水热条件和施肥对黑土中微生物群落代谢特征的影响

EFFECT OF HYDROTHERMAL CONDITIONS AND FERTILIZATION ON METABOLIC CHARACTERISTICS OF MICROBIAL COMMUNITY IN A BLACK SOIL

选择位于我国东部3个不同气候带(温带、暖温带、中亚热带)的农业生态试验站(海伦站、封丘站、鹰潭站),设置水热变化梯度下的土壤置换试验,利用Biolog方法,研究了水热因子和施肥对单作玉米的黑土中微生物群落的影响。结果表明,在3种气候条件下,施用NPK肥均提高了黑土中细菌群落的碳源代谢活性(Average well color development,AWCD值表示)。在玉米抽雄期,施肥处理(NPK)黑土中AWCD值大小顺序为:鹰潭站(中亚热带)>海伦站(温带)>封丘站(暖温带),不施肥(CK)处理为:鹰潭站(中亚热带)>封丘站(暖温带)>海伦站(温带)。说明不施肥时黑土中微生物代谢活性随月均温度的提高而增加,而施肥和降水影响了温度对黑土中微生物代谢活性的作用。主成分分析表明,黑土中微生物群落代谢特征在海伦站(温带)和封丘站(暖温带)之间变化较小,而在鹰潭站(中亚热带)黑土中微生物群落的代谢指纹发生明显改变。气候条件变化导致的黑土中微生物代谢碳源的分异主要表现在:α-丁酮酸、腐胺、D,L-α-甘油、L-苏氨酸(r>0.9);而施肥导致的黑土中微生物代谢碳源的分异主要表现为:β-甲基-D-葡萄糖苷、葡萄糖-1-磷酸盐和丙酮酸甲脂。总体上,不同气候带水热条件的变化和施肥均影响了黑土中微生物群落的代谢活性和代谢特征的变化。

To study impact of climate and fertilization on soil microbial community, a transplant experiment of black soil （Phaeozem） was conducted at Hailun, Fengqiu and Yingtan Experiment Stations located separately in the temperate, warm temperate and mid-subtropical zone in East China. Soil microbial communities were measured by Biolog ECOPlate^TM. In different climate conditions, balance application of N, P and K increased soil microbial metabolic activity （ expressed as AWCD, average well color development）in black soils. In the teaseling stage of maize, AWCD of black soil followed a sequence of Yingtan station 〉 Hailun station 〉 Fengqiu station with fertilization （NPK） , and in a sequence of： Yingtan station 〉 Fengqin station 〉 Hailun station without fertilization （ CK）. The soil bacterial metabolic activity increased with the monthly mean temperature without fertilization, while the interaction of rainfall and fertilization increased soil bacterial metabolic activity and affected the impact of temperature. Principal component analysis of soil microbial communities showed that the metabolic fingerprint of soil microbial communities varied slightly between black soils in Hailun station and Fengqiu station, but significantly from that in Yingtan station under mid-subtropical monsoon climate. The effect of climate on variation of the carbon source of soil microbial communities was displayed in α-Ketobutyric Acid, Putrescine, D, L-α-Glycerol and L-Threonine （ R 〉 0.9） , while the effect of fertilization was in β-Methyl-D-Glucoside, Glucose-1- Phosphate and Pyruvic Acid Methyl Ester. To sum up, variation of the hydrothermal conditions in different climate zones and fertilization affects integrally metabolic activity and metabolic fingerprint of microbial communities in black soil.