Nitrous oxide emissions from the surface of the Three Gorges Reservoir

详细信息    查看全文

• 作者：Dan Zhu ; Huai Chen ; Xingzhong Yuan ; Ning Wu ; Yongheng Gao ; Yan Wu ; Yongmei Zhang ; Changhui Peng ; Qiu鈥檃n Zhu ; Gang Yang ; Jianghua Wu
• 关键词：N2O emission ; Nitrogen loading ; Climate change ; Hydroelectric dams
• 刊名：Ecological Engineering
• 出版年：November, 2013
• 年：2013
• 卷：60
• 期：Complete
• 页码：150-154
• 全文大小：793 K

文摘

Nitrous oxide (N₂O) emissions from the surface of the Three Gorges Reservoir (TGR), one of the largest dams worldwide, have not been well monitored before. This study measured N₂O emissions from the surface of the TGR at seven sites from February to December 2009. The measurement found no significant spatial variation of N₂O emission from the reservoir, but significant seasonal variation, with the contribution of N₂O emission in warm season accounting for 86% of the total, and that in June significantly higher than the other times (P < 0.001). Furthermore, N₂O fluxes were found to be significantly correlated with water surface temperature (T) and total nitrogen in water column (N) (F = 0.002 T + 0.017 N 鈭?#xA0;0.035, R = 0.39, P_T < 0.001, P_N < 0.01, n = 42). The overall annual N₂O flux rate (mean 卤 SD) was 0.014 卤 0.021 mg N₂O m^鈭? h^鈭?, relatively low compared with those from other reservoirs. We also found low N₂O emission rate from downstream immediately after the dam (0.010 卤 0.009 mg N₂O m^鈭? h^鈭?). Such a low N₂O flux from TGR should be attributable to the low nitrogen (N) loading in the water body, which is the result of multiple approaches taken to maintain water quality and protect environment to decrease the input of N.