Tropical Rainforest Plot Network: Understorey Floristic Data, Northern Queensland, Australia, 1972-2016

Abstract: The Tropical Rainforest Plot Network Rainforest Understorey Floristic Data contains understorey floristic data from all 20 of its 0.5 ha (100 m x 50 m) permanent rainforest plots in Northern Queensland, Australia. Data was collected for all plots at the time of establishment before 1981 and data was again collected for half of the plots post-2000.

The CSIRO permanent rainforest plots are located within 60 km of the north Queensland coast between Mackay (21.5ºS, 149ºE) and the Iron Range on Cape York Peninsula (12.5ºS, 143ºE). The plots have a rainfall range of 1200 to 3500 mm, represent eleven vegetation types, six parent materials, and range from 15 m to 1200 m above sea level. Except for minor disturbances associated with selective logging on two plots, the plots were established in old growth forest and all plots have thereafter been protected. In conjunction with the Tree Demographic Data packages which have been collected by the Tropical Rainforest Plot Network, the data collected from these 20 plots provides an insight into the floristical composition, structure and long term forest dynamics of Australian tropical rainforests and allows direct comparisons to be made with long-term monitoring plots at a global scale.

For further background data please refer to Bradford, M.G., Murphy, H.T., Ford, A.J., Hogan, D. and Metcalfe, D.J. (2014) "Long-term stem inventory data from tropical rain forest plots in Australia", Ecology, 95(8): 2362. Ecological Archives E095-209-D1, https://doi.org/10.1890/14-0458R.1.

A synopsis of related data packages which have been collected as part of the Tropical Rainforest Plot Network’s full program is provided at hhttps://doi.org/10.25911/5c3c249fbe8ee..

Data between 1971 and 2013 can be also be sourced from CSIRO Data Access Portal at http://doi.org/10.4225/08/59475c67be7a4.

Sampling method: The 20 CSIRO permanent plots were opportunistically located ahead of logging operations or in areas of no or minor recent disturbance (EP9 and EP38 showed evidence of slight disturbance in a section of the plot due to selective logging at least 20 years prior to establishment). Where possible, plots were located to represent the major forests and geologies of North Queensland. All plots were surveyed to enclose a projected plan view area of 0.5 ha (100 m x 50 m) with plot boundary distances corrected for slope. The resulting plot areas are presented in Table 2.

Plot boundaries were surveyed with prismatic compasses, 50 m steel survey band and Abney level. The four plot corners were initially marked with treated wooden pegs and subsequently replaced with steel pickets. All plots were subdivided into 16 subplots (A to P), each 25 m x 12.5 m with permanent wooden subplot markers. A 20 m buffer area around each plot was established to exclude future human disturbance. A canopy tower was located adjacent to both EP4 and EP33 from establishment until 2005 and focussed on canopy sampling and photosynthetic studies. Data from the towers is not included in this data package, but have been included in associated publications.

The plots were established between 1971 and 1980 and were initially censused every two years until 1991, and at intervals of 2-15 years thereafter.

Species References:
- Bostock, P. D., and A. E. Holland (2010). Census of the Queensland flora 2010. Toowoong: Queensland Herbarium.
- Henderson, R.J.F. (ed) (2002). Names and distribution of Queensland plants, algae and lichens. Toowoong: Queensland Herbarium.

Study extent: The study was conducted in the rainforests of North Queensland, Australia between Mackay 21.5ºS, 149ºE and the Iron Range 12.5ºS, 143ºE.

The plots span much of the geographical variation in environmental gradients across the study area and represent eleven moist humid tropical vegetation (Tracey, J. G. 1982. The vegetation of the humid tropical region of North Queensland. CSIRO Publishing, Melbourne.), six parent material types, and range from 15 m to 1200 m asl. The climate is tropical with mean annual rainfall ranging from 1200 mm to over 8000 mm on the higher coastal ranges. Seventeen of the plots are located within the Wet Tropics Bioregion which is broadly composed of closed canopy rainforest and open Eucalyptus forests and woodlands.

Continuous areas of rainforest account for approximately 6300 km2 of the region (Tracey 1982 as above) and are found in the wetter and mountainous areas where the rainfall exceeds 1500 mm.

Project funding: Commonwealth Forest and Timber Bureau (1971-1978), CSIRO internal funding (1978-1992), Tropical Rainforest Ecology and Management and the Rainforest Cooperative Research Centres (1992-2006), Earthwatch (2006). S

Between 2012 and 2018 this project was part of, and funded through the Long Term Ecological Research Network (LTERN) a facility within the Terrestrial Ecosystem Research Network (TERN) and supported by the Australian Government through the National Collaborative Research Infrastructure Strategy.