Data - Page 5

The New Zealand Fundamental Soil Layer originates from a relational join of features from two databases: the New Zealand Land Resource Inventory (NZLRI), and the National Soils Database (NSD). The NZLRI is a national polygon database of physical land resource information, including a soil unit. Soil is one in an inventory of five physical factors (including rock, slope, erosion, and vegetation) delineated by physiographic polygons at approximately 1:50,000 scale. The NSD is a point database of soil physical, chemical, and mineralogical characteristics for over 1500 soil profiles nationally. A relational join between the NZLRI dominant soil and derivative tables from the NSD was the means by which 14 important soil attributes were attached to the NZLRI polygons. Some if these attributes originate from exact matches with NSD records, while others derive from matches to similar soils or professional estimates. This layer contains the particle size classification attribute. Particle size class describes in broad terms the proportions of sand, silt and clay in the fine earth fraction of the soil except in the case of skeletal soils ( > 35% coarse fraction ) where it applies to the whole soil. The classes are described in Webb and Wilson (1995) and the user should also refer to the item grav_class for a description of the topsoil gravel content of soils. For the 2nd Edition Gisborne-East Coast mapping, particle size is recorded as undefined as soils were mapped directly to the New Zealand Soil Classification.

Monthly water balance ratio data layer used in the creation of Land Environments of New Zealand (LENZ) classification. The classification layers have been made publicly available by the Ministry for the Environment (see data.mfe.govt.nz/layers/?q=LENZ for to access these layers).

This layer differentiates between regions that have minimal water deficit, but vary markedly in the total amount of rainfall they receive. Based on a water balance model using monthly estimates of mean daily temperature, mean daily solar radiation, and mean rainfall. This layer is the annual average of the monthly ratios of rainfall to potential evaporation calculated using the method of Priestley and Taylor (1972). The resulting 100 metre layer (The temperature, solar radiation and rainfall layers were all 100m) was then interpolated to 25 metres using bilinear interpolation.

The climate station data used in the development of this climate surface were derived from summaries of climate observations published by the New Zealand Meteorological Service, using data collected over the period from 1950-1980 The data layer was derived from surfaces fitted to monthly data describing daily average temperature, daily solar radiation and monthly rainfall. The rainfall surface was fitted using NZMG coordinates, elevation, and a model describing relationships between topography and westerly winds. Having derived the 36 input climate layers, an empirical model was first used to calculate the monthly potential evaporation from the monthly estimates of solar radiation and temperature. These estimates of evaporation were then compared with the monthly rainfall estimates. To calculate the monthly water balance ratio, the ratio of rainfall to evaporation was computed for each month, and then the average of these twelve ratios was calculated.

Additional details such as the climate station locations used in the creation of the layer are defined in the attached LENZ Technical Guide.

The New Zealand Fundamental Soil Layer originates from a relational join of features from two databases: the New Zealand Land Resource Inventory (NZLRI), and the National Soils Database (NSD). The NZLRI is a national polygon database of physical land resource information, including a soil unit. Soil is one in an inventory of five physical factors (including rock, slope, erosion, and vegetation) delineated by physiographic polygons at approximately 1:50,000 scale. The NSD is a point database of soil physical, chemical, and mineralogical characteristics for over 1500 soil profiles nationally. A relational join between the NZLRI dominant soil and derivative tables from the NSD was the means by which 14 important soil attributes were attached to the NZLRI polygons. Some if these attributes originate from exact matches with NSD records, while others derive from matches to similar soils or professional estimates. The layers contains the soil temperature regime attribute. The soil temperature regime classes relate to the soil temperature at 0.3 m depth. The classes used originate from and are described more fully in Webb and Wilson (1995), which in turn is based on the work of Aldridge (1982, 1984) and Aldridge and Cook (1983).

The NZLRI is a spatial database containing about 100,000 polygons (map units), each of which describes a parcel of land in terms of five characteristics or attributes (rock, soil, slope, erosion, vegetation). This layer represents a GIS dissolve on the vegetation attributes of the NZLRI.

The dataset contains polygons of soils of part northern Matamata County mapped at 1:50 000. The attributes contain the soil series and the soil classification. No analytical properties of the soil are included.

Induration data layer used in the creation of Land Environments of New Zealand (LENZ) classification. The classification layers have been made publicly available by the Ministry for the Environment (see data.mfe.govt.nz/layers/?q=LENZ for to access these layers).

Induration is a measure of how hard the soil is and is quantified by how much force is needed to break the soil. The data defines the induration based on the soil information (from the NZLRI) and the mapped parent material. This induration data layer is differentiated into five classes, Non-indurated (Class 1), Very weakly indurated (2), Weakly indurated (3), Strongly indurated (4), Very strongly (5). The class defined as "0" signifies areas where there are no soil attributes recorded (i.e. high peaks of the Southern Alps). Additional details such as discussion about the accuracy and reliability of the LENZ soil layers and the technical definitions of the categories in this layer are defined in the attached LENZ Technical Guide.

The New Zealand National Pasture Productivity map is a multi-temporal approach to estimating pasture (dry matter) yield in New Zealand's grassland area. The approach uses a model generated from collected historical records of pasture yield in 21 locations around New Zealand.It was hypothesised that yield of a paddock planted with pasture species would correlate with some average of normalised difference vegetation index (NDVI) observed at that location. The temporal median of NDVI of vegetated images across New Zealand's grasslands was obtained by calculating the median NDVI of all observations for each pixel where vegetation (NDVI > 0) was observed. Paddock polygons were manually created to surround each of the locations where yields had been obtained, and the spatial means within these polygons of the median NDVIs were plotted against the measured yields. A linear relationship between these quantities was created, which was applied to paddock polygons at a national scale. The uncertainty of the model is +/- 2.2 t/ha/yr for a 70% confidence interval.The data presented in this geodatabase is a segmentation of New Zealand grasslands using an automated multi-temporal approach presented by North, Pairman, and Belliss (2019). The parameters of this segmentation process were selected to achieve minimal missed boundaries between true paddock units. As a side-effect, some boundaries were created between sub-paddock areas with differing spectral response, such as in areas of strip grazing, areas divided by ridges or gullies, and areas with different management patterns. While these artefacts may improve the spatial accuracy of the pasture yield, the result is not intended to provide a one-to-one mapping between true paddock areas and their average pasture yield.The model was applied to each of these polygons. Because the data used to develop the initial model had generally high yields, the model has only been applied to polygons representative of higher-producing grasslands. Where median NDVI for a polygon was outside the domain of the assessed polygons, the model was deemed unfit to estimate pasture yield. Polygons with low median NDVI therefore have an assigned yield of zero.A full list of attribute definitions can be found in the attached PDF.The data used to generate the model has been derived from various published sources, in combination with Sentinel-2 imagery. Complete sets of Sentinel-2 for five passes covering mainland New Zealand were assembled and cloud-cleared in an automated manner using TMASK techinques. The resulting valid data was used to create medians of vegetated images on a per-pixel basis.The segmentation of New Zealand grasslands was derived by initially taking selected Sentinel-2 passes which gave suitable coverage of New Zealand's agricultural land, and applying the automated multi-temporal approach to boundary delineation. Around 200 passes from January - November 2018 were used to achieve the segmentation. These polygons were overlaid with the union of polygons from LCDB v5.0 (lris.scinfo.org.nz/layer/104400-lcdb-v50-land-cove...) which were either High-Producing or Low-Producing Grassland in both 2012 and 2018, and had not changed class between those dates.

DEPRECATED - THIS VERSION WAS SUPERCEDED FIRST BY VERSION 3.3 AND MORE RECENTLY BY VERSION 4.0 now available at lris.scinfo.org.nz/layer/412-lcdb-v40-land-cover-d...

This database is a thematic classification of land cover and land use classes. The current version 3 contains 33 classes designed to be compatible with earlier versions. The polygon features contain a code and boundary representing the land cover type at each of three periods; summer 1996/97, summer 2001/02, and summer 2008/09. The data set was designed to be compatible in scale and accuracy with Land Information New Zealand’s 1:50,000 topographic database. The land cover database is intended to be used in areas such as state of environmental monitoring, forest and shrubland inventory, biodiversity assessment, trend analysis and infrastructure planning.

The list of classes used in land cover database v3.0 can be found in the document LCDB2-3 Correlation Table along with the mapping from the class set used in the previous version (land cover database 2). This document is available as an attachment to this dataset (see below), and on the land cover database project site (www.lcdb.scinfo.org.nz).

The land cover database v3.0 was released in July 2012 and includes non-temporal edits to the summer 1996/97, summer 2001/02 time periods along with the new summer 2008/09 period. A change layer, “LCDB v3.0 change” (lris.scinfo.org.nz/layer/308-lcdb-v30-change) is available to indicate both non-temporal and temporal changes made between land cover database 2 and land cover database v3.0, The non-temporal changes include errors in the earlier mappings, step artefact removal, and coastline adjustments. An “authority” attribute is also available in this layer indicating the source of the change for both non-temporal and temporal changes mapped.

Funding is from the Ministry for Science and Innovation under contract CO9X1101, which was contributed to by the Ministry for the Environment. The Department of Conservation and individual regional councils and territorial authorities have made significant in kind contributions by checking the draft mapping for their areas of interest.

The Chatham Islands, which were available as part of land cover database2 on a different map projection, have not been re-mapped as part of land cover database v3.0.

Soilscapes are defined as "a landscape unit including a limited number of soil classes that are geographically distributed according to an identifiable pattern". These first approximation soilscapes are derived from legacy data and expert knowledge.

This layer comes from the Threatened Environment Classification (TEC) version 2012, which is a source of national scale background information on New Zealand's land environments. Specifically, it shows how much native (indigenous) vegetation remains within land environments, and how past vegetation loss and legal protection are distributed across New Zealand's landscape. The TEC uses indigenous vegetation as a surrogate for indigenous biodiversity. This includes indigenous ecosystems, habitats and communities: the indigenous species, subspecies and varieties that are supported by indigenous vegetation, and their genetic diversity. The TEC is most appropriately applied to help identify places that are priorities for formal protection against clearance and/or incompatible land-uses, and for ecological restoration to restore lost species, linkages and buffers. The TEC is a combination of three national databases: Land Environments New Zealand (LENZ), classes of the 4th Land Cover Database (LCDB4, based on 2012 satellite imagery) and the protected areas network (version 2012, reflecting areas legally protected for the purpose of natural heritage protection).

For more information see: Cieraad E, Walker S, Price R, Barringer J. 2015. An updated assessment of indigenous cover remaining and legal protection in New Zealand’s land environments. New Zealand Journal of Ecology 39(2).