Luo Da, Shi Zuo Min, Li Dong Sheng
Institute of Economic Forestry, Xinjiang Academy of Forestry Science, Urumqi 830063, China.
State Forestry Administration Key Laboratory on Forest Ecology and Environmental Sciences, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China.
Ying Yong Sheng Tai Xue Bao. 2018 Jul;29(7):2259-2268. doi: 10.13287/j.1001-9332.201807.031.
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 NH-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.
在中国南方亚热带地区,采用气压过程分离法(BaPS)和磷脂脂肪酸(PLFAs)谱分析法,研究了任豆人工林不同凋落物处理(对照、去除凋落物、双倍凋落物)下土壤碳(C)、氮(N)转化速率及微生物群落结构的季节变化。结果表明,不同凋落物处理下土壤呼吸速率和总硝化速率存在显著的季节变化,雨季速率显著高于旱季。在凋落物处理初期,土壤呼吸速率和总硝化速率随凋落物输入量增加而降低。随着凋落物处理时间延长,二者均随凋落物输入量增加而升高。不同凋落物处理下的微生物总PLFAs和各微生物类群PLFAs在旱季显著高于雨季。雨季真菌PLFAs/细菌PLFAs显著高于旱季。在旱季,去除凋落物显著增加了微生物总PLFAs、细菌PLFAs、真菌PLFAs和丛枝菌根真菌(AMF)PLFAs,分别增加了30.9%、28.8%、44.4%和31.6%。在雨季,去除凋落物显著降低了细菌PLFAs和AMF PLFAs,分别降低了10.6%和33.3%。土壤微生物群落结构受凋落物输入处理和季节的共同影响。土壤温度和NH-N是影响微生物群落结构的关键因素。任豆人工林的凋落物输入处理在短期内对土壤C、N转化速率和微生物群落结构有显著影响,且这种影响依赖于季节。