Abstract

Xinjiang is a representative of arid and resource-based areas in China, cov-ering about one-sixth of the country's land area, but desert covers about 60% of the country's total desert area. Xinjiang is short of water, lacks natural ecological resources, and the ecological environment is extremely fragile. It is also a region rich in natural resources and has a large amount of coal, oil, natural gas, and va-rious kinds of mineral resources. However, these two characteristics greatly re-stricted the economic development of Xinjiang, resulting in unbalanced regional development, mineral exhaustion, restrictions on the scale of industrial develop-ment, ecological and environmental damage, and other consequences. To solve these problems pertinently, we collected agricultural, industrial, and the compre-hensive panel data of 14 prefectures in Xinjiang from 2001 to 2015, and construct the ecological efficiency evaluation index system using the super-effi-ciency DEA model in which the resource consumption and environmental pollution were set as input indicators and economic value as output indicators. The spatial and temporal distribution and change characteristics of agriculture, industry and comprehensive eco-efficiency were continuously and comprehensively measured and analyzed at the provincial level, regional level and prefectural level. Malmquist index was used to analyze the dynamic changes of important in-dexes such as total factor productivity, comprehensive technical efficiency, tech-nical efficiency and scale efficiency, and the mechanism of promoting and restric-ting ecological efficiency. The causes of ecological efficiency loss were analyzed from the perspective of input-output redundancy and improvement approaches are proposed. The influencing factors on ecological efficiency and the mechanism of these factors on ecological efficiency were studied with the Tobit model. Finally, we put forward targeted strategies for improving ecological efficiency according to the above results, so as to provide a basis for ecological civilization construction and green and sustainable development in Xinjiang. The specific conclusions are as follows：

1. The Agricultural Ecological Efficiency of Xinjiang

（1）Compared with other areas in China, the agricultural ecological effi-ciency of Xinjiang is low. The agricultural ecological efficiency of Xinjiang is 0.67, ranking the 28th in China, which is only 1/3 of that of Hainan. Even com-pared with the five provinces or regions in northwest China, Xinjiang is still in a backward position, indicating that the overall agricultural ecological efficiency is still low and is lagging in the country.

（2）Unbalanced spatial distribution. The comparison of the agricultural eco-logical efficiency among the 14 prefectures in Xinjiang shows that the lowest eco-logical efficiency value was 0.71, the highest was 3.68, about 5.18 times that of the former. The average value of agriculture ecological efficiency of northern Xin-jiang, eastern Xinjiang, and southern Xinjiang were 1.30, 1.39, 1.07, all of which achieved the efficient production frontier. The obvious differences among the three regions showed that the spatial distribution of agricultural development among regions was unbalanced. Among the 14 prefectures, only 4 prefectures （Karamay, Turpan, Kashgar, and Bazhou）had an agricultural ecological effi-ciency value greater than 1 and reached the effective production frontier, indica-ting that the level of ecological efficiency in most areas was relatively low.

（3）The time series analysis from 2001 to 2015 shows that although the agri-cultural ecological efficiency has a small fluctuation, it presents an overall trend of the increasing year by year. From 0.62 in 2001 to 1.03 in 2012, and from 2012 to 2015, the agricultural ecological efficiency has been greater than 1 for four consecutive years, reaching the effective production frontier. The value raised from 0.68 during the“10th five-year plan”to 0.76 during the“11th five-year plan”, then to 1.01 during the“12th five-year plan”. The agricultural eco-logical efficiency was gradually improved, from the ineffective state to the effective production frontier. These indicated that Xinjiang realized the economic growth of agricultural production, resource conservation, and environmental pro-tection during the three five-year plans through adjustments in development with national support policies such as the Central Xinjiang Work Symposium and assists from 19 provinces.

（4）Through Malmquist index decomposition analysis, we found that the technology progress index contributed the most to the improvement of agricultural ecological efficiency and was the promoting factor for the improvement of agricul-tural ecological efficiency, while the technical efficiency index restricted the in-creasing of agricultural eco-efficiency. Therefore, the key to improving agricultural ecological efficiency is to strengthen agricultural technology research and support and promotion. Secondly, it is necessary to improve the application level of agricultural technology, control the scale of input, reduce the excessive use of fertilizers and pesticides, and reduce the waste of resources.

（5）The input-output redundancy analysis showed that the reason for the loss of agricultural ecological efficiency of Xinjiang was not the lack of agricultural output, but the excessive consumption of resources and excessive dis-charge of environmental pollutants. The average redundancy rate revealed the main factors causing the loss of agricultural ecological efficiency were COD emis-sions, effective irrigation area, ammonia nitrogen emissions, sown area, and the number of the rural labor force.

（6）The influencing factors analysis revealed that the agricultural industrial structure, the per capita GDP, the financial support was significantly positively related to the agricultural ecological efficiency which had promotion effects to the later. In contrast, the current development level of industrialization, the density of machinery was significantly negatively with the agricultural ecological efficiency which inhibited the agricultural ecological efficiency. Therefore, all regions should adjust the structure of the agricultural industry, increase financial support for agriculture, boost farmers' income, and other aspects to promote the rational allocation of resources and improve agricultural ecological efficiency.

2. The Industrial Ecological Efficiency of Xinjiang

（1）Compared with other areas in China, industrial ecological efficiency was low. The industrial ecological efficiency of Xinjiang was 0.73, ranking the 28th in China, about 16.44 percent of that of Hainan, and about 56.59 percent of the national average. Among the five provinces or regions in northwest China, indus-trial ecological efficiency in Xinjiang was higher than that of Gansu, Ningxia, and Shanxi Province. Across the country, industrial ecological efficiency in Xinjiang was still at the bottom place, showing that the overall industrial ecological effi-ciency was relatively low.

（2）The spatial distribution was unbalanced. The comparison of industrial ecological efficiency in the 14 prefectures in Xinjiang revealed that the highest was 8.97, and the lowest was 0.59, with an average value of 1.86. The 15 years average industrial ecological efficiency in northern Xinjiang, eastern Xinjiang and southern Xinjiang was 2.04,2.85, and 1.21, respectively. They all reached the efficient production frontier, but there were obvious differences between the three regions, which showed that there was an unbalance in the development of the in-dustrial economy of Xinjiang.

（3）From 2001 to 2015, the overall industrial ecological efficiency of Xin-jiang showed a fluctuated upward trend. The ecological efficiency rose steadily from 0.75 during the 10th five-year plan period to 1.00 during the 11th five-year plan period and then to 1.08 during the 12th five-year plan period, the ecological efficiency kept above 1 and maintained at the frontier of effective production since the end of the 11th five-year plan period in 2010.

（4）The comparative analysis between the super-efficiency DEA model and CCR model showed that the ecological efficiency value calculated and measured by the super-efficiency DEA model was more accurate, and it could even work well after reaching the effective production frontier with a value greater than 1.00, which was conducive to the quantitative analysis of regional ranking and disparity.

（5）The Malmquist index decomposition analysis found that the technology progress index was the primary factor restricting the total factor productivity, while the technical efficiency and pure technical efficiency index were the promo-ting factors. It indicated that the application level of industrial technology of Xin-jiang was growing, while the introduction and research & development of industrial technology were not enough, and need to be strengthened.

（6）The input-output redundancy analysis indicated that the main factors causing the loss of the industrial ecological efficiency were industrial sulfur dioxide emissions, industrial nitrogen oxides emissions, industrial waste gas emis-sions, industrial electricity consumption, and industrial water consumption. Over-all, there were severe excess emissions of air pollutants across Xinjiang.

（7）The level of industrial development, scientific and technological innova-tion, industrial structure, and environmental planning was positively correlated with the industrial eco-efficiency which promoted the industrial eco-efficiency, while the opening up and industrial agglomeration were negatively correlated with the industrial eco-efficiency which inhibited the industrial eco-efficiency. There-fore, it needs to enhance the level of industrial development to improve industrial ecological efficiency. Besides, it also should improve the level of technology re-search and development and promotion of industrial enterprises, strengthen envi-ronmental planning and management of environmental protection, and be cautious in introducing foreign investment.

3. The Comprehensive Ecological Efficiency of Xinjiang

（1）Across all the areas in China, the level of ecological efficiency of Xin-jiang was low and the allocation of resources was unreasonable. The comprehensive ecological efficiency of Xinjiang ranks the 31st, with a value of only 0.562 2, nearly 60.19 percent of the average value and about 23.11 percent of the first place of Beijing, indicating that the comprehensive ecological efficiency of Xinjiang was still very low. The ranking of resource efficiency was the 30th in China, while the ranking of environmental efficiency increased to the 22th in China. It indicated that the low ecological efficiency of Xinjiang was mainly caused by low resource efficiency. And inappropriate allocation of re-sources, large consumption of resources, and the high consumption of energy were still the characteristics and status quo of economic development of Xinjiang.

（2）Unbalanced spatial distribution. The values of ecological efficiency in northern Xinjiang, eastern Xinjiang, and southern Xinjiang were 1.61, 1.17, and 0.81 respectively. The comparison among the 14 prefectures showed that the highest ecological efficiency was 4.19 and the lowest was 0.48. There was a big difference in regional ecological efficiency. Of the 14 prefectures, only Karamay City and Turpan City had an ecological efficiency value greater than 1 and reached the effective frontier. These implied that the overall ecological efficiency was low in Xinjiang.

（3）From 2001 to 2015, the ecological efficiency of Xinjiang increased in a fluctuating mode, with a final increase of 5.7%. At the scale of the five-year plans, the ecological efficiency increased from 0.988 1 during the 10th five-year plan period to 1.063 8 during the 11th five-year plan period and to 1.064 3 dur-ing the 12th five-year plan period.

（4）The ecological efficiency was further decomposed into resource efficiency and environmental efficiency and analyzed. According to the different combination of resource efficiency and environmental efficiency, the development modes of each region in Xinjiang was divided into four types: low energy con-sumption and low emission mode; high energy consumption and low emission mode; low energy consumption and high emission mode and high energy con-sumption and high emission mode.

（5）Through Malmquist index decomposition analysis, we found that the technology progress index was the main influencing and restricting factor of eco-logical efficiency. The comprehensive technical efficiency index, pure technical efficiency index, and scale efficiency index played a certain role in promoting the ecological efficiency. Therefore, further strengthening the introduction and research and development of new technologies were very important to improve ec-ological efficiency.

（6）The input-output redundancy analysis suggested the main reason for the loss of ecological efficiency was not the lack of output, but the excessive con-sumption of resources and excessive discharge of environmental pollutants. The main influencing factors causing ecological efficiency loss were COD emission, ammonia nitrogen emission, water resource input and labor force input. The total amount of water consumption and the total amount of drainage of Xinjiang were seriously excessive. Saving water resources in arid areas is a fundamental problem, so it is urgent to improve the allocation and utilization of water resources in the future.

（7）The utilization of foreign capital, urbanization rate, average education level, and proportion of tertiary industry were positively correlated with ecological efficiency, while environmental policy and marketization degree were negatively correlated with ecological efficiency. Therefore, to further improve the ecological efficiency of Xinjiang and ensure the coordinated and sustainable development of the environment, economy, and society in the future, it is necessary to strengthen the construction of urbanization, strengthen the level of scientific and technological research and application, adjust environmental protection policies to make them more targeted and effective, strengthen the management of non-public enterprises, encourage foreign investment that is conducive to the sustainable de-velopment of Xinjiang, and lastly adjust and optimize the industrial structure and gradually increase the proportion of the tertiary industry.

4. The Strategy of Improving Ecological Efficiency of Xinjiang

We sorted out the problems in the research of ecological efficiency and dis-cussed several ways for Xinjiang to enhance ecological efficiency from multiple as-pects, such as, promoting the optimization and upgrading of industrial structure transformation of economic developing pattern, promoting economic restructuring, improving the quality of economic, strengthening the scientific and technological innovation and the introduction of new technology, utilizing of foreign capital, improving the quality of foreign capital, strengthening environmental planning and environmental protection management. This study aimed to provide an important basis and guidance for the development of the great beauty of Xinjiang.

Keywords: Arid Resource Region; Xinjiang; Ecological Efficiency; Super Efficiency DEA Model; Promotion Strategy