Abstract:In order to understand the effects of the Dicranopteris pedata population with different coverage on soil carbon content and nutrient status of Phyllostachys edulis forest, the stability and ecological stoichiometric characteristics of soil aggregates in P. edulis forest under 7.75% (PE) and 63.25% (DD) coverage of D. dichoyoma in Changning County, Sichuan Province were studied. The results showed that the content of large aggregates in DD plot was significantly lower than that in PE plot, which caused the decrease of aggregate stability. Moreover, the contents of total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in DD plot were significantly lower than those in PE plot, and the decrease of TP was the largest, which made significant increase of soil C: N, C: P and N: P. There was no difference in the contents of TOC, TN, TP, C: N, C: P and N: P in litter leaves and fine roots of P. edulis between DD and PE plots, but the contents of TN and TP in litter leaves and fine roots of D. dichoyoma were significantly higher than those of P. edulis in DD plots. The correlation analysis showed that the TP content in fine roots of P. edulis and D. dichoyoma were significantly positively correlated with that in soil large marcroaggregate, microaggregate and small marcroaggregate. So the high coverage of D. dichoyoma in moso bamboo forest could decrease the stability of soil aggregates, and reduced the contents of TOC, TN and TP in soil, which could increase the absorption of N and P in soil aggregates with different size classes by changing the soil ecological stoichiometric characteristics, especially the absorption of P. It should be considered to adjust the coverage of D. dichoyoma in the extensive management of moso bamboo forest in southern Sichuan, in order to ensure the long-term sustainability of soil nutrient supply.
