Recovery from acid deposition is responsible for changing both the concentration and chemistry of dissolved organic carbon in Northeastern lakes, according to a new study published in Environmental Science and Technology.
Acid deposition, which includes acid rain, reduced the pH of lakes in many regions of North America until legislation began curtailing pollution in the early 1990s. At the peak of acidification, many lakes had lower DOC levels than they do today because it becomes insoluble at low pH levels. Today, lakes are recovering and DOC levels are rebounding as this terrestrially derived DOC moves back into solution. The implications include reduced light penetration and warmer surface waters.