Eisalou, HK; Sengonul, K; Gokbulak, F; Serengil, Y; Uygur, B
The objective of this study was to determine how the canopy
cover and forest floor of sessile oak, oriental beech, and Anatolian black pine stands affect the
rainwater chemical parameters. The chemical parameters investigated were pH, electrical
conductivity, total nitrogen (N), total phosphorus (P), sulfate (SO4)(2-), nitrate (NO3)(-),
ammonia (NH3)(+), permanganate index (PI), chloride (Cl-), sodium (Na+), potassium (K+), calcium
(Ca2+), magnesium (Mg2+), iron (Fe), aluminum (Al), and lead (Pb). Forest canopy covers
significantly affected pH, total N, total P, SO42-, Na+, and K+ contents in the throughfall,
while forest floors influenced all chemical properties, except for NH3+ and Pb in the forest
floor solution. While rainwater pH changed from medium acid (5.79) to strongly acid for both the
throughfall (5.48) and forest floor solution (5.50) in the pine stand, it increased to neutral
(6.57) in the oak and slightly acid (6.15) in the beech forest floor solution for the
throughfall. Regardless of forest stand types, mean total P values of rainwater significantly
decreased after passing through the canopy, but a change was not detected in the forest floor
solution. A significant amount of SO42- was retained in the forest floor. Average SO42- values
decreased from 4.90 mg L-1 in the rainwater to 1.14-1.04 mg L-1 in the forest floor solution of
oak, beech and pine stands. Forest floor under the beech stand had significantly higher nitrate
leaching than that under other two stands. Canopy covers of oak, beech and pine stands did not
significantly influence the concentrations of Ca2+, Mg2+, Fe, and Al in the throughfalls.
However, the same chemical parameters significantly increased in the forest floor. Given that the
forest canopy cover and floor of all three stands had significantly different effect on rainwater
chemistry, various tree species appear to differently influence the stream water chemistry.
Therefore, selection of tree species for afforestation projects in fresh water producing
watersheds becomes important to maintain water quality in streams for aquatic life and fresh
water consumers. (C) 2012 Elsevier B.V. All rights reserved.