S-map is a new digital soil spatial information system for New Zealand. It is being created by Manaaki Whenua with funding from central and local government.

S-map Online is one of a number of delivery services for S-map data and has been developed and is operated by Manaaki Whenua's Informatics team.


When complete across New Zealand, S-map will for the first time provide consistent and comprehensive national soil data layers to support applications at local, and regional to national scales. It builds on previous soil mapping by filling gaps with new mapping, and upgrading the information content and associated database to meet a new national standard. In time, S-map will have national coverage and contain predominantly new digital data at a scale that resolves soil variation on hill slopes (nominally 1:50 000 scale).

All outputs will have to meet specific S-map standards, which specify the soil attributes that are to be mapped and their level of description, including a measure of uncertainty. The primary map layer is soil classes, i.e. delineated areas that are labelled with the soil family name. Each soil family is defined as a unique combination of attributes (NZSC classification, parent material, rock type, dominant texture and permeability class). Soil classes are further characterised as siblings according to their depth to rock class, stoniness, land type, drainage, texture (more detailed), functional horizons and miscellaneous variant information. The uncertainty of each of these family and sibling attribute classes is specified.

Associated with the soil class layer will be additional map layers of fundamental and derived soil properties. The fundamental soil properties are depth (diggability), depth to slowly permeable layer, rooting depth, rooting barrier, horizon thickness, stoniness, clay and sand content. They are developed from sample information and expert knowledge. The derived soil layers are each based on a model (or pedo-transfer function). Some models are simple lookup tables that depend only on the soil class. Others combine various soil, land use, vegetation, climate or topographic attributes in a mathematical formula. Derived layers will include available water (mm), macroporosity, water retention, bulk density, total carbon, total nitrogen, phosphorus, calcium, cation exchange capacity, pH, and phosphorus retention.

You can find out more about S-map in the following paper:

Lilburne L, Hewitt A, Webb TH, Carrick S 2004. S-map: a new soil database for New Zealand. Proceedings of SuperSoil 2004: 3rd Australian New Zealand Soils Conference, Sydney, Australia.

and on the Soils Portal website at https://soils.landcareresearch.co.nz/tools/s-map-online/

Funding

Principal funding is through an Ministry of Business, Innovation and Employment (MBIE) contract to Manaaki Whenua's Characterizing Land Resources Portfolio.

Within this portfolio, S-map is being integrated with the related National Soils Database (a database of soil profile analyses) and other spatial datasets including the NZ Land Resource Inventory and the Fundamental Soil Data Layers (FSL).

MBIE funding alone will not be sufficient to provide the needed national coverage in reasonable time. For this reason cooperative arrangements are being sought with other agencies to advance the work programme (e.g., Regional Councils).

Stakeholders

Groups with a particular interest in new soil data include:

  • Territorial authorities for policy development, monitoring programmes and consent rules
  • Rural servicing agencies, farm managers and land owners – to provide information for management, planning, and standards certification
  • Science research programmes in which soil data underpin modelling and scaling up of research results, e.g., development of hydrological models in NIWA.

Methods

The work is divided into two major land areas:

  • Lowlands, dominantly flat to rolling land. Landforms are of such low relief that digital elevation models (based on current 20-m contour data) cannot be used for soil modelling. Soil mapping uses conventional methods, based on air-photo interpretation and free-survey techniques.
  • Uplands, dominantly hill and mountain terrain. Relief allows application of soil–landscape modelling based on digital elevation models and other spatial information. The actual modelling used will depend on the land system and the sampling cost and availability of data. The predominant technique will be to derive soil distribution rules from available data, literature and new sampling, and to apply these to modelled landform land-elements.

Work plan

S-map is currently being extended in the following areas:

  • Waikato region
  • Great Wellington region
  • Canterbury region
  • Hawke's Bay region

The initial work plan was based on developing the S-map infrastructure, and trialling mapping and soil classification in a range of contrasting landscapes and soils. The areas that are presently available in S-map Online are the test areas used to develop the S-map concepts and areas that have been funded directly by participating regional councils. Further areas are being added according to stakeholder needs.

 

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Last updated: 29 January 2018