Waikato Regional Council obtains information on the number and type of stock on each farm in the Waikato region from the AgriBase database. AsureQuality New Zealand Ltd (formerly AgriQuality Ltd) developed, and now maintains, AgriBase.
We estimate the area of pastoral land on each farm from the Ministry for the Environment’s Land Cover Database4 < Land cover data supplied by Terralink NZ Limited. COPYRIGHT RESERVED.
Waikato Regional Council measures stock density across the Waikato region.
AsureQuality New Zealand Ltd maintains AgriBase records through:
Waikato Regional Council intends to purchase AgriBase every six months or as the need arises.
The Ministry for the Environment intends to update the LCDB every five years. Waikato Regional Council’s monitoring of pastoral area depends on the release of the updated LCDB by the Ministry for the Environment.
Development of the AgriBase system began in late 1988. National data capture began in 1993. Waikato Regional Council purchased a snapshot of the AgriBase database every six months since 2008.
The LCDB 4 data is primarily derived from SPOT 5 satellite imagery acquired between November 2011 and February 2013. More information is available from the dedicated Land Cover Database website.(external link)
Waikato Regional Council uses:
Waikato Regional Council calculates stock density for each farm by dividing the total stock units on the farm by the total area of pastoral land. Following this process for the whole region requires a series of steps, outlined below.
|Stock density class (stock units/ha)||Farm type where stock density class typically observed||Cows per hectare equivalent|
|Less than 10.5||Sheep farms||Less than 1.5|
|10.5 to 17.5||Beef farms and lower stocked dairy farms||1.5 to 2.5|
|17.5 to 24.5||Mid-range of dairy farms||2.5 to 3.5|
|Greater than 24.5||Higher stocked dairy farms||Greater than 3.5|
|Stock density not calculated||Reliable data not available|
|Farm Type||Class||Stock Units (SU) or ewe equivalent||Percent of each stock ‘typically’ found on farms (%)|
|Other (bulls etc)||5.5||2.4|
|Deer for Meat||1.8||30.2|
|Stags for velvet||2.1||5.3|
For example, the total stock units for dairy stock were calculated using the following formula:
Dairy Stock Units = (0.731 x Dairy numbers x 7) + (0.245 x Dairy numbers x 4.25) + (0.024 x Dairy numbers x 5.5).
To calculate stock density from AgriBase data, Environment Waikato uses the AsureQuality stock unit conversion factors. These factors are used to work out feed budgets in the agricultural industry.
AgriBase data cannot be used to calculate farm-based stock densities for all farms in the Waikato Region. This is because not all land parcels in the database are linked to a specific farm.
The AgriBase data purchased by Environment Waikato does not discriminate between the age classes of the animals. The equation used to calculate total stock units is a generalised one that uses typical stock classes on farms.
For information on the Land Cover Database data quality (lineage, positional accuracy, attribute accuracy, logical consistency and completeness) see the updated metadata for the LCDB available from the dedicated website – Land Cover Database.
A number of sophisticated quality assurance procedures (including statistical, SQL query, visual/spatial inspection) have been developed by AgriQuality New Zealand Ltd to verify the incoming data for AgriBase.
1.The LCDB 4 dataset is a 'public good' dataset owned by the Ministry for the Environment and supplied under Creative Commons V4 (external link)licensing
Supplied by AsureQuality New Zealand Ltd.