1. Introduction
Since the industrial revolution, the economies of various countries have achieved rapid development. At the same time, environmental problems have become increasingly prominent, especially the continuous increase in greenhouse gas carbon emissions and global warming [
1], which have a serious impact on production and life. Rapid economic growth has accelerated carbon dioxide emissions, and the environmental and climate issues caused by carbon emissions have gradually attracted the attention of the international community. Countries around the world are also making active efforts to reduce carbon emissions and slow global warming [
2,
3].
China’s development model will definitely have a profound impact on the world. The balanced development of energy security issues, living environment issues, and economic development issues are problems and dilemmas faced by the government, constantly testing the wisdom of Chinese leaders. Against the dual background of energy shortages and climate deterioration, countries all over the world are rushing to change their development methods and pursue a new sustainable development model with low emissions [
4]. To achieve the difficult goal of controlling carbon emissions, China needs to reduce energy consumption. This path is full of difficulties, as it needs various industries across the country, such as manufacturing, energy, and foreign trade to make adjustments to reduce carbon emissions in concert [
5,
6].
Faced with the requirements of reducing carbon emissions, the logistics industry, as a high-carbon emission field, has assumed most of the responsibility for reducing carbon emissions. Based on the report by the International Climate Organization, the energy consumed by the transportation industry in 2006 accounted for more than 20% of the world’s energy consumption. The reason for the high carbon emissions of the transportation industry is its higher energy consumption; therefore, it needs effective measures to reduce energy consumption. The Chinese logistics industry is a long way from the international level and is in a period of rapid development. There is huge room for development in terms of the scale of development and technological improvements, which also provides the possibility of reducing carbon emissions across the country. At present, the development of regional logistics is still in the expansion stage, and the input–output structure and development scale are unreasonable. While the logistics has achieved rapid development, the logistics cost is relatively high. Especially with the rapid development of regional logistics, the environmental pollution caused by logistics activities is increasing. From the research on industry carbon emissions, compared with the decline in carbon emissions in agriculture, industry, construction, and other industries, the carbon emissions of the logistics industry have shown an upward trend, becoming one of the few companies whose carbon emissions continue to increase [
7]. However, due to differences in development level, system, and location factors, there are differences in logistics carbon emissions in different regions. In the context of vigorously carrying out energy conservation and emission reduction, reducing logistics carbon emissions and improving logistics operation efficiency are the key and focus of Chinese development of energy conservation and emission reduction, and also an important way to achieve China’s emission reduction goals [
8]. The main content is what is the status quo of regional logistics carbon emissions, whether the level of logistics carbon emissions in various regions is balanced, what are the factors that affect regional logistics carbon emissions, and how to formulate regional logistics carbon emissions control strategies based on the influencing factors.
The main significance of this study is, on the one hand, with the increasingly serious problems of energy crisis, climate warming and environmental deterioration, the sustainable development of economy has been paid more and more attention. As a major source of energy consumption and carbon emissions, logistics plays an important role in sustainable economic development. Reducing the carbon emission of logistics and promoting the low-carbon development of logistics are the objective requirements to improve the sustainable ability of logistics and are also an effective way to speed up the transformation of the economic development mode. On the other hand, the differences and influencing factors of regional logistics carbon emission levels are analyzed and studied, and a regional logistics carbon emission control strategy is given based on the influencing factors, which provides reference for the control of regional logistics carbon emissions and the formulation of carbon emission reduction policies and is helpful for improving regional logistics. The level of sustainable development of logistics is of strategic significance.
Therefore, based on the LMDI decomposition method, this paper decomposed the carbon emission factors of China’s regional logistics industry from 2010 to 2020, found out the main driving factors of regional logistics industry carbon emissions and determined their degree of effect, and then, studied the decoupling effect of regional carbon emissions. The influence of influencing factors on the carbon emissions of logistics in different regions was obtained, and the decoupling of logistics carbon emissions in different regions was analyzed at the same time. The main research framework of this paper is as follows: The second part is a literature review, which mainly analyzes the main contributions of existing research in this field and hopes to provide theoretical reference for this research. The third part is the method introduction, which mainly explains the rationality of the methods used in this paper. The fourth part is the empirical analysis results and discussion, focusing on the contribution of the results obtained. The last part is the conclusions and shortcomings of this study.
3. Material and Methods
3.1. Measuring Carbon Emissions
The commonly used methods for measuring carbon emissions include the actual measurements and the coefficient method. The actual measurement method uses a special measuring instrument combined with a scientific measurement method to monitor and calculate the flow rate and the concentration of the detected gas. This method has the characteristics of accurate measurement and high accuracy, but onsite measurements are relatively cumbersome to implement, and the monitoring cost is very high. It requires high technical standards for operators and poor practicability. Therefore, this method is only suitable for measuring carbon emissions in a small area. The carbon emission coefficient method was proposed by the IPCC in the first panel report of 1990. The carbon emission coefficient represents the amount of carbon emissions formed by a unit of energy during the consumption of various types of energy. According to the climate change committee’s assumptions, it can be determined that the carbon emission coefficient of a certain energy type is fixed: that is, in a hypothetical production environment, the amount of carbon dioxide emitted by a certain energy type can be calculated from the consumption of that type of energy. The carbon emission coefficient of each energy source can be directly checked from the IPCC’s report. The energy sources consumed by China’s logistics industry include crude oil, gasoline, kerosene, diesel, fuel oil, liquefied petroleum gas, natural gas, and electricity. Therefore, this study used the consumption of each of these energy types multiplied by the respective standard coal coefficient, then multiplied this by the respective carbon emission coefficient to calculate the carbon emissions of the logistics industry. The specific formula is as follows:
where
C is the carbon emissions,
i represents the energy type
i,
represents the carbon emissions of energy type
i,
is the coefficient of the energy type
i,
represents the conversion factor of the ith energy type shown in
Table 1 and
represents the consumption of the ith energy type. The carbon emission of the
ith energy is equal to the product of the carbon emission coefficient of this energy and the amount of converted standard coal, which is also equal to the product of the carbon emission coefficient of this energy, the coefficient of converted standard coal, and the energy consumption.
This study selected the energy consumption of China’s transportation, warehousing, and postal industries to represent the energy consumption of the logistics industry. The energy consumption data were taken from the China Energy Statistical Yearbook. As the latest statistics were 2020 data, the time frame of this research was 2010–2020. In the process of converting the various energy sources into standard coal, the conversion of electricity is unique. There are two main methods of converting electricity: one is the electric heat equivalent calculation method; the other is the method of calculating coal consumption for power generation. The primary energy composition and energy conversion rate cannot be distinguished in the conversion process of the electric heating equivalent calculation method. The power generation coal consumption calculation method is closely related to the energy structure, and carbon emissions are also related to the energy structure. Therefore, this study adopted the power generation coal consumption calculation method, and the conversion coefficients are shown in
Table 1.
3.2. LMDI Decomposition Method
Factor decomposition is proposed to analyze and study the influencing factors of changes in indicators such as economy, society, and environment. There are two most commonly used decomposition methods [
37,
38]: structural decomposition method (SDA) and exponential decomposition method (IDA). The SDA method is mainly based on a large amount of data, establishes an input–output model, and decomposes and analyzes the research objects; while the IDA method only requires a single industry data and the data is easy to collect. Compared with the SDA method, the IDA method requires a small amount of data, and the continuity of the data can facilitate the study of the changing trend of the subject in a period of time [
39].
In exponential decomposition analysis, the most commonly used methods are the Laspeyres and the logarithmic mean divisia exponential decomposition (LMDI) methods. The former is expressed in the form of percentage change, while the latter is based on logarithm, which studies the weight change of the influencing factors to the total change. Compared with the Laspeyres exponential decomposition method, LMDI is easy to model and has additivity [
40]; the decomposition process can be expressed in the form of multiplication and addition, and the conversion is easier; the residual of the decomposition result is 0. Combined with the characteristics of the research object of this paper, logistics as an industry, it was difficult to obtain input–output data, and it was difficult to establish an input–output model, and one of the purposes of this paper was to study the changes in the influencing factors of regional logistics carbon emissions within a certain period of time. Considered comprehensively, the LMDI method is more suitable [
41]. Compared with other decomposition methods, LMDI has many advantages: (1) Multiple influencing factors can be decomposed, and the factor decomposition result does not contain residual items that cannot be explained, and the residual is zero. (2) Multiplicative decomposition and additive decomposition are consistent, and the results obtained by these two methods can be converted into each other. (3) The results of applying the LMDI decomposition method, since the results of the sum of utility and the total effect of the decomposition of each department are the same, the decomposition does not affect the overall results. This feature is very important in the multifactor AHP.
In the literature, the factors affecting changes in the carbon emissions of the logistics industry are energy factors (including the energy structure and energy intensity), carbon emission intensity, logistics factors (including logistics industry development, the utilization rate of logistics facilities, and the methods of transporting goods), economic development factors (including per capita GDP, urbanization level, etc.), population size, and relevant national laws and regulations, systems, and other factors [
42]. Among these factors, it is very difficult to quantify factors such as the utilization rate of facilities and equipment or relevant national laws and regulations, and the accuracy of their quantification is limited. This study therefore selected the following factors for research:
Economic development: When studying carbon emissions-related issues, many scholars found that regional economic development affects the development level and scale of logistics in a region, which is the internal demand driving force that promotes the development of the logistics industry and has a decisive influence on the scale and efficiency of logistics [
43,
44]. This article selected regional GDP from 2010 to 2020 and used 2010 as the base period to deflate it.
Logistics development level: The logistics industry is the most direct source of carbon emissions. The logistics industry continues to expand. Its relationship with the development of various industries in the regional economy is growing closer, which is important in economic development. The change trend of industrial value-added logistics and carbon emissions during the period is mainly an upward trend. The development of the logistics industry has the most direct impact on its carbon emissions [
45]. The study selected the added value of the transportation, storage, and postal industry, and used 2010 as the base period to deflate it.
Energy structure: Different energy types have different carbon emission coefficients.
Table 1 shows that the carbon emission coefficients of different types of energy are quite different. In this article, the proportion of certain types of fossil energy consumed by the logistics industry within total energy consumption was used to express the energy structure [
46,
47,
48].
Energy intensity: The logistics industry’s energy intensity has a strong correlation with carbon emission intensity. Energy consumption intensity reflects the energy utilization efficiency of the logistics industry, and changes in energy intensity also have an important impact on its carbon emission levels [
49,
50]. Here, the energy consumption required by the logistics industry per unit of value added was used to express the energy intensity.
By referring to how the selected factors were divided in the literature on carbon emissions, we used LMDI to decompose the logistics industry’s carbon emissions in year
t, which divides the influencing factors into carbon factor effects (CI), energy structure effects (ES), energy intensity effects (EI), logistics development effects (D), and economic scale effects (G). For these, the decomposition process is as follows:
In this formula, i is the type of energy consumption, t is the year, 0 is the base year data, this article represents 2010, and d represents different regions; represents the contribution of carbon factors to the logistics industry’s carbon emissions, represents the contribution of changes in the energy structure to the logistics industry’s carbon emissions, is the contribution of the change in the energy intensity to the logistics industry’s carbon emissions, is the contribution of development on the logistics industry’s carbon emissions, and is the contribution of the economic scale on the logistics industry’s carbon emissions. The logistics industry is a composite industry that integrates transportation, warehousing, postal services, and information services and is an important part of the national economy. Considering the principle of availability of index data, this paper did not include the index of "information platform" in the evaluation index system, because the information platform not only serves the logistics industry but also serves other industries in the entire regional economy, and the statistical yearbook does not include the index of "information platform". There is no information data divided into various industries, so the data of the information platform will not be analyzed for the time being. According to the data of "China Tertiary Industry Statistical Yearbook", the transportation industry, warehousing, and postal industry account for more than 92% of the logistics industry which can basically represent the overall development of the logistics industry. The logistics industry mentioned in this article refers to the transportation, warehousing, and postal industry. The data of the article were taken from the "Statistical Yearbook", "China Tertiary Industry Statistical Yearbook", and "China Energy Statistical Yearbook" of various provinces and cities in China over the years. In order to exclude the impact of price changes in the development of the regional logistics industry, the output value of the logistics industry was calculated at the constant price in 2010.
3.3. Decoupling Model
The LMDI decomposition model can decompose and analyze the driving factors of carbon emissions in the logistics industry but cannot specifically measure the relationship between regional carbon emission reduction and the development of the logistics industry. Therefore, "decoupling" is an effective tool to study the relationship between economic development and material energy consumption. At this stage, there are mainly two representative decoupling models: the first category is the economic cooperation and development group.
According to the decoupling factor model proposed by the OECD, the decoupling results mainly depend on the initial and final values; the OECD divides decoupling into relative decoupling and absolute decoupling [
51]. The second category is the decoupling index model proposed by Tapio, whose decoupling results mainly depend on the increase or decrease of decoupling elasticity. The Tapio decoupling model first introduced the concept of decoupling elasticity. Tapio [
32] defined the decoupling elasticity when studying the relationship between transportation and carbon dioxide emissions, which is the ratio of the percentage change in traffic volume to the percentage change in GDP over a specific time period. Compared with the OECD decoupling model, the advantages of the Tapio decoupling model are more obvious [
52]. First of all, the Tapio decoupling model considers two indicators, the relative amount change and the total amount change, which avoids the error caused by the OECD decoupling model due to the selection of gene stages, and improves the objectivity and accuracy of the decoupling measurement. Secondly, the phase division of the decoupling state of the Tapio decoupling model is more detailed, and it is not affected by the change of the statistical dimension, which can better reflect the relationship between variables. This paper adopted the Tapio decoupling model to study the decoupling relationship between the development of the logistics industry and carbon emissions. In this paper, the following formula was set as the Tapio decoupling index.
In the formula,
e represents the decoupling index,
C represents the total carbon emissions of the logistics industry, and
D represents the total output value of the logistics industry. The decoupling state can be divided into eight states (
Table 2), in which if the decoupling is stronger, the carbon emissions will be lower.
5. Conclusions and Implications
5.1. Conclusions
This study estimated the carbon emissions of the logistics industry according to the IPCC’s (2006) method, then used the LMDI model to explore the factors affecting carbon emissions in China’s logistics industry, and, finally, conducted a decoupling analysis of carbon emissions and the development of the logistics industry. The conclusions are as follows:
- (1)
Results of LMDL decomposition
The total carbon emissions in the east are higher than those in the central and western regions. This is mainly related to the economic aggregate of the region. The larger the economic aggregate, the greater the total carbon emissions. The increase in the eastern region has been greater than that of the central and western regions. In the west, this is related to logistics industry development in the region. From the perspective of China as a whole, the total carbon emissions of the logistics industry have been tending to increase, which further shows that China’s economy has had a long-term growth trend, which is consistent with the evolutionary trend of the level of economic development.
Compared with other indicators, the economic development has the greatest impact on the logistics industry’s carbon emissions. The impact of economic development on the three regions all changed in the same direction. At the same time, the impact of economic development on the central region was the smallest. Nevertheless, the effects of logistics output are similar across the three regions, showing the characteristics of first pulling and then restraining. The effects of energy intensity show large volatility and are mainly negative. The region with the greatest negative impact is the eastern region of China. After 2015, the energy intensity of the central and western regions was higher than that of the eastern region, and the eastern region began to decline rapidly in 2015, until the effects of energy intensity were less than zero. The central and western regions showed smaller restraining effects. The negative impact of the energy structure’s effect is not obvious, and the logistics industry is an energy-intensive industry. The structural effects are affected by macroeconomic forms and energy policies. In the early stage of industrial development before 2015, the inhibitory effect of the energy structure was poor. From 2016 to 2020, the energy structure’s effect had an inflection point. Since 2016, the energy structure’s effects began to show a downward trend, but the negative impact of the energy structure’s effect in the three major regions is not obvious.
- (2)
The decoupling analysis
From the results of the decoupling effects, it can be seen that the only provinces in the country that are strongly decoupled are Beijing, Shanghai, and Zhejiang, indicating that the development of the regional logistics industry and the environment have formed a benign interaction. There are 20 provinces in a state of weak decoupling, and the strong decoupling and weak decoupling provinces accounted for 76.67% of the country, indicating that most provinces in China have achieved definite results in reducing carbon emissions and should continue to maintain this trend and increase the implementation of carbon emission reduction efforts. It is recommended to strive to achieve a complete decoupling of carbon emissions from the output value of the logistics industry. At present, 13.33% of provinces are in a state of expansive negative decoupling, and 6.67% of provinces are in a state of connection with growth, indicating that these provinces should be the focus of future emission reduction efforts. The differences in carbon emissions for this industry across the country have clearly widened and differentiated low-carbon logistics development policies need to be formulated in accordance with local conditions.
5.2. Policy Suggestion
In the context of international emission reduction, China and the United States jointly issued the "Sino-US Joint Statement on Climate Change" and proposed that China’s carbon dioxide emissions will peak by 2030, and carbon dioxide emissions per unit of GDP will be reduced by 60% to 65% compared with 2005. This paper analyzed the influencing factors of logistics carbon emissions in different regions, which has important implications for China and other countries to reduce carbon emissions in the logistics industry, improve the operational efficiency of the logistics industry, and control carbon emissions to achieve low-carbon economic transformation. Combining the results of the empirical analysis, this article proposes suggestions for promoting the reduction of carbon emissions in the logistics industry from the following perspectives:
- (1)
Improve energy efficiency.
From the perspective of energy efficiency, energy efficiency is a key factor in curbing carbon emissions in the logistics industry. Energy efficiency can be improved from two aspects. One is the introduction of foreign advanced logistics technology and the use of advanced logistics technology to improve energy efficiency; the second is independent innovation, including innovation of the management system of logistics enterprises and the innovation of logistics operation processes. Reducing the costs of logistics and improving the utilization rate of logistics energy would help achieve the carbon emission reduction goals of the logistics industry.
- (2)
Formulate policies to promote low-carbon logistics development.
There are obvious regional differences in Chinese logistics industry. The formulation of carbon emission reduction policies should be more targeted. For western regions with small differences in interprovincial carbon emissions, a unified carbon emission reduction policy can be considered, while for regions with large interprovincial carbon emission differences, the process of formulating policies should vary from place to place. Local governments can combine the development level of the local logistics industry and the actual situation of carbon emissions and participate in the formulation of suitable rules.
- (3)
Actively adjust the energy structure of the logistics industry.
A reasonable energy structure is an effective measure to reduce the intensity of carbon emissions. At present, the energy structure of the logistics industry is mainly based on high-carbon fossil energy such as coal and oil. Energy intensity is the main reason for the decline in the carbon emission intensity of the logistics industry in Fujian Province. The rate of contribution of the energy structure is very small, increasing the carbon emissions. Therefore, it is necessary to accelerate the adjustment of the energy structure, promote the use of clean energy, increase the proportion of new energy in the total energy consumption, and reduce the carbon emission intensity of the logistics industry through reasonable adjustment of the energy structure and promoting the development of a low-carbon logistics industry.
- (4)
Strengthen informatization.
Informatization is an effective means to improve the efficiency of logistics operations, and it also provides important technical support and guarantee for the development of low-carbon logistics. The public information platform of logistics can effectively realize the transmission of information throughout the main body of the logistics supply chain, realize the integration and reasonable allocation of logistic resources, and improve the operational efficiency of enterprises. The construction of a public information platform for logistics would provide conditions for the realization of the common distribution of logistics enterprises. Logistics enterprises jointly use logistics facilities and equipment through the information platform, which would reduce the empty load rate during transportation, and reduce repeated transportation and ineffective transportation. In turn, this would reduce energy consumption and carbon emissions through rationalization and efficiency in all aspects of logistic activities.
5.3. Research Values and Limitations
On the one hand, the research of this paper promotes the integration of economics, sociology, and management, which is conducive to the further development of management; on the other hand, it expands and deepens the research field of energy and environmental issues and enriches the research perspective. This paper took the logistics industry as the research object, which is conducive to improving the research framework of energy and environmental science. Finally, this paper adopted the national and regional research on the emission of logistics industry, which is conducive to excavating and discovering the actual characteristics of energy and environmental problems in different regions and provinces, making policy recommendations more pertinent, to improve the operability of the policy.
The issue of regional logistics carbon emissions has been a hot research topic in the academic circles in recent years. This paper carried out preliminary research on it. It is in the preliminary and superficial research stage. Although some research conclusions have been obtained, due to the limitation of personal level and ability, the research on the differences and influencing factors of regional logistics carbon emissions still needs to be further explored, and needs to be improved and perfected from the following aspects:
1. When analyzing the carbon emission characteristics of the logistics industry, this paper selected the carbon emission intensity, energy structure, economic development, and the development of the logistics industry to analyze its carbon emissions. There is a lack of interaction mechanism between measurement indicators and carbon emission characteristics. The path is explained indepth.
2. Lack of indepth research on industry logistics. The logistics industry involves a very wide range, and every industry in the national economy has logistics. Due to industry differences, there are many differences in energy consumption and carbon dioxide emissions in logistics in different industries. This article was based on the logistics industry from a broad perspective and does not reflect industry differences. In the future research, it is necessary to conduct indepth research in combination with industry logistics.
3. The optimization and adjustment of regional logistics itself is very important to improve the level of low-carbon development, but it also requires the cooperation of the industry, which requires the impact mechanism and degree of influence of different industries on the logistics industry in each region, so as to reach the purpose of the interindustry common development.