Transformation of Straw 14 C in Ultisol and Vertisol *1  

Transformation of Straw ^(14)Cin Ultisol and Vertisol

作　　者：WANGZHIMING HUANGDONGMAI 等 

机构地区：[1]InstituteofSoilanFertilizer,JiangsuAcademyofAgriculaturalSciences,Nanjing210014（China） [2]InstituteofSoi

出　　处：《Pedosphere》1998年第2期181-186,共6页土壤圈（英文版）

摘　　要：Laboratory incubation was conducted to investigate transformation of straw 14 C in Ultisol and Vertisol under aerobic condition for 112 d at 30 oC. Dried and ground 14 C labeled rice and maize straws were mixed with the soils at the rate of 2.5 g kg -1 . Decomposition of the straw C and native soil C both revealed two stages, being faster during the initial days, and slower thereafter. About 37.33%～48.80% of the straw C and 4.22%～6.83% of the native soil C decomposed by the end of the incubation. The kinds of the straws only slightly influenced the rates of their decomposition in soils, however, some retardation was found in Ultisol at the initial decomposition stage due to its lower pH. Positive priming effects were observed in the soils applied with straw, and the rate of priming effect ranged from 7.23% to 13.80%. Net losses of native soil C were found under such incubation conditions, except Ultisol with rice straw. Soil biomass C and 14 C decreased gradually with incubation time, and seemed to be consistent with the decomposition patterns of straw C and native soil C. The ratio of biomass 12 C to biomass 14 C ranged from 1.35 to 3.37. Soil biomass C occupied 1.17%～2.32% of the total soil organic C, and the proportion of biomass 14 C to the residual 14 C varied from 7.3% to 14.3%.ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｔｒａｄｉｔｉｏｎａｌｍａｎｎｅｒｏｆｔｒａｃｉｎｇｔｈｅｄｅｃｏｍｐｏｓｉｔｉｏｎｏｆｐｌａｎｔｒｅｓｉｄｕｅｓｉｎｓｏｉｌｈａｓｓｅｒｉｏｕｓｌｉｍｉｔａｔｉｏｎｓ（Ｓｔｅｖｅｎｓｏｎ，１９８５）．Ｔｈｅｕｓｅｏｆｓ...

关 键 词：carbon transformation soil microbial biomass straw         14  C 

分 类 号：S153[农业科学—土壤学]