${session.getAttribute("locale")} 5 Reforestation of agricultural land in the tropics: The relative contribution of soil, living biomass and debris pools to carbon sequestration Thu 20 Jun 2019 13:26:30 AEST ]]> Conversion of sub-tropical native vegetation to introduced conifer forest: Impacts on below-ground and above-ground carbon pools 0.05) in SOC or above-ground tree C stocks between paired native vegetation and pine plantations, although significant differences did exist at specific sites. SOC (calculated based on an equivalent soil mass basis) was higher in the pine plantations at two sites, higher in the native vegetation at two sites and did not differ for the other four sites. The site to site variation in SOC across the landscape was far greater than the variation observed with a change from native vegetation to introduced Pinus plantation. Differences between sites were not explained by soil type, although tree basal area was positively correlated with 0–50 cm SOC. In fact, in the native vegetation there was a significant linear relationship between above-ground biomass and SOC that explained 88.8% of the variation in the data. Fine litter C (0–25 mm diameter) tended to be higher in the pine forest than in the adjacent native vegetation and was significantly higher in the pine forest at five of the eight paired sites. Total litter C (0–100 mm diameter) increased significantly with plantation age (R2 = 0.64). Carbon stored in understorey woody plants (2.5–10 cm DBH) was higher in the native vegetation than in the adjacent pine forest. Total site C varied greatly across the study area from 58.8 Mg ha−1 at a native heathland site to 497.8 Mg ha−1 at a native eucalypt forest site. Our findings suggest that the effects of change from native vegetation to introduced Pinus sp. forest are highly site-specific and may be positive, negative, or have no influence on various C pools, depending on local site characteristics (e.g. plantation age and type of native vegetation).]]> Thu 20 Jun 2019 13:26:25 AEST ]]> Differential magnitude of rhizosphere effects on soil aggregation at three stages of subtropical secondary forest successions Mon 25 Mar 2019 11:40:45 AEST ]]> 10Be-derived denudation rates from the Burdekin catchment: The largest contributor of sediment to the Great Barrier Reef 100,000km2). In Australia, however, the approach and its assumptions have not been systematically tested within a single, large drainage basin. This study measures 10Be concentrations in river sediments from the Burdekin catchment, one of Australia's largest coastal catchments, to determine long-term (>10,000years), time-integrated rates of sediment generation and denudation. A nested-sampling design was used to test for effects of increasing catchment scale on nuclide concentrations with upstream catchment areas ranging from 4 to 130,000km2. Beryllium-10 concentrations in sediment samples collected from the upstream headwater tributaries and mid-stream locations range from 1.8 to 2.89×105atomsg-1 and data confirm that nuclide concentrations are well and rapidly mixed downstream. Sediment from the same tributaries consistently yielded 10Be concentrations in the range of their upstream samples. Overall, no decrease in 10Be concentrations can be observed at the range of catchment scales measured here. The mean denudation rate for all river sediment samples throughout the Fanning subcatchment (1100km2) is 18.47mMa-1, which compares with the estimate at the end of the Burdekin catchment (130,000km2) of 16.22mMa-1. Nuclide concentrations in the lower gradient western and southern catchments show a higher degree of variability, and several complications emerged as a result of the contrasting geomorphic processes and settings. This study confirms the ability of TCNs to determine long-term denudation rates in Australia and highlights some important considerations in the model assumptions that may affect the accuracy of limited sampling in large, low-gradient catchments with long storage times. © 2015 Published by Elsevier B.V.]]> Fri 08 Feb 2019 10:24:00 AEST ]]> Linkages among land use, macronutrient levels, and soil erosion in northern Vietnam: A plot-scale study Fri 08 Feb 2019 10:23:57 AEST ]]>