Background With the increasing cost of urban water resource, how to develop a water-saving planting mode in urban greenland and transform water consuming mode into water saving mode have become an academic hotspot which needs to be urgently solved for urban greenland management in semi-humid region.

Methods Using an artificial simulated rainfall system, we selected Chengyang district of Qingdao as an experimental area, determined the canopy interception of 6 shrub species including Ligustrum×vicaryi, Euonymus japonicus, Buxus sinica var. parvifolia, Photinia×fraseri, Juniperus chinensis and Platycladus orientalis, and analyzed the relationships between morphological characteristics and canopy interception.

Results Among 6 shrub species, the leaf area, leaf width and leaf length/width ratio of J. chinensis and P. orientalis were remarkably different with the other 4 shrub species and the LAIs of J. chinensis and P. orientalis were significantly higher than those of the other 4 shrub species (P < 0.05). For all the 6 shrub species, the descending order was throughfall rates > interception rates > stemflow rates, and throughfall and stemflow increased significantly, while the canopy interception decreased with the increase of rainfall intensity. Throughfall rates of broad-leaved shrubs were higher than that of coniferous shrubs (P < 0.05), and the changing trend of stemflow rates was similar (P < 0.05). However, the canopy interception rates showed an opposite pattern (P < 0.05). LAI, leaf width, leaf length/width ratio and contact angle were significantly correlated with canopy interception (P < 0.05), and LAI, phylliform and leaf wettability were the most important factors affecting canopy interception of shrubs.

Conclusions The broad-leaved shrubs tend to form a "funnel-shaped" stemflow water accumulation system, which contributed to the storage of soil water, while the coniferous shrubs favor canopy interception due to higher LAI, special leaf shape and high wettability of leaf surface, and had a stronger ability to regulate the storm flood before the canopy is water-saturated.