
%0 Journal Article
%A Schwenke, G. D. 
%A Mulligan, D. R. 
%A Bell, L. C. 
%T Soil stripping and replacement for the rehabilitation of bauxite-mined land at Weipa. III. Simulated long-term soil organic matter development
%J Soil Research
%D 2000/02/29
%V 38
%N 2
%P 395-410
%K CENTURY model, organic matter pools, organic matter accumulation, organic matter equilibrium, organic carbon, soil nitrogen.
%R https://doi.org/10.1071/SR99045
%U https://www.publish.csiro.au/paper/SR99045 
%X Long-term trends in soil organic carbon (C) and nitrogen (N) under current and alternative rehabilitation practices at Weipa were simulated using the CENTURY model. After 100 years, predicted organic C in the surface soils (0&#8211;20 cm) of each treatment had risen to new dynamic equiliPbria. Since the &#8216;passive&#8217; pool of recalcitrant organic C, which occupied 47% of organic C, changed little over the simulation period, the new equilibria differed according to initial organic C content. Most organic matter recovery occurred in the &#8216;slow&#8217; fraction, although the greatest rate of change occurred in the &#8216;active&#8217; C pool, which stabilised within 50 years at levels similar to the native forest. Similarly, &#8216;slow&#8217; C accumulated in all treatments to new equilibria which were similar to that in undisturbed forest soil. The main difference between treatments was in the predicted time until a stable equilibrium in the &#8216;slow&#8217; pool was reached: between 90 and 160 years depending on the soil stripping and replacement operation used. Successful development of new equilibria was highly sensitive to the amount of legume N2 fixation in the system and also to the severity of C and N losses during fire events. Reasonable agreement was found between simulated organic C accumulation and that observed in surveyed rehabilitation of up to 15 years of age (r2 = 0.67 for freshly replaced soils, r2 = 0.72 for soils stockpiled before respreading). 
