Comparison of soil fungal/bacterial ratios in a pH gradient using physiological and PLFA-based techniques
Comparison of soil fungal/bacterial ratios in a pH gradient using physiological and PLFA-based techniques
复制标题
DOI：
10.1016/s0038-0717(03)00154-8
复制
发表时间：
2003-07-01
影响因子：
9.7
通讯作者：
Anderson, TH
中科院分区：
文献类型：
--
作者：
Bååth, E;Anderson, TH
我们比较了由 53 个成熟阔叶林土壤组成的 pH 梯度 (3.0-7.2) 中使用底物诱导呼吸 (SIR) 结合选择性抑制技术并使用磷脂脂肪酸 (PLFA) 技术估算的微生物总生物量和真菌/细菌比率。使用 PLFA 技术计算真菌/细菌生物量指数，使用 PLFA 18:2w6,9 作为真菌生物量的指标，并使用 13 种细菌特异性 PLFA 的总和作为细菌生物量的指标。使用 SIR 估算的微生物总生物量与总 PLFA (totPLFA) 之间存在良好的线性相关性 (p < 0.001)，表明 1 mg 生物量-C 相当于 130 nmol totPLFA。两种生物量估计值均与土壤 pH 值呈正相关。使用选择性抑制技术测量的真菌/细菌比率随着pH值从pH 3时的约9增加到pH 7时的约2而显着下降，而使用PLFA测量的真菌/细菌生物量指数往往随着土壤pH值的增加而略有增加。土壤麦角甾醇含量和 PLFA 18:2w6,9 之间的良好相关性表明，两种方法在估计真菌/细菌比率方面缺乏一致性并不是由于 PLFA 18:2w6,9 相关的非真菌结构有任何显着程度。几种 PLFA 与土壤 pH 值密切相关（R-2 值 > 0.8）；例如，PLFA 16:1w5 和 16:1w7c 随着土壤 pH 值的增加而增加，而 i16:0 和 cy19:0 则减少。总 PLFA 模式的主成分分析给出了与土壤 pH 值密切相关的第一个成分（R-2 = 0.85，p < 0.001），表明这些山毛榉/山毛榉橡树林土壤中的微生物群落组成在很大程度上由土壤 pH 值决定。 (C) 2003 Elsevier Science Ltd. 保留所有权利。
We have compared the total microbial biomass and the fungal/bacterial ratio estimated using substrate-induced respiration (SIR) in combination with the selective inhibition technique and using the phospholipid fatty acid (PLFA) technique in a pH gradient (3.0-7.2) consisting of 53 mature broad-leaved forest soils. A fungal/bacterial biomass index using the PLFA technique was calculated using the PLFA 18:2w6,9 as an indicator of fungal biomass and the sum of 13 bacterial specific PLFAs as indicator of the bacterial biomass. Good linear correlation (p < 0.001) was found between the total microbial biomass estimated with SIR and total PLFAs (totPLFA), indicating that 1 mg biomass-C was equivalent to 130 nmol totPLFA. Both biomass estimates were positively correlated to soil pH. The fungal/bacterial ratio measured using the selective inhibition technique decreased significantly with increasing pH from about 9 at pH 3 to approximately 2 at pH 7, while the fungal/bacterial biomass index using PLFA measurements tended to increase slightly with increasing soil pH. Good correlation between the soil content of ergosterol and of the PLFA 18:2w6,9 indicated that the lack of congruency between the two methods in estimating fungal/bacterial ratios was not due to PLFA 18:2w6,9-related non-fungal structures to any significant degree. Several PLFAs were strongly correlated to soil pH (R-2 values > 0.8); for example the PLFAs 16:1w5 and 16:1w7c increased with increasing soil pH, while i16:0 and cy19:0 decreased. A principal component analysis of the total PLFA pattern gave a first component that was strongly correlated to soil pH (R-2 = 0.85, p < 0.001) indicating that the microbial community composition in these beech/beech-oak forest soils was to a large extent determined by soil pH. (C) 2003 Elsevier Science Ltd. All rights reserved.