于黄河第9次调水调沙期间在黄河下游垦利站开展调查,分析了调水调沙对黄河溶存甲烷浓度分布及黄河甲烷年入海通量的影响.于2009年6～7月黄河调水调沙前、中、后期对黄河口及邻近海域开展调查,探讨了调水调沙对黄河口甲烷分布的影响.结果表明:调水调沙期间黄河垦利站甲烷浓度变化范围为9.89～205.34nmol/L,与径流量和悬沙含量呈正相关,表明甲烷主要来源于河床底层浮泥的释放.调水调沙期间黄河向渤海输送的甲烷约为2.2×105mol,约占2009年黄河向渤海输送甲烷总量的50％,调水调沙对甲烷输送通量在年内的分配有较大影响.黄河口及其邻近海域的三次调查结果显示甲烷浓度范围为3.71 ～37.77nmol/L,受黄河冲淡水影响较大.据估算黄河口甲烷的饱和度为(649.7±292.1)％,黄河口及其邻近海域是大气甲烷的净源.%Surveys were earned out at Kenli during the ninth water-sediment regulation to discuss its effect on distribution and fluxes of dissolved methane in the lower Yellow River. Three surveys were also carried out in the Yellow river estuary and adjacent area in June and July 2009. The water-sediment regulation had great effect on the distribution of the dissolved methane in the Yellow River estuary. Methane concentrations ranged from 9.89 to 205.34nmol/L at station Kenli, which correlated well with suspended sediment and water discharge, showing that dissolved methane in the waters mainly came from the release of fluid mud. Riverine input of CH4 to Bohai Sea was estimated to be about 2.2×105mol during the period of water-sediment regulation, which was about 50% of the total CH4 fluxes from the Yellow river in whole year. CH4 concentrations ranged from 3.71 to 37.77nmol/L in the Yellow River estuary and adjacent area in June and July 2009, which was mainly affected by freshwater plume. Surface waters of this area were over-saturated in methane with respect to atmosphere equilibrium (649.7±292.1)%, hence the Yellow River estuary and adjacent area was a major source of atmospheric methane.
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