Hu Tao, Huang Jian, Ding Ying, Sun Zhi-Rong, Xu Meng-Fan, Liu Shu-Wei, Zou Jian-Wen, Wu Shuang
College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Jiangsu Collaborative Innovation Center for Solid Organic Waste Resources Utilization, Nanjing 210095, China.
Huan Jing Ke Xue. 2020 Feb 8;41(2):941-951. doi: 10.13227/j.hjkx.201905092.
Freshwater aquaculture ponds collectively cover a large area in southeast China. They are an important anthropogenic source of CH emissions, however current knowledge of CH emissions from aquaculture ponds is limited. During September 2017 and August 2018, two independent sampling campaigns of CH flux measurements over annual cycles were carried out in a fish-aquaculture pond in southeast China using a floating chamber and diffusion model methods for comparison. The purpose of this study is to investigate the variation of CH fluxes obtained from the fish-aquaculture pond, analyze the emission mechanisms, and amplify the CH emissions inventory. The diffusion model method can further quantify the contribution of diffusion transmission to CH emissions. The seasonal variations of CH fluxes measured by the two methods were similar, with higher CH fluxes appearing in summer and fall and lower CH fluxes appearing in spring and winter. CH fluxes measured by the floating chamber method and diffusion model method ranged from 0.14-3.13 mg·(m·h) and 0.04-1.41 mg·(m·h), respectively, and the respective average values were (0.86±0.30) mg·(m·h)and (0.45±0.08) mg·(m·h). The CH fluxes were positively related to water temperature, dissolved organic carbon (DOC) and chemical oxygen demand (COD), but negatively related to the water dissolved oxygen (DO) concentration in the fish-aquaculture pond. CH fluxes calculated by diffusion model methods were 45% lower than those determined by the floating chamber methods over annual cycles. The result suggested that the floating chamber method is more suitable than the diffusion model method for measurements of CH fluxes in freshwater aquaculture ecosystems.
淡水养殖池塘在中国东南部地区总面积较大。它们是甲烷（CH）排放的一个重要人为来源，然而目前关于养殖池塘甲烷排放的知识有限。在2017年9月至2018年8月期间，在中国东南部一个养鱼池塘进行了两次独立的年度甲烷通量测量采样活动，采用浮动箱法和扩散模型法进行比较。本研究的目的是调查养鱼池塘甲烷通量的变化，分析排放机制，并扩大甲烷排放清单。扩散模型法可以进一步量化扩散传输对甲烷排放的贡献。两种方法测量的甲烷通量季节变化相似，夏季和秋季甲烷通量较高，春季和冬季甲烷通量较低。浮动箱法和扩散模型法测量的甲烷通量分别为0.14 - 3.13毫克·（平方米·小时）和0.04 - 1.41毫克·（平方米·小时），各自的平均值分别为（0.86±0.30）毫克·（平方米·小时）和（0.45±0.08）毫克·（平方米·小时）。养鱼池塘中的甲烷通量与水温、溶解有机碳（DOC）和化学需氧量（COD）呈正相关，但与水体溶解氧（DO）浓度呈负相关。在年度周期内，扩散模型法计算的甲烷通量比浮动箱法测定的低45%。结果表明，在淡水养殖生态系统中，浮动箱法比扩散模型法更适合测量甲烷通量。
