Dense White Cypress Pine (Callitris glaucophylla J. Thompson and L.A.S. Johnson) regrowth occurs frequently across previously cleared landscapes in New South Wales (NSW), and is thought to adversely affect agricultural production and to cause land degradation. The NSW Native Vegetation Act (2003) requires that management of native vegetation including pre-1990 regrowth must ‘improve or maintain’ site condition, yet there is currently limited information regarding techniques for the optimum management of C. glaucophylla in this regard. We conducted a preliminary study to examine floristic composition, soil condition (to 50 cm) and carbon storage under ‘Dense’ (dense regrowth), ‘Thinned’ (dense regrowth thinned 2000/2001) and ‘Un-colonised’ (pasture not yet recolonised by C. glaucophylla) plots on private lands in NSW. Reduced tree density from thinning resulted in increased biomass of the remaining individual trees. Un-colonised plots had significantly more groundcover than thinned plots, which had significantly more groundcover than dense plots. Differences in plant diversity however, were explained by site factors rather than land use. Soils in the dense plots were the most acid but soil pH was significantly higher in thinned plots and pH was highest in soil of the un-colonised plots. Mean values for carbon, nitrogen, sulphur and extractable phosphorus varied among sites, although each were significantly more abundant in the mineral soil of dense and thinned plots compared with un-colonised plots, suggesting that thinning had had a minimal effect on the soil parameters assessed. Accounting for all site components, site carbon storage was significantly higher in dense and thinned plots compared with un-colonised plots due to elevated levels of soil and litter carbon as well as the presence of trees. The results indicate that thinning dense C. glaucophylla can maintain and (by some measures) improve site condition. However, given the variability in some of the parameters assessed, further study across a wider range of soil types and rainfall gradients is proposed.

Item Type:	Refereed Article
Keywords:	Callitris glaucophylla, arbon storage, thinning, soil condition
Research Division:	Environmental Sciences
Research Group:	Environmental Science and Management
Research Field:	Environmental Management
Objective Division:	Environment
Objective Group:	Ecosystem Assessment and Management
Objective Field:	Ecosystem Assessment and Management of Farmland, Arable Cropland and Permanent Cropland Environments
Author:	McHenry, MT (Dr Melinda McHenry)
ID Code:	112389
Year Published:	2006
Web of Science® Times Cited:	17
Deposited By:	Geography and Spatial Science
Deposited On:	2016-11-08
Last Modified:	2016-12-15
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