|Veith, Tameria - Tamie|
|LU, HAIMING - Nanjing Research Institute For Agriculture|
|COLLICK, AMY - University Of Maryland Eastern Shore (UMES)|
Submitted to: Agricultural and Environmental Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/27/2016
Publication Date: 11/10/2016
Citation: Elkin, K.R., Veith, T.L., Lu, H., Goslee, S.C., Buda, A.R., Collick, A.S., Folmar, G.J., Kleinman, P.J., Bryant, R.B. 2016. Declining atmospheric sulfate deposition in a small agricultural watershed in central Pennsylvania, USA. Agricultural and Environmental Letters. 1:160039. doi:10.2134/ael2016.09.0039.
Interpretive Summary: Sulfur emissions from power production in the 70s and 80s were the leading cause of watershed impairment due to acidification. Since the introduction of the Clean Air Act, there has been about an 80% reduction in sulfur emissions resulting in the recovery of natural and aquatic environments and has been largely viewed as a success. Recently however, there has been a report suggesting that the decline in atmospheric sulfur deposition over the last few decades has also impacted agricultural systems. Furthermore, because sulfur is an essential element for crop production, this has the potential to negatively effect crop yields. Analyses of long-term trends in our own watershed support this idea and suggest that other long-term study watersheds may also be able to show similar findings.
Technical Abstract: Sulfur emissions in the northeastern USA are only 20% of what they once were due the enactment of the Clean Air Act. While there are numerous reports of aquatic and forested ecosystems recovering as a result of the decline in sulfur deposition, there is little information describing such effects in agricultural watersheds. We analyzed trends in water chemistry, streamflow, soil fertility and precipitation chemistry over a 32 year period in a small agricultural catchment in central Pennsylvania, USA. Both pH and sulfate-S concentration in precipitation and streamflow were highly correlated, pointing to watershed-scale impacts of Clean Air Act regulations. Many soils in the watershed were approaching crop nutrient deficiency for sulfur in recent years. These findings illustrate how long-term trends in water quality serve as the proverbial “canary in the coal mine,” elucidating emerging concerns that are not yet evident to upstream managers.