Summary: | Open and throughfall precipitation samples were collected at Haliburton Forest for a total of nine events from July – November of 2009. The following species were analyzed quantitatively: NO3-, SO42-, Cl-, HCOO-, C2O42-, NH4+, Na+, K+, Ca2+, and Mg2+. Wet deposition inputs to the system were quantified and the sources of wet-deposited species were probed. The throughfall method was employed to quantify inputs to the forest floor and probe canopy-precipitation interactions. Leaf wash samples at three heights aided in the interpretation of throughfall data and allowed for an examination of vertical profiles of dry deposition to the canopy. Results suggest possible nitrate foliar leaching during the growing season, although this appears to cease during senescence. This finding supports previous evidence that Haliburton Forest has shifted from nitrogen-limitation toward nitrogen-saturation and estimated total atmospheric N inputs to the system are close to the proposed critical load of 10 kg N ha-1 yr-1.
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