Factors controlling mineralization of soil organic matter in the Eurasian steppe
Factors controlling mineralization of soil organic matter in the Eurasian steppe
复制标题
DOI：
10.1016/j.soilbio.2007.11.015
复制
发表时间：
2008-04-01
影响因子：
9.7
通讯作者：
Kosaki, Takashi
中科院分区：
文献类型：
--
作者：
Kadono, Atsunobu;Funakawa, Shinya;Kosaki, Takashi
为了了解欧亚草原土壤有机质（SOM）的动态，通过对土壤和气象特性的测试来估算潜在矿化有机碳（PMC）和氮（PMN）的数量。在乌克兰和哈萨克斯坦的农田、森林、草地和沙漠生态系统共采集了41份表层土壤样品。在恒温恒湿条件下，对新鲜土壤进行133 d的培养，监测土壤的CO、排放和矿质氮。采用CO2和矿质氮累积曲线拟合模型确定PMC和PMN，测试土壤性质包括土壤pH、砂、粉和粘土含量、轻组分（LF, < 1.6 g cm(-3)）和重组分（HF）的碳氮含量以及LF和HF的C/N比。考虑的气象性质是平均动物温度和降水。多元回归分析表明，土壤有机碳（0C）与土壤有机碳（LFC）含量的相关性较好，土壤有机碳（LFC）含量与粘土含量的相关性较好。同样，土壤中氮素含量（LFN）和粘土含量对PMN的测定效果较好。这些结果表明，粘土缔合的OM、LFC和LFN具有部分不稳定的性质。森林和草地样地的PMC和PMN较高归因于较高的LFC和LFN，而农田样地较低的LFC和LFN表明与粘土相关的OM对PMC和PMN的贡献相对较高。(C) 2007 Elsevier Ltd.版权所有。
To understand the dynamics of soil organic matter (SOM) in the Eurasian steppe, several soil and meteorological properties were tested in order to estimate the amounts of potentially mineralizable organic carbon (PMC) and nitrogen (PMN). Total 41 surface soil samples were collected in Ukraine and Kazakhstan from cropland, forest, grassland, and desert ecosystems. The fresh soils were incubated for 133 days under constant temperature and moisture conditions, and the CO, emissions and the mineral N from the soils were monitored. PMC and PMN were determined by fitting models to the cumulative curves of the CO2 and the mineral N. Tested soil properties included soil pH, sand, silt and clay contents, carbon and nitrogen contents of light fraction (LF, < 1.6 g cm(-3)) and heavy fraction (HF), and C/N ratio of LF and HF. The meteorological properties considered were mean animal temperature and precipitation. Using multiple regression analysis with the stepwise method, PMC was well estimated by carbon content of LF (LFC) and clay content, compared to the simple correlation with orgarnic carbon (0C). similarly, PMN was better determined by nitrogen content of LF (LFN) and clay content. These results sugggest the partially labile nature of clay-associating OM and of LFC and LFN. The higher PMC and PMN in the forest and grassland sites Would be attributed to the higher LFC and LFN, while the lower LFC and LFN in cropland sites would suggest the relatively higher contribution of clay-associating OM to PMC and PMN. (C) 2007 Elsevier Ltd. All rights reserved.