Soil aggregate stratification of nematodes and microbial communities affects the metabolic quotient in an acid soil
Soil aggregate stratification of nematodes and microbial communities affects the metabolic quotient in an acid soil
复制标题
线虫和微生物群落的土壤团聚体分层影响酸性土壤中的代谢商
DOI：
10.1016/j.soilbio.2013.01.006
复制
发表时间：
2013-05-01
影响因子：
9.7
通讯作者：
Wang, Feng
中科院分区：
文献类型：
--
作者：
Jiang, Yuji;Sun, Bo;Wang, Feng
已知添加新鲜有机物可以改变土壤团聚和土壤生物群落组成。我们假设施肥改变了土壤团聚体中土壤线虫和微生物群落的组成，线虫和微生物之间的相互作用可以刺激或抑制微生物活动。我们通过 9 年施肥的田间试验，研究了中国亚热带种植玉米的酸性土壤中线虫和微生物群落的团聚体尺寸变化。在四种施肥方案下，对土壤的三个聚集体尺寸部分的线虫、微生物群落和代谢商（qCO(2)）进行了检查。三个团聚体部分包括大团聚体 (>2000 μm; LA)、小团聚体 (250-2000 μm; SA) 以及团聚体间土壤和空间 (SA > IA)。IA 部分中线虫结构指数 (SI) 的高值表明食物网中存在着具有许多联系的复杂群落结构。团聚体部分也影响微生物生物量和多样性。PLFA 特征分析表明微生物生物量和多样性（香农指数）随着团聚体尺寸的减小而增加。然而，SA 部分的土壤代谢商（qCO(2)）显着高于 IA 部分，只有施肥对线虫群的组成有显着影响，而施肥和团聚体部分均显着影响微生物群落组成。施肥处理（分别为 44% 和 48%）和团聚体尺寸（分别为 6.0% 和聚集增强树 (ABT) 分析表明，总 C 对微生物生物量影响最大，而 pH 则影响线虫总数。食菌动物的丰度与施肥处理和聚集分数之间的细菌生物量呈显着正相关（r(2) = 0.17，P = 0.026），这可以部分解释线虫总数与 qCO(2) 之间的显着负相关。 = 0.25，P = 0.002）。微生物食草可能会降低微生物活性。(C) 2013 Elsevier Ltd. 保留所有权利。
The addition of fresh organic matter is known to modify both soil aggregation and soil biotic community composition. We hypothesized that fertilization alters the composition of soil nematode and microbial communities in soil aggregates, and the interaction between nematodes and microbes can stimulate or inhibit microbial activity. We used a field experiment with 9 years of manure application to investigate changes in nematodes and microbial communities among aggregate size fractions in an acid soil planted with maize in subtropical China. Nematodes, microbial communities, and metabolic quotient (qCO(2)) were examined within three aggregate size fractions from soils under four fertilization regimes. Three aggregate fractions include large macroaggregates (>2000 mu m; LA), small macroaggregates (250-2000 mu m; SA), and inter-aggregate soil and space ( SA > IA. A high value for the nematode structure index (SI) in the IA fraction suggested a complex community structure with many linkages in the food web. Aggregate fractions also influenced microbial biomass and diversity. PLFA signature analysis revealed that microbial biomass and diversity (Shannon index) increased with decreasing aggregate size. However, the SA fraction had a significantly higher soil metabolic quotient (qCO(2)) than the IA fraction. Only fertilization had a significant effect on the compositions of nematode groups, while both fertilization and aggregate fractions significantly affected microbial community composition. The variations in the composition of nematode and microbial communities could be explained independently by fertilization treatments (44% and 48%, respectively) and aggregate size (6.0% and 21%, respectively). Aggregated boosted trees (ABT) analysis indicated that total C exerted the strongest influence on microbial biomass, while pH influenced the total number of nematodes. The abundance of bacterivores showed a significant positive association with bacterial biomass across fertilization treatments and aggregate fractions (r(2) = 0.17, P = 0.026), which could partly explain the significant negative correlation between the total number of nematodes and qCO(2) (r(2) = 0.25, P = 0.002). The grazing on microbes by microbivores may decrease microbial activity. (C) 2013 Elsevier Ltd. All rights reserved.