菹草腐烂分解过程中污染物的动态释放

发布时间：2018-04-25 12:37

本文选题：菹草 + 腐烂分解　；参考：《干旱区资源与环境》2017年08期

【摘要】：采用分解袋法,对典型沉水植物菹草进行了连续100天的室外腐烂分解试验,分析了菹草干物质的损失及营养元素释放的动态变化规律。结果表明:在100天的分解实验中,菹草干物质量急剧减少,且表现为前期损失快,后期损失减缓的趋势,第100天时,菹草干物质质量损失了92.51%,残留率为7.49%。采用Olson指数模型菹草枯落物干物质的动态变化,计算其分解速率常数(k)为0.028g/d,分解50%干物质所需时间为24.47天,分解95%干物质量所需时间为105.57d,年残留率为0,表明菹草枯落物在一年内能彻底分解。植物枯落物中氮磷含量随着分解时间的延长而呈波动变动,但氮磷营养元素的损失与干重的损失速率并不同步。分解初期氮含量上升,随后呈下降-上升的变化趋势,而磷含量总体呈现波动下降趋势。试验结束后,氮、磷元素分别释放了9.14%、32.02%。此外,菹草枯落物氮、磷元素积累指数(NAI)平均值分别为46.10和32.23,表明菹草在腐烂分解过程中,氮磷元素均以净释放为主。
[Abstract]:The decomposition bag method was used to decompose the typical submerged plant Potamogpus crispus for 100 days, and the dynamic changes of dry matter loss and nutrient release of Potamogpus crispus were analyzed. The results showed that in the 100-day decomposition experiment, the dry weight of P. crispus decreased sharply, and showed the tendency of quick loss in the early stage and slow down in the later stage. On the 100th day, the dry matter loss of P. crispus was 92.51%, and the residual rate was 7.49%. The dynamic changes of dry matter in litter of P. crispus were calculated by using Olson index model. The decomposition rate constant (K) was 0.028 g / d, and the time to decompose 50% dry matter was 24.47 days. The decomposition time of 95% dry matter was 105.57 days and the annual residue rate was 0, which indicated that the litter of P. crispus could be completely decomposed within one year. The content of nitrogen and phosphorus in plant litter changed with the prolongation of decomposition time, but the loss of nitrogen and phosphorus was not synchronized with the loss rate of dry weight. At the beginning of decomposition, the nitrogen content increased, then decreased and increased, while the total phosphorus content fluctuated and decreased. At the end of the experiment, nitrogen and phosphorus released 9.14% and 32.02% respectively. In addition, the average values of nitrogen and phosphorus accumulation index in litter of P. crispus were 46.10 and 32.23, respectively, indicating that the net release of nitrogen and phosphorus was dominant in decomposition of P. crispus.
【作者单位】：江苏大学环境与安全工程学院;
【基金】：江苏省水利科技项目(2016050) 江苏省大学生创新创业训练计划项目(201610299059Y)资助
【分类号】：X173

【相似文献】