Unique slices of time: Salvaging New Zealand sub-fossil kauri (Agathis australis) that span the termination of the Last Glacial Period

最后一次冰期的结束对气候和环境的突然和极端变化的机制提供了宝贵的见解。不幸的是，尽管有大量来自世界各地的冰、海洋和陆地记录跨越了这一时期，但由于12590年前缺乏强有力的陆地校准，精确的比较受到了阻碍。我们已经确定了一个新的地点，新西兰的Towai农场，在那里我们之前发现了4棵亚化石树，它们都属于较年轻的仙女木年代的最后一次冰川的终止，这是已知的突然和极端的气候变化时期。随着北部地区持续干旱(目前估计农业生产损失3亿新西兰元)，地下水位大幅下降，又有12棵树暴露在被开采出售给木材商人的过程中。这些kauri比例巨大，几乎保存完好；每棵树的直径长达2.2米，表明它们的寿命长达2000年。在这个珍贵的档案中，有一份关于大气放射性碳水平和过去气候变化的年度记录。这些树的树龄和时间跨度在世界上是独一无二的，因此是具有国际意义的资源。这个紧急奖是为了在Towai Farm Kauri永远消失之前为更广泛的科学界打捞和存档而需要的。

The end of the last glacial period provides valuable insights into the mechanisms of abrupt and extreme climatic and environmental change. Unfortunately, although there are numerous ice, marine and terrestrial records from around the world that span this period, precise comparisons are hampered by the absence of a robust terrestrial calibration before 12,590 years ago. We have identified a new site, Towai Farm, New Zealand, where we have previously recovered 4 sub-fossil trees that all fall within the termination of the last glacial during the Younger Dryas Chronozone, a period of known abrupt and extreme climate change. With the ongoing drought in Northland (currently estimated to cost NZ$300 million in lost agricultural production), the greatly lowered water table has exposed a further 12 trees that are in the process of being extracted for sale to timber merchants. These kauri are of vast proportions and almost perfectly preserved; individual trees measure up to 2.2 metres across, suggesting they lived up to 2000 years. Within this precious archive is an annual record of changing atmospheric radiocarbon levels and past climate. The age and timespan of these trees are unique in the world and therefore a resource of international significance. This Urgency Award is required to salvage and archive the Towai Farm kauri for the wider scientific community before it is lost forever.