dc.contributor.author | Oezkundakci, D | |
dc.contributor.author | McBride, CG | |
dc.contributor.author | Hamilton, DP | |
dc.contributor.editor | Brebbia, CA | |
dc.date.accessioned | 2017-05-18T02:01:47Z | |
dc.date.available | 2017-05-18T02:01:47Z | |
dc.date.issued | 2012 | |
dc.identifier.issn | 1743-3541 | |
dc.identifier.doi | 10.2495/WP120151 | |
dc.identifier.uri | http://hdl.handle.net/10072/337295 | |
dc.description.abstract | Numerical models of aquatic ecosystems that couple physics and
biogeochemistry are valuable tools in aquatic ecosystem research. These models
provide opportunities to test theories and to inform environmental management.
In this study, we used the dynamic, process-based hydrodynamic-ecological
model DYRESM-CAEDYM to simulate key ecosystem processes of Lake
Rotorua, New Zealand, for six 8-year periods between 1920 and 2100 in order to
evaluate the potential effects of future changes in land use and climate. Longterm
variations in external boundary conditions (e.g. inflows) to the lake
ecosystem are incorporated by varying the relevant input files in the DYRESMCAEDYM
model. However, quantification of internal lake processes,
specifically those at the sediment-water interface, presents a major challenge for
long-term simulations. The sediment model within CAEDYM is ‘static’, with
assumed constant sediment composition and a relatively simplistic process
representation for nutrient and oxygen fluxes between sediment and water.
Specifically, the model regulates sediment phosphate and ammonium release
according to concentrations of oxidising species (i.e. oxygen and nitrate), and
temperature in the overlying water layer. Sediment oxygen demand is controlled
by dissolved oxygen concentrations and temperature in the water layer overlying
the sediments. We used a ‘trial and error’ approach to estimate parameters for
calibrating and validating the model, and regression modelling to infer the parameters beyond the calibration/validation simulation period (2001–2009). We
observed a significant relationship in historic monitoring data between the
external nitrogen load to the lake and its hypolimnetic oxygen demand as well as
the bottom-sediment nitrogen concentrations. This relationship was used to
hindcast and forecast model parameters for sediment nutrient release and oxygen
demand in the six model simulation periods. The inclusion of a dynamic
response of sediment nutrient release and oxygen demand parameters to changes
in external nutrient loads enabled a more conceptually concise simulation of
water quality for the simulations. This model is currently being used by regional
environmental management authorities for developing an Action Plan for the
restoration of Lake Rotorua. | |
dc.description.peerreviewed | Yes | |
dc.language | English | |
dc.language.iso | eng | |
dc.publisher | WIT Press | |
dc.relation.ispartofpagefrom | 171 | |
dc.relation.ispartofpageto | 182 | |
dc.relation.ispartofjournal | WIT Transactions on Ecology and the Environment | |
dc.relation.ispartofvolume | 164 | |
dc.subject.fieldofresearch | Geochemistry not elsewhere classified | |
dc.subject.fieldofresearchcode | 370399 | |
dc.title | Parameterisation of sediment geochemistry for simulating water quality responses to long-term catchment and climate changes in polymictic, eutrophic Lake Rotorua, New Zealand | |
dc.type | Journal article | |
dc.type.description | C1 - Articles | |
dc.type.code | C - Journal Articles | |
dc.description.version | Version of Record (VoR) | |
gro.rights.copyright | © 2012 WIT Press. The attached file is reproduced here in accordance with the copyright policy of the publisher. Please refer to the journal's website for access to the definitive, published version. | |
gro.hasfulltext | Full Text | |
gro.griffith.author | Hamilton, David P. | |