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Sediment transport and soil erosion can be determined by a variety of field and modelling approaches. Computer based soil erosion and landscape evolution models (LEMs) offer the potential to be reliable assessment and prediction tools. An advantage of such models is that they provide both erosion and deposition patterns as well as total catchment sediment output. However, before use, like all models they require calibration and validation. In recent years LEMs have been used for a variety of both natural and disturbed landscape assessment. However, these models have not been evaluated for their reliability in steep forested catchments. Here, the SIBERIA LEM is calibrated and evaluated for its reliability for two steep forested catchments in south-eastern Australia. The model is independently calibrated using two methods. Firstly, hydrology and sediment transport parameters are inferred from catchment geomorphology and soil properties and secondly from catchment sediment transport and discharge data. The results demonstrate that both calibration methods provide similar parameters and reliable modelled sediment transport output. A sensitivity study of the input parameters demonstrates the model’s sensitivity to correct parameterisation and also how the model could be used to assess potential timber harvesting as well as the removal of vegetation by fire. [ABSTRACT FROM AUTHOR]

There have been very few clinical trials evaluating therapies for naturally occurring spinal cord injury in dogs and cats. This review describes the methods suitable for evaluating the behavioural recovery of animals with spinal cord injuries, in either a clinical or a laboratory setting. A list of commonly used methods for evaluating behavioural recovery in animals is provided, both in the clinical and laboratory setting; the tests, their limitations and benefits and specific recommendations for their use are also discussed in more depth. [ABSTRACT FROM AUTHOR]

Stream sediment loads (both bedload and suspended sediment) are problematic to measure due to the time and equipment needed. There is a dearth of such data sets globally let alone for Australia. However, such data are needed to quantify sediment transport type and rates, landscape evolution, effect of human disturbance as well as patterns and temporal response. Here we present the findings from 8 steepslope forested catchments dominated by headwater streams (size range 15–100 ha) in south-eastern Australia where both bedload and suspended load have been measured over multiple years. The results demonstrate that suspended load is the dominant component and there is no consistent suspended to bedload ratio for the catchments. The suspended sediment to bedload ratio appears to be catchment specific. There was no relationship between total load (or bedload/suspended load) and average catchment slope, stream length, shape or any geomorphic descriptor. However catchment total load was found to be significantly related to catchment area. Of the 8 catchments examined here, 6 had been harvested for timber in previous decades (with large areas of forest removed) while 2 catchments had minimal disturbance (Control catchments). There was no difference in sediment loads from the harvested and Control catchments. The results demonstrate that although land disturbance had previously occurred the management practices employed in each catchment were effective in the long term. This provides confidence that the forest harvesting and subsequent management do not produce detrimental effects in the medium to long term. An assessment of erosion rates and likely soil production rates suggests that the catchments are eroding soil at the rate it is being produced. [ABSTRACT FROM AUTHOR]

• We examine eight steep slope forested headwater catchments (15–100 ha). • Bedload organic carbon (OC), soil carbon and dissolved OC was measured. • OC in the bedload was found to be significantly related to catchment area. • Dissolved OC export in stream water declined with catchment area. • There was no difference in OC export from the harvested and non-harvest catchments. Qualitative and quantitative understandings of the origin, transport and fate of organic carbon (OC) in forest systems is needed to advance our understanding of biogeochemical cycling as well as catchment management and forest harvesting. Here we present the findings from eight steep slope forested catchments dominated by headwater streams (size range 15–100 ha) in south eastern Australia where bedload, organic carbon in bedload, hillslope soil carbon together with dissolved organic carbon has been measured over multiple years. OC in the bedload was found to be significantly related to catchment area (p < 0.02). Dissolved organic carbon export in stream water declined with catchment area. Combined bedload organic carbon and dissolved organic carbon export was significantly related to catchment area. There was no significant difference between hillslope soil organic carbon and bedload organic carbon concentration. When corrected for area, OC export by bedload was not significantly different to that of dissolved OC export. Using the environmental tracer 137Cs it was found that there was no significant difference in tracer concentration between bedload and hillslope soil. This suggests a direct link between hillslope and channel and delivery of organic carbon to the channel. Of the eight catchments examined here, six had been harvested for timber in previous decades (with area of forest removed ranging from 25 to 60%) while two catchments had minimal disturbance (Control catchments- no harvest). There was no difference in organic carbon export from the harvested and Control catchments. The results demonstrate that although land disturbance had previously occurred the management practices employed in each catchment were effective in the long term. [ABSTRACT FROM AUTHOR]

• We examine eight steep slope forested headwater catchments (15–100 ha). • Bedload organic carbon (OC), soil carbon and dissolved OC was measured. • OC in the bedload was found to be significantly related to catchment area. • Dissolved OC export in stream water declined with catchment area. • There was no difference in OC export from the harvested and non-harvest catchments. Qualitative and quantitative understandings of the origin, transport and fate of organic carbon (OC) in forest systems is needed to advance our understanding of biogeochemical cycling as well as catchment management and forest harvesting. Here we present the findings from eight steep slope forested catchments dominated by headwater streams (size range 15–100 ha) in south eastern Australia where bedload, organic carbon in bedload, hillslope soil carbon together with dissolved organic carbon has been measured over multiple years. OC in the bedload was found to be significantly related to catchment area (p < 0.02). Dissolved organic carbon export in stream water declined with catchment area. Combined bedload organic carbon and dissolved organic carbon export was significantly related to catchment area. There was no significant difference between hillslope soil organic carbon and bedload organic carbon concentration. When corrected for area, OC export by bedload was not significantly different to that of dissolved OC export. Using the environmental tracer 137Cs it was found that there was no significant difference in tracer concentration between bedload and hillslope soil. This suggests a direct link between hillslope and channel and delivery of organic carbon to the channel. Of the eight catchments examined here, six had been harvested for timber in previous decades (with area of forest removed ranging from 25 to 60%) while two catchments had minimal disturbance (Control catchments- no harvest). There was no difference in organic carbon export from the harvested and Control catchments. The results demonstrate that although land disturbance had previously occurred the management practices employed in each catchment were effective in the long term. [ABSTRACT FROM AUTHOR]