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Human-caused forest transitions are documented worldwide, especially during periods when land use by dense agriculturally-based populations intensified. However, the rate at which prehistoric human activities led to permanent deforestation is poorly resolved. In the South Island, New Zealand, the arrival of Polynesians c. 750 years ago resulted in dramatic forest loss and conversion of nearly half of native forests to open vegetation. This transformation, termed the Initial Burning Period, is documented in pollen and charcoal records, but its speed has been poorly constrained. High-resolution chronologies developed with a series of AMS radiocarbon dates from two lake sediment cores suggest the shift from forest to shrubland occurred within decades rather than centuries at drier sites. We examine two sites representing extreme examples of the magnitude of human impacts: a drier site that was inherently more vulnerable to human-set fires and a wetter, less burnable site. The astonishing rate of deforestation at the hands of small transient populations resulted from the intrinsic vulnerability of the native flora to fire and from positive feedbacks in post-fire vegetation recovery that increased landscape flammability. Spatially targeting burning in highly-flammable seral vegetation in forests rarely experiencing fire was sufficient to create an alternate fire-prone stable state. The New Zealand example illustrates how seemingly stable forest ecosystems can experience rapid and permanent conversions. Forest loss in New Zealand is among the fastest ecological transitions documented in the Holocene; yet equally rapid transitions can be expected in present-day regions wherever positive feedbacks support alternate fire-inhibiting, fire-prone stable states.

Understanding the evolutionary history and biogeography of the New Zealand alpine flora has been impeded by the lack of an integrated model of geomorphology and climate events during the Late Miocene, Pliocene and Pleistocene. A new geobiological model is presented that integrates rock uplift age, rate of uplift and the resulting summit elevations in the Southern Alps (South Island) during the last 8.0 million years with a climate template using the natural gamma radiation pattern from the eastern South Island Ocean Drilling Program Site 1119 that covers the past 3.9 million years. This model specifically defines the average treeline in relation to mountain height, allowing predictions as to the timing of the formation of the alpine zone and other open habitats. This model predicts open habitats such as rock bluffs, tussock grasslands and riverbeds would have been available from about 4.0–3.0 Ma, coinciding with the initiation of summit uplift and a cooling climate providing an opportunity for the evolution of generalist alpine and open-habitat herbs and shrubs. Alpine habitats began to form at about 1.9 Ma and were a permanent feature of the Southern Alps from about 0.95 Ma. Specialist alpine plants confined to alpine habitats can have evolved only within this period once the alpine zone was persistent and widespread. Bog habitats are likely to date from the Late Miocene (c. 6.0 Ma), and the specialist bog species would have evolved from this time. Molecular-clock dates for DNA sequences from species of specialist alpine habitats, generalist open habitats, and bog habitats are consistent with predictions made on the basis of the model.

Humans have altered natural patterns of fire for millennia, but the impact of human-set fires is thought to have been slight in wet closed-canopy forests. In the South Island of New Zealand, Polynesians (Māori), who arrived 700–800 calibrated years (cal y) ago, and then Europeans, who settled ∼150 cal y ago, used fire as a tool for forest clearance, but the structure and environmental consequences of these fires are poorly understood. High-resolution charcoal and pollen records from 16 lakes were analyzed to reconstruct the fire and vegetation history of the last 1,000 y. Diatom, chironomid, and element concentration data were examined to identify disturbance-related limnobiotic and biogeochemical changes within burned watersheds. At most sites, several high-severity fire events occurred within the first two centuries of Māori arrival and were often accompanied by a transformation in vegetation, slope stability, and lake chemistry. Proxies of past climate suggest that human activity alone, rather than unusually dry or warm conditions, was responsible for this increased fire activity. The transformation of scrub to grassland by Europeans in the mid-19th century triggered further, sometimes severe, watershed change, through additional fires, erosion, and the introduction of nonnative plant species. Alteration of natural disturbance regimes had lasting impacts, primarily because native forests had little or no previous history of fire and little resilience to the severity of burning. Anthropogenic burning in New Zealand highlights the vulnerability of closed-canopy forests to novel disturbance regimes and suggests that similar settings may be less resilient to climate-induced changes in the future.

Scientific knowledge production in the form of scientific publication is an increasingly connected and global endeavour, and institutional and funding pressures make it likely that studies addressing local questions may become less frequent and less obvious in the literature. We used the Scopus database and a focused subset of research published in ecological journals to evaluate trends in scientific publishing in New Zealand from 1980–2020 in the broad field of biological and environmental sciences. We evaluated research on New Zealand’s ecological systems by authors affiliated with a New Zealand institution and published in an ecological journal. In some ways, these bodies of research reflect widespread trends in science: increasing productivity, larger author teams, and increasing international connectivity. However, published research about New Zealand’s ecological systems has slowed compared to biological and environmental research published by New Zealand scholars. There have been changes through time in the subjects considered. For example, New Zealand-focused ecological publications have increasingly emphasised conservation and invasion biology. Likewise, there have been shifts in collaborations between different groups of institutes (e.g. universities and Crown Research Institutes) and the amount of research published by them. One outcome of these changes has been the development of a distinctive local literature (i.e. specific topics have retreated to local journals, while others have become internationalised). We conclude by considering some potential challenges that local journals face in the current publishing environment, and how a more resilient local ecological publishing community might be developed.

Background: Over 80% of New Zealand’s indigenous forests are in public ownership with logging prohibited, and logging of private indigenous forests is restricted to sustainable harvesting only. Such limitations are highly unusual globally and were imposed only in the last few decades of the 20th century. Previously, the national goal had been indigenous wood production in perpetuity. Here we review the role of forestry science in this outcome, and in particular in relation to the policies and practices adopted by the New Zealand Forest Service. Methods: Literature review Results: As early as 1900, it was recognised that economically viable management of indigenous forests for timber production was marginal at best. Nevertheless, the Forest Service, from its formation in 1919 to its abolition in 1987, advocated sustainable commercial management of indigenous forests. However, it failed to bring any significant areas under such management nor prevented conversion of substantial tracts of old-growth forest to exotic plantations or agriculture. Indigenous forest logging would have continued until commercial exhaustion of tall conifer species if a confluence of factors (urbanization, political upheaval, rise of an assertive conservation movement, and declining economic contribution) had not weakened the influence of provincial logging advocacy. Forestry research played a minor role in this saga as it focused on the technical issues of indigenous silviculture (e.g., coupe vs group vs single-tree harvesting methods) while the main drivers of change were economic, social, and cultural. Conclusions: Commercially valuable indigenous forests were protected only when the political cost of continuing logging was greater than that of halting it. However, it is an open question if the current policy settings will remain. Changes in governance (including increased Māori participation), land use change, planted indigenous forests and formation of exotic-indigenous forest communities will affect public attitudes as regards their use. If indigenous forestry science is to be of more consequence than in the past, New Zealand will need clear forestry goals and policies to deal with these changed circumstances, and the will to implement them.

For tens of millions of years the ratite moa (Aves: Dinornithiformes) were the largest herbivores in New Zealand’s terrestrial ecosystems. In occupying this ecological niche for such a long time, moa undoubtedly had a strong influence on the evolution of New Zealand’s flora and played important functional roles within ecosystems. The extinction of moa in the 15th century ce therefore marked a significant event in New Zealand’s biological history, not only in terms of biodiversity loss, but in the loss of an evolutionarily and ecologically distinct order of birds. Understanding the full extent and magnitude of this loss, and its implications for New Zealand ecosystems, depends upon a detailed knowledge of moa diets. Over the past 100 years, periodic discoveries of preserved moa gizzard content and coprolites (ancient preserved dung) have gradually begun to shed light on the diets of moa and their roles within New Zealand ecosystems. Here, we review how the study of such samples has shaped our understanding of moa diets through time. We then provide a synthesis of current knowledge about moa diets, including summarising 2755 records of plant remains from 23 moa gizzard contents and 158 moa coprolites. A clear picture is now emerging of distinct differences between the feeding ecologies of moa species, which together with differences in habitat preferences facilitated niche partitioning. Such insights provide empirical data to inform the debate surrounding the role of moa herbivory in the evolution of distinctive plant traits within the New Zealand flora. These data also help identify specific ecological functions and roles that have been lost due to the extinction of moa, and resolve to what extent these could be replaced via surrogate taxa.

In New Zealand, there are treelines of two main forms: abrupt southern beech treelines and gradual conifer–broadleaved treelines. At similar latitudes, abrupt treelines form at higher elevation than gradual treelines, but it is unclear whether this difference is also reflected in the climatic conditions experienced at the contrasting treeline ecotones. In this study, we measured soil and air temperatures across four gradual and two abrupt treelines ecotones in New Zealand for 2 years, and compared the climatic conditions between the treeline forms. Although gradual treelines form at lower elevations, they experience similar summer temperatures as the higher abrupt treelines. In contrast, temperatures in the shoulder season and during winter differed between sites of contrasting treeline forms. Soil scarcely froze and air temperature did not fall below −6°C at the gradual treeline sites, whereas freezing soils and snow were more common (extreme air frosts down to −9°C) at the abrupt treeline sites. Air and soil temperatures mirror the change in tree stature in the ecotone: with increasing altitude through the gradual treeline ecotone, temperature decreased gradually; whereas abrupt temperature changes were found at the abrupt treeline–grassland interface. These altitudinal patterns provide insights into potential mechanisms that drive treeline form and position, and their response to climatic change.

How and why organisms are distributed as they are has long intrigued evolutionary biologists. The tendency for species to retain their ancestral ecology has been demonstrated in distributions on local and regional scales, but the extent of ecological conservatism over tens of millions of years and across continents has not been assessed. Here we show that biome stasis at speciation has outweighed biome shifts by a ratio of more than 25:1, by inferring ancestral biomes for an ecologically diverse sample of more than 11,000 plant species from around the Southern Hemisphere. Stasis was also prevalent in transocean colonizations. Availability of a suitable biome could have substantially influenced which lineages establish on more than one landmass, in addition to the influence of the rarity of the dispersal events themselves. Conversely, the taxonomic composition of biomes has probably been strongly influenced by the rarity of species' transitions between biomes. This study has implications for the future because if clades have inherently limited capacity to shift biomes, then their evolutionary potential could be strongly compromised by biome contraction as climate changes.

Fire is a complex physical and ecological process and one that has dramatically affected New Zealand's landscapes and ecosystems in the post-settlement era. Prior to human settlement in the late 13th century, the Holocene palaeoenvironmental record suggests that fire frequencies were low across most of New Zealand, with the notable exception of some wetland systems. Because few of New Zealand's indigenous plant species show any real adaptation to fire, the greatly increased fire activity that accompanied human settlement resulted in widespread, and in some cases permanent, shifts in the composition, structure and function of many terrestrial ecosystems. The combined effects of Maori and European fire have left long-lasting legacies in New Zealand's landscapes with the most obvious being the reduction of forest cover from 85–90% to 25% of the land area. Here we review the long-term ecological history of fire in New Zealand's terrestrial ecosystems and describe what is known about the fire ecology of New Zealand's plant species and communities, highlighting key uncertainties and areas where future research is required. While considerable emphasis has been placed on describing and understanding the 'initial burning period' that accompanied Maori arrival, much less ecological emphasis has been placed on the shifts in fire regime that occurred during the European period, despite the significant effects these had. Post-fire successional trajectories have been described for a number of wetland and forest communities in New Zealand, but in contemporary landscapes are complicated by the effects of exotic mammalian species that act as seed and seedling predators and herbivores, reduced pollination and dispersal services due to declines in the avifauna, and the presence of pyrophyllic exotic plant species. Many invasive plant species (e.g. Pinus spp., Acacia spp., Hakea spp., Ulex europaeus) are favoured by fire and now co-occur with indigenous plant species in communities whose long-term composition and trajectory are unclear. On the other hand, some highly-valued ecosystems such as tussock grasslands may require recurrent fire for their long-term persistence. Combined, the direct and indirect effects of the introduction of anthropic fire to New Zealand may have shifted large areas into successional 'traps' from which, in the face of recurrent fire, escape is difficult. Developing appropriate management strategies in such a context requires a nuanced understanding of the place of fire in New Zealand's ecosystems.

The Proceedings of the Ecological Society of New Zealand (PESNZ) and its continuation, the New Zealand Journal of Ecology (NZJE), published more than 1250 articles over the 58 years from 1961–2019. Over this period, the emphasis of ecology as a science and the social context in which it is embedded have changed. Here we provide a bibliometric analysis of the history of the PESNZ and the NZJE to assess how the dominant research themes have changed through time, and the extent to which they reflect broader trends in the policy and funding landscapes. The journals’ consistent focus has been on applied ecological issues, especially the effects and control of invasive mammals. However, the most discussed taxa have shifted over time (from deer to brushtail possums to rodents and mustelids). Collaboration has altered dramatically, with few author networks and single-author articles in early issues versus multi-author articles and widespread networks today. Thus, the research published by the Society reflects NZ-specific concerns and broader trends in knowledge production (e.g. the shift to team-based science). We conclude by considering the publications of the NZ Ecological Society through the lens of journals being ‘clubs’ for the social production of shared knowledge.