title: A coupled hydrodynamic-ecological model to test management options for restoration of lakes Onoke and Wairarapa

authors: Allan, Mathew Grant

abstract: This report describes a modelling and remote sensing study of lakes Onoke and Wairarapa that seeks to determine water quality and ecological effects of specific management scenarios, and therefore inform the Ruamāhanga Whaitua Committee of potential water quality management options for lakes Onoke and Wairarapa.
The study applied both one dimensional (1-D) and three dimensional (3-D) ecologically coupled hydrodynamic models to simulate current and scenario-based water quality variables. The Baseline model (calibration) simulates “current conditions” including management practices between 1992 and 2014. Business As Usual (BAU), SILVER and GOLD scenarios were all run using representative data catchment inflow and nutrients for mitigation taking effect in 2025, 2040 and 2080. Additional hydrodynamic scenarios were modelled (which also include catchment mitigations above). They were: deepening both lakes by 1 m, Ruamāhanga diversion back into Lake Wairarapa, and Lake Onoke summer outlet closed scenarios. These scenarios were provided by the Ruamāhanga Whaitua Committee.
Within Lake Wairarapa, catchment mitigation-based scenarios showed considerable potential for the improvement of water quality. These mitigations simulated that the trophic state of the lake could change from the current supertrophic category, to the top of the eutrophic category (GOLD and SILVER mitigations). However, this still indicates poor water quality and high turbidity/low water clarity. In addition, these catchment mitigations did not move the lake from a NOF D category for total phosphorous (TP). Simulations indicated that larger reductions in TP (60%) (with SILVER2080 mitigations of other nutrients) could achieve a NOF C category for TP. Simulations that included the re-establishment of macrophytes also indicated NOF C category for TP (under SILVER2080), however only under a 1 m depth increase scenario, and under Ruamāhanga diversion scenario. These simulations indicated that the trophic status could move to the mid-eutrophic category. However, this is still indicative of poor water quality.
Catchment scenarios had a greater influence on Lake Onoke trophic status compared to Wairarapa, due to the shorter residence time and low internal load (from the sediments) relative to external load. In effect, the composition of Onoke aligns closely with that of its inflows. Water quality in Lake Onoke is susceptible to changes in water quality in Lake Wairarapa, particularly in relation to chlorophyll a (chl a) and total suspended solids (TSS). High sediment resuspension events in Lake Wairarapa transport increased levels of suspended sediment to Lake Onoke. The very low residence time in Onoke does not allow adequate time for significant phytoplankton growth within the lake. However, 3-D simulations show higher phytoplankton concentrations at times in the western lake, relating to flushing and transport effects. The outlet-closed scenario in Lake Onoke simulated increased water quality in both 1-D and 3-D models However, we note that the risk of cyanobacteria blooms was low, but marginally increased. Also 1-D models suggested that the simulated TLI under SILVER2080 was almost identical to outlet closed SILVER2080. The 3-D model simulated lower chlorophyll concentrations and higher TSS under SILVER2080 outlet closed (compared to SILVER2080 and Baseline), largely due to changes in hydrodynamics and flushing. Therefore, these results show no conclusive evidence that water quality would be significantly increased or decreased in comparison to SILVER2080 under an outlet closed scenario. However, we note that in situ monitoring and expert opinion has indicated that under outlet closed conditions the lake is more susceptible to eutrophication.

text: A coupled hydrodynamic-ecological model to test management options for restoration of lakes Onoke and Wairarapa This report describes a modelling and remote sensing study of lakes Onoke and Wairarapa that seeks to determine water quality and ecological effects of specific management scenarios, and therefore inform the Ruamāhanga Whaitua Committee of potential water quality management options for lakes Onoke and Wairarapa.
The study applied both one dimensional (1-D) and three dimensional (3-D) ecologically coupled hydrodynamic models to simulate current and scenario-based water quality variables. The Baseline model (calibration) simulates “current conditions” including management practices between 1992 and 2014. Business As Usual (BAU), SILVER and GOLD scenarios were all run using representative data catchment inflow and nutrients for mitigation taking effect in 2025, 2040 and 2080. Additional hydrodynamic scenarios were modelled (which also include catchment mitigations above). They were: deepening both lakes by 1 m, Ruamāhanga diversion back into Lake Wairarapa, and Lake Onoke summer outlet closed scenarios. These scenarios were provided by the Ruamāhanga Whaitua Committee.
Within Lake Wairarapa, catchment mitigation-based scenarios showed considerable potential for the improvement of water quality. These mitigations simulated that the trophic state of the lake could change from the current supertrophic category, to the top of the eutrophic category (GOLD and SILVER mitigations). However, this still indicates poor water quality and high turbidity/low water clarity. In addition, these catchment mitigations did not move the lake from a NOF D category for total phosphorous (TP). Simulations indicated that larger reductions in TP (60%) (with SILVER2080 mitigations of other nutrients) could achieve a NOF C category for TP. Simulations that included the re-establishment of macrophytes also indicated NOF C category for TP (under SILVER2080), however only under a 1 m depth increase scenario, and under Ruamāhanga diversion scenario. These simulations indicated that the trophic status could move to the mid-eutrophic category. However, this is still indicative of poor water quality.
Catchment scenarios had a greater influence on Lake Onoke trophic status compared to Wairarapa, due to the shorter residence time and low internal load (from the sediments) relative to external load. In effect, the composition of Onoke aligns closely with that of its inflows. Water quality in Lake Onoke is susceptible to changes in water quality in Lake Wairarapa, particularly in relation to chlorophyll a (chl a) and total suspended solids (TSS). High sediment resuspension events in Lake Wairarapa transport increased levels of suspended sediment to Lake Onoke. The very low residence time in Onoke does not allow adequate time for significant phytoplankton growth within the lake. However, 3-D simulations show higher phytoplankton concentrations at times in the western lake, relating to flushing and transport effects. The outlet-closed scenario in Lake Onoke simulated increased water quality in both 1-D and 3-D models However, we note that the risk of cyanobacteria blooms was low, but marginally increased. Also 1-D models suggested that the simulated TLI under SILVER2080 was almost identical to outlet closed SILVER2080. The 3-D model simulated lower chlorophyll concentrations and higher TSS under SILVER2080 outlet closed (compared to SILVER2080 and Baseline), largely due to changes in hydrodynamics and flushing. Therefore, these results show no conclusive evidence that water quality would be significantly increased or decreased in comparison to SILVER2080 under an outlet closed scenario. However, we note that in situ monitoring and expert opinion has indicated that under outlet closed conditions the lake is more susceptible to eutrophication.

year: 2018

title: Injection-Molding Performance and Mechanical Properties of Blood Meal-Based Thermoplastics

authors: Adamy, Maximilian

subjects: biodegradable

abstract: Protein-based thermoplastics offer an attractive alternative to petroleum-based plastics if their properties allow for large volume production using processes such as injection molding. A fractional factorial design was used to analyze the influence of injection-molding parameters (melt temperature, tool temperature, injection rate, holding pressure, and cooling time) on the injection-molding process (maximum injection pressure, injection pressure curve) and mechanical properties (tensile strength, elongation at break, secant modulus) of blood meal–based thermoplastics. Optimal mechanical properties were obtained at higher tool and melt temperatures while the injection rate was unimportant. The most important injection parameter was the holding pressure, which has to be lowered when using a higher melt temperature, which was preferred for better elongation at break. A lower holding pressure also produced moldings with a higher modulus, which could be good for demolding. Blood meal–based thermoplastics behaved mostly like standard thermoplastics, without any significant deviations. Within a workable processing window, its mechanical properties were largely unaffected by processing conditions, but as with any thermoplastic, care must be taken to select the best injection-molding parameter settings to achieve optimal part quality and high processability.

text: Injection-Molding Performance and Mechanical Properties of Blood Meal-Based Thermoplastics Protein-based thermoplastics offer an attractive alternative to petroleum-based plastics if their properties allow for large volume production using processes such as injection molding. A fractional factorial design was used to analyze the influence of injection-molding parameters (melt temperature, tool temperature, injection rate, holding pressure, and cooling time) on the injection-molding process (maximum injection pressure, injection pressure curve) and mechanical properties (tensile strength, elongation at break, secant modulus) of blood meal–based thermoplastics. Optimal mechanical properties were obtained at higher tool and melt temperatures while the injection rate was unimportant. The most important injection parameter was the holding pressure, which has to be lowered when using a higher melt temperature, which was preferred for better elongation at break. A lower holding pressure also produced moldings with a higher modulus, which could be good for demolding. Blood meal–based thermoplastics behaved mostly like standard thermoplastics, without any significant deviations. Within a workable processing window, its mechanical properties were largely unaffected by processing conditions, but as with any thermoplastic, care must be taken to select the best injection-molding parameter settings to achieve optimal part quality and high processability.

year: 2013

title: Empowerment evaluation of Te Taiwhenua o Heretaunga Family Start: Improving service delivery

authors: Little, Gaylene Robina

subjects: Family Start

abstract: This thesis explores child maltreatment in New Zealand by considering service delivery of the Family Start programme at Te Taiwhenua o Heretaunga through an empowerment evaluation. The purpose of this research is to evaluate the service delivery process of the Family Start programme at this site to inform the organization and other Family Start key agents of possible improvements to service delivery so that the Family Start programme is best able to reduce the risk factors that are known to influence child maltreatment in New Zealand. The best possible service delivery by kaupapa providers supports sustainability and the continuity of service with Māori through continual funding. The two objectives of this research are to look at how well the Family Start programme is implemented at Te Taiwhenua o Heretaunga and to consider the cultural appropriateness of service delivery. Community psychology is the paradigm within which I position myself. I respect the values of community psychology that aim to improve the position of disadvantaged people through their participation in social change and community development. Te Taiwhenua o Heretaunga is a kaupapa Māori provider and I see an empowerment evaluation as a tool for internal evaluation to assist organizations who value self determination in their own practice. Both quantitative and qualitative data were collected and analyzed. There are two objectives to consider service delivery; firstly process aspects of service delivery are looked at and secondly the cultural relevance of service delivery to the population receiving the Family Start programme at this site. These are described as nine points about service delivery. The aim is to provide an empowerment evaluation for Te Taiwhenua o Heretaunga to inform, assist and improve service delivery of the Family Start programme in a culturally appropriate manner. The findings suggest better understanding is needed by Te Taiwhenua o Heretaunga Family Start staff, about the programme intentions, the use of tools such as Born to Learn/Ahuru Mōwai, individual family plans, service delivery levels, maintaining health records and ways to encourage collaboration between agencies. Te Taiwhenua o Heretaunga are shown in this research to be reaching the intended population for the Family Start programme, and service delivery appears to be culturally relevant to the clients on the programme at this time. The findings are limited by the fact that access to some information was restricted by Te Taiwhenua o Heretaunga Family Start management. Consequently, this research looked only at service delivery, and not the benefits of or barriers to the actual programme. The effectiveness of the programme in reducing child maltreatment is important but could not be measured in this research. Reducing child maltreatment is the main aim of the Family Start programme and would be measured through client outcomes. This research considered service delivery to see if the Family Start programme is offered optimally to assist the aim of reducing child maltreatment.

text: Empowerment evaluation of Te Taiwhenua o Heretaunga Family Start: Improving service delivery This thesis explores child maltreatment in New Zealand by considering service delivery of the Family Start programme at Te Taiwhenua o Heretaunga through an empowerment evaluation. The purpose of this research is to evaluate the service delivery process of the Family Start programme at this site to inform the organization and other Family Start key agents of possible improvements to service delivery so that the Family Start programme is best able to reduce the risk factors that are known to influence child maltreatment in New Zealand. The best possible service delivery by kaupapa providers supports sustainability and the continuity of service with Māori through continual funding. The two objectives of this research are to look at how well the Family Start programme is implemented at Te Taiwhenua o Heretaunga and to consider the cultural appropriateness of service delivery. Community psychology is the paradigm within which I position myself. I respect the values of community psychology that aim to improve the position of disadvantaged people through their participation in social change and community development. Te Taiwhenua o Heretaunga is a kaupapa Māori provider and I see an empowerment evaluation as a tool for internal evaluation to assist organizations who value self determination in their own practice. Both quantitative and qualitative data were collected and analyzed. There are two objectives to consider service delivery; firstly process aspects of service delivery are looked at and secondly the cultural relevance of service delivery to the population receiving the Family Start programme at this site. These are described as nine points about service delivery. The aim is to provide an empowerment evaluation for Te Taiwhenua o Heretaunga to inform, assist and improve service delivery of the Family Start programme in a culturally appropriate manner. The findings suggest better understanding is needed by Te Taiwhenua o Heretaunga Family Start staff, about the programme intentions, the use of tools such as Born to Learn/Ahuru Mōwai, individual family plans, service delivery levels, maintaining health records and ways to encourage collaboration between agencies. Te Taiwhenua o Heretaunga are shown in this research to be reaching the intended population for the Family Start programme, and service delivery appears to be culturally relevant to the clients on the programme at this time. The findings are limited by the fact that access to some information was restricted by Te Taiwhenua o Heretaunga Family Start management. Consequently, this research looked only at service delivery, and not the benefits of or barriers to the actual programme. The effectiveness of the programme in reducing child maltreatment is important but could not be measured in this research. Reducing child maltreatment is the main aim of the Family Start programme and would be measured through client outcomes. This research considered service delivery to see if the Family Start programme is offered optimally to assist the aim of reducing child maltreatment.

year: 2010