EcoSat and LCDB

Severe erosion in southern Hawkes Bay following a major storm in 2011. Image - Les Basher

What is the difference between EcoSat and LCDB (Land Cover Database)?

The table below contrasts EcoSat with the LCDB. Although both systems use satellite imagery to produce land information at 1:50 000 scale, they are different in many aspects. LCDB was designed primarily to report on changes to land cover and therefore has needed to maintain the mapping standards established for the LCDB1 (e.g., 1 ha minimum mapping unit). EcoSat in contrast has been free to use new technology and develop different standards for a variety of products. These products have been designed to complement LCDB. For example, EcoSat basic land cover maps actual land cover, whereas LCDB focusses more on land use (e.g., recently cleared forest in an exotic forest estate is mapped by EcoSat as bare ground, whereas it is mapped by LCDB as exotic forest). EcoSat does not attempt to produce a single snapshot in time, like LCDB, but has built up a national coverage of ETM+ imagery over 4 years. Thus it has been possible to archive high quality imagery with relatively high sun angles and low cloud cover. The high sun angles have permitted the flattening of imagery and the automatic processing to products with 15-m pixel minimum mapping unit.

Summary table
EcoSat	LCDB2
Products
15 m ortho-rectified imagery 15 m standardised spectral reflectance (calibrated and flattened imagery) 15 m woody vegetation layer 15 m basic land cover (15 classes) 15 m ecosystem energy absorption 15 m water courses and riparian vegetation 15 m DEM 15 m indigenous forest composition 15 m wetlands (16 classes)	Corrected LCDB1 (18 classes) LCDB2 layer (42 classes) 15m ortho-rectified imagery Land cover change map (1997-2002)
Minimum mapping unit
225 m2	10000 m2
Geo-registration accuracy
10 m	10 m
Primary uses
Regional forest inventory Possum control monitoring Regional land-cover inventory Regional riparian vegetation inventory Land condition monitoring Regional wetland inventory	National forest inventory Kyoto protocol reporting National land-cover inventory and 5 yearly change map/statistics SOE reporting National–Local National wetland inventory > 1 ha Significant indigenous vegetation (RMA S6c)
Production methods
Atmospheric, directional reflectance, and topographically corrected imagery Automatic per pixel classification Objective reflectance rules	Manual drawing of LCDB1 polygons by visual interpretation Corrected LCDB1 and LCDB2 change polygons automatically drawn or manually drawn Intensive ground data and field verification required as not all classes are spectrally separable
Acquisition period
Best recent imagery over last 4 summers Region by region approach	2001–2002 summer imagery National snapshot every 5 years Includes off-shore islands
Distribution
Regional partnerships contribute to cost of production. Ownership remains with LCR	A publicly accessible Crown database

EcoSat and LCDB

What is the difference between EcoSat and LCDB (Land Cover Database)?

Summary table