DOI: 10.5061/dryad.72h45
title: Data from: Hydrological conditions explain wood density in riparian plants of south-eastern Australia

description: 1. Wood density is a key plant functional trait which integrates the
 trade-offs characteristic to riparian plant ecological strategies.
 Although high-density wood is costly to construct, it confers mechanical
 stiffness to stems, increasing a plant's capacity to withstand
 flooding, and also enables increased tolerance to water stress. For
 riparian plants, fluctuations in soil moisture driven by surface hydrology
 should therefore be an important driver of variation in wood density. 2.
 We asked the following questions in the study: (1) Does wood density
 increase with increasing frequency and magnitude of flood disturbance? (2)
 Does wood density increase with increasing unpredictability of water
 availability in the riparian zone? (3) Does dispersion of wood density
 peak at intermediate levels of hydrological disturbance? 3. We surveyed
 wood density of dominant species at 15 riparian sites along flow-gauged
 rivers across south-eastern Australia. Due to the broad range of
 hydrological variability associated with Australian river systems, this
 set of sites functions as a useful model for assessing the response of
 riparian plants to changing hydrological conditions. 4. We found wood
 density varied strongly along a single axis of hydrological variability.
 This axis integrates flood intensity and frequency with metrics of
 hydrological unpredictability and can be conceptualized as a gradient of
 environmental harshness, with higher wood density associated with harsher
 conditions. 5. Synthesis. Our study highlights the importance of
 hydrological conditions, particularly disturbance and environmental
 unpredictability, as determinants of ecological strategy in riparian
 plants. Large, rare flood events in particular appear to favour higher
 wood density strategies. This is likely to have significant ecological
 consequences for riparian plant communities in a south-east Australian
 context, as well as in other regions where increasing climatic variability
 and frequency of extreme events are hallmarks of climate change
 predictions.
description: Riparian wood density
 dataThis file contains: the
 names, proportional abundances and wood density values (in g/cm^3) of
 species found at fifteen riparian plots across south eastern Australia.
 Wood density values given in the column "fieldWD" were measured
 in the field from individuals within the appropriate plot. Species which
 were present in plots but which could not be cored due to small size were
 assigned averaged values of wood density from the same species measured at
 other sites, where possible; the column "allFieldWD" includes
 these values. Remaining species were assigned values from peer-reviewed
 literature sources; the column "allWD" includes all values used
 in the analysis.riparian wood density
 data.csvHydrological
 metricsThis file contains the
 set of 24 statistical metrics of hydrology for each site, as described in
 the manuscript. Please refer to the manuscript for definitions of each
 metric. As of April 2015 Full daily discharge data for these sites is
 available from the NSW Office of Water Continuous Water Monitoring network
 website (http://realtimedata.water.nsw.gov.au/water.stm) for NSW sites,
 and the Victoria State Government’s Water Measurement Information System
 website (http://data.water.vic.gov.au/monitoring.htm) for Victorian
 sites.hydrology.csv