title: Modelling water, sediment and nutrient fluxes from a mixed land-use catchment in New Zealand: effects of hydrologic conditions on SWAT model performance

authors: Me, W.

abstract: The Soil Water Assessment Tool (SWAT) was configured for the Puarenga Stream catchment (77 km2), Rotorua, New Zealand. The catchment land use is mostly plantation forest, some of which is spray-irrigated with treated wastewater. A Sequential Uncertainty Fitting (SUFI-2) procedure was used to auto-calibrate unknown parameter values in the SWAT model which was applied to the Puarenga catchment. Discharge, sediment, and nutrient variables were then partitioned into two components (base flow and quick flow) based on hydrograph separation. A manual procedure (one-at a-time sensitivity analysis) was then used to quantify parameter sensitivity for the two hydrologically-separated regimes. Comparison of simulated daily mean discharge, sediment and nutrient concentrations with high-frequency, event-based measurements allowed the error in model predictions to be quantified. This comparison highlighted the potential for model error associated with quick-flow fluxes in flashy lower-order streams to be underestimated compared with low-frequency (e.g. monthly) measurements derived predominantly from base flow measurements. To overcome this problem we advocate the use of high-frequency, event-based monitoring data during calibration and dynamic parameter values with some dependence on discharge regime. This study has important implications for quantifying uncertainty in hydrological models, particularly for studies where model simulations are used to simulate responses of stream discharge and composition to changes in irrigation and land management.

text: Modelling water, sediment and nutrient fluxes from a mixed land-use catchment in New Zealand: effects of hydrologic conditions on SWAT model performance The Soil Water Assessment Tool (SWAT) was configured for the Puarenga Stream catchment (77 km2), Rotorua, New Zealand. The catchment land use is mostly plantation forest, some of which is spray-irrigated with treated wastewater. A Sequential Uncertainty Fitting (SUFI-2) procedure was used to auto-calibrate unknown parameter values in the SWAT model which was applied to the Puarenga catchment. Discharge, sediment, and nutrient variables were then partitioned into two components (base flow and quick flow) based on hydrograph separation. A manual procedure (one-at a-time sensitivity analysis) was then used to quantify parameter sensitivity for the two hydrologically-separated regimes. Comparison of simulated daily mean discharge, sediment and nutrient concentrations with high-frequency, event-based measurements allowed the error in model predictions to be quantified. This comparison highlighted the potential for model error associated with quick-flow fluxes in flashy lower-order streams to be underestimated compared with low-frequency (e.g. monthly) measurements derived predominantly from base flow measurements. To overcome this problem we advocate the use of high-frequency, event-based monitoring data during calibration and dynamic parameter values with some dependence on discharge regime. This study has important implications for quantifying uncertainty in hydrological models, particularly for studies where model simulations are used to simulate responses of stream discharge and composition to changes in irrigation and land management.

year: 2015-04-29

title: Religious conversions in the Mediterranean world [Book Review]

authors: Drury, Abdullah

abstract: This article reviews the book 'Religious conversions in the Mediterranean world', edited by Nadia Marzouki and Oliver Roy.

text: Religious conversions in the Mediterranean world [Book Review] This article reviews the book 'Religious conversions in the Mediterranean world', edited by Nadia Marzouki and Oliver Roy.

year: 2014-06

title: Ōpōtiki Mai Tawhiti

authors: Maxwell, Te Kahautu

abstract: Ōpōtiki Mai Tawhiti competed at the Mātaatua Regional Kapa Haka Competition 2014 to qualify for the Te Matatini World Championship Kapa Haka Competition 2015, Christchurch. Ōpōtiki Mai Tawhiti placed first overall, 1st mōteatea, 1st, Haka, 1st Whakawātea, 1st Female Leader, 1st Male Leader, 1st Waiata Tira, 1st Te Reo, 1st Original Composition, 1st Costume, 2nd Waiata a Ringa, 2nd, Poi, 2nd Whakaeke.

text: Ōpōtiki Mai Tawhiti Ōpōtiki Mai Tawhiti competed at the Mātaatua Regional Kapa Haka Competition 2014 to qualify for the Te Matatini World Championship Kapa Haka Competition 2015, Christchurch. Ōpōtiki Mai Tawhiti placed first overall, 1st mōteatea, 1st, Haka, 1st Whakawātea, 1st Female Leader, 1st Male Leader, 1st Waiata Tira, 1st Te Reo, 1st Original Composition, 1st Costume, 2nd Waiata a Ringa, 2nd, Poi, 2nd Whakaeke.

year: 2014-02-22