Carbon and nitrogen dynamics in native and plantation forests over periods from 1 to 17 years after site managements in subtropical Australia

Forest ecosystems fulfil crucial roles in mediating greenhouse gases and in harbouring biodiversity and providing products to humankind, meanwhile they are subjected to challenges from human activities and climate change. To test how prescribed burning and harvest compaction would influence the carbon (C) and nitrogen (N) cycles in forest ecosystems in the long term, we conducted a series of experiments in a natural forest and a hoop pine (Araucaria cunninghamii) plantation in subtropical Australia. Those experiments included collecting litter and soil samples from Toohey Forest to examine role of regular patch mosaic prescribed burning in regulating soil C and N pools. In situ incubations in Toohey Forest were used to assess the soil N transformations with time after prescribed burning. 15N natural abundance ([delta-N-15]) of inorganic N pools was used to quantify the responses of soil N transformation processes to elevated soil moisture which was used to mimic heavy rainfall. Collecting soil and foliage samples, measuring tree diameter at breast height over bark (DBHoB) and height in a 17-year-old machinery compaction trail site in a hoop pine plantation, Yarraman State Forest, was used to investigate the long-term impacts of harvesting compaction on soil C and N pools, and on forest productivity. [...]
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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