帽儿山温带森林演替初期土壤碳、氮、磷计量特征的变化

Changes in stoichiometry of soil carbon,nitrogen and phosphorus in the early stage of temperate forest succession in Maoershan,Northeast China

2004年在帽儿山森林生态站设置土壤置换试验,将0~30 cm农田土置换成邻近天然次生林淋溶层土（A处理）、淀积层土（B处理）和母质层土（风化砂,C处理）,分别模拟森林皆伐次生演替、无种子库次生演替和原生演替,2014年研究温带落叶阔叶林不同演替类型在自然演替初期土壤碳、氮、磷计量特征的变化.结果表明：演替10年,A处理土壤碳、氮、磷含量无显著变化,B处理土壤碳和氮含量分别降低34.7%和38.6%,而C处理土壤碳和氮含量分别增加63.4%和198.4%.植被演替后,氮-碳异速生长关系斜率显著降低,磷-氮异速生长速率显著升高.10年演替后,仅C处理土壤C∶N减小44.5%,N∶P增加283.6%,其他处理变化不显著.土壤碳、氮、磷含量与活细根现存量、死细根现存量均存在显著相关关系,植被演替可能主要通过改变有机质输入驱动土壤碳、氮、磷含量及其计量关系.

A soil displacement experiment was established in the Maoershan Forest Ecosystem Research Station in 2004,replacing the cropland soil of the 0-30 cm depth with the eluvial horizon soil（A treatment）,the sediment horizon soil（B treatment） and the parent material horizon soil（weathered sand,C treatment） of an adjacent temperate broadleaved stand.The three treatments simulated the secondary successions from forest clear-cutting,bare soil without seed bank,and primary succession,respectively.Changes in soil carbon,nitrogen,phosphorus and their stoichiometry were examined in 2014.The results indicated that during the ten-year succession,the contents of soil C,N and P changed insignificantly in the A treatment.The contents of soil C and N decreased by 34.7% and 38.6% in the B treatment,but increased by 63.4% and 198.4% in the C treatment,respectively.The slope of the log-transformed N-C relationships decreased significantly during the succession,while the slope of the log-transformed P-N relationships increased significantly.After 10-year’s succession,only the C：N decreased by 44.5%,and the N：P increased by 283.6% in the C treatment,with no significant changes for others.The contents of C,N and P were significantly correlated with the root biomass and necromass,suggesting that the succession might change the soil elements and their stoichiometric relationships through modifying organic matter inputs.