Analysis of New Zealand Vegetation Cover Using Land Resource Inventory Data

An analysis of New Zealand's vegetation cover is presented, based on vegetation information from the New Zealand Land Resource Inventory. This survey, undertaken between 1973 and 1979, recorded vegetation in homogeneous land inventory map units as part of a physical resource inventory, using a classification of 45 vegetation components covering indigenous and introduced vegetation cover.

The analysis is presented within the framework of a classification of New Zealand's vegetation cover, which is a functional grouping of the most common combinations of vegetation mapped. The classification emphasises the number of significant components o of vegetation cover within map units rather than their importance or dominance. The total o of 6863 different combinations of vegetation cover recorded in 89875 map units have been aggregated into 232 primary units of vegetation cover, termed vegetation cover categories. These were grouped into 88 vegetation cover classes and II vegetation cover groups. The latter, identifying the components of New Zealand's vegetation cover at the broadest level were as follows: grassland (22.5% of the New Zealand land area), grassland-cropland (8.2 %), scrubland and fernland (2.2%), forest (18.3%), forest-scrub (7.7%), grassland-scrub (26%), grassland with forest (3% forest with grassland (0.7%), grassland-scrub-forest (5.3%), miscellaneous (2.2%), no vegetation (3.9%).

The analysis is briefly discussed and compared with other available information. The comparatively detailed analysis of grassland and scrubland vegetation has revealed the large extent of mixed vegetation cover, especially grassland-scrub mixtures. It is concluded that the analysis confirms the dynamic and complex nature of New Zealand's present vegetation cover.