从以植物、鸡粪、生活垃圾、污泥、牛粪和杂草为主要原料的6种堆肥产品和草炭中提取胡敏酸类物质,对他们的激发、发射、同步和三维荧光光谱进行了研究.结果表明:各荧光谱图中,草炭胡敏酸特征荧光峰出现在最大波长处,植物、牛粪和生活垃圾堆肥胡敏酸次之,鸡粪和杂草堆肥胡敏酸紧接其后,污泥堆肥胡敏酸最低,并且含有较强的类蛋白荧光.各类堆肥的类富里酸荧光峰强度与类胡敏酸荧光峰强度的比值从小到大及腐殖质化程度由高到低均依次为0.708(草炭堆肥),0.893(植物堆肥),0.932(牛粪堆肥),0.940(生活垃圾堆肥),1.155(杂草堆肥),1.206(鸡粪堆肥)和1.521(污泥堆肥).相对于草炭胡敏酸,堆肥胡敏酸普遍分子结构简单、芳构化程度较低,且具有较强的土壤元素活化能力,并且植物、牛粪和生活垃圾堆肥的胡敏酸在增大土壤环境容量及降低污染土壤中重金属移动性方面效果最佳.
Humic acids(HA) extracted from grass peat and six types of composts based on plants, fowl manure, domestic waste, sludge, dairy manure and weeds as the raw materials were studied. The fluorescence emission spectra, excitation spectra, synchronous fluorescence and three-dimensional excitation emission matrix fluorescence of the humic acids were investigated. Of all the fluorescence results, HA from grass peat had characteristic peaks of longest wavelength followed by HA from compost based on plants, dairy manure, domestic waste, fowl manure, weeds and sludge, in decreasing order. In addition, HA from composts based on sludge had high strength peaks, imlicating the existence of proteins. The samples had obviously different ratios of the strength of the fulvic-like peak to the humic-tikc peak, with values of 0. 708 ( grass peat) , 0. 893 ( compost based on plants) , 0. 932 (compost based on dairy manure), 0. 940 (compost based on domestic waste), 1. 155 (compost based on weeds), 1. 206 (compost based on fowl manure) and 1.521 (compost based on sludge ). The molecular structure of HA from the composts was not complicated and of low aromatization relative to that from grass peat. The HA from these composts had soil activation ability. HA from the composts based on the plants, dairy manure and domestic waste can increase the soil environment capacity and efficiently reduce the mobility of heavy metals in the polluted soil.