Priming effects in different soil types induced by fructose, alanine, oxalic acid and catechol additions
Priming effects in different soil types induced by fructose, alanine, oxalic acid and catechol additions
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DOI：
10.1016/j.soilbio.2004.07.037
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发表时间：
2005-03-01
影响因子：
9.7
通讯作者：
Marschner, B
中科院分区：
文献类型：
--
作者：
Hamer, U;Marschner, B
已经确定的是，向土壤中添加某些基质可以加速或延缓土壤有机质的矿化。但到目前为止，对这些所谓的“启动效应”的研究几乎完全是用可耕地土壤和植物残留物或葡萄糖作为添加剂进行的。在这项研究中。通过26 d的培养试验，研究了c -14统一标记基质果糖、丙氨酸、草酸和儿茶酚对玉米和黑麦栽培下两种森林土壤（Haplic Podzol和Dystric Cambisol）和一种耕地土壤（Haplic Phaeozem）不同层位土壤有机碳矿化的影响。除对照组外，所有样品均添加13.3杯底物- c mg(-1) C-org。在孵育过程中，每小时测量CO2的释放量，并在不同的时间间隔测定(CO2)-C-14的量。在几乎所有的土壤中，一种或几种添加的底物都能引起引发效应。最强烈的正启动效应是由果糖和丙氨酸诱导的，并且发生在Haplic Podzol的b层，那里的有机碳矿化几乎翻了一番。在其他土壤样品中，这些基质使有机碳矿化率提高了+ 10 ~ +63%。除了在Haplic Podzol的EA层，儿茶酚的添加通常会使有机碳矿化减少- 12%至-43%，在那里，有机碳携带的二氧化碳演化增加了+ 46%。草酸也能诱导负启动效应和正启动效应，启动效应范围从- 24%到+ 82%。数据表明，启动效应在森林土壤和耕地土壤的表层和下层都普遍存在。虽然在本研究中使用了各种各样的土壤，但土壤性质和启动效应之间的关系无法确定。因此，不可能根据相对容易测量的土壤化学和物理性质来预测启动效应的发生和大小。然而，数据表明，在含有低生物降解性有机碳的森林土壤中，积极的启动效应最为明显，在那里，添加的基质可能作为微生物代谢的重要能量来源。(C) 2004 Elsevier Ltd.版权所有。
It is well established that certain substrate additions to soils may accelerate or retard the mineralisation of soil organic matter. But up to now, research on these so called 'priming effects' was almost exclusively conducted with arable soils and with plant residues or glucose as additives. In this study. the effects of the uniformly C-14-labelled substrates fructose, alanine, oxalic acid and catechol on the mineralisation of soil organic carbon (SOC) from different horizons of two forest soils (Haplic Podzol and Dystric Cambisol) and one arable soil (Haplic Phaeozem) under maize and rye cultivation were investigated in incubation experiments for 26 days. Apart from the controls, all samples received substrate additions of 13.3 mug substrate-C mg(-1) C-org. During the incubation, CO2-evolution was measured hourly and the amount of (CO2)-C-14 was determined at various time intervals. In almost all soils, priming effects were induced by one or several of the added substrates. The strongest positive priming effects were induced by fructose and alanine and occur-red in the Bs horizon of the Haplic Podzol, where SOC mineralisation was nearly doubled. In the other soil samples, these substrates enhanced SOC mineralisation by + 10 to +63%. Catechol additions generally reduced SOC mineralisation by - 12 to -43% except in the EA horizon of the Haplic Podzol where SOC-borne CO2-evolution increased by + 46%. Oxalic acid also induced negative as well as positive priming effects ranging from - 24 to + 82%. The data indicate that priming effects are ubiquitously occurring in surface and subsoil horizons of forest soils as well as in arable soils. Although a broad variety of soils was used within this study, relationships between soil properties and priming effects could not be ascertained. Therefore, a prediction on occurrence and magnitude of priming effects based on relatively easily measurable chemical and physical soil properties was not possible. Nevertheless, the data suggest that positive priming effects are most pronounced in forest soils that contain SOC of low biodegradability, where the added substrates may act as an important energy source for microbial metabolism. (C) 2004 Elsevier Ltd. All rights reserved.