Climate-induced changes in the dissolved organic carbon budgets of boreal lakes
- Cite this article as:
- Schindler, D.W., Curtis, P.J., Bayley, S.E. et al. Biogeochemistry (1997) 36: 9. doi:10.1023/A:1005792014547
During 20 years of climatic warming, drought and increased forest firesbetween 1970 and 1990, DOC concentrations declined by 15--25%in lakesof the Experimental Lakes Area, northwestern Ontario, allowing increasedpenetration of both UV and photosynthetically-active radiation (PAR), andcausing deeper euphotic zones and thermoclines. Decreased input to thelakes of DOC from terrestrial catchments and upstream lakes was theprimary reason for the decline, although in-lake removal also increasedslightly. Decreased streamflow caused by drought was more important thanforest fires in affecting DOC exports from catchments. Experimentalacidification of lakes caused even greater losses in DOC, by enhancing ratesof in-lake removal. DOC in Lake 302S, acidified to pH 4.5 during the1980’s, declined to less than 10% of preacidificationvalues.