| 植物-土壤有机质转化过程中的碳同位素组成变化 |
| 点此下载全文 |
| 引用本文：宁有丰,刘卫国,安芷生.2005.植物-土壤有机质转化过程中的碳同位素组成变化[J].地球学报,26(z1):-236. |
| DOI：10.3975/cagsb.2005.s1.78 |
| 摘要点击次数: 3148 |
| 全文下载次数: 2123 |
|
|
| 中文摘要:土壤有机质的碳同位素信息反映了上部的植被和气候状况，但植物体在被微生物分解、利用、转变为土壤有机质的过程中会产生碳同位素的分馏。本研究探了高山草甸和典型草原两种不同气候、生态环境条件下，植物转变为土壤有机质过程中的碳同位素组成变化。结果显示：在太白山高海拔地区的4个采样点，表土的δ13Corg值均随深度的增加而逐渐偏正，到距离地表10-15cm左右时，土壤的δ13Corg值基本稳定。经过长期分解稳定以后的土壤有机质的δ13C值要比其源植被约偏正1.65‰-2.27‰左右，平均约偏正1.9‰左右。在内蒙草原样地的4个采样点，亦表现出与太白山相似的变化：土壤样品的δ13Corg值从地表开始，随着深度的增加而逐渐偏正，到约距离地表10cm左右深度后，δ13Corg值逐渐达到稳定，在距地表10-16cm间基本稳定不变。在该深度土壤的δ13Corg值比它上面生长的植物的δ13C值要分别偏正1.3‰、1.4‰、1.4‰、1.2‰，4块样地平均偏正约1.3‰左右。本研究表明，在运用土壤有机碳同位素反淀古植被和古气候变化时，应考虑到不同气候、生态环境中植物转化为有机质过程中的碳同位素分馏影响。 |
| 中文关键词:碳同位素 土壤 植被 转化 |
| |
| Carbon Isotopic Variation of the Organic Matter During the Plant-Soil Transformation |
|
|
| Abstract:Carbon isotopic composition of the soil organic mateer (SOM) reflects the situation of the growing plants and climates. However, when the plants are decomposed and utilized by the microbe, carbon isotopic fractionation is likely to occur. The authors studied the variation of the carbon isotopic composition during the transformation of plants into SOM in two different climates and en-vironments of alpine meadow and typical grasslang. Some results have been obtained: At the four sampling eites in the Taibai Moun-tain of high altitude, the soil δ13Corg values gradually become ore positive with the increasing depth, and the soil δ13Corg values gradually become more positive with the increasing depth, and the soil δ13Corg values be-come stable at 10-15cm. The soilδ13Corg values of longtime stabilization are some 1.65‰-2.27‰(1.9‰ on average) more positive to the source plants. At the four grasslang sampling sites in Inner Mongolia, similar results have been obtained: the soil δ13Corg values become more positive with the increasing depth, and tend to be stable at 10-16cm. The soil δ13Corg values of the 10-16 cm depth is 1.3‰,1.4‰, 1.4‰, and 1.2‰ more positive to the source plants, respectively. When we apply the soil organic carbon isotope to the study of paleovegetation and paleoclimate, we should consider the influence of the carbon isotopic fractionation during the transfor-mation of plants into SOM in different climates and environments. |
| keywords:carbon isotope soil plant transform |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|
