Relationship Between Leaf Sulfur Content and Atmospheric Pollutant Sulfur Concentration of 4 Main Greening Tree Species in Xinxiang

The difference of sulfur content between leaf and foliar dust of Populus tomentosa, Platanus orientalis, Sophora japonica and Fraxinus bungeana and atmospheric sulfur concentration in different function areas of northern Henan Province were studied by multiple comparisons(LSD method). Fitting monadic mathematic model of leaf sulfur content and foliar dust sulfur content and atmospheric sulfur concentration, using multivariate regression analysis method to establish their relationships. Results showed that sulfur content in leaves and foliar dust of 4 greening trees were increased with the increasing of atmospheric sulfur concentration, the increasing extent order was Populus tomentosa, Sophora japonica, Platanus orientalis and Fraxinus bungeana. The determination coefficient(R²)of simple regression mathematical model about the sulfur content of blades and foliar dust in Populus tomentosa, Platanus orientalis, Sophora japonica and Fraxinus bungeana was 0.917, 0.951, 0.956 and 0.890, respectively. The determination coefficient (R²) of simple regression mathematical model of the blade sulfur content and atmospheric sulfur concentration in 4 greening trees was 0.950, 0.932, 0.909 and 0.887, respectively. Binary regression mathematical model of blades and foliar dust sulfur content and atmospheric sulfur concentration in 4 greening trees showed that the determination coefficient (R²) was 0.978, 0.960, 0.967 and 0.899, respectively. F-test of all mathematical models reached an extremely significant level. Therefore, plant leaves and foliar dust could be used to monitor atmospheric SO₂ pollution as effective biomarkers, and could provide a reference for regional environmental monitoring.