不同蛋白源有机肥分解过程中组成性质变化特征

Characteristics of composition and properties of organic fertilizers from different protein sources during decomposition

不同商品有机肥在组成和性质上存在极大差异,决定着其在土壤环境中分解规律的不同。采用元素分析、热重分析(TG)、傅里叶变换红外光谱(FTIR)等光谱技术,分析了3种蛋白源的商品(豆粕、骨粉、虾肽)有机肥分解过程中物质组成、官能团组成、元素组成以及理化性质的变化。经过12个月的矿化分解,3种有机肥的pH值、CEC和灰分含量显著升高;豆粕、骨粉、虾肽有机肥的胡富比分别增加至1.87、1.47和3.69倍,腐殖化程度均显著增强。TG结果显示豆粕有机肥蛋白质含量减少,高分子含碳复合物增加,除骨粉有机肥碳水化合物向低温偏移外,3种有机肥其余失重峰均向高温方向偏移,稳定性增加。豆粕有机肥的矿化率最高为60.38%,分别是骨粉和虾肽有机肥的1.65和1.6倍;除P和Mg两种元素外,N、K、Ca、Fe、Mn、Cu和Zn均是豆粕有机肥释放率最高。FTIR结果表明3种有机肥中脂肪族、蛋白质及糖类逐渐分解,蛋白质的结构发生改变。3种有机肥在分解过程中,蛋白质含量减少,有机碳含量增加,有机质的稳定性增强;豆粕有机肥具有最高的碳氮百分含量,矿化率和养分释放率均高于骨粉和虾肽有机肥,植物源的豆粕有机肥在农田中肥效相对较快。

There are great differences in the composition and properties of different commercial organic fertilizers,which determines the different decomposition rules of different commercial organic fertilizers in the soil environment.In this study,elemental analysis,thermogravimetric analysis(TG)and Fourier transform infrared spectroscopy(FTIR)were used to analyze the changes of material composition,functional group composition,element composition and physicochemical properties during the decomposition of organic fertilizers from three kinds of protein sources,including soybean meal(SM),bone meal(BM),shrimp peptide(SP).After 12 months of decomposition,the pH value,CEC and ash content of the three kinds of organic fertilizer increased significantly,and the HA/FA of SM,BM and SP organic fertilizer increased to 1.87,1.47 and 3.69 times,respectively,and the humification degree was significantly enhanced.The results of TG analysis showed that the protein content of soybean meal organic fertilizer decreased and the polymer carbon complex increased.Except for the carbohydrate of bone meal organic fertilizer shifted to low temperature,the weight loss peaks of three kinds of organic fertilizer shifted to high temperature and the stability increased.The highest mineralization rate of SM was 60.38%,which was 1.65 and 1.6 times higher than that of bone meal and shrimp peptide organic fertilizer,respectively.Except for P and Mg,N,K,Ca,Fe,Mn,Cu and Zn had the highest release rate of SM.FTIR results showed that aliphatic groups,proteins and sugars in the three kinds of organic fertilizers decomposed gradually,and the structure of proteins changed.In the process of decomposition of the three kinds of organic fertilizers,the protein content decreased,the organic carbon content increased,and the stability of organic matter enhanced.SM organic fertilizer has the highest carbon and nitrogen content,mineralization rate and nutrient release rate are higher than BM and SP organic fertilizer.Plant-derived SM organic fertilizer has relatively fast fertilizer effect in farmland.