Methane and nitrous oxide in natural waters/ metano y óxido nitroso en aguas naturales

Resumen

The South China Sea (SCS) is the largest marginal sea in the world. Historically, the seas have buffered the greenhouse effect by acting as a sink of atmospheric CO2. There is increasing evidence that this has slowed and that some tropical seas, such as the SCS, are now a small source of CO2 to the atmosphere. Moreover, methane (CH4) and nitrous oxide (N2O) are clearly much more supersaturated in the SCS. Since marginal seas represent a large percentage of coastal regions and are strongly affected by anthropogenic activities, the situation in marginal seas may have become more severe in comparison to other sea areas. More importantly, as terrestrial input increases and coastal areas under hypoxia expand, more CH4 and N2O may be emitted. According to the research we have done in the SCS, this thesis includes a preliminary assessment of the Greenhouse effect which is caused by CH4 and N2O emission in the SCS. In addition, using the social-environmental frameworks (Driver-Pressure-State-Impact-Response (DPSIR) framework and the Systems Approach Framework (SAF)) to analyze the issue and then respond to policies and management measures. This has major policy implications, in the context of the Conference of Parties (COP) of the United Nations Framework Convention on Climate Change (UNFCCC). In dealing with the complex issues of greenhouse gas emission and climate change mitigation, many interrelated factors exist, such as cost, level of technology development, and expenditures on research and development. However, the SCS remains one of the most disputed maritime areas of the world. While countries are trying to consolidate their sovereign claims, they still share a desire to sustain a peaceful regional environment to promote a prosperous economic development. By framing internationalized environmental protection, climate change mitigation and adaption, not only maintain the environmental sustainability and food security, but also provide an international cooperative platform for all the SCS surrounding countries.