Imagined landscapes find their form in utopian dreaming. As ideal places, utopias are set up according to the ideals of their designers. Inevitably, utopias become compromised when they move from the imaginary into the actual. Opportunities to create utopias rely largely on a blank slate, a landscape unimpeded by the inconveniences of existing occupation – or even topography. Christchurch has seen two utopian moments. The first was at the time of European settlement in the mid-nineteenth century, when imported ideals provided a model for a new city. The earthquakes of 2010 and 2011 provided a second point at which utopian dreaming spurred visions for the city. Christchurch’s earthquakes have provided a unique opportunity for a city to re-imagine itself. Yet, as is the fate for all imaginary places, reality got in the way.
Tree mortality is a fundamental process governing forest dynamics, but understanding tree mortality patterns is challenging
because large, long-term datasets are required. Describing size-specific mortality patterns can be especially difficult, due to
few trees in larger size classes. We used permanent plot data from Nothofagus solandri var. cliffortioides (mountain beech)
forest on the eastern slopes of the Southern Alps, New Zealand, where the fates of trees on 250 plots of 0.04 ha were
followed, to examine: (1) patterns of size-specific mortality over three consecutive periods spanning 30 years, each
characterised by different disturbance, and (2) the strength and direction of neighbourhood crowding effects on sizespecific
mortality rates. We found that the size-specific mortality function was U-shaped over the 30-year period as well as
within two shorter periods characterised by small-scale pinhole beetle and windthrow disturbance. During a third period,
characterised by earthquake disturbance, tree mortality was less size dependent. Small trees (,20 cm in diameter) were
more likely to die, in all three periods, if surrounded by a high basal area of larger neighbours, suggesting that sizeasymmetric
competition for light was a major cause of mortality. In contrast, large trees ($20 cm in diameter) were more
likely to die in the first period if they had few neighbours, indicating that positive crowding effects were sometimes
important for survival of large trees. Overall our results suggest that temporal variability in size-specific mortality patterns,
and positive interactions between large trees, may sometimes need to be incorporated into models of forest dynamics.
Orientation: Large-scale events such as disasters, wars and pandemics disrupt the economy by diverging resource allocation, which could alter employment growth within the economy during recovery.
Research purpose: The literature on the disaster–economic nexus predominantly considers the aggregate performance of the economy, including the stimulus injection. This research assesses the employment transition following a disaster by removing this stimulus injection and evaluating the economy’s performance during recovery.
Motivation for the study: The underlying economy’s performance without the stimulus’ benefit remains primarily unanswered. A single disaster event is used to assess the employment transition to guide future stimulus response for disasters.
Research approach/design and method: Canterbury, New Zealand, was affected by a series of earthquakes in 2010–2011 and is used as a single case study. Applying the historical construction–economic relationship, a counterfactual level of economic activity is quantified and compared with official results. Using an input–output model to remove the economy-wide impact from the elevated activity reveals the performance of the underlying economy and employment transition during recovery.
Main findings: The results indicate a return to a demand-driven level of building activity 10 years after the disaster. Employment transition is characterised by two distinct periods. The first 5 years are stimulus-driven, while the 5 years that follow are demand-driven from the underlying economy. After the initial period of elevated building activity, construction repositioned to its long-term level near 5% of value add. Practical/managerial implications: The level of building activity could be used to confidently assess the performance of regional economies following a destructive disaster. The study results argue for an incentive to redevelop the affected area as quickly as possible to mitigate the negative effect of the destruction and provide a stimulus for the economy. Contribution/value-add: This study contributes to a growing stream of regional disaster economics research that assesses the economic effect using a single case study.
We examined the stratigraphy of alluvial fans formed at the steep range front of the Southern Alps at Te Taho, on the north bank of the Whataroa River in central West Coast, South Island, New Zealand. The range front coincides with the Alpine Fault, an Australian-Pacific plate boundary fault, which produces regular earthquakes. Our study of range front fans revealed aggradation at 100- to 300-year intervals. Radiocarbon ages and soil residence times (SRTs) estimated by a quantitative profile development index allowed us to elucidate the characteristics of four episodes of aggradation since 1000 CE. We postulate a repeating mode of fan behaviour (fan response cycle [FRC]) linked to earthquake cycles via earthquake-triggered landslides. FRCs are characterised by short response time (aggradation followed by incision) and a long phase when channels are entrenched and fan surfaces are stable (persistence time). Currently, the Te Taho and Whataroa River fans are in the latter phase. The four episodes of fan building we determined from an OxCal sequence model correlate to Alpine Fault earthquakes (or other subsidiary events) and support prior landscape evolution studies indicating ≥M7.5 earthquakes as the main driver of episodic sedimentation. Our findings are consistent with other historic non-earthquake events on the West Coast but indicate faster responses than other earthquake sites in New Zealand and elsewhere where rainfall and stream gradients (the basis for stream power) are lower. Judging from the thickness of fan deposits and the short response times, we conclude that pastoral farming (current land-use) on the fans and probably across much of the Whataroa River fan would be impossible for several decades after a major earthquake. The sustainability of regional tourism and agriculture is at risk, more so because of the vulnerability of the single through road in the region (State Highway 6).
