title: Ecological modelling of water quality management options in Lake Waahi to support Hauanga Kai species: Technical Report

authors: Allan, Mathew Grant

abstract: This report describes a numerical modelling approach for Lake Waahi to assess the effects of various future scenarios on water quality attributes known to affect the appearance of the lake’s multiple hauanga kai species across differing spatial scales. Hauanga kai refers to customary gathering and use of naturally occurring and cultivated foods. Numerical models were used to support shared learning and development of future scenarios in response to different management options and environmental pressures. The shallow lakes of the Waikato region have been particularly impacted by anthropogenic eutrophication. This is due to the fact that many of these lakes have already undergone a degree of natural eutrophication due to their geomorphic properties, such as their low elevation and shallow depth. The main contributing factors to water quality decline in shallow Waikato lakes have been identified as: high external nutrient and sediment loads, internal loading exacerbated by high sediment resuspension and bioturbation from pest fish (carp), reduced water depth due to installation of water control structures, reduction in wetland filtering potential due to draining, and stock access to wetlands. A 1-D hydrodynamics model, the General Ocean Turbulence Model was coupled to a complex ecological model (PClake) via the Framework for Aquatic Biogeochemical Models (FABM). FABM is an open source FORTAN-based code that facilitates the coupling of hydrodynamic and ecological models. FABM-PCLake is a redesigned PCLake. The consensus from the model simulations carried out in the study suggests that, for Lake Waahi to undergo restoration whereby the lake is restored to clear-water stable state, both external load needs to be reduced significantly by greater than 50%, along with changes in lake ecological structure, resulting from re-establishment of macrophytes aided by the control of carp biomass. These finding supports the general view within the literature that for lake restoration success, external load reduction (catchment load) is critical. Finally, if the ultimate goal of lake restoration in Lake Waahi is to address the decline in tuna (shortfin eel - Anguilla australis) biomass, a return to a clear-water stable state should facilitate improvement in tuna habitat and provide the conditions for development of a healthy eel population. Coupled modelling approaches will provide a more complete picture of potential responses of Hauanga kai species to land and lake management scenarios.

text: Ecological modelling of water quality management options in Lake Waahi to support Hauanga Kai species: Technical Report This report describes a numerical modelling approach for Lake Waahi to assess the effects of various future scenarios on water quality attributes known to affect the appearance of the lake’s multiple hauanga kai species across differing spatial scales. Hauanga kai refers to customary gathering and use of naturally occurring and cultivated foods. Numerical models were used to support shared learning and development of future scenarios in response to different management options and environmental pressures. The shallow lakes of the Waikato region have been particularly impacted by anthropogenic eutrophication. This is due to the fact that many of these lakes have already undergone a degree of natural eutrophication due to their geomorphic properties, such as their low elevation and shallow depth. The main contributing factors to water quality decline in shallow Waikato lakes have been identified as: high external nutrient and sediment loads, internal loading exacerbated by high sediment resuspension and bioturbation from pest fish (carp), reduced water depth due to installation of water control structures, reduction in wetland filtering potential due to draining, and stock access to wetlands. A 1-D hydrodynamics model, the General Ocean Turbulence Model was coupled to a complex ecological model (PClake) via the Framework for Aquatic Biogeochemical Models (FABM). FABM is an open source FORTAN-based code that facilitates the coupling of hydrodynamic and ecological models. FABM-PCLake is a redesigned PCLake. The consensus from the model simulations carried out in the study suggests that, for Lake Waahi to undergo restoration whereby the lake is restored to clear-water stable state, both external load needs to be reduced significantly by greater than 50%, along with changes in lake ecological structure, resulting from re-establishment of macrophytes aided by the control of carp biomass. These finding supports the general view within the literature that for lake restoration success, external load reduction (catchment load) is critical. Finally, if the ultimate goal of lake restoration in Lake Waahi is to address the decline in tuna (shortfin eel - Anguilla australis) biomass, a return to a clear-water stable state should facilitate improvement in tuna habitat and provide the conditions for development of a healthy eel population. Coupled modelling approaches will provide a more complete picture of potential responses of Hauanga kai species to land and lake management scenarios.

year: 2018

title: Early French views of the Waikato and its inhabitants (1840-54)

authors: Jennings, William

abstract: This paper will investigate how the cultural background of these Frenchmen informed their descriptions of Waikato Maori and the Waikato environment. It will use the newly-published ten-volume collected correspondence of the pioneer Marists in the Pacific,the Lettres refues d'Odanie, as its principal source.

text: Early French views of the Waikato and its inhabitants (1840-54) This paper will investigate how the cultural background of these Frenchmen informed their descriptions of Waikato Maori and the Waikato environment. It will use the newly-published ten-volume collected correspondence of the pioneer Marists in the Pacific,the Lettres refues d'Odanie, as its principal source.

year: 2011

title: Notes: an experiment in CSCW

authors: Apperley, Mark

subjects: computer science

abstract: Computer Supported Co-operative Work (CSCW) systems are complex, yet no computer-based tools of any sophistication exist to support their development. Since several people often need to work together on the same project simultaneously, the computer system often proves to be a bottleneck. CSCW tools are a means of allowing several users to work towards their goal. Systems development is essentially a team process, yet support for CSCW on these systems is in its infancy.

text: Notes: an experiment in CSCW Computer Supported Co-operative Work (CSCW) systems are complex, yet no computer-based tools of any sophistication exist to support their development. Since several people often need to work together on the same project simultaneously, the computer system often proves to be a bottleneck. CSCW tools are a means of allowing several users to work towards their goal. Systems development is essentially a team process, yet support for CSCW on these systems is in its infancy.

year: 1996-04