title: Habitat characteristics of geothermally influenced waters in the Waikato

authors: Stevens, Mark I.

abstract: The Waikato province contains almost 80% of New Zealand's geothermal systems (Environment Waikato 1998). Thus, this region represents an important resource in terms of the habitat associated with increased soil and water temperatures for both geothermal vegetation (Beadel & Bill 2000) and aquatic organisms (Parkyn & Boothroyd 200; Duggan & Boothroyd 2001). Associated issues and values range from exploitative resource use, such as thermal energy extraction and the utilisation of mineralised fluids, to historical, amenity, cultural, spiritual, conservation and scientific values (Environment Waikato 1998; Merrett & Clarkson 1999). The environmental management objectives of Environment Eaikato are derived from these. The objectives are to maintain the variety of characteristics and to achieve protection and efficient of the regional geothermal resource (Environment Waikato 1998).

The present report provides an inventory of the ecological and physical/chemical characteristics of geothermally influenced water in the Waikato province. The area was surveyed between April 10th and May 9th and assessments of habitat and in situ measurement of environmental parameters (eg DO, pH, conductivity, temperature) were used to determine habitat characteristics.

text: Habitat characteristics of geothermally influenced waters in the Waikato The Waikato province contains almost 80% of New Zealand's geothermal systems (Environment Waikato 1998). Thus, this region represents an important resource in terms of the habitat associated with increased soil and water temperatures for both geothermal vegetation (Beadel & Bill 2000) and aquatic organisms (Parkyn & Boothroyd 200; Duggan & Boothroyd 2001). Associated issues and values range from exploitative resource use, such as thermal energy extraction and the utilisation of mineralised fluids, to historical, amenity, cultural, spiritual, conservation and scientific values (Environment Waikato 1998; Merrett & Clarkson 1999). The environmental management objectives of Environment Eaikato are derived from these. The objectives are to maintain the variety of characteristics and to achieve protection and efficient of the regional geothermal resource (Environment Waikato 1998).

The present report provides an inventory of the ecological and physical/chemical characteristics of geothermally influenced water in the Waikato province. The area was surveyed between April 10th and May 9th and assessments of habitat and in situ measurement of environmental parameters (eg DO, pH, conductivity, temperature) were used to determine habitat characteristics.

year: 2003-06

title: Methodological limitations in the evaluation of policies to reduce nitrate leaching from New Zealand agriculture

authors: Doole, Graeme J.

subjects: calibration

abstract: The land-use optimisation framework, NZFARM, has been promoted as a tool that can be used to assess the economic and environmental impacts of policy on regional land use. This paper outlines how methodological limitations presently restrict its capacity to provide meaningful insight into the relative value of alternative land-use configurations. The model is calibrated using positive mathematical programming, which has been shown in the literature to result in models that yield arbitrary output outside of the calibrated baseline. There is a high likelihood that this is the case, as no validation appears to have been carried out. Significant model development will be required before NZFARM outputs can be used with any confidence to inform future policy development. We conclude with suggestions on how NZFARM and models of its kind can be further developed to improve their capacity for meaningful simulation.

text: Methodological limitations in the evaluation of policies to reduce nitrate leaching from New Zealand agriculture The land-use optimisation framework, NZFARM, has been promoted as a tool that can be used to assess the economic and environmental impacts of policy on regional land use. This paper outlines how methodological limitations presently restrict its capacity to provide meaningful insight into the relative value of alternative land-use configurations. The model is calibrated using positive mathematical programming, which has been shown in the literature to result in models that yield arbitrary output outside of the calibrated baseline. There is a high likelihood that this is the case, as no validation appears to have been carried out. Significant model development will be required before NZFARM outputs can be used with any confidence to inform future policy development. We conclude with suggestions on how NZFARM and models of its kind can be further developed to improve their capacity for meaningful simulation.

year: 2013

title: Physical and chemical attributes affecting survival and collection of freshwater mahinga kai species

authors: Collier, Kevin J.

abstract: Mahinga kai is one of a number of significant Māori values identified within the National Objectives Framework (NOF) for freshwater management. The Ngā Tohu o Te Taiao (NToTT) project aimed to develop knowledge, tools and processes for setting freshwater limits for mahinga kai within the NOF. Māori have raised issues and concerns about mahinga kai species due to: (i) declines in abundance, size and quality; and (ii) potential contamination from anthropogenic activities. This review provides information about the contaminants and environmental stressors likely to be affecting some important freshwater mahinga kai, with a focus on tuna (eel), īnanga (whitebait), kākahi (freshwater mussel), kōura (freshwater crayfish) and wātakirihi (watercress). In this report, we provide guidance on how to relate existing guidelines and regulations to freshwater invertebrate and fish species traditionally used for food gathering. The guidance covered includes: (i) the ANZECC (2000) water quality guidelines for physical and chemical attributes of aquatic life, which are in the process of being updated; (ii) selected international water quality guidelines (e.g., USEPA, Environment Canada, OECD) which can be used to support and supplement ANZECC water quality guidelines; (iii) human health information for collection and consumption of aquatic foods; and (iv) the National Policy Statement for Freshwater Management (NPS-FM) and the NOF (which is also under further development). It is envisaged this report will support discussion on food abundance and safety of mahinga kai, and promote steps to ensure appropriate standards are set for clean waterways and customary resources under the NPS-FM and ANZECC (2000). We highlight the complexity of issues affecting abundance and suitability of five commonly-used mahinga kai species: tuna, īnanga, kōura, kākahi and wātakirihi. Information from this report should also be of use in future freshwater habitat and species restoration projects, especially where mahinga kai species are at risk and the goal is to maintain or enhance customary resource use, and species state and condition.

text: Physical and chemical attributes affecting survival and collection of freshwater mahinga kai species Mahinga kai is one of a number of significant Māori values identified within the National Objectives Framework (NOF) for freshwater management. The Ngā Tohu o Te Taiao (NToTT) project aimed to develop knowledge, tools and processes for setting freshwater limits for mahinga kai within the NOF. Māori have raised issues and concerns about mahinga kai species due to: (i) declines in abundance, size and quality; and (ii) potential contamination from anthropogenic activities. This review provides information about the contaminants and environmental stressors likely to be affecting some important freshwater mahinga kai, with a focus on tuna (eel), īnanga (whitebait), kākahi (freshwater mussel), kōura (freshwater crayfish) and wātakirihi (watercress). In this report, we provide guidance on how to relate existing guidelines and regulations to freshwater invertebrate and fish species traditionally used for food gathering. The guidance covered includes: (i) the ANZECC (2000) water quality guidelines for physical and chemical attributes of aquatic life, which are in the process of being updated; (ii) selected international water quality guidelines (e.g., USEPA, Environment Canada, OECD) which can be used to support and supplement ANZECC water quality guidelines; (iii) human health information for collection and consumption of aquatic foods; and (iv) the National Policy Statement for Freshwater Management (NPS-FM) and the NOF (which is also under further development). It is envisaged this report will support discussion on food abundance and safety of mahinga kai, and promote steps to ensure appropriate standards are set for clean waterways and customary resources under the NPS-FM and ANZECC (2000). We highlight the complexity of issues affecting abundance and suitability of five commonly-used mahinga kai species: tuna, īnanga, kōura, kākahi and wātakirihi. Information from this report should also be of use in future freshwater habitat and species restoration projects, especially where mahinga kai species are at risk and the goal is to maintain or enhance customary resource use, and species state and condition.

year: 2017