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This study offers an analytical solution for radial consolidation that captures the biogeochemical clogging effect in acid sulfate soils. Field sites and personal communication with industry practitioners have provided evidence of piezometers exhibiting retarded pore pressure readings that do not follow conventional soil consolidation and seepage principles when installed in coastal acidic floodplains. This retarded response together with a variation in pH, ion concentrations, and piezometric heads provided evidence of clogging at and around the piezometers. This paper uses the proposed biogeochemical clogging model, which is an analytically derived system of equations to estimate the excess pore water pressure dissipation of piezometers installed in clogging-prone acid sulfate soils. The inclusion of the total porosity reduction attributed to biological and geochemical clogging improves the predictions of the retarded dissipation of excess pore pressure, especially after about 1 year. This method is validated for two previously identified acidic field sites in coastal Australia, where piezometers measured a very slow rate of dissipation. It is concluded that this model has potential to accurately monitor the performance of critical infrastructure, such as dams and embankment foundations built on acidic terrain. [ABSTRACT FROM AUTHOR]

Novel ecosystems occur when new combinations of species appear within a particular biome. They typically result from direct human activity, environmental change, or the impacts of introduced species. In this paper, we argue that considering commercial tree plantations as novel ecosystems has the potential to help policy makers, resource managers, and conservation biologists better deal with the challenges and opportunities associated with managing plantations for multiple purposes at both the stand and landscape scales. We outline five inter-related issues associated with managing tree plantations, which are arguably the largest form of terrestrial novel ecosystem worldwide. This is to ensure that these areas contribute significantly to critical ecosystem services, including biodiversity conservation, in addition to their wood production role. We suggest that viewing tree plantations as novel socioecological systems may free managers from a narrow stand-based perspective and having to compare them with natural forest stands. This can help promote the development of management principles that better integrate plantations into the larger landscape so that their benefits are maximized and their potential negative ecological effects are minimized. [ABSTRACT FROM AUTHOR]