“三江并流区”暗棕壤腐殖质特性及其与土壤结构的关系

Relationship on Dark-brown Soil Humus Distribution and Soil Structure in Three Parallel Rivers Area

采用野外调查与室内分析相结合的方法,研究了"三江并流区"5个典型暗棕壤剖面腐殖质特性及其与土壤结构的关系,以期为该区土地资源的保护提供有利依据。结果表明,腐殖质含量与有机碳的分布规律一致,即腐殖质层>淋溶层>淀积层>母质层。腐殖质组成中,以胡敏素(HA)占绝大多数。HA分子复杂程度较高,化学稳定性较强。土壤腐殖化程度与富里酸FA分子复杂程度和化学稳定性一致,随年降雨量的增加而降低,依次为哈巴雪山>千湖山>梅里雪山>云岭>高黎贡山。1～0.5mm粒径团聚体含量居多,且粒径含量与腐殖酸含量均随年均温的升高而降低,依次为高黎贡山>梅里雪山>千湖山>哈巴雪山>云岭。研究结果表明,表层有机碳与1～0.5mm粒径含量相关,胡敏酸和富里酸与1～0.5,0.5～0.25mm粒径含量呈显著相关。

Properties of humus and soil structure of five typical dark brown soil profile in ＂Three Parallel Rivers Area＂ were studied in the lab and through field survey as well to gain a better knowledge to protect the land resources in the view and provide a favorable basis. Results show that the content of humus and the distribution rule of organic carbon is the same, that is humus layer〉leached layer〉deposition layer 〉parent layers. Humin takes the major part in the Humus composition. HA have a higher degree of molecular complexity and chemical stability strong. The degree of soil humus and the complexity of the FA molecules and the chemical stability is the same, with the increase in annual rainfall decreases, followed by Haba Snow Mountain〉Qianhu Mountain〉Meili Snow Mountain〉 Yunling〉Gaoligongshan. The content of water-stable aggregate are mostly content of 140.5 mm diameter, and thesize of content and humic acid levels were elevated with the annual average temperature decreases, followed by Gaoligongshan〉Meili Snow Mountain 〉Qianhu Mountain〉Haba Snow Mountain〉Yunling. Surface organic carbon is related to the content of the 1-0.5 mm size, humic acid and fulvic acid are also significantly related to particle size of 1-0.5 mm, 0.5- 0.25 mm content.