Answer:
Acid
Explanation:
Dead of dying lakes can be caused due to acid deposition. Acid deposition often termed as acid rain is the precipitation of acidic components like sulfuric or nitric acid in wet or dry form.
As the components in the deposition are acidic, when they come in contact with a lake, the acid content dissolves in the water and now the water of that lake become more acidic than normal. This causes a change in pH of the water in lake. As living organisms are sensitive to adverse pH changes, the acidic pH causes destruction of lives in the lake.
Plants are also living organism so they have also a range of pH optimum for their survival. Due to the acid rain the leaves for the plants get damaged and also the water that they absorb becomes acidic than normal so their normal physiology is affected.
