川西高寒生态系统不同海拔土壤动物对冬季凋落叶腐殖化过程的影响

发布时间：2018-07-07 20:24

本文选题：腐殖化 + 土壤动物　；参考：《生态学报》2017年05期

【摘要】：凋落叶在冬季的腐殖化过程是高寒生态系统土壤有机质形成和碳固定的重要阶段,并可能受到严酷冻结环境下仍具有一定活性的土壤动物的影响,但缺乏必要的关注。因此,以川西高山峡谷区海拔3000、3600、4000m的高寒森林和草甸典型凋落叶为研究对象,采用不同孔径大小的凋落物网袋去除土壤动物的方法,根据凋落叶的自然腐解过程,于2013年11月—2014年4月研究了不同冻融时期(冻结前期、深冻期、融化期)土壤动物对凋落叶腐殖化过程的作用。结果表明:通过对色调系数(Δlog K)和光密度值(E_4/E_6)值的分析,在高寒生态系统中,冬季随着温度的降低土壤动物促进了凋落叶的腐殖化,而随着温度的升高土壤动物抑制了凋落叶的腐殖化。深冻期土壤动物对海拔3000m的森林凋落叶腐殖化过程具有显著促进作用;在冻结前期土壤动物对海拔3600m森林凋落叶腐殖化过程具有显著促进作用;而融化期土壤动物对海拔4000m的草甸凋落叶腐殖化过程具有显著的抑制作用;其他海拔和时期没有显著影响。冻结初期土壤动物对凋落叶的腐殖化速率的作用高于深冻期和融化期,腐殖化度在深冻期达到最大值。这些结果表明气候变化情景下冬季变暖可能导致土壤动物抑制凋落物腐殖化,减少凋落物向土壤有机质的转化。
[Abstract]:The humification process of litter leaves in winter is an important stage of soil organic matter formation and carbon fixation in alpine ecosystem, and may be affected by soil animals that are still active in severe freezing environment, but lack of necessary attention. Therefore, the alpine forest and the typical litter leaves of meadow in the alpine forest and meadow in the alpine canyon region of western Sichuan were studied. The method of removing soil animals with different diameter litter net bag was used, according to the natural decay process of the fallen leaves. From November 2013 to April 2014, the effects of soil animals on the process of leaf decay were studied in different freezing and thawing periods (pre-freezing period, deep freezing period and melting period). The results showed that through the analysis of 螖 log K and E _ S _ 4 / E _ (6), in the alpine ecosystem, soil animals promoted the humification of litter leaves with the decrease of temperature in winter. With the increase of temperature, the humification of littered leaves was inhibited by soil animals. Soil fauna significantly promoted the decaying process of forest litter leaves at 3000m altitude during the deep freezing period, and promoted the decaying process of forest litter leaves at 3600m altitude during the early freezing period. Soil animals at melting stage had significant inhibitory effect on litter decaying process of meadow at an altitude of 4 000 m, but no significant effect was found at other stages. In the early stage of freezing, the humification rate of soil animals was higher than that of deep freezing period and thawing stage, and the humification degree reached the maximum value in deep freezing period. These results suggest that winter warming in climate change scenarios may lead to the inhibition of litter humification and the reduction of litter to soil organic matter transformation by soil animals.
【作者单位】：四川农业大学林业生态研究所;林业生态工程重点实验室;
【基金】：国家自然科学基金重点项目(31270498,31170423) 四川省杰出青年学术与技术带头人培育项目(2012JQ0008,2012JQ0059) 中国博士后科学基金特别资助项目(2012T50782) 高等学校博士学科点专项科研基金(20135103110002)
【分类号】：S714

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