Research On The Ecological Efficiency Of Cultivated Land Use In China Under The Dual Constraints Of Energy Use And Environmental Pollution

Cultivated land resource is the basic guarantee of national food security,which creates many values in economy,society and environment.After experiencing the refom and openness,with the development of agricultural science and technology,the growth of agricultural economy has acquired enormous progress,and the grain production capacity has improved significantly.To a certain extent,these achievements are achieved at the expense of resources and environment.The negative impact of cultivated land use on ecological environment is mainly manifested as "high input,high emission and high pollution".At present,the ecological environment protection of cultivated land use is facing the dual pressure of energy saving and environmental pollution control.In the face of these environmental problems,China mainly alleviates the environmental problems by controlling the amount of input.Although the input of chemical fertilizer and pesticide has been controlled to a certain extent,the direct energy such as raw coal,diesel oil and electric power in cultivated land production has continued to rise.It can be seen that China is still a petrochemical energy dependent agriculture,and still faces the contradiction between the growth of cultivated land production capacity and the protection of ecological environment Contradictions.If the reduction of cultivated land production will affect food security,and how to ensure the growth of cultivated land output under the goal of saving energy input and reducing environmental pollution?Improving the ecological efficiency of cultivated land use is the key to achieving the green growth of farming.Under the dual constraints of energy use and environmental pollution,what is the level of ecological efficiency of arable land utilization? What are the differences between the ecological efficiency of cultivated land use in different regions? What are the factors that affect the ecological efficiency of cultivated land use? How to effectively improve the ecological efficiency of cultivated land use in China? These problems are the key problems to be solved in the current research.Using 30 provinces of China between 1997 and 2018 as research units,based on the accounting of cultivated land energy utilization and environmental undesirable output,this article adopts the SBM model considering unexpected production to measure the cultivated land use ecological efficiency under the dual constraints of energy use and environmental pollution in China and the region,and uses the kernel density function and spatial autocorrelation method to analyze the dynamic of cultivated land use ecological efficiency in China and the region.The convergence of ecological efficiency of cultivated land use is analyzed by σ convergence and β absolute convergence.Finally,the dynamic panel model is used to analyze the factors affecting the ecological efficiency of cultivated land use.The main conclusions are as follows:(1)China’s total energy input of cultivated land rised from 22.5462 million tce in1997 to 43.6281 million tce in 2018,with the yearly rising rate of 3.2%;the total carbon emission of farmland use increased from 69.3902 million tons in 1997 to 99.1707 million tons in 2018,with the yearly rising rate of 1.7%;the total area-source pollution of farmland use increased from 394.05 cubic kilometers in 1997 to 513 million cubic kilometers in 2018 97 cubic kilometers,with the yearly rising rate of of 1.3%;(2)The ecological efficiency of cultivated land use in China decreased from 0.88 in 1997 to 0.68 in 2018,with an average annual growth rate of-1.2%,showing a "fluctuating decline" trend.Generally speaking,the ecological efficiency of cultivated land use in eastern,Western and central China was low from high to low from 1997 to2018,with the average values of 0.86,0.73 and 0.62 in eastern,Western and central China,respectively;the ecological efficiency of cultivated land use in non major grain producing areas was low The average value of land use efficiency was 0.76 and 0.73respectively;(3)From 1997 to 2018,the ecological efficiency of cultivated land use in each province is in a state of polarization,and the ecological efficiency of cultivated land use in most provinces is gradually decreasing.The average ecological efficiency of cultivated land use in Tianjin,Qinghai,Chongqing,Guizhou,Zhejiang,Sichuan and Shanghai is relatively high,while that in Anhui,Yunnan,Shanxi and Gansu is relatively low;(4)From the perspective of spatial differentiation,from 1997 to 2018,the ecological efficiency of cultivated land use in the eastern provinces was higher,but there was a downward trend in the internal provinces,and the low efficiency provinces gradually transferred from the central provinces to the western provinces.From the perspective of global autocorrelation,there is no spatial aggregation of cultivated land use efficiency in China from 1997 to 2018.From the perspective of local autocorrelation,from 1997 to 2018,the aggregation types of cultivated land use ecological efficiency in China are mainly "high high" and "low low" aggregation types.The eastern region has gradually changed from "high high" agglomeration to "high high" agglomeration and "low low" agglomeration.The central region is mainly of "high low" and "low high" aggregation types,while the western region has changed from "low low" aggregation type to "high low" aggregation type;(5)From 1997 to 2018,there is no σ convergence in most years of China,non major grain producing areas and western regions,while σ convergence in most years of major grain producing areas,Eastern and central regions.From 1997 to 2018,the ecological efficiency of cultivated land use in China,Eastern,central,western,major grain producing areas and non major grain producing areas showed β absolute convergence.The internal differences of cultivated land use ecological efficiency in China and other regions are gradually less.(6)From the perspective of influencing factors.Within the 10% statistical level,the significant influencing factors of cultivated land use ecological efficiency are urbanization level,cultivated land quality level,planting industry development level,human capital level and the lag of cultivated land use ecological efficiency.The first period of the lag term of the utilization ecological efficiency of cultivated land has a significant positive impact on the ecological efficiency of cultivated land use,which indicates that the improvement of ecological efficiency of cultivated land sometimes lags.Among the influencing factors,the level of urbanization and the quality of cultivated land have a significant positive impact on the ecological efficiency of cultivated land use,while the development level of planting industry and the level of human capital have a significant negative impact on the ecological efficiency of cultivated land use.Based on the above research conclusions,the following countermeasures and suggestions are put forward.(1)We should change the control center of farmland production and investment,realize the dual drive of reducing fertilizer and pesticide and transforming farmland energy consumption,and promote the use of renewable green and clean energy in farmland.(2)We should strengthen the coordinated development among regions and improve the ecological level of cultivated land utilization according to local conditions.(3)We should strengthen the prevention and control of environmental pollution,establish a long-term mechanism of cultivated land utilization and ecological environment protection.(4)We should strengthen the protection of cultivated land quality and consolidate the foundation of food security.(5)We should give full play to the beneficial role of feedback in the development of urbanization.(6)We should cultivate modern cultivated land use talents and improve farmers’ professional skills.