an increasing trendp < 0.001
lasiocarpa showed parabolic form, but basically showed an increasing trend with increasing water table depth in our data range (R 2 = 0.39, F = 31.972, p < 0.001), while C . angustifolia displayed a negative correlation between height and water table depth (R 2 = 0.05, F = 5.945, p < 0.02).