Study On The Synergistic Development Between Food Security And Agricultural Carbon Sequestration And Emission Reduction Under The ’Dual Carbon’ Framework In China

The people are the foundation of a country;food is the primary need of the people.Grain is crucial to national prosperity and people’s wellbeing.With the continuous improvement of residents’ living standards and consumption structure,China’s grain supply and demand have long been in a delicate balance.However,the high-input,high-consumption,and high-pollution model of grain production implemented in China has had a profound impact on global climate change,exacerbating the complexity and uncertainty of enhancements to its overall grain production capacity.The situation of food security and agricultural carbon sequestration and emission reduction is not optimistic.To cope with the adverse effects of global climate change,grain production,which has carbon source and sequestration functions,plays a vital role as the world’s largest emitter of agricultural greenhouse gases in accelerating comprehensive green transformation and achieving low-carbon agricultural development.Currently,China is in a period of agricultural modernization and low-carbon transformation with a focus on achieving agricultural carbon sequestration and emission reduction while ensuring national food security.China not only ensures national food security and an effective supply of important agricultural products but also faces the challenge of a potential slowdown in food production efficiency due to reduced carbon emissions.Therefore,in the context of increasingly severe global warming,scientifically evaluating China’s food security situation,clarifying the factors affecting the efficiency of the grain production environment,and exploring strategies for the synergistic development of food security and agricultural carbon sequestration and emission reduction are urgently needed to promote the harmonious progress of agricultural development and the ecological environment and achieve carbon peak and neutrality goals.This study delves into the interconnection and synergistic development strategies between food security and agricultural carbon sequestration and emission reduction in China against the backdrop of "dual carbon".The following research is mainly carried out in detail around four aspects:(1)A comprehensive evaluation of food security in China and its obstacle factors.This study developed a new framework for food security evaluation in China by analyzing its availability,distribution,utilization,vulnerability,sustainability,and regulation.The entropy weight-extension material element model and obstacle degree model were combined to empirically examine the development situation of China’s food security and conduct forward-looking risk identification of new contradictions and challenges in the field of food security.(2)Systematic modeling and measurement of the synergy between food security and agricultural carbon sequestration and emission reduction in China.Based on the carbon source coefficient method,the net carbon sequestration situation in provincial grain production in China was systematically calculated and explored from the perspectives of carbon absorption and emission balance.The spatial evolution and transfer paths of carbon sequestration intensity in provincial grain production in China were further predicted and evaluated using spatial statistical methods such as centroidstandard deviation ellipses and the spatial Markov chain.Based on this,a time-series coupled coordination degree correction model was used to evaluate and predict the synergistic effects of food security and agricultural carbon sequestration and emission reduction in China.(3)Measurement of environmental efficiency in grain production in China and analysis of its influencing factors.An efficient slack based measure(SBM)model considering unexpected outputs was established to measure the environmental efficiency of grain production,and the key driving factors of environmental efficiency in grain production in China were identified by combining the expandable stochastic environmental impact assessment model(STIRPAT)and the random forest(RF)algorithm of machine learning.Additionally,an economic geographical nested spatial weight matrix was used to construct a spatial econometric model to capture the factors influencing environmental efficiency on grain production in China from the perspective of the three major grain-producing functional zones.(4)Optimization of synergistic development policies for food security and agricultural carbon sequestration and emission reduction in China.A theoretical framework for the synergistic development of food security and agricultural carbon sequestration and emission reduction in China was constructed considering four aspects:the population subsystem,economic subsystem,resource subsystem,and environmental subsystem.A system dynamics model was used to observe and compare the levels of synergistic development of food security and agricultural carbon sequestration and emission reduction in China under different policy scenarios.Effective low-carbon agricultural sustainable development policies and action plans were formulated for the future situation and characteristics as appropriate for the local conditions.The main conclusions are as follows:(1)A comprehensive evaluation of China’s food security status from 2002 to 2021 was conducted using a matter-element extension model,and the research results indicated that China’s overall food security improved greatly but experienced a slight downward trend in 2003 and 2018.The main obstacles initially entailed grain distribution but then spread to vulnerability-and sustainability-related issues.In China,a populous country with few resources,issues related to resources and the environment have become a bottleneck restricting the sustainability and stability of food security.Over the past two decades,the key factors restricting China’s food security were the amount of fertilizer applied per unit of sown area and the grain self-sufficiency rate.The long-term use of pesticides and chemical fertilizers has significantly constrained the potential of China’s agricultural carbon sequestration and emission reduction.With a high degree of external dependence on soybeans and the prominent structural contradictions in grain,there are several hidden threats to China’s food security.Various unresolved issues,such as the need for improvement in the synergistic mechanism of food security factors,require our attention.(2)China’s agricultural carbon reduction efforts have achieved significant results.Throughout the entire sample period,the net carbon sequestration of grain production in China fluctuated greatly,with the overall trend of carbon emissions showing a fluctuating upward trend,but the growth rate gradually slowed.In terms of the carbon emission structure,China’s grain production carbon emissions have remained relatively stable,mainly due to rice cultivation and agricultural inputs,with soil nitrification and agricultural land use carbon emissions as supplementary sources.From a spatial perspective,the center of gravity of carbon sequestration intensity in China’s grain production has shifted toward the northeast within Linfen city,Shanxi Province,displaying a relatively concentrated spatial distribution overall and presenting a spatial pattern of "northeast-southwest".There are significant differences among the provinces,with high carbon sequestration intensity regions mainly concentrated in major grain-producing provinces.(3)There is a "Matthew effect" and "club convergence" phenomenon in the carbon sequestration intensity of grain production in China.Most provinces show a strong "inertia" in terms of the carbon sequestration intensity of grain production,and the skip transfer paths across levels are blocked and can be transferred only to adjacent types.After considering the spatial effects of neighboring provinces,the neighborhood level weakens the path dependence of carbon sequestration intensity development and enhances the activity of carbon sequestration intensity level transfer in grain production across provinces.In addition,low-level neighborhoods can hinder the development of carbon sequestration intensity in provinces and even lower carbon sequestration intensity levels,whereas high-level neighborhoods play a positive role in promoting the development of carbon sequestration intensity in provinces.The long-term trend of carbon sequestration intensity in provincial grain production in China is relatively optimistic,gradually forming a "skewed peak" distribution of high-level clustering over time and showing an overall gradual upward trend.The synergy between food security and agricultural carbon sequestration and emission reduction has shifted from dissonance and decline to overall coordination,but further improvement toward highquality coordination is needed.The spatial distribution generally shows an overall trend pattern along the "Hu Line",with high values in the northwest and low values in the southeast.(4)The environmental efficiency on grain production in China has a significant positive spatial correlation,and local clustering has occurred.By incorporating economic and geographical factors into a spatial econometric model to compare the regression results of the three major grain-producing functional zones,it was found that there are significant differences in the degree of influence of different factors within each functional zone.For the main grain-producing zones,the amount of rural agricultural labor force,income level,and research and development intensity have a significant positive impact on the environmental efficiency of grain production,while human capital,industrial structure,and urbanization level have negative impacts on the environmental efficiency of grain production.For the main grain-consuming zones,innovation promotes the improvement in environmental efficiency in grain production,while the scale of the rural agricultural labor force hinders them.For the production and consumption balance zones,the development of human capital,the amount of agricultural production labor force,income level,innovation,and industrial structure promote improvements in production environmental efficiency,but capital stock limits improvements in food production environment efficiency to some extent.(5)There are complex interactions and feedback relationships among the elements composing the synergistic development system of food security and agricultural carbon sequestration and emission reduction in China;population,economy,resources,and environment are the core elements of this system.In the process of economic and social development,China is facing the problems of excessive resource pressure and serious environmental pollution.Prioritizing the enhancement of economic and social benefits at the expense of resources,even exceeding the carrying capacity of the resources and environment,is not a sustainable long-term effective approach.Multiscenario simulations revealed that compared to models using the benchmark scenario,economic growth-dominated scenario,technological progress-dominated scenario,and resource and environment-constrained scenario,the sustainable development model in which coordination of economic growth,improvement in residents’ wellbeing,resource consumption,and environmental protection advance together under the coordinated development scenario constitute the optimal path for the sustainable improvement in the synergistic development level of China’s food security and agricultural carbon sequestration and emission reduction.(6)To achieve a win-win situation of food security and agricultural carbon sequestration and emission reduction in China while strictly adhering to the red lines and bottom lines of resource elements and improving the compensation mechanism for ecological environment protection,we need to accelerate low-carbon agricultural technology,strengthen the promotion and service of scientific research achievements,give full play to the guiding function of agricultural subsidy policies,enhance the lowcarbon agricultural production system,develop differentiated low-carbon agricultural development models,promote cross-regional exchanges and cooperation,and drive the development of agriculture toward a more green,healthy,and sustainable direction.