北天山泥火山区CH4排放通量及其对大气的贡献率

CH4 is an important greenhouse gas, however the emission flux of geologic CH4 has been rarely studied. CH4 emitted from mud volcano areas takes up an important part of the geologic CH4. Four active mud volcanoes were found in the North Tianshan, China, from which the concentration of CH4 in the emitted gas ranged from 86.56% to 97.11%（Vol%）, but the CH4 flux is poorly understood. The emitted CH4 from Anjihai, Dushanzi, Baiyanggou and Aiqigou mud volcano areas is chosen as the resaerch object. Using digital bubble/liquid flowmeter, closed-chamber and gas chromatography to measure the flux (both macroseepage and microseepage) of CH4 emitted from the volcano areas. Meanwhile, the quantity of the CH4 emitted in the different ways from the mud volcano areas in the North Tianshan and their contribution to atmospheric CH4 will be studied. The conduction of the project will provide new data for estimating the contribution of the geologic CH4 emission to the atmosphere.

CH4是重要的温室气体，但地质源CH4排放通量的研究较少。泥火山是大气圈CH4的主要地质源之一，中国北天山地区发现四处活跃泥火山群，喷发气中CH4含量达86.56%～97.11%（Vol%），然而其CH4排放通量的报道罕见。本项目以北天山安集海、独山子、白杨沟及艾其沟泥火山区排放的CH4为研究对象，利用数字皂膜流量计、通量箱和气象色谱仪，测量北天山泥火山区CH4的宏观排放通量、微观渗漏通量及排放总量，进而揭示北天山泥火山区CH4排放的主要方式及对大气的贡献率，研究成果将为估算地质源CH4释放对大气的贡献率提供新的数据。

本项目以北天山安集海、独山子、白杨沟及艾其沟泥火山区排放的CH4和CO2为研究对象，利用数字皂膜流量计、通量箱和气象色谱仪，对北天山泥火山区CH4和CO2的宏观排放通量、微观渗漏通量进行了野外原位观测，揭示了北天山泥火山区CH4和CO2排放的主要方式及对大气的贡献率。研究成果表明，宏观排放为北天山泥火山区CH4和CO2排放的主要方式，北天山四个泥火山区CH4和CO2的年排放总量为8022.5t，研究成果为估算地质源温室气体释放对大气的贡献率提供了重要数据。