New Land Cover Database Version in Development

Date: 17 March 2009

NZGO is supporting the Ministry for the Environment (MfE) in developing a third version of the New Zealand Land Cover Database (LCDB). This complements international efforts to represent land cover, such as the European Space Agency's (ESA) global land cover map, made available online late last year.

To find out some of the particular needs required of the new LCDB, MfE held four workshops in Christchurch, Dunedin, Palmerston North and Hamilton during late 2008 to early 2009. The workshops attracted approximately 100 participants in total. A range of suggestions and concerns were discussed and MfE is considering how these can be incorporated or resolved.

A key challenge with land cover maps, and something raised during the workshops, is that classes of land cover are often defined inconsistently. For example, there are many different ways of defining ‘forest'. A key question is whether the number of land cover classes should be rationalised or increased.

MfE hope to have a design specification for the new LCDB by the end of June.

What is land cover?

Land cover maps show different classes or types of land use, such as urban, grassed and forested areas. Information for land cover maps is captured by remote sensing imagery from satellites.

The LCDB maps provide valuable information that can be used to monitor and report on changes to New Zealand's environment. They provide a strong basis for making better resource management decisions, more efficient use of natural resources and improved environmental management.

Updating the LCDB is important to ensure it meets current resource and environmental needs. The existing two versions of the LCDB depict New Zealand's land cover in 1996-97 and 2001-02.

Global land cover

The ESA global land cover map is the highest resolution global satellite map released to date. Nineteen months worth of data, collected between December 2004 and June 2006, is represented in 22 different land cover classes. The data was captured using Envisat's Medium Resolution Imaging Spectrometer (MERIS) at a spatial resolution of 300 metres.

The global land cover map is available through ESA's GlobCover website. Users are required to register before accessing data.  

For more information on the global land cover map, visit the ESA website.

For more information on the LCDB project, please contact Karl Majorhazi from MfE at karl.majorhazi@mfe.govt.nz or phone 04 439 7455.