Meander Lake in Minnesota is very sensitive to acid rain because it has low alkalinity. A model was used to see how the lake would react to different levels of acidic deposition. With the current rate of acid rain, the lake can keep its alkalinity and pH stable. If acid rain increases by 50%, the lake's alkalinity and pH will decrease over time. But if acid rain decreases by 50%, the lake's alkalinity and pH will increase. The lake is protected by minerals around it that help neutralize the acid rain. Some lakes in Minnesota might actually have more alkalinity than we thought because of organic acids.