东北黑土有机质组分与结构的研究进展

在全球气候变化背景下研究土壤有机质的转化过程对于评价陆地生态系统碳截获潜力具有重要意义,而土壤有机质的循环特征及其稳定性与土壤有机质的组成和结构密切相关.东北黑土区是我国重要的商品粮基地,近年来,黑土有机质含量呈显著下降趋势,造成黑土肥力和质量的严重退化.本文通过文献资料的整理,总结了不同农田管理措施下黑土土壤有机质的消长动态、组分变化以及结构特征的研究现状,并探讨了研究中存在的问题.开垦和耕作导致土壤有机质总量、活性组分以及腐殖物质含量的显著降低,而平衡施用化肥和有机肥是维持和提升土壤有机质数量和质量的有效途径,长期有机无机配施使土壤有机质结构趋于简单化,有利于土壤肥力的保持.黑土有机质组分化学结构变化的驱动机制是值得人们长期探索的问题.

Review of soil organic matter fractions and structure of black soil in northeast China

In the case of global climate change, it is essential to study the transformation process of soil organic matter (SOM) for improving the potential of terrestrial carbon sequestration. SOM cycle and stabilization are significantly related to its fractions and structure characteristics. Black soil in northeast China is well known of its high SOC stocks, it plays a crucial role in national food production. Recently, SOM content of black soil decreased dramatically, which resulted in the degradation of soil fertility and quality. The current advances of SOM dynamics, fractions and structure of black soil in northeast China as influenced by different agricultural managements were reviewed in this paper, and the further researches on SOM of black soil were also discussed. It showed that reclamation and tillage resulted in total SOM content, labile fractions and humic substance decreased markedly, the content and quality of SOM promoted as the application of optimum chemical fertilizer and organic manure, and SOM structure became simpler with long-term application of chemical fertilizer plus organic manure, which was positive to increase soil fertility. The mechanism of change on SOM fractions and its structure need to be further understood.