Zhang Qian, Zhou Wei, Liang Guoqing, Wang Xiubin, Sun Jingwen, He Ping, Li Lujiu
Ministry of Agriculture Key Laboratory of Plant Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, P.R. China.
Institute of Soil and Fertilizer, Anhui Academy of Agricultural Sciences, Hefei, P.R. China.
PLoS One. 2015 Apr 16;10(4):e0124096. doi: 10.1371/journal.pone.0124096. eCollection 2015.
This study aimed to evaluate the effects of chemical fertilizer (NPK), NPK with livestock manure (NPK+M), NPK with straw (NPK+S), and NPK with green manure (NPK+G) on soil enzyme activities and microbial characteristics of albic paddy soil, which is a typical soil with low productivity in China. The responses of extracellular enzyme activities and the microbial community diversity (determined by phospholipid fatty acid analysis [PLFA] and denaturing gradient gel electrophoresis [DGGE]) were measured. The results showed that NPK+M and NPK+S significantly increased rice yield, with NPK+M being approximately 24% greater than NPK. The NPK+M significantly increased soil organic carbon (SOC) and available phosphate (P) and enhanced phosphatase, β-cellobiosidase, L-leucine aminopeptidase and urease activities. The NPK+S significantly increased SOC and available potassium (K) and significantly enhanced N-acetyl-glucosamidase, β-xylosidase, urease, and phenol oxidase activities. The NPK+G significantly improved total nitrogen (N), ammonium N, available P, and N-acetyl-glucosamidase activity. The PLFA biomass was highest under NPK+S, followed by NPK+M and NPK+G treatments. Principal component analysis (PCA) of the PLFA indicated that soils with NPK+M and NPK+S contained higher proportions of unsaturated and cyclopropane fatty acids (biomarkers of fungi and gram-negative bacteria) and soil under NPK+G contained more straight chain saturated fatty acids (representing gram-positive bacteria). PCA of the DGGE patterns showed that organic amendments had a greater influence on fungal community. Cluster analysis of fungal DGGE patterns revealed that NPK+G was clearly separated. Meanwhile, the bacterial community of NPK+M treatment was the most distinct. RDA analysis revealed changes of microbial community composition mostly depended on β-xylosidase, β-cellobiosidase activities, total N and available K contents. The abundances of gram-negative bacterial and fungal PLFAs probably effective in improving fertility of low-yield albic paddy soil because of their significant influence on DGGE profile.
本研究旨在评估化肥（氮磷钾）、氮磷钾配施畜禽粪便（NPK+M）、氮磷钾配施秸秆（NPK+S）以及氮磷钾配施绿肥（NPK+G）对白浆水稻土土壤酶活性和微生物特性的影响，白浆水稻土是中国典型的低产土壤。测定了胞外酶活性和微生物群落多样性（通过磷脂脂肪酸分析[PLFA]和变性梯度凝胶电泳[DGGE]测定）的响应。结果表明，NPK+M和NPK+S显著提高了水稻产量，其中NPK+M比NPK高出约24%。NPK+M显著增加了土壤有机碳（SOC）和有效磷（P），并提高了磷酸酶、β-纤维二糖酶、L-亮氨酸氨肽酶和脲酶的活性。NPK+S显著增加了SOC和有效钾（K），并显著提高了N-乙酰葡糖胺酶、β-木糖苷酶、脲酶和酚氧化酶的活性。NPK+G显著提高了全氮（N）、铵态氮、有效磷和N-乙酰葡糖胺酶的活性。PLFA生物量在NPK+S处理下最高，其次是NPK+M和NPK+G处理。PLFA的主成分分析（PCA）表明，NPK+M和NPK+S处理的土壤中不饱和脂肪酸和环丙烷脂肪酸（真菌和革兰氏阴性菌的生物标志物）比例较高，NPK+G处理的土壤中直链饱和脂肪酸（代表革兰氏阳性菌）含量较多。DGGE图谱的PCA表明，有机改良剂对真菌群落的影响更大。真菌DGGE图谱的聚类分析表明，NPK+G明显分离。同时，NPK+M处理的细菌群落最为独特。冗余分析（RDA）表明，微生物群落组成的变化主要取决于β-木糖苷酶、β-纤维二糖酶活性、全氮和有效钾含量。革兰氏阴性菌和真菌PLFAs的丰度可能对提高低产白浆水稻土的肥力有效，因为它们对DGGE图谱有显著影响。
