Controversies in Science/Are humans causing global warming/a critique of Global warming and the export of dissolved organic carbon from boreal peatlands

(Review Paper) Cited in

Points Made
Additionally to changes in temperature, global warming also affects water - table levels and discharge from peatlands. Consequently, this affects the delivery of dissolved organic carbon (DOC) to downstream ecosystems where the productivity control is held along with biochemical cycles and reduction of visible and UV radiation. .

Methods
To measure the changes caused by climate change, mesocoms consisting of plastic insulated tanks were sunk in the ground. They were then exposed to infrared radiation which was set at ambient, half or full heat light and left during growing season.

Controlling water tables using water temperature as the manipulative variable we would see the responding variable measurements through the amount of discharge. The outcome is that the amount of dissolved organic carbon is controlled mainly by alterations in the discharge and is not as much by effects of warming and/or position. .

Results
The effects of the increase in temperature have influences on the regional carbon resources and the ecology of boreal and arctic surface waters. The results of the experiments were consistent with the decrease in DOC loadings into lakes in Ontario during warmer and drier than average years. This in turn increased UV penetration significantly thus causing lethal doses for many surface littoral organisms. These indirect effects of global warming may be the consequence of reductions in DOC export from peatlands under warmer climates.



ABOVE GRAPH: The water table levels are the effects due to infrared loading on bogs. From 1995-1997 the points on the graph represent infrared loading water table treatment combinations.

.