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    Distributional data for eight taxonomic groups (asteroids, bryozoans, benthic foraminiferans, octocorals, polychaetes, matrix-forming scleractinian corals, sponges, and benthic fish) have been used to train an environmental classification for those parts of New Zealand's 200 n. mile Exclusive Economic Zone (EEZ) with depths of 3000 m or less. A variety of environmental variables were used as input to this process, including estimates of depth, temperature, salinity, sea surface temperature gradient, surface water productivity, suspended sediments, tidal currents, and seafloor sediments and slope. These variables were transformed using results averaged across eight Generalised Dissimilarity Modelling analyses that indicate relationships between species turnover and environment for each species group. The matrix of transformed variables was then classified using k-meDOIds clustering to identify an initial set of 300 groups of cells based on their environmental similarities, with relationships between these groups then described using agglomerative hierarchical clustering. Groups at a fifteen group level of classification appropriate for use at a whole-of-EEZ scale are described; the classification can also be used at other levels of detail, for example when higher levels of classification detail are required to discriminate variation within study areas of more limited extent. Although not formally tested in this analysis, we expect the analytical process used here to increase the biological discrimination of the environmental classification. That is, the resulting environmental groups are more likely to have similar biological characteristics than when the input environmental variables are selected, weighted, and perhaps transformed using qualitative methods. As a consequence, they are more likely to be reliable when used as "habitat classes" for the management of biological values than groups defined using alternative approaches.

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    The New Zealand Land Resource Inventory (NZLRI) is a national database of physical land resource information. It comprises two sets of data compiled using stereo aerial photography, published and unpublished reference material, and extensive field work: 1. An inventory of five physical factors (rock type, soil, slope, present type and severity of erosion, and vegetation). A 'homogeneous unit area' approach is used to record the five physical factors simultaneously to a level of detail appropriate for presentation at a scale of 1:50,000. 2. A Land Use Capability (LUC) rating of the ability of each polygon to sustain agricultural production, based on an assessment of the inventory factors above, climate, the effects of past land use, and the potential for erosion. The NZLRI covers the country in 11 regions, each with a separate LUC classification. The first edition NZLRI provides national coverage from mapping between 1973 and 1979 at a scale of 1:63,360. A limited revision regional upgrade of the north Waikato area was completed at a scale of 1:63,360 in 1983. Second edition NZLRI regional upgrades at a scale of 1:50,000 have been completed for Northland, Wellington, Marlborough and Gisborne-East Cape. Third edition NZLRI layers contained a restructured polygon attribute table to allow the core NZLRI to complement the newly created fundamental soil layers with minimal duplicationThe first edition NZLRI provides national coverage from mapping between 1973 and 1979 at a scale of 1:63,360. These data were digitised for GIS retrieval in 1981 (Version 1.1) A limited revision regional upgrade of the north Waikato area was completed at a scale of 1:63,360 in 1983. (Version 1.2) A polygon boundary and attribute validity edit over the whole database was completed in 1992. Attributes to accommodate second edition classifications were added in preparation for incorporating 1:50,000 remapping (Version 2.1) Second edition NZLRI regional upgrades at a scale of 1:50,000 were completed for Northland in 1988 and Wellington in 1991and incorporated into the datbase (not present in this layer) in 1992. (Version 2.2) A second edition NZLRI regional upgrade at a scale of 1:50,000 was completed for eastern Marlborough in 1995 (Version 2.3) A second edition NZLRI regional upgrade at a scale of 1:50,000 was completed for Gisborne-East Cape (not present in this layer) in 1999 (Version 2.4) In 2000, at the time the first generation fundamental soil layers were created, the (mainly soil elements of the) polygon attribute table was restructured so that the two datasets would be complementary with minimal diplication (Version 3.1) Incidental error correction has occurred as necessaryThe multi-factor, homogenous unit area mapping, method tends to result in themes being delineated at lower resolution than a single factor map of equivalent scale. Erosion and Vegetation were often recorded within units defined primarily on the basis of Rock, Soil, and SlopeWhile mapping scale remained constant (at 1:63,360 and later 1:50,000), polygon resolution increased in detail as the survey progressed, and was variably constrained by the quality of source information available to the mapperSurvey date, and therefore currency of data, varies from 1973 to 1998. Rock, Soil, and Slope are less affected by survey date than vegetation and erosionhttps://lris.scinfo.org.nz/layer/135/ & https://lris.scinfo.org.nz/layer/48134-nzlri-north-island-edition-2-all-attributes/