Microbial community utilization of added carbon substrates in response to long-term carbon input manipulation
Microbial community utilization of added carbon substrates in response to long-term carbon input manipulation
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DOI：
10.1016/j.soilbio.2006.01.022
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发表时间：
2006-08-01
影响因子：
9.7
通讯作者：
Myrold, David D.
中科院分区：
文献类型：
--
作者：
Brant, Justin B.;Sulzman, Elizabeth W.;Myrold, David D.
植物输入土壤的化学成分和数量是控制土壤微生物群落大小和结构的主要因素。关于土壤微生物群落组成的变化如何影响分解速率和其他生态系统功能，人们知之甚少。本研究探讨了普遍的C-13标记的葡萄糖，谷氨酸，草酸盐，苯酚在土壤中的老增长花旗松（花旗松），西部铁杉（铁杉）森林在俄勒冈州瀑布，经历了7年的慢性C输入操作。在这个实验中使用的土壤是一个更大的碎屑输入和去除处理实验的一部分，并已收到正常的C输入（对照），加倍的木材输入，或根和凋落物输入排除（无输入）。加倍木材处理的土壤具有较高的真菌：细菌比，而无投入物处理的土壤具有较低的真菌：细菌比，比对照土壤。利用添加到现场操作的土壤中的化合物的差异进行了评估以下的C-13示踪到微生物生物量和呼吸。此外，C-13-磷脂脂肪酸（PLFA）分析用于检查添加的底物的差异微生物利用。葡萄糖和谷氨酸的代谢相似，在土壤中的所有三个凋落物处理。相比之下，在双木土壤中的微生物群落呼吸更多的添加苯酚和草酸，而在没有输入的土壤中的微生物呼吸更少的添加苯酚和草酸，比对照土壤。苯酚主要被纳入真菌PLFA，特别是在双木处理的土壤中。所有四种基质的添加导致增强降解的土壤有机质（启动）在土壤中的所有三个凋落物处理，和更大的苯酚和草酸盐相比，葡萄糖和谷氨酸。引发是更大的没有投入的土壤相比，控制或加倍的木材土壤。这些结果表明，改变植物对土壤的投入可能会导致微生物对碳化合物的利用发生变化。看来，许多这些变化是在微生物群落的大小和组成的改变的结果。(c)2006爱思唯尔有限公司保留所有权利。
The chemical composition and quantity of plant inputs to soil are primary factors controlling the size and structure of the soil microbial community. Little is known about how changes in the composition of the soil microbial community affect decomposition rates and other ecosystem functions. This study examined the degradation of universally C-13-labeled glucose, glutamate, oxalate, and phenol in soil from an old-growth Douglas-fir (Pseudotsuga menziesii)-western hemlock (Tsuga heterophylla) forest in the Oregon Cascades that has experienced 7 y of chronic C input manipulation. The soils used in this experiment were part of a larger Detritus Input and Removal Treatment experiment and have received normal C inputs (control), doubled wood inputs, or root and litter input exclusion (no inputs). Soil from the doubled wood treatment had a higher fungal: bacterial ratio, and soil from the no inputs treatment had a lower fungal: bacterial ratio, than the control soil. Differences in the utilization of the compounds added to the field-manipulated soils were assessed by following the C-13 tracer into microbial biomass and respiration. In addition, C-13-phospholipid fatty acids (PLFA) analysis was used to examine differential microbial utilization of the added substrates. Glucose and glutamate were metabolized similarly in soils of all three litter treatments. In contrast, the microbial community in the double wood soil respired more added phenol and oxalate, whereas microbes in the no inputs soil respired less added phenol and oxalate, than the control soil. Phenol was incorporated primarily into fungal PLFA, especially in soil of the double wood treatment. The addition of all four substrates led to enhanced degradation of soil organic matter (priming) in soils of all three litter treatments, and was greater following the addition of phenol and oxalate as compared to glucose and glutamate. Priming was greater in the no inputs soil as compared to the control or doubled wood soils. These results demonstrate that altering plant inputs to soil can lead to changes in microbial utilization of C compounds. It appears that many of these changes are the result of alteration in the size and composition of the microbial community. (c) 2006 Elsevier Ltd. All rights reserved.