[Ecological functions of green land system in Harbin]

Patch and strip green lands in Harbin with plantation structure of tree + shrub + herb, tree + herb, shrub + herb, tree, shrub, and lawn were selected as studied objects. Through testing PAR, temperature (t), relative humidity (RH), and CO2 concentration in the center and outside of the selected green lands, the ecological functions of the green lands on regulating city microclimate were analyzed. The results showed that except lawn, patch green lands had the function of shading. Green lands with plantation structure of tree + shrub + herb, tree, tree + herb, and shrub had greater effects on lowering temperature, increasing humidity, and adjusting CO2 concentration than that of lawn. Strip green lands also had certain effects on shading, lowering temperature, increasing humidity, and adjusting CO2 concentration. Among different plantation structures of stripe green lands, shrub had the best effect on shading, and tree + shrub had the best effects on lowering temperature, increasing humidity, and adjusting CO2 concentration. The ecological functions of patch green lands were better than those of strip green lands with the same plantation structure, and green lands with multistoried structure had greater ecological effects than those with single layer.