Analysis on Impact of PLA Barrier on Soil Particle sizes of Sand Dunes

Biodegradable PLA fiber is a new type of fixing material.The tubular shapes of sandbags made of PLA are filling with sands,and are piled up on the sand dunes,which can effectively change the near-surface wind flow structure and roughness.Based on the impact to surface wind speed,PLA sandbag barriers can also impact the redistribution of soil particle sizes on the surface dunes.Through the measure of soil particle sizes in 0—11cm in different specification sand barriers,this article discussed the impact of different specifications and different slope positions to soil particle sizes.The results showed that:specifications(2m×2m)of laid sand barrier has the greater impact on soil particle size,and soil particle sizes on average are 16%bigger than that of sand dunes without laid sand barriers.Instead,specification(1m×1m)showed minimum impact.Soil particle size in the same specification showed the most obvious change on the top position.They are 21%bigger than those of sand dunes without laid sand barriers.The soil particle sizes on windward slope of the leeward slope were 3.9%and 2.4%larger compared to the control;soil particle size changes with the different soil depth.Soil particle size of 0—1cm depth changes most obviously,which is 16% bigger than that of sand dunes without sand barriers.Therefore,It can be seen that the sand particle size of dunes surface increases after the laying of sand barrier.