title: Framework for evaluating management interventions for water-quality improvement across multiple agents

authors: Doole, Graeme J.

subjects: integrated modelling

abstract: It is difficult to accurately predict the impacts of policies for control of nonpoint-source pollution because analytical frameworks incorporating agent heterogeneity are rare. This paper overcomes this limitation through describing a new framework in which the behaviour of individual firms is explicitly represented by large, complex models calibrated to baseline information. Disaggregation allows the simulation of policies that require uniform reductions in pollutant load or those that allow different rates of abatement between firms to achieve a given nutrient target at least cost, as with the trading of pollution entitlements. The reduction of nitrate leaching from intensive dairy production in a catchment of the Waikato River in New Zealand is used as an illustrative application. It is highlighted that satisfaction of water-quality standards will incur substantial costs within this region. Overall, the framework is notable for its integration of multiple modelling techniques from diverse disciplines and its focus on the behaviour of individual agents. Moreover, it can easily be applied elsewhere where sufficient information is available.

text: Framework for evaluating management interventions for water-quality improvement across multiple agents It is difficult to accurately predict the impacts of policies for control of nonpoint-source pollution because analytical frameworks incorporating agent heterogeneity are rare. This paper overcomes this limitation through describing a new framework in which the behaviour of individual firms is explicitly represented by large, complex models calibrated to baseline information. Disaggregation allows the simulation of policies that require uniform reductions in pollutant load or those that allow different rates of abatement between firms to achieve a given nutrient target at least cost, as with the trading of pollution entitlements. The reduction of nitrate leaching from intensive dairy production in a catchment of the Waikato River in New Zealand is used as an illustrative application. It is highlighted that satisfaction of water-quality standards will incur substantial costs within this region. Overall, the framework is notable for its integration of multiple modelling techniques from diverse disciplines and its focus on the behaviour of individual agents. Moreover, it can easily be applied elsewhere where sufficient information is available.

year: 2011

title: Forecasting seasonal drawdowns in Whangamata town supply wells

authors: Jelley, Neil

subjects: groundwater

abstract: The coastal township of Whangamata's reticulated water supply is provided by a
number of groundwater bores, extracting water from local fractured rhyolite and
andesite aquifers. A need has arisen to create a greater understanding of the aquifers,
because of an increased demand for water abstraction. Water demand in Whangamata
increases dramatically during the summer vacation period. Occupant numbers
increase from 4,000 up to 50,000 during peak times, resulting in increased water
demand. Over the past five years an increase in groundwater abstraction has produced
an evident downward trend in bore water levels. Electrical conductivity is also
increasing in several aquifers, posing a realistic threat of sea water intrusion and
questioning the sustainability of current abstraction volumes.
Multiple linear regression and an artificial neural network model were investigated as
simple empirical forecasting tools for well drawdowns to predict the effect of future
increases in groundwater demand. This approach was adopted as opposed to a
groundwater numerical model because of poor time resolution of available data and
the complex, fractured nature of the aquifer. By using pumping volumes as variables,
seasonal bore water level variations and long term trends were predicted. The models
were evaluated with independent validation data sets. The actual ability of a model to
predict bore water level seasonal variation and long term trends was assessed using a
comparison with a moving average of the validation data set.
Multiple linear regression proved superior to the neural network in almost every bore
modelled. Although neural networks proved capable of modelling seasonal bore
water level variations it was not to the same degree of accuracy as the regression
approach. The regression approach yielded a modified index of agreement of 0.6-0.74
when comparing a moving average of observed data with the validation data sets. The
developed models were used to forecast well water levels with varying abstraction
volumes aiming to prevent further long term decline in bore water levels.

text: Forecasting seasonal drawdowns in Whangamata town supply wells The coastal township of Whangamata's reticulated water supply is provided by a
number of groundwater bores, extracting water from local fractured rhyolite and
andesite aquifers. A need has arisen to create a greater understanding of the aquifers,
because of an increased demand for water abstraction. Water demand in Whangamata
increases dramatically during the summer vacation period. Occupant numbers
increase from 4,000 up to 50,000 during peak times, resulting in increased water
demand. Over the past five years an increase in groundwater abstraction has produced
an evident downward trend in bore water levels. Electrical conductivity is also
increasing in several aquifers, posing a realistic threat of sea water intrusion and
questioning the sustainability of current abstraction volumes.
Multiple linear regression and an artificial neural network model were investigated as
simple empirical forecasting tools for well drawdowns to predict the effect of future
increases in groundwater demand. This approach was adopted as opposed to a
groundwater numerical model because of poor time resolution of available data and
the complex, fractured nature of the aquifer. By using pumping volumes as variables,
seasonal bore water level variations and long term trends were predicted. The models
were evaluated with independent validation data sets. The actual ability of a model to
predict bore water level seasonal variation and long term trends was assessed using a
comparison with a moving average of the validation data set.
Multiple linear regression proved superior to the neural network in almost every bore
modelled. Although neural networks proved capable of modelling seasonal bore
water level variations it was not to the same degree of accuracy as the regression
approach. The regression approach yielded a modified index of agreement of 0.6-0.74
when comparing a moving average of observed data with the validation data sets. The
developed models were used to forecast well water levels with varying abstraction
volumes aiming to prevent further long term decline in bore water levels.

year: 2007

title: Maori seeking self-determination or Tino Rangatiratanga? A note

authors: Toki, Valmaine

abstract: Dr Nin Tomas wrote a considered and substantial piece entitled “Indigenous Peoples and the Māori: The Right to Self-Determination in International Law - From Woe to Go” for the New Zealand Law Review published in 2008.² In her conclusion she notes two ways in which self-determination has been implemented by the state: first, by “greater tolerance and benevolence along a series of principled guidelines”,³ and, second, as a “peoples-centred, enabling principle that allows Indigenous peoples to re-establish their social, economic and political institutions”.⁴
In 2010, New Zealand reversed its position and supported the United Nations Declaration on the Rights of Indigenous Peoples (the Declaration).5 With this in mind, this short piece revisits the notion of self-determination by examining the differing dynamics of concepts of external and internal self-determination before a short discussion on pluralism and the relationship between tino rangatiratanga and self-determination. In conclusion some thoughts are offered on a potential form of self-determination that could be consistent with the exercise of tino rangatiratanga.

text: Maori seeking self-determination or Tino Rangatiratanga? A note Dr Nin Tomas wrote a considered and substantial piece entitled “Indigenous Peoples and the Māori: The Right to Self-Determination in International Law - From Woe to Go” for the New Zealand Law Review published in 2008.² In her conclusion she notes two ways in which self-determination has been implemented by the state: first, by “greater tolerance and benevolence along a series of principled guidelines”,³ and, second, as a “peoples-centred, enabling principle that allows Indigenous peoples to re-establish their social, economic and political institutions”.⁴
In 2010, New Zealand reversed its position and supported the United Nations Declaration on the Rights of Indigenous Peoples (the Declaration).5 With this in mind, this short piece revisits the notion of self-determination by examining the differing dynamics of concepts of external and internal self-determination before a short discussion on pluralism and the relationship between tino rangatiratanga and self-determination. In conclusion some thoughts are offered on a potential form of self-determination that could be consistent with the exercise of tino rangatiratanga.

year: 2017