The emerging threat of Ca decline: quantifying current and predicting future Ca levels and their effects on aquatic biota in a 1600 lake watershed

土壤、溪流、池塘和湖泊水钙浓度的持续下降对加拿大东部地盾的森林和湖泊构成了新的威胁，但我们目前没有量化这种威胁的严重性和空间范围所需的信息，也不知道这种威胁如何受到持续的森林火灾和伐木干扰的影响。在这个由地理空间统计学家、水生生态毒理学家和两名流域生物地球化学家组成的新合作中，我们将：1)评估目前在1600个安大略湖流域一个重要的富钙生物群（动物浮游生物）的威胁；2)量化未来酸沉降速率与国际二氧化硫允许排放协议、与气候变化相关的森林火灾频率以及伐木行为如何改变钙下降的威胁。碳的减少是一个新出现的环境问题，但它可能会影响到加拿大东部的大片森林和地表水，以及美国东部和西欧类似的生态系统。我们的目标是在一个敏感的流域确定这种威胁的严重程度，作为评估Ca下降问题对加拿大可能变得多么严重的必要的第一步。

The ongoing decline of soil, stream, pond and lake water Ca concentrations poses an emerging threat to the forests and lakes of the eastern Canadian Shield, but we currently do not have the information needed to quantify the severity and spatial extent of this threat, nor do we know how this threat might be affected by ongoing forest disturbances of fire and logging. In this new collaboration of a geospatial statistician, an aquatic ecotoxicologist, and two watershed biogeochemists, we will: 1) assess the current threat of Ca decline to one important group of Ca-rich biota (the animal plankton) in a large 1600-lake Ontario watershed; and 2) quantify how future acid deposition rates linked to international agreements on allowable SO2 emissions, forest fire frequencies linked to a changing climate, and logging practises might alter the threat of Ca decline. Ca decline is an emerging environmental issue, but one that might affect large tracts of eastern Canadian forests and surface waters, and similar ecosystems in the eastern USA and western Europe. Our objective is to determine the severity of this threat in one sensitive watershed as a necessary first step in assessing how serious the issue of Ca decline might become for Canada.