[Adaptability assessment of economic and environmental development of Tangshan, Hebei, China].

It is vital to explore whether the economic system adapts to the environmental system as the relationship between economy and environment becomes a gradually concerned problem. Tangshan, a typical resource-based city, was chosen to study the adaptabilities and performances of economic developments in response to environmental changes from 1992 to 2011. It was found that the economic-environmental adaptation curve of Tangshan City had an overall fluctuating and increasing tendency. The systematic adaptability kept advancing, reflecting Tangshan paid much attention to environmental development in addition to economic performances, and the two aspects became more and more coordinated. Filtering analysis of the adaptive curve with Eviews software revealed that the potential systematic coordinating index was rising continuously, however, the sum of resilience gap for 20 years was still negative, which implied that fundamental contradictions between high economic development and high energy consumption and high pollutant emission still existed. Carrying out adaptive researches not only helps people to adapt to climate changes better, but also has significances for economic and environmental coordination and sustainability research.

[Coordinated evolvement of dynamic coupling between economic and environmental systems in Shenyang Metropolitan area].

By using coupling coordinated degree model, scissors difference methods, and coupling degree model, this paper analyzed the coupling coordinated status, development speed difference, and coupling development trend between economic and environmental systems in Shenyang Metropolitan Area in 1990-2009. In the study period, the coupling level of the relations between economic and environmental development was ascending, with the coupling degree increased from 0.42 to 0.89, which reflected the more and more harmonious relationships between economy and environment. The decrease of economic development speed and the increase of environmental construction speed reduced the scissor difference of the two systems from 0.63 degrees to 0.22 degrees, demonstrating the contribution of the economic development speed to the coupling coordinated status. The coupling degree between the economic and environmental systems stretched across in a [45 degrees, 90 degrees] region, which meant that the two systems were in a co-developing status. As the discrepancy between the development speeds of the two systems became smaller, the coupling degree was closer to 45 degrees, and the two systems were becoming better coordinated.