11.1 General information
For 2008, net removals from land subject to afforestation, reforestation and deforestation were –14,416.8 Gg CO2-e (Table 11.1.1). This value includes removals from the growth of post-1989 forest, and emissions from the conversion of land to post-1989 forest, harvesting of forests planted on non-forest land after 31 December 1989, deforestation of all forest, and from disturbance associated with land-use conversion to cropland, liming and biomass burning. These net emissions and removals are reported by the North and South Islands for the five carbon pools (Figure 11.1.1). Afforestation, reforestation and deforestation are key categories (Table 1.5.4).
For reporting under Article 3.3 of the Kyoto Protocol, New Zealand has chosen to categorise its forests into three subcategories: natural forest; pre-1990 planted forest and post-1989 forest. These three subcategories are also used for reporting on the land use, land-use change and forestry (LULUCF) sector under the Climate Change Convention (chapter 7). All forest land that existed at 31 December 1989 is categorised as either natural forest or pre-1990 planted forest. For these forests, only emissions from deforestation activities are reported in this chapter. For the post-1989 forests, emissions and removals from carbon losses and gains due to afforestation, reforestation and deforestation are reported for the first year of the commitment period.
|Source||Gross area (ha) 1990–2008||Net area (ha) |
|Emissions in 2008 (Gg CO2-e)|
|Forest land not harvested since the beginning of the commitment period||–||568,274||–17,395.1|
|Forest land harvested since the beginning of the commitment period||–||500||67.8|
Notes: Afforestation/reforestation refers to new forest established since 1 January 1990. The gross afforestation/reforestation area includes 11,749 hectares of land in transition to post-1989 forest that has subsequently been deforested. The net afforestation/reforestation area includes 1,000 hectares of new forest plantings in 2008. The 2008 areas are as at 31 December 2008. Columns may not total due to rounding.
Between 1990 and 2008, 580,524 hectares of new forest (post-1989 forest) were established as a result of afforestation and reforestation activities – an average of 31,000 hectares per year (refer to Figure 188.8.131.52). Deforestation in 2008 of all subcategories of forest land (post-1989, pre-1990 planted and natural forest) is estimated at 4,818 hectares (equivalent to emissions of 2,910.6 Gg CO2-e).
A detailed analysis of 2008 emissions and removals shows:
- the total net CO2 removals based on carbon stock change were –14,417.3 Gg CO2
- nitrous oxide emissions from disturbance associated with land-use conversion to cropland were 0.001 Gg N2O (0.3 Gg CO2-e)
- carbon dioxide emissions from lime application of deforested land are estimated at 0.7 Gg CO2
- emissions from the burning of biomass on afforestation/reforestation land were 0.016 Gg CH4 (0.3 Gg CO2-e) and 0.001 Gg N2O (0.02 Gg CO2-e).
There is no reduction in the carbon stock made for areas burnt prior to forest harvesting or deforestation. Consequently, CO2 emissions associated with biomass burning are captured by, and reported under, the general carbon stock change calculation for forests.
Figure 11.1.1 New Zealand’s net CO2 emissions and removals associated with afforestation, reforestation and deforestation activities in 2008
|Region||Net emissions/removals associated with afforestation, reforestation and deforestation activities in 2008 by carbon pool (Gg CO2)|
|Above-ground biomass||Below-ground biomass||Dead wood||Litter||Soil organic matter|
Note: Emissions and removals shown are the result of changes in carbon stock only and do not include
New Zealand is not reporting on:
- liming of afforested and reforested land as this activity does not occur
- non-carbon dioxide emissions from controlled burning on deforested land as there is insufficient data to quantify the emissions from this activity. The notation NE (‘not estimated’) is reported in the common reporting format tables for controlled burning associated with deforestation.
- emissions associated with fertiliser use on deforested land, as these are reported in the agriculture sector.
Afforestation and reforestation
Between 1990 and 2008, it is estimated that 580,524 hectares of new forest (post-1989 forest) was established as a result of afforestation and reforestation activities. The net area of post-1989 forest as at 31 December 2008 was 568,775 hectares. The net area is the total area of new forest minus deforestation since 1 January 1990.
Deforestation of all forest types in 2008 is estimated at 4,818 hectares (equivalent to emissions of 2,909.8 Gg CO2 from carbon stock change). This is a decrease from the 18,151 hectares (13,115.6 Gg CO2) of deforestation in 2007. New Zealand’s post-1989 forests are described in further detail in section 7.2.2.
The new planting rate (land reforested or afforested) between 1990 and 2008 was, on average, 31,000 hectares per year (refer to Figure 184.108.40.206). While new planting rates were high from 1992 to 1998 (averaging 59,000 hectares per year), the rate of new planting has declined rapidly since 1998 and is now at very low levels. In the 2008 calendar year, it was estimated that only 1,000 hectares of new forest was established. The annual area of new planting is expected to increase with the implementation of the New Zealand Emissions Trading Scheme, Permanent Forest Sinks Initiative and Afforestation Grant Scheme, that have both been introduced by the New Zealand Government to encourage new planting (Ministry of Agriculture and Forestry, 2009b).
In 2008, 4,818 hectares of forest land are estimated to have been deforested, which is equivalent to emissions of 2,909.8 Gg CO2 from the estimated change in carbon stock. Table 11.1.2 shows the areas of forest land subject to deforestation in 2008, and Figure 11.1.2 shows the net emissions associated with this deforestation.
|Forest land subcategory||Area of deforestation in 2008 (ha)||Emissions in 2008 from resulting carbon stock change (Gg CO2)|
|Pre-1990 planted forest||2,114||1,552.6|
Note: 2008 areas as at 31 December 2008.
The New Zealand Government has recently introduced legislation and government initiatives to either encourage forest establishment or discourage the deforestation of planted forests. These include:
- Climate Change Response Act 2002 (updated 8 December 2009)
- Permanent Forest Sink Initiative (Ministry of Agriculture and Forestry, 2008b)
- Afforestation Grant Scheme (Ministry of Agriculture and Forestry, 2009b).
The New Zealand Emissions Trading Scheme means that owners of pre-1990 planted forest are only able to deforest 2 hectares in any five-year period starting from 1 January 2008 without having to surrender emissions units (Ministry of Agriculture and Forestry, 2009b). Above this level of deforestation they have to surrender units equal to reported emissions, with some exemptions for smaller forest owners.
The area of deforestation of natural forests estimated for 2008 is based on previous trends and is likely to be an overestimate. This is because land-use change during the 2008 calendar year was estimated by linear interpolation from the average land-use change mapped between 1 January 1990 and 1 January 2008. As there was no quantitative information on the annual rate of natural forest deforestation between 1990 and 2007, the same annual rate of change was assumed for the entire period (1,818 hectares per year), and extrapolated out to the end of 2008.
However, a number of factors suggest that the rate of natural forest deforestation is unlikely to have been constant over the 19-year period, and instead mostly occurred prior to 2002. The area available for harvesting (and potentially deforestation) was higher before amendments were made in 1993 to the Forests Act 1949. There have also been government controls on deforestation of natural forests since the 1970s, with only a small proportion of privately owned natural forest exempt from these controls (0.7 per cent of the total area of natural forest is exempt). Further restrictions to the logging of natural forests were introduced in 2002, resulting in the cessation of logging of publicly owned forests on the West Coast of New Zealand in 2002. These developments are all likely to have reduced natural forest deforestation since their introduction.
The extrapolated estimate of natural forest deforestation will be updated in future submissions as new information becomes available, and will be replaced with an actual, mapped value in the 2013 submission at the latest, following production of the 2012 land-use map.
Figure 11.1.2 New Zealand’s net emissions from deforestation from 1990 to 2008
|Year||Net emissions from deforestation by forest land subcategory (Gg CO2)|
|Natural forest||Post-1989 forest||Pre-1990 planted forest|
While conversion of land from one land use to another is not uncommon in New Zealand, deforestation on the scale seen since 2004 is a new phenomenon. Most of the area of planted forest deforested from the mid-2000s has been converted to grassland. This conversion is most likely primarily due to the relative profitability of some forms of pastoral farming (particularly dairy farming) compared with forestry.
Deforestation in New Zealand is more fully described in sections 7.2.1 and 11.4.2.
11.1.1 Definitions of forest and any other criteria
New Zealand has used the same forest land definition as used for the LULUCF sector under the Climate Change Convention reporting (chapter 7) and as defined in New Zealand’s Initial Report under the Kyoto Protocol (Ministry for the Environment, 2006). Table 220.127.116.11 provides the defining parameters for forest land.
|Forest parameter||Kyoto Protocol range||New Zealand selected value|
|Minimum land area (ha)||0.05–1||1|
|Minimum crown cover (%)||10–30||30|
|Minimum height (m)||2–5||5|
Note: The range values represent the minimum forest definition values as defined under the Kyoto Protocol, decision 16/CMP.1.
The minimum width of 30 metres removes linear shelterbelts from the forest category. The width and height of linear shelterbelts can vary as they are trimmed and topped from time to time. Further, they form part of non-forest land uses, namely cropland and grassland as shelter to crops and/or animals.
The definition used for reporting to the Food and Agriculture Organization is different from that used for Climate Change Convention and Kyoto Protocol reporting. New Zealand has not adopted a formal definition of forest type for reporting to the Food and Agriculture Organization. New Zealand has instead used the international definition proposed in the United Nations Economic Commission for Europe/Food and Agriculture Organization Temperate and Boreal Forest Resources Assessment 2000: “…an association of trees and other vegetation typical for a particular site or area and commonly described by the predominant species, for example, spruce/fir/beech” (UN-ECE/FAO, 2000). For reporting to the Food and Agriculture Organization, New Zealand subdivided forests into two estates based on their biological characteristics, the management regimes applied to the forests and their respective roles and national objectives (Ministry of Agriculture and Forestry, 2002). The two estates are indigenous and planted production forest. The former estate largely equates to natural forest as reported in this submission, and the latter largely equates to pre-1990 planted forest and post-1989 forests. There is an overlap where post-1989 forest has been established with native species or is the result of revegetation.
11.1.2 Elected activities under Article 3.4
As stated in New Zealand’s Initial Report under the Kyoto Protocol (Ministry for the Environment, 2006), New Zealand has not elected any of the activities under Article 3.4 of the Kyoto Protocol.
11.1.3 Implementation and application of activities under Article 3.3
The area of afforestation/reforestation reported under the Kyoto Protocol is equal to the net area of post-1989 forest reported for land-use change to forest land reported in the LULUCF sector. Between 1990 and 2008, 580,524 hectares were reforested and 1,000 hectares of this occurred in 2008. Of the total area reforested between 1990 and 2008, an estimated 11,749 hectares were deforested between 1990 and 2008. Once an area has been tagged as deforested it remains in this category for the first commitment period. Therefore all subsequent stock changes and emissions and removals on this land are reported against units of land deforested.
Tracking of these deforestation areas in the Land Use and Carbon Analysis System (LUCAS) Calculation and Reporting Application (Annex 3.2) ensures that land areas, once deforested, cannot be reported as afforestation or reforestation land and that the emissions and removals are reported under the land use the area is converted to.
New Zealand’s intention is to account for all activities under Article 3.3 of the Kyoto Protocol at the end of the commitment period (Ministry for the Environment, 2006).
11.2 Land-related information
11.2.1 Spatial assessment unit
New Zealand is mapping land use to 1 hectare.
11.2.2 Methodology for land transition matrix
Mapping of land use as at 1990 and 2008 focused on the classes containing woody biomass (natural forest, pre-1990 planted forest, post-1989 forest and grassland with woody biomass). Satellite imagery was used to map woody classes as at 1 January 1990 and 1 January 2008. The mapping of land-use change prior to 2008 was based on these maps, high-resolution photography and field visits.
The 1990 land-use map was derived from 30 metre spatial resolution Landsat 4 and Landsat 5 satellite imagery taken in, or close to, 1990. The 2008 land-use map (land use as at 1 January 2008) was derived from 10 metre spatial resolution SPOT 5 satellite imagery and was processed into standardised reflectance images, using the same approach as for the 1990 imagery. Refer to section 7.1.2 for further explanation of the land-use mapping methodology.
The remaining land-use categories were mapped based on existing information from two land cover databases, LCDB1 (1996) and LCDB2 (2001) (Thompson et al, 2004), the New Zealand Land Resource Inventory (NZLRI) (Eyles, 1977) and hydrological data from Land Information New Zealand have been used (Shepherd and Newsome, 2009a, b).
Decision process for mapping post-1989 forests
The use of remote sensing has some limitations, in particular, the ability to map young planted forest of less than three years of age. Where trees are planted within three years of the image acquisition date they (and their surrounding vegetation) are unlikely to show a distinguishable spectral signature in satellite imagery. This occurs particularly with coarse resolution (30 metres) 1990 Landsat imagery. This situation is compounded by the lack of ancillary data to support land-use classification decisions.
To aid the decision-making process, the LUCAS mapping also used nationwide and cloud-free 1996 SPOT and 2001 Landsat 7 satellite imagery to determine the age of forest that might have been planted between 1990 and 1993. This process is designed to reduce errors of omission and ensures all forests are mapped. Figure 18.104.22.168 illustrates how mapping operators determined the status of an area of planted forest established between 1990 and 1993, with a situation where an area was classified as post-1989 forest by assessing the 1990, 1996 and 2001 satellite imagery. The 1990 image shows no obvious spectral signature of any forest vegetation within the blue box. However, the 1996 and 2001 images show strong forestry spectral signatures. If the 1990 imagery had shown some spectral signature that corresponds to the forest boundary in 1996 the mapping operators would have classified the area as pre-1990 planted forest. By applying this method, the later date imagery is used to confirm subtle variations in spectral signature in the 1990 imagery that correspond to young planted forest.
Where possible, information obtained directly from forest owners is also used to improve the accuracy of the pre-1990/post-1989 forest classification.
Figure 22.214.171.124 Identification of post-1989 forest in New Zealand (Dougherty et al, 2009)
Figure 126.96.36.199 illustrates the process for identifying post-1989 forest in New Zealand. In the photographs shown, satellite imagery can be seen to be providing key information for making a 1990 land-use decision. The area inside the blue box in the top-left image is classified as ‘Grassland – low producing’ in the 1990 land-use mapping data. The area inside the box can then be seen using the 1996 SPOT imagery, 2000 Landsat imagery and 2008 SPOT imagery as forest that was planted after 1989. From the image sequence above, it can be determined that the area inside the box was correctly classified as Post-1989 forest in the 2008 land-use mapping data.
Where information on the timing of planting and harvesting was not available, ancillary data from the National Exotic Forest Description was used (Ministry of Agriculture and Forestry, 2009a). This process is described in section 7.1.2.
To estimate land-use change in 2008, data from the National Exotic Forest Description (Ministry of Agriculture and Forestry, 2008) and the 2008 Deforestation Intentions Survey (Manley, 2009) and unpublished work by Scion (referenced in Wakelin, 2008) were used for the forest land uses. For the non-forest land uses, change during 2008 was estimated based on the average annual change between 1 January 1990 and 1 January 2008. This is further explained in section 7.1.2.
Land-use change during the first commitment period will be confirmed following mapping at the end of 2012.
11.2.3 Identifying geographical locations
New Zealand is using Reporting Method 1 for afforestation, reforestation and deforestation.
The geographic units New Zealand has chosen to report by are the North Island, including Great Barrier and Little Barrier Islands, and the South Island, including Stewart Island and the Chatham Islands.
11.3 Activity-specific information
11.3.1 Carbon stock change and methods
Description of the methodologies and the underlying
The methodologies and assumptions used for reporting under the Kyoto Protocol Article 3.3 activities are the same as those used for the Climate Change Convention reporting and are described more fully in chapter 7.
Emissions and removals from afforestation and reforestation are determined at the national scale. Carbon analyses based on a plot network is performed to estimate the average amount of carbon per hectare per pool.
Currently, emissions from deforestation are estimated based on average carbon yield tables for each subcategory of forest (natural forest, pre-1990 planted forest and post-1989 forest). A future improvement planned is to use specific carbon stock estimates for emissions from deforestation based on the locality of the deforested area. This will be carried out for individual deforestation polygons where the tree age (from time-sequential, remotely sensed imagery) and land productivity (from a productivity spatial layer) have been determined. The carbon yield tables for all three subcategories of forest will also be updated following measurement of these forests.
Following deforestation, carbon for the new land use then accumulates at rates as given in Table 188.8.131.52.
Justification when omitting any carbon pool or GHG emissions/ removals from activities under Activity 3.3 and elected activities under Article 3.4
New Zealand has accounted for all carbon pools. The carbon in organic soils, however, has been calculated as for mineral soils.
New Zealand uses a Tier 2 method to estimate soil carbon stock, with the use of New Zealand-specific land-use and soil pedon data (Scott et al, 2002). The peer-reviewed Soil Carbon Monitoring System (Soil CMS) does not estimate carbon stock or carbon changes for organic soils, as it calculates concentration within a fixed depth rather than total organic carbon mass (Tate et al, 2005).
Approximately 0.9 per cent of New Zealand’s land area has organic soils, and between 1 January 1990 and 1 January 2008, 2,560 hectares of land with organic soils underwent land-use change. This represents 0.3 per cent of the total area of land-use change. New Zealand has reported organic soils as mineral soils in the reporting of soil carbon, and has used the notation key IE (‘included elsewhere’) for organic soils in the common reporting format tables. See section 7.1.2 for further detail.
Factoring out information
Indirect and natural greenhouse gas emissions and removals have not been factored out, and are therefore included in New Zealand’s emission and removals estimates.
This is New Zealand’s first inventory report to be submitted within the first commitment period of the Kyoto Protocol, and consequently there are no recalculations to afforestation, reforestation and deforestation estimates. However, estimates reported for the LULUCF sector under the Climate Change Convention have been recalculated since the previous submission to incorporate improved New Zealand-specific methods, activity data and emission factors, as detailed under section 7.1.2.
The uncertainty in emissions and removals from afforestation and reforestation units are 15.1 per cent, based on the uncertainty in emissions and removals from post-1989 forest (refer to section 7.2.3 and Table 184.108.40.206 for further details). The uncertainty in emissions from deforestation units is determined by the type of forest land deforested. This may be natural forest, pre-1990 forest or post-1989 forest (Table 220.127.116.11). Further detail on the uncertainty in emissions and removals for natural forest and pre-1990 forest is provided in chapter 7, section 7.2.
|Uncertainty with a 95% confidence interval (%)|
|Source of emissions/ removals||Afforestation/ |
|Land-use subcategory||Post-1989 forest||Natural forest||Pre-1990 forest||Post-1989 forest|
|Activity data uncertainty||±6.5||±5.7||±9.9||±6.5|
|Emission factor uncertainty||±10.1||±3.7||±16.9||±10.1|
|Combined uncertainty||± 12.0||± 6.8||± 19.5||± 12.0|
Note: All land that has been afforested/reforested since 1 January 2008 is, by definition, post-1989 forest. Land deforested since 1 January 2008 may be natural forest, pre-1990 forest or post-1989 forest.
Other methodological issues
Quality-control and quality-assurance procedures have been adopted for all data collection and data analyses to be consistent with IPCC (2003) and New Zealand’s inventory quality-control and quality-assurance plan. Data quality and data assurance plans were established for each type of data used to determine carbon stock and stock changes, as well as the areal extent and spatial location of land-use changes. All data was subject to an independent and documented quality-assurance process. Data validation rules and reports were established to ensure that all data are fit-for-purpose and are of consistent and known quality, and that data quality continues to be improved over time. The data used to derive the country-specific yield tables and average carbon values have also undergone quality assurance as described in section 7.2.4.
Year of the onset of an activity
For the purpose of accounting as required in paragraph 18 of the annex to CMP.1 (land use, land-use change and forestry) attached to decision 11/CP.7, an indication of the year of the onset of an activity is required for activities starting after the beginning of the first commitment period. During 2008, 1,000 hectares of post-1989 forest were established and 4,818 hectares of forest (natural forest, pre-1990 planted forest and post-1989 forest) were deforested.
11.4 Article 3.3
11.4.1 Demonstration that activities apply
All land in New Zealand is under some form of management and management plan. Land is managed for a variety of reasons, including agriculture and/or forestry production, conservation, biodiversity, fire risk management (eg, fire breaks), scenic and cultural values. Most land-use changes occur in agriculture and forestry landscapes. All land-use change, including deforestation, is therefore a result of human decisions to either change the vegetation cover and/or change the way land is managed.
New Zealand has used satellite imagery collected around 1990 and 2008 to detect changes in land use between these two periods. To estimate land-use change in 2008, ancillary data has been used.
Data from the Ministry of Agriculture and Forestry’s new planting survey (the National Exotic Forest Description (Ministry of Agriculture and Forestry, 2009a)) was used to estimate afforestation and reforestation during 2008. To estimate deforestation during 2008, data from forest owners and from the 2008 Deforestation Intentions Survey has been used (Manley, 2009).
Following the mapping of land use at the end of 2012, New Zealand will recalculate the area of land-use change due to afforestation, reforestation and deforestation during the first commitment period.
11.4.2 Distinction between harvesting and deforestation
New Zealand has used the IPCC (2003) definition of deforestation: “Deforestation is the direct human-induced conversion of forested land to non-forested land”. Deforestation is different from harvesting, in that harvesting is part of usual forest management practice and involves the removal of biomass from a site followed by reforestation (replanting or revegetation, ie, no change in land use).
In New Zealand, temporarily unstocked areas (eg, harvested areas and areas subject to disturbances) remain as forest land unless there is a confirmed change in land use or after four years no reforestation (replanting or revegetation) has occurred. The four-year time period was selected because, in New Zealand, the tree grower and land owner are often different people. Forest land can be temporarily unstocked for a number of years while land owners decide what to do with land after harvesting.
Prior to the four-year time period, there are a number of activities that will be carried out to confirm if land-use change has occurred, including the analysis of satellite and aerial photography and airborne scanning LiDAR imagery. These activities are detailed in section 7.1.2. – Mapping of deforestation and harvesting.
Under New Zealand’s Emissions Trading Scheme, owners of pre-1990 planted forest and owners of post-1989 forest who are participants in the scheme are required to notify the government of any deforestation activity (Ministry of Agriculture and Forestry, 2009). There is a data sharing agreement that the Ministry of Agriculture and Forestry, the agency that administers the forestry aspects of New Zealand’s Emissions Trading Scheme, will provide the Ministry for the Environment with regular updates of the area of confirmed deforestation.
To confirm that an area has not been reforested, an inspection of those areas mapped as harvested, based on satellite imagery, will occur two years after the harvesting was mapped. There are a number of approaches to this inspection including: aerial photography, airborne scanning LiDAR and digital aerial photography, and searching for information held either by regional councils, Ministry of Agriculture and Forestry district offices, or forestry consultants. This process is shown in Figure 18.104.22.168.
Figure 22.214.171.124 Verification of deforestation in New Zealand
Figure 126.96.36.199 illustrates the process for verifying deforestation in New Zealand, as described in the text in section 11.4.2 of the Inventory report.
When forest land has been mapped as harvested but has remained unstocked for two years, a number of activities will be carried out to confirm if land-use change has occurred, including looking at alternative sources of information. These include examining existing aerial photography, airborne scanning LiDAR and satellite imagery (MODIS), and searching other sources information held either by regional councils, the Ministry of Agriculture and Forestry district offices, forestry consultants, or in the AgriBase farming database. Where the current land use can be confirmed, the areas are marked as ‘forest’ or ‘deforested’, as applicable. Where the current land use is ambiguous or cannot be confirmed, the land areas will be overflown to verify whether deforestation has occurred. Those areas will then likewise be marked as either as ‘forest’ or ‘deforested’, as is the case.
Following mapping at the end of 2012, the area of deforestation will be confirmed. It may take up to four years for deforestation to be confirmed where areas are harvested within four years of the end of the first commitment period. Where land-use change cannot be confirmed, New Zealand will use a combination of the ratio of area harvested to area deforested over the first part of the commitment period, and high-resolution SPOT-5 (or similar high-resolution optical imagery) acquired at the end of the commitment period to determine the area of deforestation and the likely localities.
Once a land-use change is mapped and confirmed, the deforestation emissions will be reported in the year of forest clearance. This is based on the assumption that, at the time of forest clearance, the intention was to deforest the land and associated emissions occurred in that year.
11.4.3 Unclassified deforestation
Harvested areas are tagged within the geospatial database and will be monitored over time using the method described above and allocated to a land-use change category if they are not replanted or reverting to forest within four years.
11.5 Article 3.4
New Zealand has not elected any activities under Article 3.4 of the Kyoto Protocol (Ministry for the Environment, 2006).
11.6 Other information
11.6.1 Key category analysis for Article 3.3 activities
Afforestation and reforestation, and deforestation of pre-1990 forests are key categories for 2008 (level and trend analysis).
11.7 Information relating to Article 6
New Zealand is not involved in any activities under Article 6 of the Kyoto Protocol.