Which food chain includes organisms that would most immediately be affected by acid rain?

The organisms that would most immediately be affected by acid rain would be phytoplankton in lakes. What would then occur would be diminished insect populations which use phytoplankton as a food source, and then to larger animals like frogs and other insect eating animals. As the interdependence of the food web relies on all these organisms to be in balance, the imbalance that is created by the introduction of acid rain into any part of the food chain will have effects on the entire food web.