摘要
在过去两次间隔10年的加拿大地盾湖泊调查中,我们确定了一些沿岸小型甲壳动物的酸性指示种。我们总共发现了90种其丰度在非酸性湖中比在酸性湖中高出几倍的枝角目动物和桡足亚纲动物。在这两次调查中非酸性湖泊的动物群有所变化。1987年的调查中使用了活动捕集器,比在后来的,拉网式的调查中捕到的沿岸生物种类多。这两次调查中均在酸性湖泊中发现了类似的动物群,并找到了几个很好的指示种。例如,Acanthocycops vernalis只存在于PH值小于6的湖泊中。Sinobosmina sp.是常见物种,但只存在于pH值大于4.8的湖泊中。Tropocyclops extensus(近剑水蚤属)、Mesocyclops edax和Sidacrystallina(晶莹仙达蚤)比较常见,但只存在于pH值大于5的湖泊中;而Chydorus faviformis(盘肠蚤属)只存在于pH值大于5.9的湖泊中。在两次调查活动中均接受调查的3个湖泊中,这些酸性指示种在从酸化中复原的早期阶段进行的测定中显示出较好的前景。
We identify littoral microcrustacean indicators of acidification in 2 surveys of Canadian Shield lakes conducted 10 years apart. We found a total of 90 cladoceran and copepod species with richness increasing severalfold from acidic to nonacidic lakes. The fauna of the nonacidic lakes differed between the surveys. The 1987 survey employed activity traps, and caught more littoral taxa than the more recent, net-haul-based survey. Similar faunas were identified in the acidified lakes in both surveys, and several good indicator species were identified. For example, Acanthocycops vemalis was restricted to lakes with pH < 6. Sinobosmina sp. was very common but only in lakes with pH > 4.8. Tropocyclops extensus, Mesocyclops edax, and Sida crystallina were commonly found but only at pH > 5, and Chydorus faviformis only at pH > 5.9. These indicators showed promise in gauging the early stages of recovery from acidification in 3 lakes that were included in both surveys.
