中文摘要：

在海岸前沿选取林地、草地、裸地3种不同的下垫面环境,研究风沙运动对其粒度的影响。结果表明,3个样地均以细沙为主,中沙、粗沙分列其后,但样地间沙粒含量差异很大;3个样地粒径均随海岸距离的增加而变粗,林地变化较为明显且粒径最粗,林地和草地下层的沙粒径都比表层的粗,裸地则无明显变化;与草地和裸地相比,林地内沙土平均粒径最粗,标准偏差最大,负偏程度最高,这与林地内粒径较粗有关;在草地和裸地中,平均粒径与各粒度参数均存在良好的相关性,表明草地和裸地沉积物为风力搬运堆积的产物,受风选作用明显。细沙与极粗沙和粗沙都呈现极显著的正相关关系,可以根据极粗沙和粗沙的含量来判别防护林的防护效应,即在海岸前沿,沙粒粒径越粗,防护效能越好。

英文摘要：

Three different underlying surfaces,the Casuarina Equisetifolia protection forest,the grassland and the bare land over coastal front zone were sampled to investigate the impact of sand drift movement on the grain size characteristics,results showed as follows. The surface sand samples in this region were dominated by fine sand,while medium sand and coarse sand exhibited decreasingly,but sand contents were significantly different between sample plots. Because of the degree of accumulation of sand,the grain size became bigger with the distance increasing,the protection forest had the most obvious change and the coarser grain size,the grain size of sub-surface（ below 100 mm） was coarser than that of the surface in the protection forest land and the grassland,but not in the bare land. Due to the coarser grain size,the protection forest land had the highest average particle size,largest standard deviation and the highest degree of negative bias compared with the grassland and bare land. Because of the pneumatic separation,there was remarkable correlation between average particle size and other particle size parameters in grassland and bare land,the coarse sand and very coarse sand showed very significant positive correlation with the silty sand so that we could use the content of the coarser sand to distinguish the protection effect of the protection forest,it meant that the coarser sand in the coastal front zone,the better protection effect it had.