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作 者 ：何念祖;倪吾钟

期 刊 ：植物营养与肥料学报 1996年 2卷 4期 页码：315-321

关键词：肥料管理；有机碳；稻田土壤；麦mdash；稻mdash；稻耕作制；

摘 要 ：采用田间长期定位试验,研究了不同施肥条件下浙江省三熟制高产稻田土壤有机碳的消长和平衡。结果表明,浙江省三熟制高产稻田耕层(0～20cm)土壤有机碳(C)的年自然矿化量在1800～2000kg/hm²;作物根茬有机碳量与子粒产量密切相关。两者的比值相当稳定,分别为0.30(单施化肥)和0.32(化肥有机肥配施),这便于估算耕层的根茬有机碳量。试验结果还表明,根茬有饥碳对维持耕层土壤有机碳的平衡有相当大的贡献,但在单施化肥时大多不足以补充矿化消牦;在不施肥时,根茬生物量和有机碳量均逐年下降。试验发现,可以利用土壤有机碳的年自然矿化量、矿化因数、子粒产量和(或)有机碳施入量来测算耕层土壤有机碳的消长和有机碳的平衡施用量。测算结果表明,浙江省三熟制高产稻田有机碳(C)的年平衡施用量一般不大于1600kg/hm²,折成水稻秸秆约为4000kg/hm²,相当于全年水稻秸杆总生物量的三分之一左右,可作为推荐有机肥用量之参考。

Abstract:With the long-term field experiments, the flutuaticm and balance of organic carbon (OC) in high-yield paddy soils with wheat-rice-rice cropping system in Zhejiang province were studied. It was found that the annual naturally-mineralized amounts of soil OC in plough horizon (0~20) were from 1800 to 2000kg/hm², and the amounts of OC in root and stubble were closely related to the grain yields with the ratio (amount of OC in root and stubble to grain yield) of 0. 30 (only mineral fertilizers applied] or 0.32 (intergrated supply with mineral fertilizers and organic manure as rice straw), which was suitable to estimating the amount of OC in root and stubble kept in plough horizon. The results indicated that OC in crop root and stubble was available for balance of soil OC in plough horizon, but was not enough generally as only mineral fertilizers were supplied. With no fertilizer, the biomass and the amount of OC of crop root and stubble both decreased year after year. It was also obtained that the balance of soil OC and the balanced rate of OC could be assessed with the annual amount of soil OC naturally-mineralized, mineralization facter, grain yield and (or) applied amount of OC. The balanced rate of OC is less than 1600kg/hm². as rice straw about 4000kg/hm², which is mostly one third of total biomass of rice straw producted in a year. It can be used as a reference for organic manuring.

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