Natural grasslands are among the most threatened biomes on Earth. They are under pressure from land cover change including afforestation, farming intensification, invasive species, altered fire regimes, and soil amendments, all of which impact native biodiversity and ecosystem functioning. In Aotearoa New Zealand, tussock-dominated native grasslands expanded due to increased fire activity during waves of human settlement. These areas have subsequently been maintained as modified grasslands by agricultural pastoral land management practices and effects of introduced feral mammals.
Anthropogenic fire has transformed New Zealand’s vegetation. Small-scale historical Māori fires in the forests of Te Urewera National Park, North Island, initiated forest successions that were dominated early on by Kunzea ericoides (Myrtaceae), and later by Knightia excelsa (Proteaceae) and Weinmannia racemosa (Cunoniaceae). Previous work in these forests suggested that the more recent of these successions, initiated after the arrival of deer in the late 19th century, have failed to recover to pre-fire composition and structure.