A goal of the New Zealand Biodiversity Strategy is to ‘halt the decline in New Zealand’s indigenous biodiversity, and to maintain and restore a full range of remaining natural habitats and ecosystems to a healthy functioning state’. Meeting this goal requires knowledge of how much of the full range of natural ecosystems remains, and how well they and their biodiversity components are protected. However, reliable information is surprisingly difficult to bring together at a national level.
One way to assess broad patterns of loss and protection of indigenous species habitats is to combine maps of land cover, legal protection status and the abiotic environment. The first such combination analysis was produced nearly 10 years ago, and was used to create a simple, six-category ‘Threatened Environment Classification’ that has been adopted by many agencies, decision-makers and private biodiversity practitioners across the country.
Recently, my colleagues and I revised and published an updated Classification with updated land cover (LCDB4.0; based on 2012 satellite imagery) and information on protected areas for natural heritage purposes (2012), which they combined with LENZ (Land Environments New Zealand). You can find our paper here. The new analysis shows that New Zealand’s lowest, flattest, warmest and driest environments have lost high proportions of their indigenous cover and what remains is poorly protected ‒ even less so than previously estimated. In contrast, the highest, steepest, coolest, and wettest environments have been less reduced by human land use and are much better protected ‒ more so than previously estimated.
Cieraad E, Walker S, Price R, Barringer J 2015. An updated assessment of indigenous cover remaining and legal protection in New Zealand’s land environments. New Zealand Journal of Ecology 39(2): 309-315.
The Threatened Environment Classification provides a high-level, standardised national framework for assessing biodiversity representativeness and protection that and can assist both planning and reporting. Land in the first two categories of the classification (less than 20% indigenous cover remaining) is recognised as a priority in biodiversity protection policy, especially on private land. In combination with site survey, the Classification can help resource managers to identify places that are priorities for formal protection against clearance and/or incompatible land uses, and for ecological restoration to restore linkages, buffers and lost species.
The Threatened Environment Classification is freely available, and can be accessed in several ways. The easiest way to view it and create maps is in Landcare Researches GIS portal Our Environment (under “About Ecosystems and habitats” tick “Which areas of indigenous vegetation are under threat?”).
More information and resources are available on http://www.landcareresearch.co.nz/resources/maps-satellites/threatened-environment-classification