From 1 - 5 / 5
  • Categories    

    The woody vegetation extent for Queensland is attributed with an estimated age in years since the last significant disturbance. The method uses a sequential Conditional Random Fields classifier applied to Landsat time series starting 1988 to predict woody cover over the time period. A set of heuristic rules is used to detect and track regrowing woody vegetation in the time series of woody probabilities and record the approximate start and end dates of the most recent regrowth event. Regrowth detection is combined with the Statewide Land and Trees Study (SLATS) Landsat historic clearing data to provide a preliminary estimate of age since disturbance for each woody pixel in the woody extent. The 'last disturbance' may be due to a clearing event or other disturbance such as fire, flood, drought-related death etc. Note that not all recorded disturbances may result in complete loss of woody vegetation, so the estimated age since disturbance does not always represent the age of the ecosystem. The age since disturbance product is derived from multiple satellite image sources and derived products which represent different scales and resolutions: Landsat (30 m), Sentinel-2 (10 m) and Earth-i (1 m).

  • Categories  

    Age-specific (per year) numbers of human females, males, mortality and fertility rates. Ages 1-100. Number and mortalities from WHO-CHOICE project (www.who.int/choice) and fertility derived from U.S. Census Bureau International Data Base (www.census.gov/population/international/data/idb).

  • Categories    

    This dataset comprises of new, high precision radiocarbon dates for 20 mainland thylacines and 24 mainland devils. Metadata includes museum accession numbers and origin of specimens. We envision that this dataset could be used in studies of paleo-ecological reconstructions and for estimating extinction time for both devils and thylacines on mainland Australia. This dataset includes the youngest reliable fossil ages for both species on mainland Australia as per the criteria set out in Rodriguez-Rey at al (2015). <i>"Criteria for assessing the quality of Middle Pleistocene to Holocene vertebrate fossil ages."</i> Quaternary Geochronology 30 (2015): 69-79.

  • Categories    

    FosSahul is the first database compiling the ages of nonhuman vertebrate fossils from the Middle Pleistocene to the present in the Sahul region. It includes comprehensive metadata with ratings of reliability allocated to each fossil age. Because ecological and evolutionary phenomena are time-dependent, the entire range of archaeological and palaeontological research disciplines benefit from the availability of this data.

  • Categories  

    Experimental sites were established in the northern wheat-growing district of western Australia (Lat -29.66°, Long 116.18°) in August 2017, and monitored through to November 2019. We selected five planted old field sites with similar soil types and vegetation composition. Old fields were planted with York gum (Eucalyptus loxophleba Benth.) and dominant shrubs as understorey. At the time of sampling in 2017, vegetation age ranged from 8–13 years and distance from remnant measured 279 m (± 162 m). We established two control and two treatment plots, each measuring 5 m x 5 m, in the interrows of five planted old field sites. Both treatments were randomly assigned to plots within each site. Between August and early November 2017, we measured a total of 30 response variables at each of the control and treatment plots. Response variables included soil physical and chemical properties (bulk density, penetration resistance, soil moisture, nitrogen and carbon pools), microbial biomass, decomposition rate of roiboos and green tea as per the standardized Tea Bag Index (TBI) protocol, herbaceous vegetation cover and richness, and ant abundance and richness, as well as abundance and richness of ant functional groups.