水稻碳氮吸收、分配与积累对施肥的响应

Effect of Fertilization on the Absorption,Partition and Accumulation of Carbon and Nitrogen of Rice Under the Equal N Conditions

以亚热带典型稻田生态系统长期定位试验为对象,研究等氮条件下不同施肥方式对水稻植株碳氮吸收、分配与积累的影响,分析了水稻碳氮的积累关系.结果表明,低量有机肥结合化肥配施能有效促进碳素在水稻植株体内的分配.有机-无机肥配施处理下水稻茎叶和籽实中氮含量相对较高,分别为8.9～10.2 g.kg-1和11.9～14.8 g.kg-1,分别比单施化肥处理高13%～53%和9%～19%,比对照(不施肥)处理高12%～77%和23%～32%.水稻碳、氮储量大部分积累在植株的地上部分,其中,有机-无机肥配施处理下水稻籽实中碳、氮储量较大,分别为3467.8～4323.9 kg.hm-2和120.3～135.2 kg.hm-2,比单施化肥处理分别高13%～23%和26%～45%.研究表明,籽实是水稻植株主要的碳、氮汇,有机-无机肥料配施有利于水稻碳的积累和氮的吸收,其水稻碳氮的固定、吸收还具有一定的潜力.

In this study,the assimilation,partition and accumulation of carbon（C） and nitrogen（N）,as well as the relationship between C and N accumulation of rice,were studied from typical paddy ecosystems under long-term fertilizer applications with equal N inputs in subtropical China.The results showed that chemical fertilizer plus low organic manure（LOM） could promote effectively the distribution of C in the rice plant.The N content in the stem-leaf and grain of rice under organic-inorganic fertilization was 8.9-10.2 g·kg^-1 and 11.9-14.8 g·kg^-1 respectively.It was much higher than under other treatments,with about 13%-53% and 9%-19% higher than under the chemical fertilization（NPK）,separately and 12%-77% and 23%-32% higher than under the control treatment（CK）,respectively.The C and N storages of rice were mainly accumulated in the aboveground part.Organic-inorganic fertilization treatment possessed higher storages of C（3 467.8-4 323.9 kg·hm^-2） and N（120.3-135.2 kg·hm^-2） in the rice grain,which was about 13%-23% of C and 26%-45% of N higher than under NPK treatment.It indicated that rice grain was the main sink of C and N.The organic-inorganic fertilization was in favor of C accumulation and N absorption in the rice plant and it still possesses an obvious potential in C and N sequestration and absorption in subtropical paddy field.