Tree taxa and pyrolysis temperature interact to control the efficacy of pyrogenic organic matter formation
Tree taxa and pyrolysis temperature interact to control the efficacy of pyrogenic organic matter formation
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DOI：
10.1007/s10533-016-0245-1
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发表时间：
2016-10-01
期刊：
影响因子：
4
通讯作者：
Bird, Jeffrey A.
中科院分区：
文献类型：
--
作者：
Hatton, Pierre-Joseph;Chatterjee, Subhasish;Bird, Jeffrey A.
我们所知甚少的树木物种分布的变化和森林火灾强度的增加可能会影响热解有机质（PyOM）或木炭，最重要的和持久的土壤有机质库之一的形成。出现这种限制的部分原因是前体木材在控制PyOM形成中的作用尚不清楚。目前的研究表明，树种和热解温度（200，300，450和600摄氏度）相互作用，以控制的物理化学结构的PyOM实验来自C-13/N-15-丰富的松banksania和红槭，两个重要的共同发生的裸子植物和被子植物树种从北美北温带交错带。补充的物理化学和热力学测量结果表明，不同的两种木材物种的炭化，PyOM中间体形成在较低的温度下从松树，表明树种调节PyOM形成的功效。特别是，我们报告的高分辨率数据描述了PyOM的综合化学结构（包括-C和-N），因为它们是形成的，这是由独特的分子水平上的见解，其不稳定的馏分补充。我们认为，树种和热解温度的相互作用反映了两个主要的树木类群，包括裸子植物，促进挥发物的损失，提高生物组分的热暴露更大的有效孔隙度的独特解剖特征。这项研究指出，与松林相比，枫树林中PyOM生产的温度阈值更高，导致前一种物种占主导地位的生态交错区中潜在的可降解性更高，吸附性更低的PyOM。
We know little about how shifts in tree species distribution and increases in forest fire intensity could affect the formation of pyrogenic organic matter (PyOM) or charcoal, one of the most important and persistent soil organic matter pools. This limitation arises partly because the role of the precursor wood in controlling PyOM formation is unclear. The current study shows how tree species and pyrolysis temperature (200, 300, 450 and 600 A degrees C) interact to control the physicochemical structure of the PyOM experimentally derived from C-13/N-15-enriched Pinus banksania and Acer rubrum, two important co-occurring gymnosperm and angiosperm tree species from North American boreal-temperate ecotones. Complementary physicochemical and thermodynamic measurements revealed different susceptibilities of the two wood species to charring, with PyOM intermediates formed at lower temperature from the pine, indicating that the tree species regulated the efficacy of PyOM formation. Particularly, we report high-resolution data describing the comprehensive chemical architecture of PyOM (both -C and -N) as they are formed, which are complemented by unique molecular-level insights on their labile fractions. We posit that the tree species and pyrolysis temperature interaction reflects distinctive anatomical features of the two major tree taxa, including greater effective porosity in gymnosperms that promote the loss of volatiles and enhance the heat exposure of bio-components. This study points to a higher temperature threshold for PyOM production in maple forests compared with pine forests, resulting in potentially more degradable and less sorbtive PyOM in ecotones dominated by the former species.