151 Link Hall, Department of Civil and Environmental Engineering, Syracuse University, Syracuse NY 13244, United States.
E&S Environmental Chemistry, Corvallis, OR 97339, United States.
Sci Total Environ. 2015 Apr 1;511:186-94. doi: 10.1016/j.scitotenv.2014.12.044. Epub 2014 Dec 26.
Critical loads (CLs) and dynamic critical loads (DCLs) are important tools to guide the protection of ecosystems from air pollution. In order to quantify decreases in acidic deposition necessary to protect sensitive aquatic species, we calculated CLs and DCLs of sulfate (SO4(2-))+nitrate (NO3-) for 20 lake-watersheds from the Adirondack region of New York using the dynamic model, PnET-BGC. We evaluated lake water chemistry and fish and total zooplankton species richness in response to historical acidic deposition and under future deposition scenarios. The model performed well in simulating measured chemistry of Adirondack lakes. Current deposition of SO4(2-)+NO3-, calcium (Ca2+) weathering rate and lake acid neutralizing capacity (ANC) in 1850 were related to the extent of historical acidification (1850-2008). Changes in lake Al3+ concentrations since the onset of acidic deposition were also related to Ca2+ weathering rate and ANC in 1850. Lake ANC and fish and total zooplankton species richness were projected to increase under hypothetical decreases in future deposition. However, model projections suggest that lake ecosystems will not achieve complete chemical and biological recovery in the future.
临界负荷（CLs）和动态临界负荷（DCLs）是指导从空气污染中保护生态系统的重要工具。为了量化减少酸性沉降物以保护敏感水生物种，我们使用动态模型 PnET-BGC 计算了来自纽约阿迪朗达克地区的 20 个湖泊流域的硫酸盐（SO4(2-))+硝酸盐（NO3-）的 CLs 和 DCLs。我们评估了湖泊水质和鱼类和总浮游动物物种丰富度对历史酸性沉降物和未来沉降物情景的响应。该模型在模拟阿迪朗达克湖的实测化学物质方面表现良好。当前的 SO4(2-)+NO3-沉积、钙（Ca2+）风化速率和湖泊酸中和能力（ANC）在 1850 年与历史酸化程度（1850-2008 年）有关。自酸性沉降物开始以来，湖泊中 Al3+浓度的变化也与 1850 年的 Ca2+风化速率和 ANC 有关。假设未来沉积减少，预计湖泊 ANC 和鱼类和总浮游动物物种丰富度将增加。然而，模型预测表明，湖泊生态系统在未来不会实现完全的化学和生物恢复。
