Biodiversity Variations of Soil Macrofauna Communities in Forests in a Reclaimed Coast with Different Diked History

A long history of reclamation has affected the coast of east China. This factor has been recognized as the most important cause of coastal wetland loss in the country. In August 2012, we selected six forest patches, each with ages after diking ranging between 30 and 200 years, occupied by planted poplar and metasequoia in the reclaimed coast at Yancheng city. We assessed the biodiversity and the taxonomic composition variation of soil macrofauna communities among these habitats. Hymenoptera, Isopoda, Haplotaxida, and Lepidoptera groups constituted 57.13% of the total macrofauna from the six habitats. The higher biodiversity values, expressed as Margalef's richness index (R) and Shannon-Weaver diversity (H'), were observed in the forests with a longer diked history, whereas lower values occurred in the forests in recently-reclaimed coasts. Ordination analysis (non-metric multi-dimensional scaling) demonstrated that soil macrofauna community parameters are determined by the diked age of the plots. One-way ANOSIM analysis showed significant differences between soil macrofauna community characteristics of the sample forest patches (P<0.050), with the exception of poplar forest compared to metasequoia forest diked approximately 30 years ago (P=0.558). The findings indicated that the biodiversity of soil macrofauna was significantly affected by the diked history, and the soil macrofauna distribution pattern was strongly related with soil development after reclamation.