[Short-term effects of litter treatment on soil C and N transformation and microbial community structure in Erythrophleum fordii plantation]
- PMID: 30039664
- DOI: 10.13287/j.1001-9332.201807.031
[Short-term effects of litter treatment on soil C and N transformation and microbial community structure in Erythrophleum fordii plantation]
Abstract
In southern subtropical China, the seasonal variations of soil carbon (C) and nitrogen (N) transformation rates and microbial community structure under different litter treatments (control, litter removal, litter double) in Erythrophleum fordii plantation were studied by the methods of barometric process separation (BaPS) and phospholipid fatty acids (PLFAs) profiles. The results showed that there were significant seasonal variations in soil respiration and gross nitrification rates under different litter treatments, with significantly higher rates in the rainy season than in the dry season. In the initial stage of litter treatment, soil respiration and gross nitrification rates decreased with increasing litter inputs. With prolonged litter treatment, both of them increased with increasing litter inputs. The total microbial PLFAs and each microbial group PLFAs under different litter treatments were significantly higher in the dry season than those in the rainy season. The fungal PLFAs/bacterial PLFAs in the rainy season were significantly higher than that in the dry season. In the dry season, litter removal significantly increased the total microbial PLFAs, bacterial PLFAs, fungal PLFAs and arbuscular mycorrhizal fungal (AMF) PLFAs by 30.9%, 28.8%, 44.4% and 31.6%, respectively. In the rainy season, litter removal significantly decreased the bacterial PLFAs and AMF PLFAs by 10.6% and 33.3%, respectively. Soil microbial community structure was affected by both litter input treatments and seasons. Soil temperature and NH4+-N were the key determinants influencing the microbial community structure. The litter input treatments in E. fordii plantation had significant impacts on soil C and N transformation rate and microbial community structure in short-term, which were dependent on seasons.
以我国南亚热带格木人工纯林为研究对象,采用气压过程分离(BaPS)技术和磷脂脂肪酸(PLFAs)法研究了不同枯落物处理(对照、枯落物去除、枯落物加倍)下土壤碳氮转化速率和微生物群落结构的季节变化.结果表明:不同枯落物处理土壤呼吸和总硝化速率均呈现明显的季节动态,雨季显著高于旱季.枯落物处理初期,土壤呼吸和总硝化速率均随枯落物输入量的增加呈下降趋势,但随着枯落物处理时间的延长,二者随枯落物输入量的增加而增加.旱季不同枯落物处理土壤微生物PLFAs总量和各菌群PLFAs量均显著高于雨季,而雨季真菌PLFAs/细菌PLFAs明显高于旱季.在旱季,枯落物去除处理土壤微生物PLFAs总量、细菌PLFAs量、真菌PLFAs量和丛枝菌根真菌PLFAs量分别显著提高30.9%、28.8%、44.4%和31.6%.在雨季,枯落物去除处理细菌PLFAs量和丛枝菌根真菌PLFAs量分别显著降低10.6%和33.3%.土壤微生物群落结构受枯落物输入量处理和季节的双重影响,土壤微生物群落结构主要受土壤温度和铵态氮的影响.枯落物输入量处理在短期内显著影响了格木林土壤碳氮转化速率和微生物群落结构,这种影响因季节的不同而存在差异.
Keywords: Erythrophleum fordii plantation; litter; microbial community; phospholipid fatty acid; seasonal dynamics; soil C and N transformation.