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本研究通过采用氮的K边X光吸收近边结构(XANES)技术来了解森林土壤有机氮,以此深入研究土壤中有机氮种类与其转化的定量关系.土壤样品采自台湾中部的云杉、铁杉林与草地.结果表明,氮的XANES可以揭示样品中不同的氮的种类.在土壤腐植质、可溶性氮及本体土壤中胺态及吡咯氮占了主要的比率.然而不同处理及植被下的土壤样品氮的种类分布是不同的.云杉与铁杉土壤可溶性有机氮在402.3 eV能量处有显著的差异.在A层土壤中,吡啶类氮含量要显著高于O层土壤,说明氮在不同土层中的转化率存在极大的差异,这种变化对于氮在森林土壤中的循环将起重要作用.图3表1参8.“,”The forest soil organic N was investigated using N K-edge X-ray absorption near-edge structure (XANES) to gain an insight into the relationship between N speciation and its transformation in quantity. Soil samples were collected from spruce, hemlock and pine forests in central Taiwan. Results showed that various organic N types could be revealed by XANES spectra. Amide and pyrrolic N are the major parts of the composition in the humic substance, soluble organic nitrogen and original soils. The relative distribution of N speciation differed in treatments and vegetations samples. The spruce had a significant difference from the hemlock in soluble organic nitrogen (SON) spectra at 402.3 eV energy peak. In the A-horizon soils, the relative amount of pyridinic N was much higher than that in the O-horizon soils, indicating N transformation in quantity in the mineral horizon was different from that in the organic horizon, which might play an important role in N cycling of forest ecosystems.