长期施肥对我国北方潮土碳储量的影响

Effects of Long-term Application Fertilizer on Carbon Storage in Calcareous Meadow Soil

利用20a长期肥料定位试验,研究了化肥单施与化肥、有机肥配施条件下土壤有机、无机碳在0～1m土层的分布特征,并在此基础上计算0～1m土层碳库的储量变化。结果表明,N、P肥的施用对土壤有机碳的累积表现为正效应,这一效应在耕层最为明显,耕层土壤无机碳含量随有机碳含量升高而降低。0～1m土层碳储量计算结果为:以常规水平单施氮、磷肥,有机碳储量较试验开始时增加14.4t·hm-2;有机肥与常规水平氮、磷肥配施,有机碳储量增加19.5t·hm-2;常规水平单施氮、磷肥处理与不施肥处理0～1m土层碳的总储量无差异,分别为146.8、146.9t·hm-2。

Changes of SOC and SIC pool in 0-1 m layer of calcareous meadow soil were studied in a long-term fertilizer location experiment that had been conducted for 20 years in North China Plain. The amount of SOC increased when applying N and P fertilizer, especially in the plowed layer, while the content of SIC decreased with the increasing of SOC content in the plowed layer. The amount of SOC in 0-1 m soil layer increased from 74.7 t·hm^-2 to 89.1 t·hm^-2 under normal application rates of N and P chemical fertilizers used by local farmers; while, when the chemical fertilizers were applied with manure, the amount of SOC increased to 94.2 t·hm^-2. There existed no significant difference in the total amount of carbon stored in 0-1 m soil layer between the treatment of normal application rates of N, P chemical fertilizer and the treat- ment of no fertilizer application, being 146.8 t·hm^-2 and 146.9 t·hm^-2 respectively.