Vegetation and floristics of a lowland tropical rainforest in northeast Australia

Background: Full floristic data, tree demography, and biomass estimates incorporating non-tree life forms are seldom collected and reported for forest plots in the tropics. Established research stations serve as important repositories of such biodiversity and ecological data. With a canopy crane setup within a tropical lowland rainforest estate, the 42-ha Daintree Rainforest Observatory (DRO) in Cape Tribulation, northern Australia is a research facility of international significance. We obtained an estimate of the vascular plant species richness for the site, by surveying all vascular plant species from various mature-phase, remnant and open vegetation patches within the site. We also integrate and report the demography and basal areas of trees ≥ 10 cm diameter at breast height (dbh) in a new 1- ha core plot, an extension to the pre-existing forest 1-ha plot under the canopy crane. In addition, we report for the canopy crane plot new demography and basal areas for smaller size shrubs and treelets subsampled from nine 20 m quadrats, and liana basal area and abundance from the whole plot. The DRO site has an estimated total vascular plant species richness of 441 species, of which 172 species (39%) are endemic to Australia, and 4 species are endemics to the Daintree region. The 2 x 1-ha plots contains a total of 262 vascular plant species of which 116 (1531 individuals) are tree species ≥ 10 cm dbh. We estimate a stem basal area of 34.9 m ha, of which small stems (tree saplings and shrubs <10cm dbh) and lianas collectively contribute c.4.2%. Comparing the stem density-diversity patterns of the DRO forest with other tropical rainforests globally, our meta-analysis shows that DRO forests has a comparatively high stem density and moderate species diversity, due to the influence of cyclones. These data will provide an important foundation for ecological and conservation studies in lowland tropical forest. New information: We present a floristic checklist, a life form breakdown, and demography data from two 1-ha rainforest plots from a lowland tropical rainforest study site. We also present a meta-analysis of stem densities and species diversity from comparable-sized plots across the tropics

Climate Predictions Accelerate Decline for Threatened Macrozamia Cycads from Queensland, Australia

Changes in the potential habitat of five allopatric species of threatened Macrozamia cycads under scenarios of increased ambient temperature were examined. A lack of seed dispersal, poor recruitment, low seedling survival, obligate pollinator mutualisms and continued habitat loss have led to extant populations being largely restricted to refugia. Models predict that the area of suitable habitat will further contract and move upslope, resulting in a reduced incidence within protected areas with increasing annual mean temperature. Areas of potential habitat for all five species are also predicted to become increasingly isolated from one another, further reducing the exchange between metapopulations and subpopulations, exacerbating existing threatening processes

Subtropical rainforest turnover along an altitudinal gradient

Volume: 55Start Page: 271End Page: 29

Identifying indicator species of elevation: Comparing the utility of woody plants, ants and moths for long-term monitoring

© 2016 Ecological Society of Australia. Ecologists have found the distributions of many groups of organisms to be elevationally stratified. Consequently, various taxa (or species) have been proposed as indicators for inclusion within long-term monitoring programmes to quantify the ecological impacts of future climatic change. Ideal indicators should be restricted to a particular elevational range (i.e. have high specificity) and be readily detectable across space and time (i.e. have high fidelity). This, however, has not been rigorously tested for elevational studies. We employed a spatially and temporally replicated sampling design to test the utility of tree, ant, and canopy and understorey moth species as indicators of elevation within continuous subtropical rainforest of eastern Australia. Using the classical indicator value protocol, we tested (i) whether the number of indicator species (all taxa) found in the observed data was significantly greater than the number obtained by chance; (ii) whether the indicator species (ants and moths) identified from one sampling season responded to elevation in a similar way in samples obtained from other seasons; and (iii) whether the indicator species (ants) identified from one elevational transect responded to elevation in a similar way in a nearby transect that incorporated similar elevational ranges. All groups had significantly greater numbers of indicator species than expected by chance. Temporal fidelity of moth indicator species was lower than that of ants as the suite of moth indicator species showed high seasonal variation. In contrast, ants showed high spatial and temporal fidelity. Most ant indicator species were, however, indicative of low and mid-elevations, and only one species was indicative of the highest elevation, suggesting their relatively low conservation significance in relation to climate warming in this region. It is essential that we understand how spatial and temporal variation affects the distributions of different taxonomic groups when incorporating multiple taxa for long-term monitoring programmes.Link_to_subscribed_fulltex

THE PHYSICAL ENVIRONMENT OF AN ALTITUDINAL GRADIENT IN THE RAINFOREST OF LAMINGTON NATIONAL PARK SOUTHEAST QUEENSLAND

Climate and soil properties are key factors influencing vegetation and biota. As such, an understanding of the variability in climate and soil properties along an altitudinal gradient can be used to explain changes in vegetation and biota along the same gradient. Understanding these patterns can offer a powerful predictive tool with respect to changes in climate. The temperature, relative humidity and wind speed and direction were logged throughout the day and night for up to 333 days continuously at five different altitudes in the subtropical rainforest of Lamington National Park, Queensland, Australia. In addition, soil sampling was carried out at the same sites and elements of the physical, chemical and mineralogical characteristics of the soil tested. Temperature decreased with increased altitude, although less temperature variability was experienced at higher altitudes. All sites experienced relative humidity close to 100% for most nights throughout the year, although daily temperature increases reduced humidity at most sites. Increasing windiness at the highest (1100 m above sea level (a.s.l.)) altitude reflected meso-scale synoptic conditions. Soils demonstrated increasing moisture, organic matter and acidity as elevation increased. The macro- and micro-nutrients measured showed variable responses with nitrogen increasing and the other macro-nutrients decreasing with altitude. Aluminium increased exponentially with altitude. Moisture and temperature appear to be important drivers in soil parameters and therefore biological patterning along the transect. Future climate change resulting in atmospheric warming and drying are predicted to have a significant impact on moisture availability both in the canopy and soil environments

Detecting Biodiversity Changes Along Climatic Gradients: The IBISCA-Queensland Project

The IBISCA-Queensland project established 20 permanent plots over an altitudinal range of 300 m to 1100 m above sea-level (a.s.l.) in rainforest within Lamington National Park, south-east Queensland. Four replicate plots were established at each 200 m interval, representing an average temperature change between altitudes of about 1.5°C - a full range of approximately 7.5°C. The project aimed to identify which animal and plant groups are likely to be most sensitive to climate change and which ones can best be used as indicators for monitoring such change. Full vegetation analyses were carried out at each plot and basic climatic and soil data collected. Over an 18 month period insect collections, using a wide-range of trapping methods, were made and specific projects carried out by more than 55 scientists from 14 countries. This paper summarises the history and goals of the project and the general 'IBISCA' model within which it was conceived. Site locations are presented, as is an outline of the specific trapping programme and more specific projects carried out within the broader objectives of IBISCA-Queensland. The strengths and weaknesses of the IBISCA approach are discussed. The first comparative syntheses are anticipated and a broader context for future work is defined. © The State of Queensland (Queensland Museum) 2011.Link_to_subscribed_fulltex

The physical environment of an altitudinal gradient in the rainforest of Lamington National Park, southeast Queensland

Volume: 55Start Page: 251End Page: 27

Detecting biodiversity changes along climatic gradients: the IBISCA-Queensland Project

Volume: 55Start Page: 235End Page: 25

Vertical stratification of moths across elevation and latitude

Aim: There is little consensus as to whether stratification of arthropods between canopy and understorey in tropical and subtropical forests is commonplace and if the magnitude of stratification changes across different elevations and latitudes. We investigated broad-scale patterns of vertical stratification of moths collected from extensive cross-continental fieldwork in a variety of forest types, climates, elevations, latitudes and areas with differing biogeographical history. Location: Tropical and subtropical rain forest in eastern Australia; tropical, subtropical and subalpine forest in Yunnan Province, China; and tropical rain forest in Panama, Vietnam, Brunei and Papua New Guinea. Methods: Night-flying moths were trapped from the upper canopy and understorey. We generated a total of 64 data sets to quantify vertical stratification of moths in terms of their species richness, using coverage-based rarefaction, and assemblage composition, using standardized hierarchical beta diversity. Based on the average temperature lapse rate, we incorporated latitudinal differences into elevation and generated 'corrected' elevation for each location, and analysed its relationships with the magnitude of stratification. Results: We found consistent differences between canopy and understorey assemblages at almost all rain forest locations across corrected elevational gradients. The magnitude of vertical stratification in species richness did not change with increasing corrected elevation. In contrast, the difference in assemblage composition increased with increasing corrected elevation in the Northern Hemisphere, while the opposite, albeit weak, trend was found in the Southern Hemisphere. Main conclusions: Clear vertical stratification was evident in moth assemblages regardless of elevation and latitude. However, the degree to which assemblages are stratified between canopy and understorey is not uniformly related to elevation and latitude. Inconsistencies in the magnitude of vertical stratification between the Northern and Southern Hemisphere, may reflect, on one hand, deep-time biogeographical differences between the land masses studied and, on the other, place-to-place differences in resource availability underpinning the observed moth assemblages