首页|期刊导航|中国农业科学（英文版）|Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province, China
中国农业科学（英文版）2007，Vol.6Issue(4)：466-474,9.
Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province, China
Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province, China
摘要
Abstract
In order to understand the status of fixed ammonium, fixed ammonium content, maximum capacity of ammonium fixation, and their influencing factors in major types of tillage soils of Hunan Province, China, were studied with sampling on fields, and laboratory incubation and determination. The main results are summarized as follows: (1) Content of fixed ammonium in the tested soils varies greatly with soil use pattern and the nature of parent material. For the paddy soils, it ranges from 135.4 ± 57.4 to 412.8±32.4 mg kg-1, with 304.7±96.7 mg kg-1 in average; while it ranges from 59.4 to 435.7 mg kg-1, with 230.1 ± 89.2 mg kg1 in average for the upland soils. The soils developed from limnic material and slate had higher fixed ammonium content than the soils developed from granite. The percentage of fixed ammonium to total N in the upland soils is always higher than that in the paddy soils. It ranges from 6.1 ± 3.6% to 16.6 ±4.6%, with 14.0% ± 5.1% in average for the paddy soils and it amounted to 5.8 ±2.0% to 40.1 ± 17.8%, with 23.5 ± 14.2% in average for upland soils. (2) The maximum capacity of ammonium fixation has the same trend with the fixed ammonium content in the tested soils. For all the tested soils, the percentage of recently fixed ammonium to maximum capacity of ammonium fixation is always bellow 20% and it may be due to the fact that the soils have high fertility and high saturation of ammonium-fixing site. (3) The clay content and clay composition in the tested soils are the two important factors influe ncing their fixed ammonium content and maximum capacity of ammonium fixation. The results showed that hydrous mica is the main 2:1 type clay mineral in ＜0.02 mm clay of the paddy soils, and its content in 0.02-0.002 mm clay is much higher than that in ＜ 0.002 mm clay of the soils. The statistical analysis showed that both the fixed ammonium content and the maximum capacity of ammonium fixation of the paddy soils were positively correlated with the total 2:1 type clay mineral content and hydrous mica content in ＜ 0.02 mm clay and 0.02-0.002 mm clay at the significant level of P0.01 or P0.05, respectively, but not correlated with the total 2:1 type clay mineral content and hydrous mica content in ＜0.002 mm clay significantly. It demonstrated that the ammonium-fixing matrix of the tested soils mainly exists in the 0.02-0.002 mm clay. The above-mentioned results showed that fixed ammonium is a major form of N in the tillage soils in Hunan Province, China. It would play an important role in N nutrition of crops, especially for upland crops, and deserve to be further researched.关键词
Hunan Province/tillage soils/paddy soil/upland soil/fixed ammonium/maximum capacity of ammonium fixationKey words
Hunan Province/tillage soils/paddy soil/upland soil/fixed ammonium/maximum capacity of ammonium fixation分类
农业科技引用本文复制引用
ZHANG Yang-zhu,HUANG Shun-hong,WAN Da-juan,HUANG Yun-xiang,ZHOU Wei-jun,ZOU Ying-bin..Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province, China[J].中国农业科学（英文版）,2007,6(4):466-474,9.基金项目
This study was supported by National Key Technology R&D Program in the 10th Five-Year Plan of China (2004BA520A01). （2004BA520A01）
