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• Hazard zone methodology: The paper employs a hazard zone methodology, typically used for managing erosion risk to modern infrastructure, to assess and manage the risk to coastal archaeological heritage. • Coastal archaeological heritage at risk: Coastal archaeological heritage in Aotearoa/New Zealand is under threat from coastal erosion, with accelerated risk due to rising sea levels. • Projected sea-level rise impact: The study predicts that a relatively modest 20 cm of sea-level rise, expected by 2040, may put around 8 % (155) of coastal archaeological sites at risk, and a more significant 1 m of sea-level rise could threaten approximately 19 % (356) of sites. • Connection to indigenous communities: The coastal archaeological heritage is closely tied to Māori, the indigenous ancestral communities of Aotearoa/New Zealand. • Adaptive planning pathways: Scenarios are presented to assist stakeholders in assessing heritage risk, providing an opportunity for coastal managers to incorporate heritage considerations into adaptive planning pathways. Coastal archaeological heritage is in danger of being lost to coastal erosion, the risk of which is amplified by accelerating sea-level rise (SLR). In Aotearoa/New Zealand, coastal archaeological heritage is closely associated with indigenous ancestral communities, but our understanding of the spatiotemporal variability in coastal erosion risk for cultural heritage is limited. Coastal erosion hazard zones have typically been implemented to manage erosion risk to modern infrastructure at regional scales. In this study, we applied a hazard zone methodology in the context of coastal archaeological heritage for a selected region of Aotearoa (Te Tai Tokerau/Northland). Historical coastal change analyses reveal that most beaches in the region have been stable or slightly accretionary over the past ∼80 years, but a reversal of this trend is likely under the projected SLR, which is expressed in the coastal erosion hazard zones. Our analyses indicate that ∼8 % (155) of coastal archaeological sites in Te Tai Tokerau/Northland may be at risk of erosion with a relatively modest 20 cm of SLR, which is expected for the region by 2040, and ∼19 % (356) of sites are threatened by 1 m of SLR. Scenarios are presented that should assist a broad range of stakeholders to assess heritage risk and provide an opportunity for coastal managers to include heritage within adaptive planning pathways. [ABSTRACT FROM AUTHOR]

Coastal sand dunes are multifunctional landscapes with rich biodiversity. In New Zealand, with the establishment of European settlement around 1840, dunes in the Manawatu-Whanganui region were affected due to the removal of their vegetation cover by human activities and animal grazing. As a result, sand drifted further inland affecting villages, infrastructure and agricultural areas. The main response was to introduce marram grass (Ammophila arenaria) used in Europe to stabilize dunes. This solution caused significant environmental impacts as marram grass turned invasive and native habitats of fauna and flora significantly decreased. This paper focused on the long-term analysis of aspects related to sand dune management in the region during two-time frames: 1) from the 19th to the late 20th century and 2) from then on to the early 21st century, using the innovative spiral DPSIR (Driver-Pressure-State-Impact-Response) framework. Data for this study comes from historical records, scientific literature and present management reports. The integrated spiral framework allows for establishing the connections between historical and future management initiatives for mitigating and adapting to environmental impacts due to socio-economic drivers and their pressures. The study reinforces the paradigm shift from dune stabilization before the late 20th century to the restoration of stabilized dunes to make them active for enhancing native biodiversity should be again assessed in the context of sea-level rise during this century. Coastal managers should adopt an optimized solution between these two extreme solutions adopted from the 19th century to the present, by considering long-term and interdisciplinary analysis to better understand the systems' evolution and the full consequences of human actions. • The spiral DPSIR framework is proposed to analyse long-term environmental issues. • The spiral framework can represent the cause and effect of new and old components. • It can be used to study historical and future environmental management initiatives. • The long-term effect of dune management responses is a key for policy development. • Coastal flood mitigation may compromise the dune biodiversity conservation efforts. [ABSTRACT FROM AUTHOR]

Abstract: Positive deviations from linear sea-level trends represent important climate signals if they are persistent and geographically widespread. This paper documents rapid sea-level rise reconstructed from sedimentary records obtained from salt marshes in the Southwest Pacific region (Tasmania and New Zealand). A new late Holocene relative sea-level record from eastern Tasmania was dated by AMS14C (conventional, high precision and bomb-spike), 137Cs, 210Pb, stable Pb isotopic ratios, trace metals, pollen and charcoal analyses. Palaeosea-level positions were determined by foraminiferal analyses. Relative sea level in Tasmania was within half a metre of present sea level for much of the last 6000yr. Between 1900 and 1950 relative sea level rose at an average rate of 4.2±0.1mm/yr. During the latter half of the 20th century the reconstructed rate of relative sea-level rise was 0.7±0.6mm/yr. Our study is consistent with a similar pattern of relative sea-level change recently reconstructed for southern New Zealand. The change in the rate of sea-level rise in the SW Pacific during the early 20th century was larger than in the North Atlantic and could suggest that northern hemisphere land-based ice was the most significant melt source for global sea-level rise. [Copyright &y& Elsevier]