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LCDB v4.0 Released

posted 29 Jun 2014, 22:06 by David Pairman   [ updated 7 Jul 2014, 21:47 ]

Version 4.0 of the Land Cover Database is now available from our download portal at  

LCDB v4.0 incorporates a new 2012 time-step primarily based on SPOT satellite imagery acquired between November 2011 and February 2013. In addition, this version corrects errors noticed for earlier time periods and refines unsatisfactory line-work representations. Specific mapping activities included:

  • Incorporation of improved wetland mapping from six regional councils
  • Mapping of detected change between 2008/09 and 2012/13 including that associated with harvesting/replanting of production forests
  • Correction of error (in classification or delineation) noticed in the vicinity of edits undertaken above and those notified by users
  • Incorporation of new urban development not detected by the change analysis above but recorded in the LINZ core record system (cadastral) database

Of course, these changes are cumulative from those made in version 3.3 released last October that, in addition to fixing errors we were aware of,  incorporated a review of South Island tussock and low producing grasslands and updated croplands mapping to account for interim work from the LUM maps.

In version 4.0, over 63,000 polygons have either changed class or have been significantly (> 20% of their area changed) re-mapped to improve boundaries. A direct intersection with v3.3 produces over 260,000 polygons of change. The difference between these numbers  indicates that a lot of minor boundary improvements have been made.  


Unlike the mapping done for LCDB v3.0, this time we have not formally passed draft maps back to Regional Councils and other interest groups for checking. Our experience with LCDB v3.0 was that the feedback and number of errors identified was extremely variable between regions. It was obviously difficult to get the appropriate staff in those organisations really focused on this task within the tight timeframes. On our side, creating gaps for this checking made it difficult to efficiently use the mapping staff that we had available.  For v4.0 we felt it was better to press on, using the time to make a better job of the mapping and to incorporate much more formal internal checking of results in the workflow, and then to encourage external feedback on a more relaxed timeframe. 

Error Feedback

Instead of passing draft maps to key interest groups, an online data quality feedback (DQF) facility has been incorporated into the download site. This enables users to report specific polygons as requiring attention by submitting a tracked report, or ticket, giving details of the problem and attaching associated evidence such as pictures, screen shots etc. We would really encourage all users and particularly key interest groups to make use of this facility. The intention is that we will make a further release (v4.x) of the LCDB within the next year to both incorporate any errors identified and to apply changes identified by new methodologies that were not ready when the version 4.0 workflows were developed.

Usage Feedback

As any user can download the LCDB we will not always be aware of applications making use of it. We would really appreciate any feedback you are willing to give us on this, both to help us report to the Ministry of Business Innovation and Employment (our funders), but also to help chart the future for the LCDB. Even a couple of lines in an email alerting us to an application would be useful – we can always follow up if we need more detail. Alternatively, feel free to call me or Peter Newsome on 03 321 9763 or 06 353 4975 respectively, to let us know what you do with LCDB.

Update 1-July-2014

Three sets of summary pivot tables have been generated from LCDB v4.0  to show change between the time steps, i.e., 1996-2001, 2001-2008, and 2008-2012. These tables contain analysis for both the national coverage and by region. They are best accessed via the links on the LCDB v4.0 download page

There is also a change layer to track both non-temporal and temporal change between LCDB v3.3 and LCDB v4.0 available at  As all four time steps are present in v4.0, this change layer, and the earlier change layers for v3.3 vs v3.0 and v3.0 vs LCDB-2, are only relevant to users who need to reconcile analysis done on an earlier version with results from a newer version. You should only need the most recent LCDB version for new studies of real temporal change.