ABSTRACT

Dune systems in Atlantic Canada are relatively small given a relatively low sediment supply. The dunes are built primarily of reworked sediments as relative sea level (RSL) has risen. The foredune (at least) is reworked several times a decade by extreme weather events and many are transgressing on a decadal scale as a result of normal geomorphic processes. The key drivers shaping the dunes are, however, changing over time with climate change.The rate of RSL rise is accelerating, which will almost certainly mean an acceleration of dune transgression rates. As well, there is some evidence that storms are becoming more frequent and sea ice is diminishing, meaning more frequent reactivation.

Predicting how dunes will respond to changes in the key controlling variables on an annual or decadal scale is challenging. Examination of how the dunes evolve on a decadal to century scale, however, suggests that the dunes in Atlantic Canada should continue to exist. Thus, we advocate using a dune management approach that focuses on minimizing human impacts and allowing natural processes to continue unimpeded. The highest priority for managing our coastal dunes should be to provide them with sufficient accommodation space into which they can transgress naturally.

摘要

由于沉积物供应相对较低，加拿大大西洋的沙丘系统相对较小。随着相对海平面（RSL）的上升，沙丘主要由经过改造的沉积物构成。极端天气事件（至少）十年内多次改造前缘，并且由于正常的地貌过程，许多都在十年尺度上越界。然而，塑造沙丘的关键驱动因素随着时间的推移随着气候变化而变化。RSL 上升的速度正在加快，这几乎肯定意味着沙丘入侵率的加速。同样，有一些证据表明风暴变得更加频繁，海冰正在减少，这意味着更频繁的重新激活。

预测沙丘将如何应对年度或十年范围内关键控制变量的变化具有挑战性。然而，对沙丘如何在十年到世纪尺度上演变的研究表明，加拿大大西洋的沙丘应该继续存在。因此，我们提倡使用沙丘管理方法，专注于最大限度地减少人类影响并让自然过程继续畅通无阻。管理我们的沿海沙丘的首要任务应该是为它们提供足够的住宿空间，让它们可以自然越过。