Reducing emissions and sequestering carbon in agriculture is an important part of achieving the goal of carbon peak and carbon neutrality. The development of new quality productivity is a powerful measure to promote agricultural emission reduction and carbon sequestration. A study participated by the author showed that biochar as a new productivity category is expected to become a key technology for carbon emission reduction and sequestration in green organic rice fields.
The application of biochar can promote the reduction of carbon sequestration in agriculture
From 2022 to 2023, the Nanjing Institute of Environmental Sciences of the Ministry of Ecology and Environment, together with Nanjing Agricultural University and Nanjing Guohuan Organic Product Certification Center, set up a research team to adhere to scientific and technological innovation, build a 500-mu organic rice planting demonstration base in Dongba Street, Gaochun District, Nanjing City, Jiangsu Province, and carry out research on the application of biochar to promote farmland emission reduction and carbon sequestration. The author believes that biochar has achieved remarkable results in reducing agricultural carbon emissions and sequestration, which is mainly reflected in the following three aspects:
First, biochar can effectively reduce emissions and increase sinks in paddy fields. The soil organic matter content of paddy fields using biochar increased by an average of 4%;4Emissions reduced by 16%, N2O emissions were reduced by 23 per cent, total greenhouse gas emissions were reduced by 16 per cent, soil carbon sequestration increased by an average of 89 per cent, and net greenhouse gas emissions were reduced by an average of 51 per cent.
Second, biochar can effectively reduce the occurrence of pests and diseases. Compared with the surrounding organic paddy fields, the incidence of sheath blight and the incidence of dimorphic borer insect pests were reduced by about 20% and the incidence of borer pests in the demonstration base was reduced by about 15%.
Third, biochar can promote the realization of the value of agricultural carbon sinks. Biochar was applied to 500 acres of organic paddy fields, and the farmland carbon sink reached 130.67 tons of CO2In 2024, with the support of the Gaochun District Government, the first agricultural carbon sink transaction in Jiangsu Province will be completed, bringing nearly 10,000 yuan of "air sales" income to the village collective.
Promote the realization of the value of agricultural carbon sinks and improve the effectiveness of agricultural emission reduction
At present, agricultural carbon sink trading is still a blank spot in the national greenhouse gas voluntary emission reduction trading market. The development of new quality productivity to promote the realization of the value of agricultural carbon sinks is to strengthen the practical innovation of economic means to protect the ecological environment.
The first is to strengthen policy support for agricultural emission reduction and increase of foreign exchange. At present, China has implemented a carbon emission trading system in the field of industrial energy, the connection between carbon trading and agriculture is insufficient, and governments at all levels lack guidance and incentives for measures conducive to farmland emission reduction and sink increase such as conservation tillage and organic planting, which restricts the development and promotion of farmland emission reduction and sink increase projects to a certain extent. It is suggested to accelerate the construction of a policy support system for agricultural carbon emission reduction and carbon sequestration, establish a positive incentive and negative constraint mechanism, improve the value of agricultural carbon emission reduction and agricultural carbon sinks, and explore the establishment of an ecological protection compensation mechanism that reflects the value of agricultural carbon sinks.
The second is to improve the research on the measurement methodology of agricultural emission reduction and increase of sinks. The establishment and operation of the agricultural carbon sequestration trading market first needs to improve the relevant methodology. Up to now, no methodology for reducing emissions and increasing sinks in agriculture has been published. It is suggested that relevant departments should refer to the Administrative Measures for Voluntary Greenhouse Gas Emission Reduction Trading (Trial) to accelerate the formulation of the development and operation procedures for voluntary emission reduction agricultural carbon sink projects, and guide and encourage universities, research institutions, enterprises and institutions, industry associations, etc. to independently develop and compile agricultural carbon sink project methodologies. Through pilot implementation, explore and summarize the formation of an agricultural carbon sink technical standard system, a measurement and monitoring system and a comprehensive service system.
The third is to promote the industrialization of straw carbonization. At this stage, there are few domestic biochar manufacturing enterprises, and the long-distance transportation of raw materials and finished products has led to high terminal sales prices, which limits the promotion and application of biochar. The production technology threshold of biochar is low, the raw materials are sufficient, and the basic investment is controllable. It is suggested that relevant departments should organize and carry out research on the industrialization of biochar, promote the large-scale application of biochar in farmland by improving biochar production capacity and reducing terminal costs, and simultaneously solve the problems of straw disposal, air pollution by incineration, and high incidence of pests and diseases caused by direct return to the field.
Fourth, innovate new scenarios for the development of agricultural carbon sequestration and emission reduction carbon sinks. Adhere to the green development, digital development and sustainable development of agriculture, expand the development and application scenarios of emission reduction and carbon sequestration technologies, vigorously develop resource-saving circular agriculture, advocate the use of scientific agricultural and veterinary drugs, promote fertilizer saving and efficiency, implement pesticide reduction actions, build green carbon sink fruit and tea gardens, enhance the carbon sequestration capacity of crops, and continue to promote healthy and low-carbon livestock and poultry breeding. Improve the level of agricultural waste recycling and resource utilization, improve the efficiency of agricultural waste treatment centers, recycle agricultural wastes as organic fertilizers after fermentation, and promote agriculture to enhance the ability of "carbon sequestration and oxygen release".
Author Affilications:Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment