Methods - how we monitor
Where and how we collect the data
Footprint calculations are based on region-wide population, economic and energy statistics and models.
This benchmark ecological footprint calculated for the Waikato region was calculated for the 1997-98 year. This update is for the 2003/04 year. This indicator will be updated every five years, with the next update planned for 2009 (to be published 2011).
This indicator is based on data collected between 2002 and 2005 with calculations applying to the 2003-2004 year.
The regional ecological footprint is largely based on region-wide economic data and models based on data supplied by Statistics New Zealand1and includes:
- Population statistics based on sub-national estimates produced by Statistics New Zealand (2004)2, with a population estimate of 381,900 used for the Waikato region.
- Estimates of embodied land, energy and material flows through the economic transactions between the region's economic sectors. These are derived from input/output tables compiled by Statistics New Zealand.
- Estimates of land use data by economic sector based on data gathered from Quotable New Zealand (2004)3, Ministry of Agriculture and Forestry (2004)4, and Agriquality New Zealand (2004) )5 Works Consultancy Services Limited (1996)6 . The latter is the source of the National Traffic database used to estimate the road component of 'built land'.
- Energy related carbon dioxide emissions by economic sector obtained from the Energy Efficiency Conservation Authority (2004)8. The conversion of carbon dioxide emissions into energy land is based on Hollinger et al. (1993)9.
For further details on data sources see .
How the indicator is compiled
The Waikato Regional Ecological Footprint includes three elements - land use required from:
- within the Waikato region (intra-regional)
- other regions (inter-regional)
- other countries (international).
Three databases are required to calculate the Waikato Regional Ecological Footprint:
- 'Generation of Regional Input-Output Tables' (GRIT), which measure the use of resources and the generation of wastes and emissions through the region’s economy, including interactions between industry sectors. These tables use internationally standardised GRIT methodology (a non-survey modelling technique).
- Land inputs (land area used by each economic sector).
- Energy data - carbon dioxide outputs/emissions by sector. This data is converted into ‘area of land used’ by applying a ‘pinus radiata’ (pine forest)carbon uptake rate.
The intra-regional calculation measures the amount of land from within the Waikato region required to meet current levels of ‘final demand’ (that is, final consumption of goods and services produced in the Waikato region). This is then adjusted to account for land appropriated through imports and exports (inter-regional and international trade).
Adding all the sectors gives the regional total land area. Dividing by the regional population generates ‘per person’ ecological footprint figures.
To compare the Waikato region’s ecological footprint (McDonald and Smith, 2006) with:
- the average New Zealand ecological footprint (Hails 2006)
- ecological footprints of other countries (Hails 2006)
- the global ecological footprint (the average world-wide ‘per capita’ footprint, or ‘Earthshare’) (Hails 2006).
the following steps were taken:
- 'Per person' ('per capita') ecological footprint figures for the Waikato region (3.68 - including fishing grounds) calculated by McDonald and Smith (2006) were adjusted to match global estimates generated by Hails (2006).
- Modifications included:
- the use of global average biological productivity yields, such as kilogram of milk per hectare of land (instead of local New Zealand yields)
- the use of equivalence factors (to take into account any variations in biological productivities) for the various land types
- applying a global average carbon dioxide sequestration factor, and including sea space and carbon dioxide absorption by oceans.
This resulted in an adjusted ecological footprint for the Waikato region of 5.8 ha per person.
Guidelines and standards
None relevant to this indicator.
There are a number of limitations in calculating this indicator:
- The focus on ‘productive land’ in the context of the Waikato Regional Ecological Footprint excludes conservation land, and other non-productive land uses. The use of alternative units (for example, energy) may be a better measure from an ecological perspective.
- The assumptions made for deriving energy land.
- The use of local yields (New Zealand, rather than global averages) was used whenever possible. However, for some aspects there was a lack of data.
- Static assumptions where dynamic modelling would be preferable.
- Generally has limited policy relevance, although there is the potential to break ecological footprints down into components that can be used for target setting (for example, transport, energy, consumption).
- GRIT versus survey-based input-output tables - the latter would be more accurate, however they still need a more detailed breakdown of economic sectors (for example, agriculture can be broken down into sheep/beef, dairy, horticulture and other categories).
- Energy land conversion numbers.
The current indicator is the second comprehensive and systematic quantification of the Waikato Region Ecological Footprint. Significant improvements have been incorporated into the analysis including:
- greater resolution of the within economy transactions has been achieved through the use of a 48-industry breakdown of the economy compared with the earlier 23 industry breakdown
- the incorporation of land use data from Agriquality New Zealand's database
- the incorporation of extended reporting on other important resources and emissions such as delivered energy, energy related air emissions and solid waste production.
The Waikato Ecological Footprint could be further improved by:
- Developing productivity indices for each New Zealand region. This would substantially improve the goods-based components of the Ecological Footprint i.e. agricultural land.
- Adding to the number of resources, pollutants and other emissions analysed in the 'extended footprint'.
Quality control procedures
Data analysis and quality assurance procedures set out by McDonald and Patterson (2001) were used in the calculation of the Waikato Regional Ecological Footprint.
- Copyright: Information obtained from Statistics New Zealand may be freely used, reproduced, or quoted unless otherwise specified. In all cases Statistics New Zealand must be acknowledged as the source.
- Statistics New Zealand. 2004: Sub-national population estimates 2001-2026. Wellington. Statistics New Zealand.
- Quotable New Zealand. 1998: Unpublished land area data disaggregated by 99 use codes for all regions in New Zealand. Wellington. Quotable New Zealand.
- Ministry of Agriculture and Forestry. 2004: A National Exotic Forest Description as at 1 April 1998. Wellington. Ministry of Agriculture and Forestry.
- Agriquality New Zealand. 2004. Regional Agricultural Land Use by Farm Type. Wellington. Agriquality New Zealand.
- Works Consultancy Services. 1996: Transit New Zealand National Traffic Database. Contents and Operation of Database. Transit New Zealand Research Report No. 53. Wellington. Transit New Zealand.
- Energy Efficiency Conservation Authority (EECA). 2004: Energy Use Database. Handbook. Wellington. EECA.
- Hollinger, D.Y., Maclaren, J.P., Beets, P.N. and Turland, J. 1993:Carbon Sequestration by New Zealand Plantation Forests. New Zealand Journal of Forestry Science 23:2 194-208.