It is important to study flexibility analysis method of large scale systems with material flow links between subsystems , for example, in the study on industrial ecosystem.

After reviewing relative returns,the authors present 5 hypotheses about structural influential factors in the stability of industrial ecosystem(IES) in China: keystone species enterprise,member distance,member reliability,industry diversity and conductor factor.

Dynamic analysis of emergy for agro-ecosystem in the region of cropland to grassland conversion ——A case study of Beizhuang Village,Zhenyuan County in Gansu Province;

A review upon the importance and effect of piling soil to ridge with non-tillage for agro-ecosystem in central hilly area of Sichuan Basin;

Emergy assessment on succession and sustainability of the agro-ecosystem in Huang-Huai-Hai Plain, China;

Harmony coefficient theory and case study on agricultural ecosystem;

The application of isotopic tracing technology to agricultural ecosystem;

Optimization production model of agricultural ecosystem in the ecotone between agriculture and animal husbandry in Northeast China;

The resemblance and difference between industrial ecosystem and natural ecosystem was studied, with description of resemblance of material circulation, energy flow, inherence motility, evolution, keystone species and symbiosis.

Using input-output model,a basic material flow analysis frame for the industrial ecosystem is constructed,on the basis of which the methods of distinguishing key species enterprises,analyzing energy consumption characteristics and measuring the amount of cumulative pollution of enterprises in the industrial ecosystem are put forward.

System analysis and modelling method was used to describe industrial ecosystem and industrial eco-chain based on industrial metabolism.

Evaluation and analysis on agro-ecological system of Maowusu Sandland;

The Energy Flowing Aanalysis of the Agro-Ecological System of the Red Soil Watershed——Taking the Agro-Ecolegical System of Ganshang Watershed as an Example;

With Shiyang Watershed in the West Bank of the Yellow River as an example,thispaper analyses the effects of human management level,agro-climatic suitability,soil fer-tility,water resources,natural productivity of oasis in various sections,economic returnsof water use,and productive efficiency upon oasis agro-ecological system.