Sun Bing-jie, Jia Shu-xia, Zhang Xiao-ping, Liang Ai-zhen, Chen Xue-wen, Zhang Shi-xiu, Liu Si-yi, Chen Sheng-long
Ying Yong Sheng Tai Xue Bao. 2015 Jan;26(1):101-7.
A study was conducted on a long-term (13 years) tillage and rotation experiment on black soil in northeast China to determine the effects of tillage, time and soil depth on soil microbial biomass carbon (MBC). Tillage systems included no tillage (NT), ridge tillage (RT) and mould-board plough (MP). Soil sampling was done at 0-5, 5-10 and 10-20 cm depths in June, August and September, 2013, and April, 2014 in the corn phase of corn-soybean rotation plots. MBC content was measured by the chloroform fumigation extraction (CFE) method. The results showed that the MBC content varied with sampling time and soil depth. Soil MBC content was the lowest in April for all three tillage systems, and was highest in June for MP, and highest in August for NT and RT. At each sampling time, tillage system had a significant effect on soil MBC content only in the top 0-5 cm layer. The MBC content showed obvious stratification under NT and RT with a higher MBC content in the top 0-5 cm layer than under MP. The stratification ratios under NT and RT were greatest in September when they were respectively 67.8% and 95.5% greater than under MP. Our results showed that soil MBC contents were greatly affected by the time and soil depth, and were more apparently accumulated in the top layer under NT and RT.
在中国东北黑土区进行了一项为期13年的耕作与轮作长期试验，以确定耕作方式、时间和土壤深度对土壤微生物量碳（MBC）的影响。耕作系统包括免耕（NT）、垄作（RT）和铧式犁翻耕（MP）。在玉米-大豆轮作地块的玉米生长阶段，于2013年6月、8月、9月以及2014年4月，在0-5厘米、5-10厘米和10-20厘米深度采集土壤样本。采用氯仿熏蒸提取（CFE）法测定MBC含量。结果表明，MBC含量随采样时间和土壤深度而变化。对于所有三种耕作系统，土壤MBC含量在4月最低，MP处理在6月最高，NT和RT处理在8月最高。在每个采样时间，耕作方式仅对表层0-5厘米土层的土壤MBC含量有显著影响。NT和RT处理下MBC含量呈现明显的分层现象，表层0-5厘米土层的MBC含量高于MP处理。NT和RT处理下的分层比率在9月最大，分别比MP处理高67.8%和95.5%。我们的结果表明，土壤MBC含量受时间和土壤深度的影响很大，并且在NT和RT处理下更明显地积累在表层。
