【摘要】 :以 2 1年长期定位试验土样为材料 ,对不同施肥处理土壤有机质的含量、氧化稳定性 ,胡敏酸的能态、结构及级分组成等进行了研究。结果表明 ,与试验前土壤有机质相比 ,长期不施肥土壤有机质下降 1 .0 4 g/kg;秸秆加休闲处理 ,有机质含量减少 0 .48g/kg;长期单施化肥基本可以维持土壤有机质水平 ;长期施用有机肥 ,可显著提高土壤有机质水平 ,比试验前土壤增加1 .1 7～ 2 .85g/kg。与无肥处理相比 ,施用有机肥使有机质的氧化稳定性降低 ,而化肥、休闲处理则使有机质的氧化稳定性升高。胡敏酸能态高低顺序是厩肥 >秸秆 >无肥 >化肥 >休闲。与定位 1 0年时相比 ,各处理土壤胡敏酸能态有所降低。长期施用有机肥土壤胡敏酸分子趋于简单 ,活化度提高 ,胡敏酸中结构相对简单的级分增多 ,而长期单施化肥则呈现相反趋势更多还原

【Abstract】 Soil samples taken from a long term fixed spot experiment (21 years) with different fertilization were used to study the content and oxidation stability of soil organic matter, the energy state, structure and fractions of soil humic acids. The main results showed that compared with the content of organic matter before experiment, the soil organic matter content decreased by 1.04 g/kg with no fertilization ,and decreased by 0.48 g/kg with fallow, application of chemical fertilizer for 21 years could maintain the level of soil organic matter, and applying organic materials (yard manure or corn straw) caused organic matter to be increased by 1.17～2.85 g/kg. Application of organic materials reduced the oxidation stability of soil organic matter as compared with no fertilization. The opposite was true to the treatments of chemical fertilizer or fallow. After 21 years, the soil humic acid energy state was lower than that after 10 years. The energy state order of different treatments was yard manure>straw>no fertilization>chemical fertilizer>fallow. Application organic materials for a long time made the molecular of humic acid become simpler, and increased the humic acid activity and its simple fractions. The results of application of chemical fertilizer was on the contrary.更多还原