螃蟹扰动作用对滨海湿地水盐交换的影响

为探究生物扰动作用对滨海湿地物质交换的影响，以螃蟹为研究对象进行室内控制试验，模拟了潮汐条件下不同螃蟹密度时沉积物地貌变化和水盐运移情况。结果表明:螃蟹能够将大量地下沉积物搬运至地表，形成起伏多变的微地形，使沉积物表面积明显增大；螃蟹活动能促进地表水与地下水交换，加快浅层土壤的盐分运移过程；地表水与地下水交换量和盐分运移量均随螃蟹密度的增大而明显增大。生物扰动作用是造成沉积物地貌改变的重要因素，进而促进了滨海湿地的水盐交换。

Effects of crab disturbance on water and salt exchange in coastal wetlands

In order to explore the effects of bioturbation on material exchange in coastal wetlands, a controlled laboratory experiment that made crabs as research object was conducted to study the effects of different crab densities on sediment geomorphology changes and water and salt transport under simulated tidal conditions. The results showed that crabs carried a large number of deep sediments to the surface, forming a rugged microtopography, which resulted in a significant increase of sediment surface area. Crab activities not only effectively promoted the exchange of surface water and groundwater but also accelerated salt migration process of shallow soil. The amount of surface water and groundwater exchange and salt transport increased significantly with the density of crabs. Therefore, it could be concluded that bioturbation is an important factor affecting sediment geomorphology, which greatly accelerates water and salt exchange in coastal wetlands.