UFZ - Helmholtz Centre for Environmental Research, Department of Soil Ecology, Theodor-Lieser-Str. 4, D-06120 Halle, Germany.
UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Microbiology, Permoserstr. 15, D-04318 Leipzig, Germany.
Sci Total Environ. 2017 Mar 1;581-582:756-765. doi: 10.1016/j.scitotenv.2017.01.005. Epub 2017 Jan 9.
We examined the impact of arbuscular mycorrhizal fungi and rhizobia on the living microbial community and microbial necromass under different long-term fertilization treatments at the long-term Static Fertilization Experiment Bad Lauchstädt (Germany). Phospholipid fatty acids (PLFA) and amino sugars plus muramic acid, were used as biomarkers for soil microbial bio- and necromass, respectively, and analyzed from six treatments imposed on two crop rotations, varying only in the inclusion/non-inclusion of a legume. Treatments included: two levels of only farmyard manure (FYM), only mineral fertilizer (NPK), the combined application of both fertilizer types and a non-fertilized control. PLFA profiles differed clearly between the investigated crop rotations and were significantly related to labile C, mineral N, and soil pH. This emphasizes the role of carbon, and of mycorrhizal and rhizobial symbioses, as driver for changes in the microbial community composition due to effects on the living conditions in soil. We found some evidence that legume associated symbiosis with arbuscular mycorrhizal fungi and rhizobia act as a buffer, reducing the impact of varying inputs of mineral nutrients on the decomposer community. While our results support former findings that living microbial populations vary within short-term periods and are reflective of a given crop grown in a given year, soil necromass composition indicates longer term changes across the two crop rotation types, mainly shaped by fertilizer related effects on the community composition and C turnover. However, there was some evidence that specifically the presence of a legume, affects the soil necromass composition not only over the whole crop rotation but even in the short-term.
我们研究了丛枝菌根真菌和根瘤菌对长期静态施肥实验（德国巴特劳施塔特）不同长期施肥处理下生活微生物群落和微生物残体的影响。磷脂脂肪酸（PLFA）和氨基糖加 muramic 酸分别作为土壤微生物生物量和微生物残体的生物标志物进行分析，来自两个作物轮作的六种处理，仅在包括/不包括豆科植物方面有所不同。处理包括：两种水平的仅厩肥（FYM）、仅矿物肥（NPK）、两种肥料类型的组合应用和未施肥对照。PLFA 谱在研究的作物轮作之间差异明显，并与可利用 C、矿物 N 和土壤 pH 显著相关。这强调了碳以及菌根和根瘤共生的作用，作为由于对土壤中生活条件的影响而导致微生物群落组成变化的驱动因素。我们发现一些证据表明，豆科植物与丛枝菌根真菌和根瘤菌的共生作用作为缓冲剂，减少了矿物养分输入变化对分解者群落的影响。虽然我们的结果支持了以前的发现，即生活微生物种群在短期内变化，并反映了特定年份种植的特定作物，但土壤残体组成表明两种作物轮作类型存在较长时间的变化，主要受肥料对群落组成和 C 周转的影响。然而，有一些证据表明，特别是豆科植物的存在，不仅会影响整个作物轮作的土壤残体组成，甚至会影响短期的土壤残体组成。
