| 江西香溪流域干湿季交替下底泥氮释放机制及其对流域氮输出的贡献 |
| 摘要点击 2375 全文点击 1123 投稿时间：2015-08-11 修订日期：2015-09-20 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 流域 氮输出 底泥 氮释放 干湿交替 |
| 英文关键词 watershed N export sediment N release wet and dry alternation |
| 作者 | 单位 | E-mail | | 韩宁 | 中国科学院地理科学与资源研究所, 生态系统网络观测与模拟重点实验室, 北京 100101 | 1293384193@qq.com | | 郝卓 | 中国科学院地理科学与资源研究所, 生态系统网络观测与模拟重点实验室, 北京 100101
西南大学资源环境学院, 重庆 400716 | | | 徐亚娟 | 中国科学院地理科学与资源研究所, 生态系统网络观测与模拟重点实验室, 北京 100101 | | | 高扬 | 中国科学院地理科学与资源研究所, 生态系统网络观测与模拟重点实验室, 北京 100101 | gaoyang@igsnrr.ac.cn | | 于贵瑞 | 中国科学院地理科学与资源研究所, 生态系统网络观测与模拟重点实验室, 北京 100101 | |
|
| 中文摘要 |
| 本研究通过对江西千烟洲香溪流域的氮输出进行长期监测,并对该流域内的底泥进行基于正交试验的氮释放规律模拟研究,评估干湿季节交替下底泥氮释放对流域氮输出的贡献. 结果表明:①流域底泥在静态下 TN释放速率最大值为 36 mg ·(m2 ·d)-1,且随着时间的延续释放速率不断变小; ②对底泥氮释放影响的主次顺序为:温度>扰动>pH,如将扰动视为误差项,温度和 pH对底泥氮释放的影响均为极显著; ③ TN释放速率与温度成正比例关系,随着温度升高,释放速率增大; 酸性和碱性条件均能促进底泥氮释放,且酸性条件的促进作用更强; ④流域底泥 TN和有效氮含量变化范围分别为: 414.7~899.6mg ·kg-1和 17.5~58.9 mg ·kg-1,有效氮占TN的质量分数为3%~10%; ⑤流域在旱季 TN输出浓度范围为 0.58~2.40mg ·L-1,在雨季 TN输出浓度范围为 1.73~4.87 mg ·L-1; 流域底泥的氮释放通量约为 106.34kg ·a-1,流域氮输出总量为 864.15 kg ·a-1,底泥的氮释放对流域水体氮输出的贡献率约为 12.31%,底泥氮释放对流域水体富营养化的贡献应引起重视. |
| 英文摘要 |
| In this study, N export from Xiangxi River Basin in Qianyanzhou station was measured by long-term monitoring, and simulation study on N release law from the sediment in watershed was carried out based on orthogonal experiment, and at last the contributions of N release from sediment to N transport from watershed under dry and rainy season alternation were estimated. The results showed that the maximum of TN release rate was 36 mg ·(m2 ·d)-1 in stable status, which decreased with increasing time; the impact of the three controlling factors on the N release followed the order of temperature > disturbance > pH, and the effect of temperature and pH on N release from the sediment was significant when disturbance was considered as the error term; TN release rate increased with increase of temperature, and acidic and alkaline conditions could also promote N release from sediment, wherein the effect of acidic conditions on N release was stronger; the changes of TN and available N content in sediment were 414.7-899.6 mg ·kg-1 and 17.5-58.9 mg ·kg-1, so the percentage of available N only accounted for 3%-10% of TN; the TN transport concentrations were 0.58-2.40 mg ·L-1 and 1.73-4.87 mg ·L-1 in dry and wet seasons, respectively, the N release flux from sediment was about 106.34 kg ·a-1, the total N transport from watershed was 864.15 kg ·a-1, and the contribution rate of N release from sediment to N transport from watershed was about 12.31%, so we should pay much attention to the contribution of N release from sediment to water eutrophication. |
|
|
|
