{ "culture": "en-US", "name": "", "guid": "", "catalogPath": "", "snippet": "Summary This layer is a polygon-based zonal summary of erosion susceptibility indicators for 2 ha Digital River Network (DRN) watershed units across Northland. The symbology (erosion risk classes) of this layer is based on the attribute field \u201cErosion risk\u201d which is informed by combination of two factors - \u201cGeological risk\u201d and \u201cSediment runoff risk\u201d at 50:50 ratio.", "description": "

This vector dataset represents a polygonised summary of terrain, hydrological, and regolith susceptibility inputs across DRN watersheds (at 2ha drainage thresholds). It contains zonal statistics derived from continuous raster and classed surfaces, which were used to evaluate spatial variation in erosion susceptibility at sub-catchment scale (DRN 2ha watersheds).<\/SPAN><\/SPAN><\/P>

Key attributes include majority values from input rasters to S-PAL model (Sediment Process Attribute Layer) such as overland flow or \u201cSediment runoff risk\u201d, regolith activity or \u201cGeological risk\u201d, hydrological susceptibility or \u201cSoil permeability\u201d, as well as slope and elevation, S-PAL siblings.<\/SPAN><\/SPAN><\/P>

The symbology (erosion risk classes) of this layer is based on the attribute field \u201cErosion risk\u201d which is informed by combination of two factors - \u201cGeological risk\u201d and \u201cSediment runoff risk\u201d at 50:50 ratio.<\/SPAN><\/SPAN><\/P>

For details see the Land & Water Science report (Gunn and Rissmann 2025) - <\/SPAN><\/SPAN><\/P>

Northland Erosion and Sediment Risk Map - Metadata Report LWS 2026.pdf<\/SPAN><\/SPAN><\/A><\/P>

<\/P>

<\/P>

Attribute field | <\/SPAN>Field descriptions<\/SPAN>Multiple fields, see below:<\/SPAN><\/P>

Erosion Risk: <\/SPAN>1-5 categories (where 1 = low risk, and 5 = high risk) from composite of two factors - inherent \u201cGeological risk\u201d and \u201cSediment runoff risk\u201d at 50:50 ratio<\/SPAN>Geological Risk<\/SPAN><\/P>

A70_O30_Quantile_Majority to A30_O70_Quantiles_Majority: Majority susceptibility class (1-5) from combined susceptibility layers (at various proportions of regolith and OLF susceptibility e.g. 70% regolith and 30% OLF), where 1 = low susceptibility, 2 = moderately low susceptibility, 3 = moderate susceptibility, 4 = moderately high susceptibility, and 5 = high susceptibility.<\/SPAN><\/P>

Sibling_Class_Majority<\/SPAN>: Majority class from SPAL_4_12_35 raster<\/SPAN><\/P>

<\/P>

Author<\/SPAN>: Dr Clint Rissmann (Land & Water Science)<\/SPAN><\/P>

<\/P>

Extent<\/SPAN>: Whole Northland<\/SPAN><\/P>

Projection<\/SPAN>: NZTM (EPSG:2193)<\/SPAN><\/P>

Coarsest Scale of Component Dataset<\/SPAN>: 1:63,000 soil derived information<\/SPAN><\/P>

Version<\/SPAN>: Version 2.0<\/SPAN><\/P>

<\/P>

Date Created<\/SPAN>: July 2025<\/SPAN><\/P>

Date Modified<\/SPAN>: May 2026<\/SPAN><\/P>

<\/P>

NRC Team <\/SPAN>(if applicable): Natural Resources Science Team<\/SPAN><\/P>

Subject Matter Expert<\/SPAN>: Clint Rissmann \u2013 Landscape Scientist<\/SPAN><\/P>

<\/P>

File Size<\/SPAN>: 4.35 GB<\/SPAN><\/P>

<\/P>

Data Provided by<\/SPAN>: Manas Chakraborty (Resource Scientist - Freshwater)<\/SPAN><\/P><\/DIV><\/DIV><\/DIV><\/DIV>", "summary": "Summary This layer is a polygon-based zonal summary of erosion susceptibility indicators for 2 ha Digital River Network (DRN) watershed units across Northland. The symbology (erosion risk classes) of this layer is based on the attribute field \u201cErosion risk\u201d which is informed by combination of two factors - \u201cGeological risk\u201d and \u201cSediment runoff risk\u201d at 50:50 ratio.", "title": "Northland\u2019s Erosion and Sediment Risk map \u2013 catchment scale", "tags": [ "NRC", "Erosion Susceptibility", "Regolith Activity", "SPAL", "OLF", "Northland", "Continuous Index", "HEL" ], "type": "", "typeKeywords": [], "thumbnail": "", "url": "", "minScale": 20000000, "maxScale": 5000, "spatialReference": "", "accessInformation": "Land & Water Science; NRC", "licenseInfo": "