Effects of forest fragmentation on organic carbon pool densities in the Mongolian forest-steppe
Effects of forest fragmentation on organic carbon pool densities in the Mongolian forest-steppe
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DOI：
10.1016/j.foreco.2018.10.054
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发表时间：
2019-02-15
影响因子：
3.7
通讯作者：
Tuya, Daramragchaa
中科院分区：
文献类型：
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作者：
Dulamsuren, Choimaa;Klinge, Michael;Tuya, Daramragchaa
在蒙古森林草原交错带的西伯利亚落叶松林的大小和程度的隔离影响地上和地下碳库密度的假设进行了测试。研究问题是基于这样一个事实，即小气候和干旱敏感性的树干木材生产的早期表现出不同的立场大小和隔离在这个交错带。与我们的假设相反，我们没有发现树木生物量和矿质土壤的有机碳储量密度有显着差异。有机层的深度、碳含量和碳储量密度随林分规模的增加而增加，但不是总生态系统碳储量密度的主要决定因素。然而，增加深度和增加腐殖质含量的有机层与林分规模可以显着提高水分的有效性，从而促进森林更新。此外，减少有机层厚度和腐殖质含量，从而蓄水能力可能是以前观察到的干旱脆弱性较高的干木材形成的小森林站在蒙古森林草原的几个原因之一。生态系统总有机碳储量密度的平均碳储量密度为237 Mg C ha（-1），这与先前对蒙古北方森林的估计相吻合，证实了这样一种观点，即北方森林南部边缘的生态系统碳库密度低于气候更冷、永久冻土更深、更广的高纬度森林。
The hypothesis was tested that the size and the degree of isolation of Larix sibirica forests in the forest-steppe ecotone of Mongolia affects aboveground and belowground carbon pool densities. The research question was based on the fact that both microclimate and the drought sensitivity of stemwood production were earlier shown to differ with stand size and isolation in this ecotone. Contrary to our hypothesis, we did not find significant differences in the organic carbon stock densities of the tree biomass and the mineral soil. The depth, carbon content and carbon stock density of the organic layer increased with stand size, but was not a major determinant of total ecosystem carbon stock density. Nevertheless, the increasing depth and the increasing humus content of the organic layer with stand size could be significant by improving moisture availability and, thus, promoting forest regeneration. Furthermore, reduced organic layer thickness and humus content and thus water storage capacity could be one out of several causes of the previously observed higher drought vulnerability of stemwood formation in small forest stands of the Mongolian forest-steppe. A mean carbon stock density of 237 Mg C ha(-1) for total ecosystem organic carbon stock density matches with earlier estimates for Mongolia's boreal forest corroborating the view that the ecosystem carbon pool density at the southern edge of the boreal forest is lower compared to forests at higher latitudes with even colder climate and deeper and more widespread permafrost.