Abstract:Reclamation is a very common disturbance to the alluvial lands of estuaries. In China, the reclaimed alluvial lands are generally used for agricultural or industrial purposes. However, the physical and chemical properties of these reclaimed lands had been rarely studied. Particle size distribution (PSD) has been proven to be a useful indicator of land use. In the present study, we tried to clarify the changes of PSD under different land use types and durations. East End of Chongming Island at the Yangtze Estuary, the largest alluvial island in the world, which has a chronosequence of reclaimed lands, provides a good and special case to study the changes of PSD after reclamation. Three long-term land use types, i.e. paddy field, vegetable field and woodland, were involved. Soil samples of different land use types and different durations were collected. The soil particle size distribution was determined by using a Beckman-Coulter LS 13320 laser particle size analyzer, and the particle size fractions were performed. The changes of particle size fractions (i.e., >63μm, 63-32μm, 32-16μm, 16-4μm, and <4μm representing sand-, coarse silt-, medium silt-, fine silt-, and clay-sized fractions, respectively) were analyzed. An order of magnitude was revealed in the terms of the soil mean particle size: tidal flat