Land cover

  • Image, Land cover.

    Land cover describes the extent of vegetation, water bodies, built environments, and bare natural surfaces (eg gravel and rock) across New Zealand. Measuring the composition of and changes in land cover can help us understand the pressures that different land uses are placing on the biodiversity and functioning of ecosystems.

    We classified Land cover as a national indicator.

    Key findings

    Trend not assessed

    Exotic forest had the largest increase in area (up 215,655 ha or 11.2 percent) from 1996 to 2012. Urban land also increased over this period (up 21,050 ha or 10.2 percent), with the largest increases being in Auckland (4,211 ha), Waikato (3,900 ha), and Canterbury (3,829 ha) regions.

    • The largest decrease in area of land cover was in exotic grasslands, down 1.7 percent or 183,571 ha.
    • Other decreases in land cover were tussock grasslands (down 1.3 percent or 30,929 ha), exotic scrub/shrubland (down 9.3 percent or 25, 978 ha), indigenous scrub/shrubland (down 1.3 percent or 24,187 ha), and indigenous forests (down 0.2 percent or 16,108 ha).
    • Growth in exotic forests was led by Gisborne (up 24.9 percent or 35,573 ha), Manawatu-Wanganui (up 24.5 percent or 31,449 ha), and Otago (up 24.9 percent or 31,031 ha).
    • The largest decreases in exotic grassland cover were in Gisborne (down 9.9 percent or 39,069 ha), Marlborough (down 9.6 percent or 32,795 ha), Manawatu-Wanganui (down 2.1 percent or 26,728 ha) and Hawke’s Bay (down 3.6 percent or 25,854 ha).
    • Regions with the largest decreases in indigenous forest cover were the West Coast (down 0.4 percent or 5,354 ha), Taranaki (down 1.0 percent or 2,414 ha), and Marlborough (down 0.8 percent or 2,190 ha).

    At 2012:

    • Exotic grassland covered 39.6 percent (10.6 million ha) of New Zealand’s total land area.
    • Indigenous forests covered 25.9 percent (7.0 million ha) of New Zealand’s land area.
    • Urban land area covered 0.8 percent (0.23 million ha) of New Zealand’s total land area.
    Figure 1
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    Figure 1A
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    Figure 2

    Figure 3

    Note: The total area of New Zealand has been calculated to 26,842,400.95 hectares

    Definition and methodology

    The New Zealand Land Cover Database (LCDB) is a national classification of land cover, mapped using satellite imagery. The LCDB maps areas of vegetation that are at least one hectare in size. We used version 4.1, released in July 2015, which covers mainland New Zealand, the nearshore islands, and the Chatham Islands; although we exclude the Chatham Islands in our analysis.

    LCDB 4.1 includes four maps, correlating to the four summer survey periods – 1996/97, 2001/02, 2008/09, and 2012/13. The land cover classification was developed over the first three surveys. Classification changes can be tracked to allow comparison between different maps and different versions of the data.

    The classification is based on 33 lower-order classes, which we aggregated into 12 medium-order classes for this indicator. These medium-order classes provide sufficient detail to identify major land cover changes, and were selected to align with reporting on the Land, Air, Water Aotearoa (LAWA) website.

    Note that in 2015, we reported land cover using a slightly different set of medium-order classes. We also used LCDB 4.0 (2012), which is different to 4.1. Since 2012, there has been no new major version of LCDB, that is, no more recent data are available, but version 4.1 has incorporated some improvements, including removing confusion around indigenous/exotic and forest/scrub classes, and improving some polygons. See Land Resource Information Systems for further detail.

    To update this indicator, we provided more granular analysis and some regional breakdowns of land cover change.

    Data quality

    We classified Land cover as a national indicator.

    Relevance

    relevance-direct  This national indicator is a direct measure of ‘Land cover, ecosystems, and habitats’ topic.

    Accuracy

    accuracy-high The accuracy of the data source is of high quality.

    See Data quality information for more detail.

    Archived versions

    See Land cover (archived April 2018)

    Published 19 April 2018

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