Temporal variation in surface and subsoil abundance and function of the soil microbial community in an arable soil
Temporal variation in surface and subsoil abundance and function of the soil microbial community in an arable soil
复制标题
DOI：
10.1016/j.soilbio.2013.02.006
复制
发表时间：
2013-06-01
影响因子：
9.7
通讯作者：
Kandeler, Ellen
中科院分区：
文献类型：
--
作者：
Kramer, Susanne;Marhan, Sven;Kandeler, Ellen
农业生态系统微生物生态学的许多研究集中在表层土壤，而管理措施和季节对耕作区以下土壤微生物群落组成和功能的影响在很大程度上被忽视。深层土壤具有很高的储存碳的潜力;因此，任何管理驱动的底土中微生物的刺激或抑制都可能影响农业用地的生物地球化学循环。本研究的目的是了解土壤管理是否影响微生物群落在表土（0 - 10厘米），根区下耕层（40 - 50厘米），和无根区（60 - 70厘米）。在田间试验中，不同作物[小麦（Triticum aestivum L.）和玉米（Zea mays L.）]和农业管理策略（凋落物修正），我们分析了微生物生物量的磷脂脂肪酸（PLFA）和酶的活性参与C-循环（β-葡萄糖苷酶，N-乙酰-β-D-氨基葡萄糖苷酶，β-木糖苷酶，苯酚和过氧化物酶）在一个深度样带超过两年。小麦栽培导致更高的细菌和真菌生物量以及更高的酶活性在大多数采样日期相比，玉米栽培地块，这种效果是可见的50 cm深度。凋落物的应用增加了细菌和真菌的生物量以及水解酶的活性，但效果只在表土明显。在冬季高微生物生物量和酶的活动，测量在所有的土壤层，可能是由于增加的动员和转运的有机物质到更深的土壤。水解酶活性随深度的增加而降低，而氧化酶活性不随深度的增加而降低甚至增加。这可能是由于水解酶和氧化酶的吸附机制不同。特定的酶活性（酶活性每微生物生物量）较高，在较深的层和可能的原因进行了讨论。(C)2013爱思唯尔有限公司保留所有权利。
Many studies of the microbial ecology of agricultural ecosystems focus on surface soils, whereas the impacts of management practice and season on soil microbial community composition and function below the plough zone are largely neglected. Deep soils have a high potential to store carbon; therefore any management driven stimulation or repression of microorganisms in subsoil could impact biogeochemical cycling in agricultural sites. The aim of this study was to understand whether soil management affects microbial communities in the topsoil (0-10 cm), rooted zone beneath the plough layer (40-50 cm), and the unrooted zone (60-70 cm). In a field experiment with different crops [wheat (Triticum aestivum L.) and maize (Zea mays L.)] and agricultural management strategies (litter amendment) we analysed microbial biomass as phospholipid fatty acids (PLFAs) and enzyme activities involved in the C-cycle (beta-glucosidase, N-acetyl-beta-D-glucosaminidase, beta-xylosidase, phenol- and peroxidase) across a depth transect over a period of two years. Wheat cultivation resulted in higher bacterial and fungal biomass as well as higher enzyme activities at most sampling dates in comparison to maize cultivated plots, and this effect was visible to 50 cm depth. Litter application increased bacterial and fungal biomass as well as hydrolytic enzyme activities but effects were apparent only in the topsoil. In winter high microbial biomass and enzyme activities were measured in all soil layers, possibly due to increased mobilization and translocation of organic matter into deeper soil. Hydrolytic enzyme activities decreased with depth, whereas oxidative enzyme activities showed no decrease or even an increase with depth. This could have been due to differing sorption mechanisms of hydrolytic and oxidative enzymes. Specific enzyme activities (enzyme activity per microbial biomass) were higher in the deeper layers and possible reasons are discussed. (C) 2013 Elsevier Ltd. All rights reserved.