长期施肥下浙江稻田不同颗粒组分有机碳的稳定特征  

Effect of Long-term Fertilizer Application on the Stability of Organic Carbon in Particle Size Fractions of a Paddy Soil in Zhejiang Province,China

作　　者：毛霞丽[1,2] 陆扣萍[1,2] 孙涛[1,2] 张小凯[1,2] 何丽芝 王海龙[1,2] 

机构地区：[1]浙江农林大学环境与资源学院,临安311300 [2]浙江农林大学浙江省森林生态系统碳循环与固碳减排重点实验室,临安311300

出　　处：《环境科学》2015年第5期1827-1835,共9页Environmental Science

基　　金：浙江省科技厅公益性技术应用研究项目(2013C32025);浙江农林大学科研发展基金(人才引进)项目(2010FR097)

摘　　要：依托浙江水网地区稻田长期定位施肥试验(1996~2013年),利用固态13C核磁共振波谱技术,研究长期不同施肥措施下土壤各颗粒组分有机碳含量及其化学结构特征.结果表明,与不施肥对照(CK)相比,秸秆与化肥配施(NPKRS)、栏肥与化肥配施(NPKOM)、单施化肥(NPK)和单施栏肥(OM)处理均显著(P<0.05)增加了砂粒(2~0.02 mm)、粉粒(0.02~0.002mm)和黏粒(<0.002 mm)组分中有机碳含量;而单施秸秆(RS)处理仅显著增加砂粒组分有机碳含量.此外,与单施化肥处理相比,有机肥和化肥配施促进了新增有机碳在粉粒和黏粒组分的分配,更有利于新增有机碳的稳定.应用13C-NMR波谱技术进行结构表征,结果表明粉粒和黏粒组分有机碳的化学结构存在明显差异,粉粒组分烷氧碳、芳香碳的相对含量高于黏粒,而烷基碳、羰基碳的相对含量低于黏粒.长期有机肥与化肥配施下粉粒和黏粒烷基碳相对含量较单施有机肥处理分别降低9.1%~11.9%和13.7%~19.9%,烷氧碳的相对含量则分别增加2.9%~6.3%和13.4%~22.1%,表明有机肥与化肥配施处理降低了粉粒和黏粒组分有机碳的分解程度.长期单施化肥处理下粉粒和黏粒组分有机质的芳化度和疏水性低于单施有机肥处理和不施肥处理,有机质的矿化稳定性较低.长期有机肥与化肥配施,尤其是NPKOM处理,通过增加化学抗性化合物和碳水化合物的积累,并且减缓活性组分的分解提高粉粒和黏粒组分有机碳含量,是促进稻田土壤有机碳可持续积累的有效措施.Effects of chemical fertilizers and organic manure on the soil organic carbon( SOC) content in particle size fractions of paddy soil were investigated in a 17-year long-term fertilization field experiment in Zhejiang Province,China. The inherent chemical composition of silt- and clay-associated SOC was evaluated with solid-state13C-NMR spectroscopy. Compared to CK( no fertilizer treatment),NPKRS( NPK fertilizers plus rice straw),NPKOM( NPK fertilizers plus organic manure),NPK( NPK fertilizers) and OM( organic manure alone) treatments significantly( P < 0. 05) increased the SOC content of sand-( 2-0. 02 mm),silt-( 0. 02-0. 002mm) and clay-sized( < 0. 002 mm) fractions. However,no significant difference was observed in the accumulation of silt- and clayassociated SOC between CK and rice straw( RS) treatments. Besides,in comparison with plots applied with NPK fertilizers alone,combined application of organic amendments and NPK fertilizers facilitated the storage of newly sequestered SOC in silt- and clay-sized fractions,which could be more conducive to the stability of SOC. Based on13C-NMR spectra,both silt and clay fractions were composed of Alkyl-C,O-alkyl-C,Aromatic-C and carbonyl-C. Changes in the relative proportion of different C species were observed between silt and clay fractions: the clay fraction had relatively more Alkyl-C,carbonyl-C and less O-alkyl-C,Aromatic-C than those in the silt fraction. This might be ascribed to the fact that the organic matter complexed with clay was dominated by microbial products,whereas the silt appeared to be rich in aromatic residues derived from plants. The spectra also showed that the relative proportion of different C species was modified by fertilization practices. In comparison with organic amendments alone,the relative proportion of Alkyl-C was decreased by 9. 1%-11. 9% and 13. 7%-19. 9% under combined application of organic amendments and chemical fertilizers,for silt and clay,respectively,and that of O-alkyl-C was increased by 2. 9%-6. 3% and 13. 4%-22. 1%,respecti

关 键 词：长期定位试验 稻田土壤 施肥 颗粒分组 13C核磁共振波谱技术 化学结构 

分 类 号：X712[环境科学与工程—环境工程]