State Key Laboratory Base of Eco-hydraulic Engineering in Arid Area, Xi'an University of Technology, Xi'an, 710048, China.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, 712100, China.
Sci Rep. 2017 Jul 26;7(1):6527. doi: 10.1038/s41598-017-06994-3.
The influence of elevated CO and nitrogen (N) addition on soil microbial communities and the rhizospheric effects of Bothriochloa ischaemum were investigated. A pot-cultivation experiment was conducted in climate-controlled chambers under two levels of CO (400 and 800 μmol mol) and three levels of N addition (0, 2.5, and 5 g N m y). Soil samples (rhizospheric and bulk soil) were collected for the assessment of soil organic carbon (SOC), total N (TN), total phosphorus (TP), basal respiration (BR), and phospholipid fatty acids (PLFAs) 106 days after treatments were conducted. Elevated CO significantly increased total and fungal PLFAs in the rhizosphere when combined with N addition, and N addition significantly increased BR in the rhizosphere and total, bacterial, fungal, Gram-positive (G), and Gram-negative (G) PLFAs in both rhizospheric and bulk soil. BR and total, bacterial, G, and G/G PLFAs were significantly higher in rhizospheric than bulk soil, but neither elevated CO nor N addition affected the positive rhizospheric effects on bacterial, G, or G/G PLFAs. N addition had a greater effect on soil microbial communities than elevated CO, and elevated CO and N addition had minor contributions to the changes in the magnitude of the rhizospheric effects in B. ischaemum.
研究了升高的 CO 和氮（N）添加对土壤微生物群落的影响，以及芨芨草根际的影响。在气候控制室内进行了盆栽实验，设置了两个 CO 水平（400 和 800 μmol mol）和三个 N 添加水平（0、2.5 和 5 g N m y）。在处理后 106 天，收集土壤样品（根际和非根际土壤），用于评估土壤有机碳（SOC）、总氮（TN）、总磷（TP）、基础呼吸（BR）和磷脂脂肪酸（PLFAs）。当与 N 添加结合时，升高的 CO 显著增加了根际的总 PLFA 和真菌 PLFA，而 N 添加显著增加了根际和非根际土壤的 BR、总 PLFA、细菌 PLFA、革兰氏阳性菌（G）PLFA 和革兰氏阴性菌（G）PLFA。根际土壤的 BR 和总 PLFA、细菌 PLFA、G 菌 PLFA 和 G/G 菌 PLFA 均显著高于非根际土壤，但升高的 CO 或 N 添加均未影响对细菌、G 菌或 G/G 菌 PLFA 的根际正效应。与升高的 CO 相比，N 添加对土壤微生物群落的影响更大，而升高的 CO 和 N 添加对芨芨草根际效应幅度的变化贡献较小。
