Generic information about the conflict: China is a great agricultural country, and there are about 700 million tons of crop straws out of production, of which there are 400 million tons of crop straws that can be used in energy development. However, in recent years, with the development of socialist new rural construction and urbanization, the improvement of energy consumption structure and the application of various alternative raw materials, coupled with the high cost of comprehensive utilization of straw, poor economy and low degree of industrialization, it has begun to appear regional, seasonal, and structural surplus of straw, especially in the main grain producing areas and parts of the coastal economically developed areas, the phenomenon of open burning has been repeatedly banned, which wastes resources, pollutes the environment, and threatens traffic safety.
Conflict type: Over a long period, crop straws are main living fuels, livestock and poultry feed and organic fertilizers of rural residents in China, and a small part is used as industrial papermaking raw material. However the abuse of crop straws have caused severe problems to environment. So the conflicts is between environment and crop straws of biogas plants.
Resources involved: crop straws, mainly contain rice, wheat and corn straw.
Evaluation of the conflict：
China is one of the largest agricultural countries in the world, and before the 1970s, the crop straw was mainly used as a fuel source for household and fodder for domestic animals. Due to the low straw yield per unit, the production of crop straw was consequently limited. Since the 1980s, with the increase of crop yield, the total amount of crop straw has increased rapidly, while the proportion of the straw as a fuel source for household and fodder for domestic animals has apparently decreased. This is due to the fact that farmers want to remove the straws from fields quickly and save the cost of transportation and the storage of the straws, and therefore in most regions as a normal practice the crop straws are burnt in fields after harvest. The field burning of crop straw in wide areas not only results in serious environmental issues, affects air visibility, but also wastes the precious biological resources. The field burning of crop straws has already become the social and environmental problem in China and has been concerned by public communities. Chinese government has banned the field burning of crop straws and has even applied satellite technology to monitor the open burning in rural areas, but the effect is far from satisfactory.With the emission factors from literature and experiments, appropriate emission factors have been obtained. The total amounts of PM, SO2, NOx, NH3, CH4, BC, OC, VOC, CO, CO2 emissions from field burning of crop straw in China are estimated.
In China, field burning of crop straw is mainly practised in the following regions: (1) grain-producing regions with a small population density, such as Jilin and Heilongjing, where the massive surplus crop straw cannot be comprehensively burnt; (2) developed regions like Shanghai, Zhejiang and Jiangsu, where crop straw used as a major fuel source have been gradually replaced by commercial energy; and (3) energy producing regions, including Shanxi and Shaanxi, where the farmers have easy access to cheap energy sources, leaving massive crop straw surplus.
The amount of field-burning crop straw is determined by climatic zone, rural living level, vegetation coverage and main output of crops for each district. However,there are no statistic data for this and few studies had been done. Limited data show that approximately 27.2% of crop straw was burnt in 1995 and 15.2% in 1998. More detailed studies indicate that 33% of the crop straw was burnt in 1998 in Jiangsu Province, while the figures were 32.4% for Guangdong Province, 50%―60% for Fuzhou city in 2001, 39.6% for Shanghai in 2000, respectively.
Straw contains a lot of organic matter, nitrogen, phosphorus, potassium and trace elements. Straw biogas technology is used to decompose straw to produce biogas and biogas residue, which not only effectively utilizes crop straw, but also solves the problem of lack of fermented raw materials for biogas projects using livestock and poultry manure as raw materials. The idle problem has broken the dependence of biogas construction on livestock and poultry farming. In particular, the centralized gas supply technology with straw as the main raw material, the construction of anaerobic digestion equipment and gas storage equipment in the natural village, the biogas is transported to the farmers' homes through the pipe network, solving the problem. At the same time, the process of collecting, storing and transporting crop straw resources has increased direct employment opportunities for local farmers. The sale of straw increases the income of farmers and turns waste into treasures from farmers who are still farmers. Therefore, the research and development and promotion of straw biogas technology can achieve multiple effects such as energy recovery, material recycling, environmental protection, and increase farmers' income.
Main elements that may preclude conflict resolution：
(1) Straw biogas technology is in its infancy
At present, domestic research on straw biogas technology is infancy, and the completed straw biogas project has been in operation for less than 3 years. It has not been identified by provincial and ministerial-level scientific and technological departments. There are also some technical, economic and management problems, and it needs to be tested by practice.
(2) Straw biogas project has lower self-financing ability
Compared with the livestock manure biogas project, since the straw biogas project increases the collection, storage and treatment of raw materials, it is necessary to increase facilities and equipment, such as fire-fighting facilities, so that the one-time investment in civil works and equipment is higher; the source stability of straw raw materials affected by the season, straw directly purchased from farmers leads to poor price control, and engineering energy consumption and other factors lead to higher operating costs; China's straw biogas project mainly focuses on gas supply, and the saleable products are biogas and biogas residue, biogas welfare is sold to the villagers as an anecdote, and the biogas residue can be made into organic fertilizer. However, since the farmers have not fully accepted the biogas residue, they are basically provided to the villagers for free, plus the CDM mechanism. Not introduced, the benefits of biogas projects are not high. The project investment, high operating costs, and low product income have resulted in poor self-financing ability of the straw biogas project.
(3) Less policies to support the operation of straw biogas projects
In recent years, the Party Central Committee and the State Council have attached great importance to the construction of rural biogas, especially since 2008, which has increased support for straw biogas. The central investment funds are mainly used to support the construction of straw biogas projects, including civil engineering and equipment investment. There are few policies and incentive mechanisms for the later operation of the project and end products. It is difficult to mobilize the enthusiasm of the owners solely by the market profit of biogas engineering products. Therefore, there are biogas projects that are not operating at full capacity or even stopped.
Main elements that may encourage conflict escalation ：
The straw biogas project can make full use of rural straw resources, improve the rural environment, and provide high-quality clean energy for rural residents. It is receiving extensive attention throughout the country. China's straw biogas project will be developed in the direction of standardization and scale with the strong support of the central government. The development trend will be reflected in the following aspects.
(1) The raw materials of the biogas project will be converted from livestock manure to diversified materials with straw as the main raw material. In order to ensure the stable source of raw materials for straw biogas projects, it is bound to add alternative raw materials such as domestic garbage and manure, in order to overcome the shortcomings of straw raw materials being affected by seasonality and price uncontrollability.
(2) The construction site of the straw biogas project will be expanded from rural areas to urban integration areas. The development of rural urbanization in China has increased the demand for energy. Facing the shortage of energy, the construction of waste recycling project with straw biogas as the core in the urban-rural integration will improve the urban and rural environment and develop a circular economy and implement renewable An important part of the energy development strategy.
(3) Pay more attention to high-efficiency, high-value and comprehensive utilization of straw biogas engineering products. Due to the energy shortage in the world, the high value-added development and utilization of biogas will be the future development trend. In view of the current difficulties in the elimination of biogas slurry and seasonality, the development of biogas slurry in the cultivation and aquaculture industry. The comprehensive use of ecological models is also the focus of development.
(4) The operation and management mode of straw biogas project will develop in the direction of specialization. The key to the sustainable development of the straw biogas project is the operation management mechanism. Entrusting the professional biogas company to standardize the operation and management of the biogas project, and introducing the CDM mechanism to increase the efficiency of the biogas project will be the future development direction.
Keywords and identifiers of the conflict：
Biogas plants, crop straws, China energy, environment
The status and trends of the development of biogas plants for crop straws in China. Available at:http://www.biogas.cn/UpLoadEditor/file/20150305/20150305102017_2105.pdf
 Estimation of emissions from field burning of crop straw in China. Available at: https://link.springer.com/article/10.1007/s11434-008-0145-4