Dynamic Changes of Land Ecological Carrying Capacity Based on the Ecological Footprint——By the Case Study of Chengdu City

Chengdu City is in the period of rapid urbanization and industrialization, and the disturbance derived from human activities on environment is increasing remarkablely in recent 20 years. The pressure on environment, economy and population is also increasing and land use in Chengdu has changed enormously. As struc- ture and function of land ecological system change obviously, sustainable development of land productivity has been an important goal and strategic task from now on, and it is necessary to systematically research land ecological carrying capacity based on ecological footprint. The ecological footprint of Chengdu City in the past ten years was calculated and analyzed from the spatial and temporal aspects according to statistical data from 1998 to 2008, as per ecological footprint method, ecological carrying capacity and the GIS spatial analysis method, and regression analysis method. The ecological footprint and ecological carrying capacity values from 2009 to 2019 in Chengdu City were predicted through calculation results in the past ten years. The results show that the ecological footprint and ecological deficit of land use from 1998 to 2008 increased in Chengdu City. The ecological deficit of land use within the city center was in high levels in the past ten years, and the ecological footprint kept raising, especially in areas, such as Shuangliu, Chongzhou, Qingyang among 9 city areas, 4 counties and 6 districts in Chengdu City. There is fanlike distribution of ecological deficit of land use. Analysis shows that the social and natural ecological system is uneven distribution, which is not in sustainable de- velopment situation. The results of the study show that the economic, social and natural ecological system in Chengdu City is not sustainable, and the ecological foot- print is uneven distribution. The analysis of the dynamic change of land ecological carrying capacity in Chengdu City is very important for city government in the pro- cess of the vigorous development in new Tianfu Xinqu, and redevelopment in the northern part of this city.

Sustainable Development Strategy and Tactics of Small Enterprises under Market System

Based on an analysis of small enterprises’features,com-bined with an example which the authors experienced,the sustainable development strategy and tectics that thesmall enterprises can adopt in the new century are dis-cussed and presented in this paper.These strategies arefocusing on one target strategy,finding the vacancystrategy,management characteristic strategy,unitedcompetition strategy and contract management strategy.And the tactics are internal reformation,united refor-mation,technology purchase and technology transfer-ring.

Evolving perspectives on biofuels in the United States

Biofuels represent an important source of renewable energy and may play a crucial role in developing sustainable energy strategies for many countries and the world as a whole. The pros and cons of biofuels, however, have been debated both scientifically and politically. They remain a topic of controversy. In this paper, the evolvement of the perspectives and policies on biofuels in the United States in the past several decades was reviewed. Four different periods, that is, the period prior to 1978 （marked by the passage of the Energy Act in 1978）; 1978-1989 （ending with the passage of the Clean Air Act Amendments of 1990）; 1990-2004 （ending with the passage of the energy act of 2005）; and 2005 to the present, which were characterized by defining events of major policy importance were identified. Each time period was assessed using the Ostrom institutional analysis and development （IAD） framework to show the impact of the evolving interests and influences of global players on policy choices related to biofuels in the United States. The US has a long history of supporting corn-based ethanol and more recently advanced biofuels. Changes in perspectives on biofuels from largely unrelated groups led to changes in policy and market dynamics. Until the late 1990s, most perspectives and policies tended to be aligned and significantly supportive of corn-based ethanol in the United States. In the early 2000s, it became clear that the complications associated with first generation biofuels and corn-based ethanol in particular, were too numerous and too severe to overlook. The need for better options has spurred interest in new technologies and more environmentally benign feedstocks, but, there is little prospect forbiofuels playing a significant role in the near term without greater alignment among key players.

Eco-Industry: A New Pattern for Industrial Development

Eco -industry is a new pattern for industrial development. This paper briefly reviews the progress of eco -industry. The research work of Center for Industrial Ecology, Chemical Engineering Department, Tsinghua University is well introduced. Several academic issues that need further research are suggested from a system engineering point of view.

Sustainable public-private partnerships： Balancing the multi-actor ecosystem and societal requirements

The funding gap of public infrastructure networks(roads, railways, ports, electricity, and energy lines)can be solved partly by introducing private capital for investments, i.e., public-private partnerships(PPP). This paper introduces an integrated model of a PPP project and investigates its implications on PPP policies and strategies regarding appropriate project appraisal and selection. The model has different resolution levels, namely, project level,business ecosystem level, and market and societal levels.The integrated model suggests that investing in merely financially viable projects is insufficient to realize economically and socially sustainable and acceptable projects.