Study on sand transporting rate of different types of Poplar sand-fixation plantation in scattered sandy land of in Northern Hebei

In order to understand the effect of sand fixation plantation in scattered sandy land,there were eight different types of poplar stand were surveyed by the method of sample-plot,including three tree species of Populus simonii Carr.,Populus simonii×(Populus pyramidalis+Salix matsudana)cv.Poplaris,and Populus bolleana,Mmeanwhile,sand transporting rate was observed by 10-hole sand gathering machine.The results showed that sand-fixation plantations played an important role in blocking sand,reducing wind erosion.Different types of stands had different sand transporting rates,but 80%~90% of sand was shifted only under the height of 4cm above ground,and reducing along the height,the volume of transported sand was ranked as 0~2cm2~4cm 4~8cm 80~10cm.The study also discovered that sand transporting rate was influenced by both canopy density and average tree height in horizontal and vertical direction respectively,but it was not affected by stand type,canopy breadth and herb layer coverage.