title: The financial costs of environmental compliance through reducing nitrate leaching for a range of Waikato dairy farm system intensities

authors: Macdonald, Thomas Owen

subjects: Dairy

abstract: The New Zealand dairy industry has grown significantly over the past decade through increasing both area farmed and the number of cows milked.  Dairy farm systems have intensified as a result of the use of supplementary feeding, increased stocking rate and land use changes. Environmental regulations have been implemented as a means to limit and mitigate the negative environmental impacts of dairy under the National Policy Statement for Fresh Water. In the Waikato, regulation to date has predominatly been focused on effluent storage and application. As such, regulation has not yet shaped how Waikato farm systems are implemented. It is likely that future regulation for the Waikato will include nitrogen loss limits. Management of nutrient cycles will therefore become a high priority for effective farm management as well as being used to inform the adoption of changes to farming systems.
Four nitrogen (N) loss mitigation strategies were modelled for Waikato dairy farm systems of low, medium and high input to show the changes in N leaching and economic farm surplus per hectare. Reductions in N leaching for farm environmental compliance were able to be achieved through farm management practices as well as through additional farm infrastructure. Large reductions of 20 percent and 17 percent were achieved through destocking and cow housing scenarios respectively. A corresponding lift in farm surplus per hectare of 1 percent and 11 percent was recorded. Similarly, moderate reductions in N leaching were achieved through winter grazing off farm (9 percent) and increased effluent management facilities (8 percent). However a 4 percent reduction in farm surplus was noted for the winter grazing scenario while increasing the effluent area had no material impact on farm working expenses or revenue. 
This research identified cow housing as farm infrastructure which for low, medium and high input farm systems was able to return a reduction in N leaching greater than 15 percent and increase farm surplus by greater than 9 percent. 
The implementation of cow housing was modelled for a large scale farm system in the Taharua catchment where N limits are currently being enforced. Results of the modelling show a cow housing facility for large scale dairy farming has a positive internal rate of return of 13 percent. 
Waikato dairy farmers were surveyed to gather data on the initial capital cost of compliance and the farm system implications of increased regulation to date. The survey illustrated that effluent compliance has been the focus of investment and highlights the significant cost to the dairy industry of internalising environmental impacts. Aggregated survey results indicate that the capital cost of environmental spending to date for the average Waikato farm system has totaled $1.02 per kgMS, $1487 per hectare or $404 per cow. This equates to an average investment of $110,000 per farm.
A clear understanding of the impact of environmental regulation and the relative cost of compliance for different farm systems is needed to produce accurate measures of environmental performance and to improve the cost efficiency of dairy production systems. Importantly there is a need to understand how different farming systems can work together at a catchment, regional and national level to achieve both value creation and environmental sustainability as set out in the national policy frameworks.

text: The financial costs of environmental compliance through reducing nitrate leaching for a range of Waikato dairy farm system intensities The New Zealand dairy industry has grown significantly over the past decade through increasing both area farmed and the number of cows milked.  Dairy farm systems have intensified as a result of the use of supplementary feeding, increased stocking rate and land use changes. Environmental regulations have been implemented as a means to limit and mitigate the negative environmental impacts of dairy under the National Policy Statement for Fresh Water. In the Waikato, regulation to date has predominatly been focused on effluent storage and application. As such, regulation has not yet shaped how Waikato farm systems are implemented. It is likely that future regulation for the Waikato will include nitrogen loss limits. Management of nutrient cycles will therefore become a high priority for effective farm management as well as being used to inform the adoption of changes to farming systems.
Four nitrogen (N) loss mitigation strategies were modelled for Waikato dairy farm systems of low, medium and high input to show the changes in N leaching and economic farm surplus per hectare. Reductions in N leaching for farm environmental compliance were able to be achieved through farm management practices as well as through additional farm infrastructure. Large reductions of 20 percent and 17 percent were achieved through destocking and cow housing scenarios respectively. A corresponding lift in farm surplus per hectare of 1 percent and 11 percent was recorded. Similarly, moderate reductions in N leaching were achieved through winter grazing off farm (9 percent) and increased effluent management facilities (8 percent). However a 4 percent reduction in farm surplus was noted for the winter grazing scenario while increasing the effluent area had no material impact on farm working expenses or revenue. 
This research identified cow housing as farm infrastructure which for low, medium and high input farm systems was able to return a reduction in N leaching greater than 15 percent and increase farm surplus by greater than 9 percent. 
The implementation of cow housing was modelled for a large scale farm system in the Taharua catchment where N limits are currently being enforced. Results of the modelling show a cow housing facility for large scale dairy farming has a positive internal rate of return of 13 percent. 
Waikato dairy farmers were surveyed to gather data on the initial capital cost of compliance and the farm system implications of increased regulation to date. The survey illustrated that effluent compliance has been the focus of investment and highlights the significant cost to the dairy industry of internalising environmental impacts. Aggregated survey results indicate that the capital cost of environmental spending to date for the average Waikato farm system has totaled $1.02 per kgMS, $1487 per hectare or $404 per cow. This equates to an average investment of $110,000 per farm.
A clear understanding of the impact of environmental regulation and the relative cost of compliance for different farm systems is needed to produce accurate measures of environmental performance and to improve the cost efficiency of dairy production systems. Importantly there is a need to understand how different farming systems can work together at a catchment, regional and national level to achieve both value creation and environmental sustainability as set out in the national policy frameworks.

year: 2014

title: Stratigraphy and sedimentology of Pliocene limestones, Wairoa district, northern Hawke's Bay

authors: Jiang, Zichun (Jared)

subjects: Pliocene limestones

abstract: This project documents the sedimentary geology of a shallow-marine, limestone-bearing Pliocene succession (Mangaheia Group; up to 1.5 km thick) within the Wairoa Syncline, northern Hawke’s Bay. The primary focus is three cool-water “Te Aute type” limestone units in the succession – the early Opoitian age Opoiti Limestone (5-10 m thick), the late Opoitian age Whakapunake Limestone (30-100m thick) and the Waipipian age Tahaenui Limestone (10-30 m thick) – that form locally spectacular outcrops in the Wairoa district. Lithostratigraphically, the limestones are given formational status while the encasing siliciclastic sandstones and mudstones are lumped into a newly defined Wairoa Formation which can be informally classified as A, B, C or D depending on position with respect to the three limestone formations. Three field lithofacies groups – limestone (L), sandstone (S) and mudstone (M) – are erected, and variability within these groups is recognised by subdivision into three lithofacies types, L1-3, S1-3 and M1-3. The massive Opoiti Limestone (35-65% CaCO₃; L3 and S2) comprises poorly sorted, variably sandy, barnacle, epifaunal bivalve and locally brachiopod debris well-cemented by low-Mg calcite (LMC) (micro)sparite and micrite. Opoiti Limestone is a bioclastic quartzofeldspathic arenite to biosparrudite, occasionally dolomite-bearing. Occasional calcite infilled biomoulds are testament to former aragonite molluscan skeletons. Opoiti Limestone unconformably overlies Wairoa Formation A (2-200 m thick), and grades up into differentially cemented mudstone of Wairoa Formation B (700-800 m thick) which is unconformably overlain by Whakapunake Limestone. The late Opoitian Whakapunake Limestone (up to 85% CaCO₃; L1, L2 and S1) comprises (cross) bedded and differentially cemented interbeds of fossiliferous and more siliciclastic-rich facies. The limestones are typically poorly sorted bivalve-barnacle biomicrite to biosparrudite cemented by variable amounts of fringe and later equant LMC (micro)spar, sometimes including abundant zoned stoichiometric dolomite rhombohedra. Fabrics are moderately open to tight with some conspicuous limonitised glauconite. Whakapunake Limestone passes conformably up into massive calcareous mudstone of Wairoa Formation C (latest Opoitian; >10 m thick). A shallow angular unconformity separates the Whakapunake Limestone and/or Wairoa Formation C from the overlying well-cemented flaggy Tahaenui Limestone (50-80% CaCO₃; L1), a bivalve-barnacle biosparite to biosparrudite with some neomorphosed former aragonite skeletons and a moderately open fabric. In this limestone early formed dull luminescent isopachous fringing cements (host specific) precede variable pore occlusion by dirty LMC (micro)spar and/or micrite. 
The three limestone formations accumulated on the eastern side of a narrow forearc basin seaway (Ruataniwha Strait) within the Hikurangi subduction complex atop and about antiform upthrust ridges in an active convergent margin setting. Tectonics was the main control on the location and mainly lensoidal geometry of the limestone units, while Pliocene glacioeustatic sea-level fluctuations played a secondary role. Cross-bedded and interbedded limestonesandstone facies attest to deposition under the influence of strong tidal flows and repeated storm events that produced high-energy hydraulic conditions and reworking of variably mixed terrigenous-skeletal sands in the shallow (<30 m) seaway during Pliocene. Redeposition down flank from antiform summits provided accommodation space for sediment build-up.
The calcite dominated cool-water skeletal make-up of these limestones, combined with their relatively shallow burial depths (150-700 m), has resulted in them retaining significant macroporosity (up to 20%). Consequently, as well as having application as a lime or hard rock resource they also have reservoir potential for hydrocarbons in the subsurface.

text: Stratigraphy and sedimentology of Pliocene limestones, Wairoa district, northern Hawke's Bay This project documents the sedimentary geology of a shallow-marine, limestone-bearing Pliocene succession (Mangaheia Group; up to 1.5 km thick) within the Wairoa Syncline, northern Hawke’s Bay. The primary focus is three cool-water “Te Aute type” limestone units in the succession – the early Opoitian age Opoiti Limestone (5-10 m thick), the late Opoitian age Whakapunake Limestone (30-100m thick) and the Waipipian age Tahaenui Limestone (10-30 m thick) – that form locally spectacular outcrops in the Wairoa district. Lithostratigraphically, the limestones are given formational status while the encasing siliciclastic sandstones and mudstones are lumped into a newly defined Wairoa Formation which can be informally classified as A, B, C or D depending on position with respect to the three limestone formations. Three field lithofacies groups – limestone (L), sandstone (S) and mudstone (M) – are erected, and variability within these groups is recognised by subdivision into three lithofacies types, L1-3, S1-3 and M1-3. The massive Opoiti Limestone (35-65% CaCO₃; L3 and S2) comprises poorly sorted, variably sandy, barnacle, epifaunal bivalve and locally brachiopod debris well-cemented by low-Mg calcite (LMC) (micro)sparite and micrite. Opoiti Limestone is a bioclastic quartzofeldspathic arenite to biosparrudite, occasionally dolomite-bearing. Occasional calcite infilled biomoulds are testament to former aragonite molluscan skeletons. Opoiti Limestone unconformably overlies Wairoa Formation A (2-200 m thick), and grades up into differentially cemented mudstone of Wairoa Formation B (700-800 m thick) which is unconformably overlain by Whakapunake Limestone. The late Opoitian Whakapunake Limestone (up to 85% CaCO₃; L1, L2 and S1) comprises (cross) bedded and differentially cemented interbeds of fossiliferous and more siliciclastic-rich facies. The limestones are typically poorly sorted bivalve-barnacle biomicrite to biosparrudite cemented by variable amounts of fringe and later equant LMC (micro)spar, sometimes including abundant zoned stoichiometric dolomite rhombohedra. Fabrics are moderately open to tight with some conspicuous limonitised glauconite. Whakapunake Limestone passes conformably up into massive calcareous mudstone of Wairoa Formation C (latest Opoitian; >10 m thick). A shallow angular unconformity separates the Whakapunake Limestone and/or Wairoa Formation C from the overlying well-cemented flaggy Tahaenui Limestone (50-80% CaCO₃; L1), a bivalve-barnacle biosparite to biosparrudite with some neomorphosed former aragonite skeletons and a moderately open fabric. In this limestone early formed dull luminescent isopachous fringing cements (host specific) precede variable pore occlusion by dirty LMC (micro)spar and/or micrite. 
The three limestone formations accumulated on the eastern side of a narrow forearc basin seaway (Ruataniwha Strait) within the Hikurangi subduction complex atop and about antiform upthrust ridges in an active convergent margin setting. Tectonics was the main control on the location and mainly lensoidal geometry of the limestone units, while Pliocene glacioeustatic sea-level fluctuations played a secondary role. Cross-bedded and interbedded limestonesandstone facies attest to deposition under the influence of strong tidal flows and repeated storm events that produced high-energy hydraulic conditions and reworking of variably mixed terrigenous-skeletal sands in the shallow (<30 m) seaway during Pliocene. Redeposition down flank from antiform summits provided accommodation space for sediment build-up.
The calcite dominated cool-water skeletal make-up of these limestones, combined with their relatively shallow burial depths (150-700 m), has resulted in them retaining significant macroporosity (up to 20%). Consequently, as well as having application as a lime or hard rock resource they also have reservoir potential for hydrocarbons in the subsurface.

year: 2011

title: Characteristics and outcomes of patients with small cell lung cancer - findings from a New Zealand SACT database

authors: Lawrenson, Ross

abstract: Background Small Cell Lung Cancer (SCLC) SCLC generally presents late and is treated with systemic anti-cancer treatment (SACT). Māori are over represented in Lung Cancer statistics but disparities between Māori and non-Māori in patterns of care and survival from SCLC have not been previously reported. 
Methods We used the custom-built SACT database collected by the Oncology Department at Waikato Hospital NZ, which recorded comprehensive lung cancer patient factors and SACT regimens from 2000 to 2021. We reported summary statistics to review the treatment by ethnicity, explored Kaplan Meier all-cause survival of patients, and estimated the unadjusted and adjusted odds ratios of surviving 12 months. 
Results 742 patients with SCLC were included in this study, with 43% identified as Māori. Approximately 75% of patients received SACT, and there was no difference in the uptake of SACT between Māori and non-Māori. The median survival for SCLC was 8.5 months. After adjustment, patients treated with carboplatin plus etoposide (with/without durvalumab) or cisplatin plus etoposide were 1.5 times or 4.9 times respectively more likely to survive 12 months than those without a SACT regimen.
Conclusion There was no significant evidence of disparities in patterns of care and outcomes between Māori and non-Māori with SCLC. Carboplatin/cisplatin in combination with etoposide remained the primary first line SACT regimen for patients with SCLC in this New Zealand cancer treatment centre.

text: Characteristics and outcomes of patients with small cell lung cancer - findings from a New Zealand SACT database Background Small Cell Lung Cancer (SCLC) SCLC generally presents late and is treated with systemic anti-cancer treatment (SACT). Māori are over represented in Lung Cancer statistics but disparities between Māori and non-Māori in patterns of care and survival from SCLC have not been previously reported. 
Methods We used the custom-built SACT database collected by the Oncology Department at Waikato Hospital NZ, which recorded comprehensive lung cancer patient factors and SACT regimens from 2000 to 2021. We reported summary statistics to review the treatment by ethnicity, explored Kaplan Meier all-cause survival of patients, and estimated the unadjusted and adjusted odds ratios of surviving 12 months. 
Results 742 patients with SCLC were included in this study, with 43% identified as Māori. Approximately 75% of patients received SACT, and there was no difference in the uptake of SACT between Māori and non-Māori. The median survival for SCLC was 8.5 months. After adjustment, patients treated with carboplatin plus etoposide (with/without durvalumab) or cisplatin plus etoposide were 1.5 times or 4.9 times respectively more likely to survive 12 months than those without a SACT regimen.
Conclusion There was no significant evidence of disparities in patterns of care and outcomes between Māori and non-Māori with SCLC. Carboplatin/cisplatin in combination with etoposide remained the primary first line SACT regimen for patients with SCLC in this New Zealand cancer treatment centre.

year: 2023-02-10