Abstract Stager JC, Wiltse B, Cumming BF, Holsen TM, Stetler J, Laxson C, Marcillo CE, Charles DF. 2019. A novel ecological state at Bear Pond (Adirondack Mountains, NY, USA) following acidification and partial recovery. Lake Reserv Manage. 35:208–223. The pH of precipitation in the northeastern United States has risen as industrial sulfur and nitrogen oxide emissions have declined following amendment of the Clean Air Act in 1990, but the effects of this change on the region's lakes are not yet fully documented. Here we use the siliceous remains of diatoms and chrysophyte algae in a sediment core from Bear Pond (Adirondack State Park, NY), which acidified during the 20th century, to reconstruct pH variability during the last 2 centuries, evaluate the extent to which the lake has recovered from acidification, and determine the timing of that reversal to help identify its causes. Inferred pH declined erratically from a high of 6.4 during the 1860s to 5.7–5.9 during the 1930s, then decreased to the 4.9–5.4 range by 1995–2010. After 2010, inferred pH rose and remained within the 5.4–5.6 range following an abrupt rise in the pH of regional precipitation. Although the acidification trend at Bear Pond has now reversed, the lake ecosystem has not returned to its pre-impact condition. Distinctive members of the pre-acidification diatom community are still absent, chrysophytes have become unusually abundant, and water clarity (Secchi depth) has decreased by about half. Furthermore, the original fish community was lost due to stocking and piscicide treatment in 1958, and high concentrations of toxaphene residues from the piscicide are present in the sediments. Full ecological restoration of formerly acidic lakes such as Bear Pond may be unlikely due to complicating factors such as climate change and fisheries management practices.

中文翻译：

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酸化和部分恢复后熊池（美国纽约州阿迪朗达克山脉）的新生态状态

摘要 Stager JC、Wiltse B、Cumming BF、Holsen TM、Stetler J、Laxson C、Marcillo CE、Charles DF。2019. 酸化和部分恢复后 Bear Pond（美国纽约州阿迪朗达克山脉）的新生态状态。湖泊保护区管理。35:208-223。1990 年《清洁空气法案》修订后，随着工业硫和氮氧化物排放量的下降，美国东北部降水的 pH 值有所上升，但这种变化对该地区湖泊的影响尚未完全记录。在这里，我们使用 20 世纪酸化的 Bear Pond（纽约州阿迪朗达克州立公园）沉积物芯中的硅藻和金藻藻类的硅质残留物来重建过去 2 个世纪的 pH 值变化，评估湖泊已从酸化中恢复，并确定逆转的时间以帮助确定其原因。推断的 pH 值不规则地从 1860 年代的 6.4 高点下降到 1930 年代的 5.7-5.9，然后在 1995-2010 年下降到 4.9-5.4 范围。2010 年之后，随着区域降水 pH 值的突然上升，推断的 pH 值上升并保持在 5.4-5.6 范围内。虽然现在熊塘的酸化趋势已经逆转，但湖泊生态系统并没有恢复到撞击前的状态。预酸化硅藻群落的独特成员仍然不存在，金藻变得异常丰富，水的透明度（Secchi 深度）减少了大约一半。此外，由于 1958 年的放养和杀鱼剂处理，原始鱼类群落消失，沉积物中存在高浓度的杀鱼剂毒杀芬残留物。