubs. Similar attributes were also shared by Ericoid heaths but these species failed to recolonise harvested sites. Relationships among plant traits of species and environmental variables changed over time with a greater proportion of the variance in attribute associations explained by prevailing site conditions (e.g. type of ground cover, edaphic properties) with increasing time since harvesting. There were no relationships among plant attribute associations and stem density or basal area of planted overstorey species suggesting that planting of tubestock seedlings of native overstorey species does not effectively promote the development of native vegetation. The persistence of introduced grasses in areas of former plantation, recruitment failure of native species and a ready supply of introduced species from surrounding land uses suggest that additional rehabilitation measures will be required to promote the return of a fuller complement of native species.

Non-structural carbohydrates (NSCs) form a fundamental yet poorly quantified carbon pool in trees. Studies of NSC seasonality in forest trees have seldom measured whole-tree NSC stocks and allocation among organs, and are not representative of all tree functional types. Non-structural carbohydrate research has primarily focussed on broadleaf deciduous and coniferous evergreen trees with distinct growing seasons, while broadleaf evergreen trees remain under-studied despite their different growth phenology. We measured whole-tree NSC allocation and temporal variation in Eucalyptus obliqua L'Her., a broadleaf evergreen tree species typically occurring in mixed-age temperate forests, which has year-round growth and the capacity to resprout after fire. Our overarching objective was to improve the empirical basis for understanding the functional importance of NSC allocation and stock changes at the tree- and organ-level in this tree functional type. Starch was the principal storage carbohydrate and was primarily stored in the stem and roots of young (14-year-old) trees rather than the lignotuber, which did not appear to be a specialized starch storage organ. Whole-tree NSC stocks were depleted during spring and summer due to significant decreases in starch mass in the roots and stem, seemingly to support root and crown growth but potentially exacerbated by water stress in summer. Seasonality of stem NSCs differed between young and mature trees, and was not synchronized with stem basal area increments in mature trees. Our results suggest that the relative magnitude of seasonal NSC stock changes could vary with tree growth stage, and that the main drivers of NSC fluctuations in broadleaf evergreen trees in temperate biomes could be periodic disturbances such as summer drought and fire, rather than growth phenology. These results have implications for understanding post-fire tree recovery via resprouting, and for incorporating NSC pools into carbon models of mixed-age forests.

Reducing uncertainty in forest carbon estimates at local and regional scales has become increasingly important due to the centrality of the terrestrial carbon cycle in issues of climate change. Despite relatively limited geographical extent, temperate forests are among the most carbon dense forests in the world. Estimates of carbon in key understorey life forms and belowground components of these forests have often been excluded from previous studies in south-eastern Australia. We estimated above- and belowground carbon stocks (including soil to 0.3 m depth) in stands of cool temperate rainforest (‘rainforest’), wet sclerophyll forest (‘eucalypt forest’), and mixed rainforest–wet sclerophyll stands (‘ecotone forest’) across a wide range of environmental conditions and forest structures. We examined relationships among component carbon stocks and a range of environmental variables (edaphic, climatic, spatial) and present the first allometric equations and carbon stock estimates for south-eastern Australian tree ferns. Component carbon stocks were within the range of published values for these stand types. Using multivariate analyses of all component stocks, we detected significantly more carbon in total above- and belowground components in ecotone (697 Mg ha −1 , 95% confidence interval 575–819 Mg ha −1 ) and eucalypt forests (689 Mg ha −1 , 605–773 Mg ha −1 ) than rainforest (550 Mg ha −1 , 453–647 Mg ha −1 ). However, we found no significant differences among the stand types in the proportional distribution of carbon among components despite significant differences in structural composition as indicated by size class distributions of the main genera. Of total carbon, ∼48% was stored in trees (>2 cm over-bark diameter), and ∼72% of tree carbon was stored in the largest 10% of all trees. The most important environmental variables associated with carbon stocks irrespective of stand type were edaphic variables, most commonly total and available soil nitrogen. Tree fern carbon was the only component stock more strongly associated with climatic and spatial than edaphic variables. Our findings indicate that disturbance mediated changes in stand dynamics could significantly alter total carbon stocks, particularly if more frequent fires limit tree recruitment and increase large tree mortality. Monitoring of these forests for carbon could place greater emphasis on key structural elements associated with the largest proportion of total carbon, the largest trees. By reducing uncertainties associated with estimates of carbon in key stocks, we can better understand potential future changes to the carbon cycle from altered stand dynamics under climate change.

Human-induced changes in the natural environment are affecting the provision of ecosystem goods and services (EGS). Land use plans rarely include the value of public ecosystem services such as climate regulation and biodiversity due to difficulties in valuing these services. In this study, we assessed total economic value for five important ecosystem goods and services under five future land-use scenarios using varying levels of costs, prices and discount rates. Results indicated that at higher discount rates normally applied to commercial activities, and assuming the current prices for goods and services, net present value (NPV) was highest for landscape management scenarios aimed at maximising agricultural production. Potential income from services such as carbon and biodiversity does not offset projected income lost from agriculture due to land-use changes. At higher discount rates, NPV was negative for the two scenarios aimed at enhancing the longer term ecological sustainability of the landscape. These results indicate that income from carbon sequestration and biodiversity conservation would need to be considerably higher than current levels in order to justify focusing management of this landscape on ecological outcomes. At lower discount rates (at levels normally associated with public investments), the more ecologically appropriate ‘mosaic farming system’ had the highest NPV, indicating that this type of system might be attractive for investors interested in longer term return horizons or wider public benefits. Higher income from carbon or biodiversity, or increased return from timber by using high value tree species, could potentially make more ecologically appropriate systems profitable at higher discount rates.

The significance of waste-stabilisation ponds (WSPs) to waterbirds has been well documented, but WSP differ depending on their place and purpose in the sewage-treatment system, and there is little ...

Human impacts on the natural environment have resulted in a steady decline in biodiversity and associated ecosystem services. A major policy and management challenge is to efficiently allocate limited resources for nature conservation to maximise biodiversity benefits. Spatial assessment and mapping of biodiversity value plays a vital role in identifying key areas for conservation and establishing conservation priorities. This study measured biodiversity value using readily available data and tools in order to identify conservation priority sites in a heavily modified and fragmented production landscape. The study also assessed trade-offs among biodiversity and other ecosystem services. We used spatial tools for assessing and mapping biodiversity such as Patch Analyst in ArcGIS 10.2 to assess landscape alteration states, and the Integrated Valuation of Ecosystem Services and Tradeoffs to identify habitat quality. Results indicated that areas of high biodiversity conservation value were concentrated in less modified land-cover types. Substantially modified land-cover types (generally associated with agriculture and irrigated pastures) had lower habitat quality and biodiversity value. The analysis revealed that assessments based solely on habitat condition may not be the most suitable basis for conservation planning because this does not include associated adjacent land uses, roads or other threats to biodiversity. Spatially targeted environmental plantings and less intensive agroforestry that reconnect native remnants in heavily fragmented landscapes can provide significant potential conservation outcomes. Planned landscape reconfiguration based on readily available spatial data can yield net positive benefits to biodiversity by halting degradation of remnant native vegetation and increasing total habitat area.

Growth is one of the most important phenological cycles in a plant's life. Higher growth rates increase the competitive ability, survival and recruitment and can provide a measure of a plant's adaptive capacity to climate variability and change. This study identified the growth relationship of six Eucalyptus species to variations in temperature, soil moisture availability, photoperiod length and air humidity over 12 months. The six species represent two naturally co-occurring groups of three species each representing warm-dry and the cool-moist sclerophyll forests, respectively. Warm-dry eucalypts were found to be more tolerant of higher temperatures and lower air humidity than the cool-moist eucalypts. Within groups, species-specific responses were detected with Eucalyptus microcarpa having the widest phenological niche of the warm-dry species, exhibiting greater resistance to high temperature and lower air humidity. Temperature dependent photoperiodic responses were exhibited by all the species except Eucalyptus tricarpa and Eucalyptus sieberi, which were able to maintain growth as photoperiod shortened but temperature requirements were fulfilled. Eucalyptus obliqua exhibited a flexible growth rate and tolerance to moisture limitation which enables it to maintain its growth rate as water availability changes. The wider temperature niche exhibited by E. sieberi compared with E. obliqua and Eucalyptus radiata may improve its competitive ability over these species where winters are warm and moisture does not limit growth. With climate change expected to result in warmer and drier conditions in south-east Australia, the findings of this study suggest all cool-moist species will likely suffer negative effects on growth while the warm-dry species may still maintain current growth rates. Our findings highlight that climate driven shifts in growth phenology will likely occur as climate changes and this may facilitate changes in tree communities by altering inter-specific competition.

This paper reviews approaches to measuring and managing the multiple ecosystem goods and services (ESS) provided by production landscapes. A synthesis of these approaches was used to analyse changes in supply of ESS in heavily cleared and fragmented production landscapes in south-east Australia. This included analysis of spatial and temporal trade-offs and synergies among multiple ESS. Spatially explicit, up-to-date and reliable information can be used to assess ESS supplied from different types of land uses and land cover and from different parts of a landscape. This can support effective management and payment systems for ESS in production landscapes.

With the loss of natural wetlands, artificial wetlands are becoming increasingly important as habitat for waterbirds. We investigated the relationships between waterbirds and various biophysical parameters on artificial wetlands in an Australian urban valley. The densities (birds per hectare) of several species were correlated (mostly positively) with wetland area, and correlations were observed between certain species and other physical and water chemistry variables. Waterbird community structure, based on both abundance (birds per wetland) and density data, was most consistently positively correlated with the relative amount of wetland perimeter that was vegetated, surface area, distance to nearest wetland, public accessibility and shoreline irregularity. We also compared the relative use of the two types of urban wetlands, namely urban lakes and stormwater treatment wetlands, and found for both abundance and density that the number of individuals and species did not vary significantly between wetland types but that significant differences were observed for particular species and feeding guilds, with no species or guild being more abundant or found in greater density on an urban lake than a stormwater treatment wetland. Designing wetlands to provide a diversity of habitat will benefit most species.

Many production landscapes are complex human-environment systems operating at various spatio-temporal scales and provide a variety of ecosystem goods and services (EGS) vital to human well-being. EGS change over space and time as a result of changing patterns of land use or changes in the composition and structure of different vegetation types. Spatio-temporal assessment of EGS can provide valuable information on the consequences of changing land use and land cover for EGS and helps to deal with this complexity. We carried out a quantitative and qualitative appraisal of selected EGS (timber production, carbon stock, provision of water, water regulation, biodiversity, and forage production) to understand how these have altered in a complex mosaic of landscape that has undergone significant change over the past 200 years. Land use and land cover types and their associated EGS were assessed and mapped using a wide range of readily available data and tools. We also evaluated the trade-offs among services associated with observed land use change. In contrast to work elsewhere, we found the recent changes in land use and land cover have an overall positive impact on various EGS due mainly to the conversion of pasture to managed plantations which are connected to the larger areas of remnant vegetation. Results also indicate that there was a high level of variation in the distribution of the EGS across the landscape. Relatively intact native vegetation provides mainly regulating services whereas the modified landscapes provides provisioning services such as timber and forage production at the cost of regulating services. Rapidly changing demand and supply of certain goods and services (e.g., timber, pulp or carbon) may also have positive and negative impact on other services. For example, increasing plantation rotation has positive impacts for biodiversity and carbon stock but reduces stream flow and water yield.

Understanding the roles of different types of natural and artificial wetlands in providing habitat for waterbirds is crucial to active interventions to conserve wetland biodiversity. This study made use of a large database compiled over 22 years from the ‘Summer Waterfowl Count’ to determine the relative use of five wetland types by 18 species of waterfowl in Victoria, south-eastern Australia. The abundance of 14 species and density of 15 differed significantly (P

While edge effects on tree water relations are well described for closed forests, they remain under-examined in more open forest types. Similarly, there has been minimal evaluation of the effects of contrasting land uses on the water relations of open forest types in highly fragmented landscapes. We examined edge effects on the water relations and gas exchange of a dominant tree (Eucalyptus arenacea Marginson & Ladiges) in an open forest type (temperate woodland) of south-eastern Australia. Edge effects in replicate woodlands adjoined by cleared agricultural land (pasture edges) were compared with those adjoined by 7- to 9-year-old eucalypt plantation with a 25m fire break (plantation edges). Consistent with studies in closed forest types, edge effects were pronounced at pasture edges where photosynthesis, transpiration and stomatal conductance were greater for edge trees than interior trees (75m into woodlands), and were related to greater light availability and significantly higher branch water potentials at woodland edges than interiors. Nonetheless, gas exchange values were only ∼50% greater for edge than interior trees, compared with ∼200% previously found in closed forest types. In contrast to woodlands adjoined by pasture, gas exchange in winter was significantly lower for edge than interior trees in woodlands adjoined by plantations, consistent with shading and buffering effects of plantations on edge microclimate. Plantation edge effects were less pronounced in summer, although higher water use efficiency of edge than interior woodland trees indicated possible competition for water between plantation trees and woodland edge trees in the drier months (an effect that might have been more pronounced were there no firebreak between the two land uses). Scaling up of leaf-level water relations to stand transpiration using a Jarvis-type phenomenological model indicated similar differences between edge types. That is, transpiration was greater at pasture than plantation edges in summer months (most likely due to greater water availability at pasture edges), resulting in significantly greater estimates of annual transpiration at pasture than plantation edges (430 vs. 343lm(-2)year(-1), respectively). Our study highlights the need for landscape-level water flux models to account for edge effects on stand transpiration, particularly in highly fragmented landscapes.

We examined the potential role of the soil seed bank in restoration of an open eucalypt forest community following land-use change involving clearing of native eucalypt forest for grazing and subsequent abandonment, and for establishment of Pinus radiata plantation. We used plant functional traits responsive to disturbance and other traits associated with the capacity to re-colonise and form persistent seed banks as a means of assessing the effects of land-use change on soil seed banks. The soil seed bank and corresponding extant vegetation was surveyed within four replicated paired sites of fragmented native forest and abandoned farmland, and native forest and pine plantation. There was a significant difference in the composition of the soil seed bank for both land-use changes. Non-metric Multi-dimensional Scaling of plant attributes showed a clear separation of samples according to land-use type and between seed bank and extant vegetation. Cluster analysis of plant functional traits produced eight emergent groups. Phanerophytes were classified as either Ant-dispersed shrubs and herbs, Ericoid heaths or Eucalypts, perennial herbs were either Vertebrate-dispersed species, Barochorous annuals and herbs or Small-seeded hemicryptophytes and the remaining species were Wind-dispersed species or Small-seeded annuals. Small-seeded annuals dominated the soil seed banks and native phanerophytes with low specific leaf area, resprouting, ant-dispersal, large seed, and ericoid mycorrhizal and ectomycorrhizal associations formed a minor component of the soil seed bank for all land-use types. Sorensen Similarity between the vegetation and soil seed bank was low across all land-use types and was explained by the dominance of annuals in the soil seed bank and perennial species in the extant vegetation. Indicator species analysis revealed an increase in Wind-dispersed species, Barochorous species and Small-seeded annuals in the soil seed bank relative to extant vegetation. Trait associations include a therophyte life form (of predominantly introduced species) with high specific leaf area, small round seed, a seeder fire response, and arbuscular or non-mycorrhizal associations. Underlying axes in trait variation indicate seed banks were dominated by traits associated with the rapid acquisition of resources or the ability to respond rapidly to disturbance that provided for large and persistent stores of introduced ruderal species. In contrast, species excluded from the seed bank shared traits associated with the conservation of resources or ability to withstand environmental stress and were typical of native phanerophytes. These generalisable patterns in plant traits make it unlikely that eucalypt communities can be restored from the native soil seed bank alone.

Plantings of diverse native tree species aim to reverse negative effects of widespread vegetation clearing in temperate Australia. Studies of the environmental outcomes of these biodiverse plantings currently provide little information on carbon sequestration, which could limit their integration into emerging carbon markets. This paper presents soil organic carbon (SOC) data from four biodiverse native plantings at age 9 to 17 years across north-central Victoria in south-eastern Australia. Effects of site and tree species on SOC (0–10 cm depth) were examined using soils from under four species common to all plantings ( Acacia implexa , Acacia mearnsii , Allocasuarina verticillata and Eucalyptus melliodora ) that were analysed for aggregate stability, and for SOC and δ 13 C in whole soil and in aggregate fractions. Tree establishment had no effect on soil aggregate stability despite significant effects on SOC. Weak associations between aggregation and SOC concentrations were presumably partly due to the clay mineralogy of the study soils, in which aggregate formation is more dependent on electrostatic bridging between 1:1 clay particles than on organic matter. This influence of clay mineralogy might also partly explain poor correlations between SOC and clay content across sites. Contrary to findings elsewhere of decreases in SOC to about 30 years after afforestation, effects of tree establishment on SOC in this study ranged from negligible to significant increases. Effects were species-specific and were largely limited to soils under A. mearnsii , which contained significantly more SOC in whole soil and in the macroaggregates (2000–250 μm) than non-planted soils. Mean rates of SOC accumulation in whole soils were 0.8 to 1.6 Mg C ha − 1 year − 1 greater under the N-fixing A. mearnsii than the non-N-fixing E. melliodora . At two of the sites, greater contribution of A. mearnsii than other tree species to new SOC was indicated by δ 13 C soil and litter data. δ 13 C data also pointed to greater responsiveness to tree establishment of SOC pools in mega- (8000–2000 μm) and macroaggregates than finer-sized fractions (microaggregate 250–53 μm; silt and clay Continued absence of disturbance from these and similar biodiverse plantings should ensure slow macroaggregate turnover and more secure contributions to soil C sequestration as the trees age. Given that greatest SOC effects in this study were under a species of relatively short life span ( A. mearnsii , ~ 10–20 years), soil C sequestration outcomes from biodiverse plantings might also be enhanced by the inclusion of a suite of N-fixing trees that encompass a range of life expectancies to ensure sustained SOC accumulation over many years.

Public expectations of soil management are gradually expanding beyond traditional primary production requirements to include diverse ecosystem services. In Australia, as in many other countries, the accommodation of these new expectations will require shifts in the practice of private land managers. In turn, this may require public intervention and the expenditure of public funds. However, public net benefits from soil management interventions are rarely established, in part due to a lack of understanding of the conceptual links between management changes, soil health, and associated services and benefits. This paper uses an ecosystem services-based approach to examine these links from an Australian perspective. Entrenchment of the popular soil health concept in field-based assessments of agricultural production potential was found to limit the concept's applicability to questions of broader public benefit. Without expanding soil health to include more ecological indicators, the concept risks remaining peripheral to contemporary visions of multiple-outcome soil management in Australia. Conceptual and case study links were examined between soil properties and processes, soil-based services, and private and public net benefits. In this framework, benefits were produced from services, and were considered a more tangible point for public understanding and valuation than services. The qualitative case study highlighted many knowledge gaps relating to non-agricultural services and benefits from soils, particularly in the scaling-up of sub-paddock measurements, and in the form and constancy of relationships among services and benefits. Criteria for identifying priority public benefits from soil management were examined, namely, likelihood, degree, consequence, scale, direction, time lag, and valuation. Assumptions about these criteria require rigorous testing so that the what, where, when, and how of public benefits from changed soil management can be more clearly defined.

While edge microclimates are well described for closed forests, they remain under-examined in more sparse vegetation types like the temperate woodlands of south-eastern Australia. This limits predictions of edge effects on remnant vegetation in cleared agricultural landscapes, and of changes in these effects with reforestation. Using fixed and roving weather stations, we examined influences on temperate woodland microclimate of adjoining land use (agriculture versus tree plantation), distance from edge (0–150 m), and woodland structural attributes (canopy openness, stem density and basal area). Shading by plantations significantly decreased temperatures and vapour pressure deficit (VPD) at woodland edges in winter (up to 0.8 °C and 75 Pa relative to agricultural edges). However, this effect was reversed in the non-winter months, when daytime temperatures and VPD were generally greater at plantation than agricultural edges (up to 0.5 °C and 300 Pa). This was the opposite of edge-type effects recorded for closed-forest types, and was explained by lower wind speeds at plantation edges, which led to the accumulation of heat in the 25 m firebreak between the two land uses. A similar ‘dead zone’ also apparently contributed to cooler, moister night-time conditions at plantation edges. Consistent with closed forests, and irrespective of edge type and season, we measured a depth of edge influence of 40–50 m for daytime temperature and VPD. However, magnitude of edge influence (ca. 0.5 °C and 100 Pa) was much less than in closed forests, and woodland interiors were warmer and drier than edges, whereas closed-forest interiors are usually cooler and moister than edges. This unique microclimate gradient into woodlands was explained both by decreasing wind speeds, and by positive relationships of temperature and VPD with basal area and stem density, highlighting the role of sub-canopy heat sinks like tree trunks in regulating interior microclimates of sparse vegetation types.

This study aimed to determine the response of native plant species to changed growing conditions, especially increased shade, following establishment of exotic Pinus radiata plantation on cleared native eucalypt forest. In the Northern Hemisphere, species tolerant to shading are typically herbaceous perennials, with large seeds, no obvious mechanism of seed dispersal, and spread by clonal means. We investigated whether life form, mode of seed dispersal, leaf area, specific leaf area (SLA), nutrient uptake strategy, seed mass, fire response, plant height, and clonal spread differed between understorey species of pine plantation and native forest. Further, we asked whether plant functional traits that confer tolerance to stress through shading differ from those in other floras. The study was conducted on the Delatite Peninsula in north-eastern Victoria, Australia. Vegetation of adjacent native forest and pine plantation were surveyed using eight 7 m × 7 m plots per site, randomly located within five paired sites. Differences in plant traits between land-use types were tested by Non-metric Multi-dimensional Scaling (NMDS), analysis of similarity (ANOSIM) and paired t-tests. Cluster analysis of the nine plant traits was used to define emergent groups, with differences between land-use types examined by ANOSIM and indicator species analysis. There was a significant change in the composition of understorey vegetation following conversion to pine plantation that included a decline in the richness of native species. NMDS of plant attributes showed a clear separation of native forest from pine plantation with land use strongly correlated in ordination space (r2 = 0.611). Cluster analysis produced seven emergent groups of plant functional traits for 78 identified plant species. Phanerophytes split into two groups (myrmecochorous trees and shrubs; myrmecochorous shrubs), perennial herbs into four groups (upright herbs, myrmecochorous herbs, barochorous herbs, flat rosette herbs) with one group representing therophytes and anemochorous perennials. Perennial herbs with intermediate SLA and clonal spread were tolerant of the shaded conditions in pine plantation while the two groups of phanerophytes and the myrmecochorous herbs were largely excluded. Shared traits of excluded emergent groups included those that provided an over-riding adaptation to mineral nutrient stress, including myrmecochory, low SLA, ectomycorrhizal and ericoid mycorrhizal associations and N2-fixation. These plant traits could not provide tolerance to stress through shading, which is better explained by the open canopied nature of the native forest.

Resource islands around woody plants are thought to define the structure and function of many semiarid and arid ecosystems, but their role in patterning of soil microbial communities remains largely unexamined in dry environments. This study examined soil resource distribution and associated fungal communities in two Allocasuarina luehmannii (buloke) remnants of semiarid north-western Victoria, Australia. These savannah-like woodlands are listed as endangered due to extensive clearing for agriculture. We used the DNA-based profiling technique T-RFLP and ordination-based statistical methods to compare fungal community compositions in surface soils from two remnants (located 1.6 km apart) and three sampling positions (beneath individual buloke canopies; grassy inter-canopy areas; and adjoining cleared paddocks). Resource island formation beneath buloke trees was clearly evident in soil physicochemical properties (e.g. threefold concentrations of total carbon and nitrogen in canopy versus non-canopy soils). This heterogeneity of resources was moderately correlated with soil fungal community compositions, which were distinct for each sampling position. We argue that fungal composition patterns reflected multiple roles of fungi in dryland ecosystems, namely: responses of saprotrophic fungi to tree organic matter inputs; specificity of ectomycorrhizal fungi to tree rooting zones; and fungal involvement in biological soil crusts that variably covered non-canopy soils. Our data did not indicate that buloke canopy areas were particular hotspots of soil fungal diversity, but that they increased landscape-level diversity by supporting a distinct suite of fungi. In addition, we provide evidence of phylogenetic differentiation of soil fungal communities between our two remnants, which adds to growing evidence of fungal genetic structure at localised scales. These findings highlight the importance of remnant trees in conserving both soil resources and microbial genetic diversity. In addition, evidence of differentiation of soil fungal phylogenetics between nearby but isolated remnants suggests that conserving soil fungal diversity requires conservation of host habitats over their entire (remaining) range, and indicates previously unseen consequences of tree loss from extensively cleared landscapes.

Complex soil microbial data produced by molecular profiling techniques, such as terminal restriction fragment length polymorphism (T-RFLP), are often analysed using multivariate statistical methods. Despite this, there has been little evaluation of the sensitivity of multivariate methods to routine data manipulations such as the application of noise thresholds. We examine effects of three percentage area thresholds (0.1%, 0.5% and 1.0%; i.e. ranging from low to commonly applied) on non-metric multidimensional scaling (NMDS) ordinations of soil fungal T-RFLP profiles. We then interpret threshold effects by introducing the concept of structural redundancy in T-RFLP data. NMDS ordinations compared 20 soil samples (encompassing seven sites, two forest types, and three locations) for T-RFLP presence/absence data, which were produced using primers specific to the rDNA internal transcribed spacer (ITS) region, and three separate restriction enzymes (HinfI, AluI and TaqI). Increasing thresholds from 0.1% to 1.0% led to decreases in average number of detected reproducible fragments per site of 57% (HinfI), 75% (AluI), and 69% (TaqI). However, despite the removal of many fragments unique to site/forest type/location, the application of increasing thresholds did not significantly change NMDS patterns for any enzyme in both the complete data and in a more weakly structured sub-group (involving one forest type and two locations). Thus, our data indicate that application of area thresholds up to 1.0% would have minimal impact on NMDS-based comparisons of soil fungal composition. Robustness of NMDS patterns to considerable fragment loss with increasing threshold suggested a degree of ‘structural redundancy’ in our T-RFLP data – that is, multiple fragments per soil sample were interchangeable in the way they contributed to between-sample NMDS patterns. Indeed, for each restriction enzyme, we found 3–4 peels of data (i.e. mutually exclusive sub-sets) that were capable of reproducing overall patterns in presence/absence data at the 0.1% threshold. Despite potential in the T-RFLP method for production of more than one fragment per fungal species/phylotype, we present arguments to support at least some translation of structural redundancy in T-RFLP data to structural redundancy in fungal community comparisons (i.e. the between-soil similarity patterns can be explained by, or are imprinted in, multiple groups of fungal phylotypes). Our analyses highlight structural redundancy as an efficient method for identifying key phylotypes responsible for differences in community composition among soils, and as a promising starting point for improved understanding of many aspects of spatial soil ecology.

Current theory expects that fungi, on the one hand, are spatially ubiquitous but, on the other, are more susceptible than bacteria to disturbance such as land use change due to dispersal limitations. This study examined the relative importance of location and land use effects in determining soil fungal community composition in south-eastern Australia. We use terminal restriction fragment length polymorphism (T-RFLP; primer pair ITS1-F-ITS4) and multivariate statistical methods (NMDS ordinations, ANOSIM tests) to compare relative similarities of soil fungal communities from nine sites encompassing three locations (ca 50-200 km apart) and four land uses (native eucalypt forest, Pinus radiata plantation, Eucalyptus globulus plantation, and unimproved pasture). Location effects were generally weak (e.g. ANOSIM test statistic R

Question: In the Northern Hemisphere, species with dispersal limitations are typically absent from secondary forests. In Australia, little is known about dispersal mechanisms and other traits that drive species composition within post-agricultural, secondary forest. We asked whether mode of seed dispersal, nutrient uptake strategy, fire response, and life form in extant vegetation differ according to land-use history. We also asked whether functional traits of Australian species that confer tolerance to grazing and re-colonisation potential differ from those in the Northern Hemisphere. Location: Delatite Peninsula, NE Victoria, Australia. Methods: The vegetation of primary and secondary forests was surveyed using a paired-plot design. Eight traits were measured for all species recorded. ANOSIM tests and Non-metric Multi-dimensional Scaling were used to test differences in the abundance of plant attributes between land-use types. Results: Land-use history had a significant effect on vegetation composition. Specific leaf area (SLA) proved to be the best predictor of response to land-use change. Primary forest species were typically myrmecochorous phanerophytes with low SLA. In the secondary forest, species were typically therophytes with epizoochorous dispersal and high SLA. Conclusions: The attributes of species in secondary forests provide tolerance to grazing suggesting that disturbance caused by past grazing activity determined the composition of these forests. Myrmecochores were rare in secondary forests, suggesting that species had failed to re-colonise due to dispersal limitations. Functional traits that resulted in species loss through disturbance and prevented re-colonisation were different to those in the Northern Hemisphere and were attributable to the sclerophyllous nature of the primary forest.