Abstract: In recent years, China puts ecological civilization construction as a national development of the layout, which shows that the CPC Central Committee attachs more importance to the construction of ecological civilization. Ecological civilization construction evaluation is one of the key links. At present, ecological development in China is seriously lagging behind the economic and social development. In view of this problem, an evaluation model is put forward to measure coordinated development degree of the three subsystems of economy, society and nature,in order to promote the development of economic, social and natural keep in harmony.
The healthy development of ecological civilization both needs a high level of comprehensive development and a high degree of coordinated development. In this paper, the optimal index is built to measure the comprehensive development level of each province, and the uniform index is built to measure the coordinated development degree of each province. Firstly, index system is constructed from the angle of the three subsystems which is the economic, social and natural system respectively. Secondly, in the subsystem, the weight of each index and the comprehensive evaluation value of each subsystem are calculated by order relation analysis method and arithmetic weighted average operator. Thirdly,the optimal index is constructed by calculating the mean distance between the comprehensive evaluation value and its minimum value of every province. The uniform index is constructed by calculating the logarithm of the distance between the three subsystems' evaluation values and their mean value. Finally,according to the statistical data of China Statistical Yearbook, China Statistical Digest and China Environmental Statistical Yearbook, using above-mentioned evaluation model, the coordinated development degree of ecological civilization construction of 31 provinces in China is evaluated.
The evaluation results show that the development level of the three subsystems of every province is in a state of unbalanced development, and the optimal degree index is negatively correlated with the degree of consistency index. The results also show that there is a certain relationship between the level of ecological civilization development and geographical distribution in China, and it is necessary to take different measures according to the characteristics of different regions.
Ecological civilization construction coordination level evaluation is a very complex question, and many factors need to be considered. However, the most important thing is to grasp the definition of the ecological civilization coordinated development. Considering the coordination level of ecological civilization construction from three subsystems of economy, society and nature, it not only requires the development level of the subsystems to be synchronized,but also requires the development of every subsystem should continue to improve. Therefore, the optimal index and uniform index are construeted to reflect the coordination level of ecological civilization construction. The method can also be applied to other subsystems. At the same time, the order relation analysis method is used to determine the weight of indexes in each subsystem, can express the experts' opinion simply and accurately. In addition, the evaluation method of statistical index analysis is advanced and flexible, in which the evaluation index system can be constructed, weight can be determined and information aggregation model can be chosen.

Key words: ecological civilization construction, coordinated development, comprehensive evaluation, optimal index, uniform index