WISE - Carbon Forestry

Waikato Regional Council (WRC) has developed a ‘Waikato Regional Carbon Forestry – Principles and Framework’ which is aimed at creating and supporting mechanisms through which carbon credits and trading can be used to encourage land use change in the Region.

This report sets out the principles of how the ETS can be utilised at a regional level to encourage forestry plantings and associated environmental benefits.  It also defines how Council can facilitate land use change in a low risk environment that will offer opportunities to landowners who see the advantages of developing a carbon income stream to supplement their pastoral farming revenue or offset ETS liabilities.

WRC wished to use WISE to explore different scenarios based on changes to land use in the region by conversion from existing land use to exotic forestry.


It was hoped WISE could be used to help understand and communicate any potential economic change through carbon farming policy implementation while also potentially improving ecological and environmental indicators. Various economic, environmental and land use indicators were asked to be analysed with the intention of identifying changes over time resulting from the implementation of such a policy when compared against a baseline (status quo) scenario.

The hypothesis was that the clearance of indigenous vegetation and wetlands would halt, and that exotic forest planting would increase, due to the economic value placed on those land uses as carbon sinks. This land use change would in turn have various impacts on the economy and environment of the Waikato Region depending on where, and how much, land use changed across the region.

Two methods were proposed to stimulate forestry and model a halt in the decline of indigenous vegetation and wetlands; Economic demand and the Zoning tool.

Economic demand

It was theorised that a certain increase in demand for forest land would result from an increase in economic demand due to government schemes such as the Permanent Forest Sink Initiative (PFSI), EBEX21 (Landcare Research) or the Emissions Trading Scheme (ETS). Economic demand, and in turn land use demand, can be changed in WISE by adjusting the international and interregional exports in sector parameter over time. Ideally for this scenario a unique carbon farming economic sector would be used but as this does not exist in WISE at this stage (proposed for future development) changes to exports in the Forestry and logging sector were used as a proxy for change resulting from carbon forest sector activity.

Zoning tool

The zoning tool can be used to dictate the RMA zoning/activity status rules (Actively stimulated, Permitted, Controlled, Restricted Discretionary, Discretionary, Non-Complying or Prohibited) that apply to each land use at each location (cell). The zoning tool is also used to set a precedence order to dictate which rules shall apply at which location and also allows the user to define a numerical “probabilistic” value to each zoning/activity status for each land use (default values of 1.2, 1, 0.8, 0.6, 0.4, 0.2 and 0 for each of the above zoning/activity status’ respectively). Using the zoning tool we were able to map locations where land use development would be prohibited, and therefore indigenous vegetation and wetland would be protected, and where forestry would be actively stimulated. We were also able to dictate variations to the strength of that stimulation. These locations varied depending on which scenario, or combination of scenarios, was explored (see below).

Other key variables used in the work were:

  1. That such a policy change might take effect from 2012 to 2050.
  2. That approximately 60,000 to 70,000 additional hectares of forestry might be allocated within the actively stimulated policy area by 2050 as a result of the policy implementation.


A comparison of a number of indicators resulting from the scenarios below against the same indicators resulting from the baseline scenario at the same time was required:

Land use indicators

  1. Map comparison and land use area (ha): Forestry by 2050
  2. Map comparison and land use area (ha): Dairy Farming by 2050
  3. Map comparison and land use area (ha): Sheep, Beef and Deer Farming by 2050
  4. Demand (ha) versus allocation (ha) over time: Forestry
  5. Demand (ha) versus allocation (ha) over time: Dairy Farming
  6. Demand (ha) versus allocation (ha) over time: Sheep, Beef and Deer Farming

Other indicators derived in post-processing

  1. Effective area of possible policy area protecting indigenous vegetation and wetlands (ha): all land use functions
  2. Effective area of possible actively stimulated policy area (ha): Forestry

Environmental indicators

  1. Annual runoff (mm/year) by 2050
  2. Summer flow yield (l/s/km2) by 2050
  3. Phosphorous load (tonnes/year) by 2050 at the following locations:
    1. Piako river mouth
    2. Waihou river mouth
    3. Waikato river mouth
    4. Karapiro Dam
    5. Taupo Gates
    6. Waipa river mouth
    7. Mokau river mouth
    Nitrogen load (tonnes/year) by 2050 at the following locations:
  4. Piako river mouth
      1. Waihou river mouth
      2. Waikato river mouth
      3. Karapiro Dam
      4. Taupo Gates
      5. Waipa river mouth
      6. Mokau river mouth
      7. Energy use (Total) in sector (GJ, oil equivalents): All sectors by 2050
      8. Energy related CO2 emissions in sector (tonnes): All sectors by 2050
      9. Solid waste in sector (tonnes): All sectors by 2050
      10. Threatened Environments by 2050


Economic indicators

  1. Added value in sector (mln$2004): All sectors (Gross Regional Product – GRP) by 2050
  2. Added value in sector (mln$2004): Forestry and logging by 2050
  3. Employment in sector (FTE): Forestry and logging by 2050
  4. Employment in sector (FTE): Livestock and cropping farming by 2050
  5. Employment in sector (FTE): Dairy cattle farming by 2050


Outputs from each of the scenarios below were recorded in an excel spreadsheet  and comparisons made against the same outputs from the baseline scenario as at 2050. Where significant differences were noted in the indicators then these were explored as to how these compared and how those indicators changed over time at the key time steps of 2006, 2012, 2022, 2032, 2042 and 2050.



Scenario 7c is the final scenario that was used to derive results that were presented to the policy committee of council. Scenario 7c was derived by combining a number of other individual scenarios (see section 2.6 above).


Policy Implications


Associated Models

Waikato Integrated Scenario Explorer (WISE)

The Waikato Integrated Scenario Explorer (WISE) is an Integrated Spatial Decision Support System (ISDSS) designed specifically for New Zealand which focuses on the Waikato region.