Land Environments of New Zealand (LENZ)

The data set provides an environmental classification of New Zealand that is designed to provide a framework for addressing a range of conservation and resource management issues. LENZ works at a range of scales and provides information about climate, soils and landforms. The Ministry for the Environment uses LENZ as a tool to underpin indicator-based monitoring of the state of New Zealand's environment. Purpose: To provide a framework for addressing a range of conservation and resource management issues.

numerical data layers describing various aspects of New Zealand's climate, landforms and soils. LENZ is presented at four standard levels of classification detail, containing 20, 100, 200, and 500 environments nationally.

New Zealand wide

Waikato region –

climate – 1950 -1980, soil –last 40 years.

All seven climate layers were derived either directly or indirectly from mathematical surfaces that use information about the climate, location and elevation of a number of meteorological stations. Each surface is calculated using a process in which data values for each climate station are omitted in turn and its climate is predicted from the surrounding stations. This process is repeated until no further improvement can be made to the fit of the surface to the raw data. The slope data layer was created from a 25-metre digital elevation model (DEM) fitted to 20 m digital contour data derived from New Zealand's NZMS 260 map series using in-house software developed at Landcare Research. All contours were originally derived photogrammetrically from stereo photographs for final map reproduction at a scale of 1:50 000. Additional intermediate contours and spot heights were used in generating the DEM where available, while coastlines and shoreline were used to constrain the DEM surface around water bodies. The linear interpolation method used to create the DEM treads contours through the cells before interpolation so that any cell intersected by a contour will be given the elevation value of that contour, leading to a high percentage of cells with elevations that are multiples of 20 or 10 in steep areas. The soil layers are based on the New Zealand Land Resource Inventory and the National Soils database and errors addressed where possible. See Leathwick et al. (2002) for more details. Frequency of collection: Various

The degree to which LENZ can predict individual species distributions requires clarification. The geographical scale limitations of the underlying data layers affect the ability of LENZ to predict biological components of ecosystems, particularly at finer scales. Change in climate. Gaps in collection: Not reported Data quality: Not reported Attribute accuracy: see Leathwick et al. (2002) for data reliability, particularly the soil layers. Completeness: Subjective decision about the choice of environmental variables to use.

colour atlas, technical guide, electronic Digital Format: GIS (ArcView 3.2) - raster data

Freely available Sensitivity/Confidentiality: See Landcare Research, Hamilton ([email protected]) for access to underlying layers.

LENZ uses environmental space not geographic space, therefore classification units can have wide geographical dispersion.