不同根系分泌物对稻田土壤可溶性有机碳组成的影响
时间:2018-10-26 11:37 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本研究以江西省红壤研究所水稻土长期定位试验田（始于1981年）为对象，分析了不添加任何根系分泌物（CK）、添加草酸（OCK）、添加乙酸（ACK）、和添加葡萄糖（GCK）四种处理对土壤可溶性有机碳（DOC）、土壤微生物量碳（MBC）及土壤酶活性的影响。结果表明：与CK处理相比，OCK与ACK处理的土壤MBC含量显著降低；GCK处理的MBC含量培养前期显著增加，后期无显著差异，各处理均能促进酶活性的提高。根系分泌物的添加能显著提高DOC的量，DOC结构分析表明，CK、OCK与GCK处理促进了土壤DOC中类富里酸与类腐殖酸物质的增多，而ACK处理促进类富里酸与类色氨酸物质增加。相关性分析表明，MBC与DOC呈显著负相关，纤文素酶活性与类富里酸与类胡敏酸物质含量及其所占比例呈正相关，酚类氧化物酶活性与类富里酸、类胡敏酸物质呈正相关，过氧化物酶与类溶解性微生物代谢产物和类胡敏酸物质含量及其所占比例呈正相关。综上所述，添加不同根系分泌物可以通过改变微生物和相关酶的活性影响DOC含量及其组成。29684 毕业论文关键词：根系分泌物；可溶性有机碳；微生物活性；酶活性 Effects of Different Root Exudates on the Composition of Soil Dissolved Organic Carbon in Paddy Soils Abstract: Based on the long-term fertilization experiment in paddy soil (started in 1981) in the Red Soil Institute of Jiangxi Province, China, the effects of adding no root exudates (CK), adding oxalic acid (OCK), adding acetic acid (ACK) and adding glucose (GCK) on soil dissolved organic carbon, soil microbes and enzyme activities were analyzed. Results show that, compared with CK, microbial biomass organic carbon decreased significantly on the OCK and ACK treatment. The GCK treatment increased the content of MBC significantly in the earlier stage of incubation, and there was no significant difference in the later stage. All the treatments can promote the increase of soil enzyme activity. The addition of root exudates significantly increased the content of DOC. The analysis of the DOC structure shows that the accumulation of humic acid-like and fulvic acid-like materials were promoted in CK、OCK and GCK treatments, while the ACK treatment promoted the fulvic acid-like and tryptophan-like materials. Correlation analysis indicated that MBC had significantly negative correlations with DOC. The activity of cellulase was positively correlated with the content and proportion of humic acid-like and fulvic acid-like materials. The activity of phenol was positively correlated with fulvic acid-like and humic acid-like. And there was a positive correlation between the content of soluble metabolic products-like and humic acid-like. As a whole, the addition of different root exudates can affect the content and composition of DOC by altering the activity of microorganisms and related enzymes. Key words: Root exudates；Dissolved organic carbon；Microbial activity；Enzyme activity 目 录 摘要 1 关键词 1 Abstract 1 Key words 1 引言 1 1 材料与方法 2 1.1 试验区 2 1.2 试验材料 2 1.3 试验设计 2 1.4 试验方法 2 1.5 数据处理 3 2 结果与分析 3 2.1 不同根系分泌物对微生物的影响 3 2.1.1不同根系分泌物对土壤微生物量碳的影响 3 2.1.2不同根系分泌物对酶活性的影响 3 2.2 不同根系分泌物对土壤DOC的影响 5 2.2.1不同根系分泌物对土壤DOC含量的影响 5 2.2.2不同根系分泌物对土壤DOC组成的影响 6 (责任编辑：qin) |