Changes in Soil Dissolved Organic Carbon Affect Reconstructed History and Projected Future Trends in Surface Water Acidification

摘要: Preindustrial (1850s) and future (2060) streamwater chemistry of an anthropogenically acidified small catchment was estimated using the MAGIC model for three different scenarios dissolved organic carbon (DOC) concentrations sources. The highest modeled pH = 5.7 1850s as well 2060 (pH = 4.4) simulated given assumption that DOC concentration constant at 1993 level. A scenario accounting increase inverse function ionic strength (IS) soilwater resulted in much lower preindustrial (pH = 4.9) recovery to (pH = 4.1) if stream riparian zone assumed be only source. If upland (where significant observed −5 −15 cm) also included, partly neutralized within soil higher pH = 5.3 pH = 4.2 were estimated. flux 2–4 times than potential production zone, implying this is unlikely sole Modeling based on changes are solely attributable appears likely underestimate pH.