为探讨长江流域中植物和土壤的木质素特征,应用碱性氧化铜分解一气相色谱检测法对长江流域的典型植物和土壤样品中的木质素进行了测定分析.结果表明,长江流域植物具有较宽的C/V和S/V范围,可以区分出单子叶和双子叶植物、湿生和非湿生植物;长江流域土壤则呈现出中下游地区较上游地区有机碳中木质素含量较高且降解程度较小的趋势,南北支流的差异主要表现在南支土壤中有机碳含量(OC)较高、碳同位素比值δ^13C较高且木质素含量较高.与世界其它地区相比,长江流域的植物和土壤的木质素特征具有明显的流域自身特征,这些特征为探讨陆源有机物自长江向东海陆架输送和埋藏等科学问题提供更可靠和更丰富细致的背景信息.
Plant and soil samples collected from the Yangtze River (Changjiang) drainage basin were analyzed for carbon content, stable carbon isotopes and lignin phenol content to investigate the characteristics of terrigenous organic matter. The signature of lignin phenols of the vascular plant tissues revealed significant differences in C/V ( ratio of cinnamyl phenols to vanillyl phenols) among monocotyledon ( 1.42 ) , dicotyledon (0.43) and phreatophytes (2.84). Elevated lignin concentration was found in soils from middle/down reaches. The (Ad/Al)v (ratio of vanillic acid to vanillin) of the soil samples suggested that the lignin composition in soils from up reach was more degraded. Soils of northern tributaries and southern tributaries could be discriminated by OC% , δ^13C and Y8 (yields of lignin phenols) values over the whole basin. From a comparison of the lignin compositions of various plants and soils around the world, the lignin characteristics in the Yangtze River drainage basin are distinctive. Therefore, reliable and detailed information is obtainable for biogeocbemistry studies of terrestrial organic matter from the Yangtze River to the East China Sea.