基于能值分析的城市生态经济系统可持续性评价-以天津市为例

Sustainability Assessment of Urban Ecological-economic System Based on Emergy Analysis: A Case Study of Tianjin

摘要:

在“双碳”目标背景下，从关注不同物质、能量和服务之间质的差异以及社会经济系统和自然环境之间相互作用的复杂性的角度评价城市生态经济系统的可持续性。以天津市为例，基于能值分析理论，对生态系统的调节服务和文化服务进行量化，从社会、经济、环境3个维度探讨其2008－2020年生态经济系统资源输入、产出、系统服务所带来的环境压力与可持续发展之间的关系。结果表明：天津市近10年来经济快速发展主要以外部能值输入和不可再生资源的消耗来拉动，能值自给率下降，经济发展对外界依赖程度增强；环境负载率持续增长，2020年的增长幅度达238%，生态经济系统可持续发展潜力持续变弱，对生态环境造成极大压力，自然生态系统已处于超负荷运转状态；系统的能值交换率、能值密度和人均能值量呈现增长态势，能值集约水平高；调节服务功能是整个生态系统服务的重中之重，且再生资源能值以及购买和外部来源对整个系统的可持续性发展指数影响较大。因此，天津市应不断发展绿色创新技术，推动能源结构优化和产业转型升级。

Abstract:

Under the background of the goal of "double carbon", the sustainability of urban eco-economic system is evaluated from the point of view of paying attention to the qualitative differences between different materials, energy and services, as well as the complexity of the interaction between socio-economic system and natural environment. Taking Tianjin as an example, the regulation services and cultural services of ecosystem are quantified based on emergy analysis theory. This paper discusses the relationship between environmental pressure and sustainable development caused by the input, output and system services of eco-economic system resources from 2008 to 2020 from the three dimensions of society, economy and environment. The results show that: the rapid economic development of Tianjin in the past 10 years is mainly driven by external energy input and the consumption of non-renewable resources, the emergy self-sufficiency rate has decreased, and the degree of dependence on the outside world for economic development has increased; the environmental load rate has continued to increase, with an increase rate of 238% in 2020. The sustainable development potential of the eco-economic system continues to weaken, causing great pressure on the ecological environment, and the natural ecosystem has been in a state of overload operation. The emergy exchange rate, emergy density and per capita emergy of the system show an increasing trend, and the emergy intensive level is high, and the regulation service function is the top priority of the whole ecosystem service.The emergy of renewable resources and the purchase and external sources have a great impact on the sustainable development index of the whole system. Therefore, Tianjin should continue to develop green innovation technology to promote the optimization of energy structure and industrial transformation and upgrading.