北京市两种沉积物和一种代表性土壤的氮素矿化特征及其预测

The Characteristics of Mineralization of Nitrogen and Prediction of Different Sediments and Soil in Beijing

在淹水条件下,采用间歇淋洗法研究了北京市2种沉积物和一种代表性土壤的氮素矿化过程,得到了各自的氮素矿化参数K,n和预测方程,结果表明其矿化潜力顺序为HH>TR>HK。3个处理的矿化速率在培养的前11d迅速增大,达到最大值后逐渐降低,最后趋于0;HH矿化速率峰值出现时间比HK和TR要早。矿化出来的氨氮高峰都出现在淋洗的第11天,之后逐渐降低,最后趋于一个较低的水平;相同时间内HH的矿化量要远远大于HK和TR。培养结束时各处理各层次有机质、总氮和固定态铵含量都表现为降低的趋势。矿化量中有一小部分来自固定态铵的释放,但由于所占比例较小可以忽略不计。

Under waterlogged incubation conditions, the nitrogen mineralization of two different sediments and a general Beijing＇s soil were investigated with the method of the intermittent leaching, besides their nitrogen mineralization parameters （K, n） and the prediction equation were gained. The results indicated that their mineralization potential was in the order：. Houhai sediment〉 Chaoyangqu soil 〉 Huankeyuan sediment. The rates of the N mineralization before the 11 incubation day are promptly augmenting to the maximal, and then the rates are gradually falling, at the end of incubation theirs are close to zero. The flood tide of nitrogen mineralization rates of HH sediment appeared earlier than HK and TR. The flood tide of ammonium in the N mineralization process appeared in the 11 day of leaching time, and the N mineralization quantity gradually got into a windless state. In the same period the N mineralization quantity of HH was further more than HK and TR. The content of organic matter,the total nitrogen and the fixed ammonium in the different treatments and levels at the end of incubation were lessened, and a few of N mineralization quantity came from the release of the fixed ammonium. But because the proportion was small, the part of the fixed ammonium could be ignored.