Shengsheng Li

Ecological relationship analysis of the urban metabolic system of Beijing, China.

Cities can be modelled as giant organisms, with their own metabolic processes, and can therefore be studied using the same tools used for biological metabolic systems. The complicated distribution of compartments within these systems and the functional relationships among them define the systems network structure. Taking Beijing as an example, we divided the citys internal system into metabolic compartments, then used ecological network analysis to calculate a comprehensive utility matrix for the flows between compartments within Beijings metabolic system from 1998 to 2007 and to identify the corresponding functional relationships among the systems compartments. Our results show how ecological network analysis, utility analysis, and relationship analysis can be used to discover the implied ecological relationships within a metabolic system, thereby providing insights into the systems internal metabolic processes. Such analyses provide scientific support for urban ecological management.

Ecological network analysis of China’s societal metabolism

Uncontrolled socioeconomic development has strong negative effects on the ecological environment, including pollution and the depletion and waste of natural resources. These serious consequences result from the high flows of materials and energy through a socioeconomic system produced by exchanges between the system and its surroundings, causing the disturbance of metabolic processes. In this paper, we developed an ecological network model for a societal system, and used China in 2006 as a case study to illustrate application of the model. We analyzed Chinas basic metabolic processes and used ecological network analysis to study the network relationships within the system. Basic components comprised the internal environment, five sectors (agriculture, exploitation, manufacturing, domestic, and recycling), and the external environment. We defined 21 pairs of ecological relationships in Chinas societal metabolic system (excluding self-mutualism within a component). Using utility and throughflow analysis, we found that exploitation, mutualism, and competition relationships accounted for 76.2, 14.3, and 9.5% of the total relationships, respectively. In our trophic level analysis, the components were divided into producers, consumers, and decomposers according to their positions in the system. Our analyses revealed ways to optimize the systems structure and adjust its functions, thereby promoting healthier socioeconomic development, and suggested ways to apply ecological network analysis in future socioeconomic research.

Research on the Eco-City Index System Based on the City Classification

Due to the different ecological characteristics of the cities, the current national standard can not normalize the eco-city construction in China. To solve this problem, this paper puts forward a new method to set up different index systems based on the classification of cities, i.e., represent the generality of the cities by a set of common indices for comparison; classify various cities by a set of characteristic indices for identification of cities of the same type; and finally, specialize each city with several additional feature indices. This paper also presents the city-classification and the common and characteristic indices that are suitable for Chinese cities, as well as examples of the feature indices for specific city.

Measurement and evaluation of the material metabolism capability in typical Chinese cities

Based on neoclassical economic theories, such as the production possibility curve (production possibility frontier) and the social welfare indifferent curve, a model to measure urban material metabolism was proposed and an urban development mode was determined in this paper. Taking twelve typical Chinese cities as study subjects, the metabolic flux and eco-efflciency of water, energy and waste were calculated with a measurement model and their metabolic capabilities were evaluated extensively on their eco-efflciency and eco-equity ability. On the basis of material metabolism capability evaluated with the index of eco-efflciency and eco-equity, policymakers can determine the root cause of urban eco-environmental problems and take measures to optimize the process of urban material metabolism to achieve healthy urban ecosystem.

Two improvement approaches on ecosystem services valuation

Ecosystem services valuation is a widely accepted method to evaluating an ecosystem. And the similar calculating methods that different researchers adopt have a mutual shortage that it can not express the spatial differentiation of ecosystem. This article brings forward approaches to improve the method by eliminating area factor and adding structure character factor, especially emphasizing the significant effect of landscape pattern fragmentation. Additionally, a case study indicates that the improved method can get more abundant and more effective results than the original one.

On China's Endosomatic and Exosomatic Metabolism: An Application of Analysis of Societal Metabolism

The metabolism of human society is a concept used to characterize the processes of energy and material transformation in a society which are necessary for its continued existence. In order to improve the traditional input-output analysis method and the black-box analysis model, the societal metabolic ecosystem of china was divided into different components to establish societal metabolic ecosystem model to analyze metabolic processes and account the eco-flows between components, and determine the hierarchy relationship between the various components. Two indexes (the contribution index and the development pressure index) were put forward to analyze the metabolism of china. This paper could be the scientific basis for the sustainable development.

Coupling Mechanism for Building up Harmonious City

In order to realize ‘win-win’ between economic development and environmental protection, it is necessary to study the coupling mechanism of economic development and environmental protection. The paper builds up the reversible equation and optimum principle of coupling mechanism of economic development and environmental protection, and provides the measure standard. Jilin Province is selected as an example. The quantitative analysis of economic development and environmental protection is based on the sixteen indicators that are representative in 9 cities of Jilin Province. The two main factors - economic development and environmental protection, are screened by factor analysis method, and the coupling mechanism of economic development and environmental protection is assessed. The results show that the development of most cities in Jilin Province is environment and economy lagging status of rudimentary development level, except Changchun City and Jilin City; both are at advanced development stage. On the basis of the assessment, conclusions and suggestions about sustainable development of economy and environment are printed out, and they can be used for reference for subsequent studies.

Perspective of Biological Invasion and its Consideration

Biological invasion is a major threat to biodiversity globally. It not only affects ecosystem structure and function, but also brings the economic and environmental impacts. To curb the societal, economic and environmental impacts of alien invasive species (AIS), we need realize the current status and hazard of biological invasions, and understand the invasive routes and mechanisms. Finally, we provide the theoretic connotation of biological invasions according to entropy increasing principle of Second Thermodynamics Law, and some advises on controlling biological invasions. Biological invasions, also called biological pollution, have two-dimension danger at horizontal and vertical scale, and two-channel way in natural and artificial way. The key of studying biological invasions is mechanism and principle. The mechanism of biological invasions focuses on the biological and ecological characteristic of alien invasive species, and frangibility of habitat. Its theoretic connotation embodies following aspects: entropy increasing of ecosystem will conduce to the degradation of energy; negative entropy is the source of life; biological invasion is the course of inputting positive entropy to ecosystem.