Integrating agriculture into China's mitigation policies.

Summary This thesis is an assessment of the overall technical and economic mitigation potential in Chinese agriculture and the conditions necessary for the formation of a carbon price in this sector. The scope of the research includes emissions from croplands and in particular those related to the use of synthetic nitrogen fertilizers. It is based on the construction of a marginal abatement cost curve (MACC), which provides a rational framework for combining biophysical and economic data to reflect mitigation costs. This tool aggregates the mitigation potential from applying a subset of cost-effective measures above a designated baseline. An analysis of China's climate policies reveals that agriculture is almost absent from the national mitigation strategy. We therefore intend to examine the feasibility, from a technical, economic and political perspective, of integrating agriculture into domestic mitigation policies. First, the trend and methods of calculating emissions are assessed to determine a rigorous approach to constructing baseline scenarios from business-as-usual projections for 2020. Second, we identify nine mitigation measures for cultivated soils, assess their abatement rates and future applicability beyond the baseline scenario to obtain a total technically feasible mitigation potential. Their translation into economic potential is then made by comparing the implementation costs of different mitigation options relative to conventional agricultural practices. The MACC results show that agriculture offers a significant mitigation potential, which could offset about one third of the baseline emissions and of which one third could be achieved at negative cost to farmers. Finally, we examine the use of economic instruments to reduce emissions at least cost in the agricultural sector. Given the institutional, behavioral, and social barriers, we strongly suggest reforming the fertilizer subsidy system to send a clear policy signal to farmers. The use of carbon intensity as a standardized benchmark is recommended to improve and broaden access to offset projects, and may also set the stage for a possible experimental emissions trading program in agriculture. Consistent with the priority of protecting food security in China, case studies of regional grain production are introduced in all these steps, including analysis of the greenhouse gas intensity of production in each province, the regional potential for reducing emissions from nitrogen fertilizer use, as well as the disparity in implementation costs in some regions.