【摘要】 本文用在加拿大诺瓦·斯科舍省芬克湾采集到的两只活体偏顶蛤（Modiolus）贝壳上的氧同位素组成重建了过去十年间的底层海水温度记录,它也可作为一种独立的方法来确定贝壳上外生长线的沉积时间。由于对贝壳进行了密集采样（可多至每个贝壳沉积年份取15个样品）,贝壳上的δ¹⁶O变化反映了芬克湾底层海水的季节性变化。两只贝壳所得的温度剖面符合得很好,说明它们基本上是与真实的环境温度相对应的。本研究证明在海胆疾病爆发时底层海水的温度并没有异常升高,这说明疾病传播的关键因素是带病的生物体,而不是温度。同位素技术也说明了在贝壳外表面上可见的外生长线是年轮性的,它们是在每年冬季最低水温时沉积出来的。更多还原

【Abstract】 A time series of δ¹⁸O values from two Modiolus shells, collected in Fink Cove, Nova Scotia, Canada, were used to reconstruct bottom water temperatures and as an independent method to examine the timing of deposition of external growth lines. A fine scale of resolution was achieved, with up to 15 discrete samples per year of shell deposition. Records from two shells showed similar trends. The δ¹⁸O values of the shells clearly tracked seasonal temperatures.Someone presented a hypothesis that the sea urchin disease, which devastated populations along the Atlantic Coast of Nova Scotia in 1980-1983, was temperature related. This study provides evidence that seawater temperatures were not unusually warm during the start of urchin mortalities. It suggests that availability of the disease-causing organism, rather than temperature was the critical factor in the spread of the disease. This isotope technique revealed that growth lines, visible on the exterior of the shell, are annual events which occur at the same time each year during the winter temperature minima.更多还原