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The demand for coal resources is increasing with economic development in China.But,the rich mineral resources along with the intensive mining activities,which have led to a lot of ecological and environmental problems,such as environmental pollution,ecological destruction and geological disasters.Eco-risk assessment is an important tool for effective ecological environment management with evaluations of the likelihood and degree of harm. Thus,this paper applied landscape eco-risk assessment methods to estimate the level of the opencast mine area eco-risk.But also the ESDA(Exploratory spatial data analysis) methods were used to analyze the spatial association characteristic of landscape eco-risk in mining area.It turned out that those high-risk areas is the core of the spatial distribution of Landscape eco-risk and from high-risk to low-risk present ring features.In addition,high-risk is mainly distributed in the mining industry and city life areas,sources of which are the mining,coal gangue tie up land and city construction activities.Medium-risk are mainly distributed in nature,half natural functional areas,the main sources of which are the city life and the agricultural production activities.Low-risk areas are covered by sparse vegetation,such as shrub and grassland.However,in research areas,vegetation degradation,soil and water loss leads to the regional ecological base quality was poor.So the ecosystems and environmental factors are fragile here.Moreover,the frequent production activities in mining areas cause more serious ecological and environment problems.The risk degree of the artificial area is higher than the half natural area,and the half natural area is higher than the natural area.It is conform to the conventional law of ecological risk level difference.At the same time,based on the ESDA of the landscape eco-risk in opencast mine area,the space correlation of the risk is up to 0.7521,which indicate that the agglomeration features of the risk obviously.Different characteristics of agglomeration provide the basis for the ecological and environment management.Space differentiation study of Landscape eco-risk in this opencast mine area shows that interference are the main driving factors in the high-risk and low-risk areas.But in the medium-risk area,fragile degree is the main driving factors.With the increase of human interference,landscape lost diversity and tend to simplification.The results of the study on the mining area provide certain data support and theoretical basis to environment management.

Since the introduction of the Circular Economy in the 1990s,the management practice of circular agriculture has been rapid advancement.Based on the principles of sustainable agricultural development,circular agriculture has been the subject of numerous reports,which have evaluated and studied the development of this new agricultural practice at different scales.However,one of the most widely used methods of accounting for different forms of energy and resources—the emergy theory—has yet to be employed in evaluating circular agriculture.Emergy describes one kind of available energy that is used up in transformation,directly or indirectly,to make a product.It measures quality differences between forms of energy that are generated by transformation processes in nature,and that support work in natural or human dominated systems.In this study,the emergy analysis method was partly modified and specifically tailored for circular agriculture systems,and then used to evaluate the sustainability and economic benefits of ecosystem development.To validate the feasibility and quality of the improved emergy analysis method,we conducted assessments in four complex circular systems at Xingyuan circular agriculture demonstration site in the city of Fuqing,Fujian Province.We found that total production input could be substantially overestimated under the traditional emergy theory,as the systematic feedback emergy was accounted into total inputs.Further,the environmental stresses from the tremendous amount of wastes generated in the studied systems were not considered in the traditional emergy theory,and as a result,the sustainability of the conventional 'pig-only' farm was estimated to be 2.8%—11.52% higher than that of the studied circular systems.In contrast,the improved emergy analysis method could evaluate the sustainability of the circular systems more efficiently and accurately,as the most important advantage of circular agriculture—decreasing the total inputs and reducing environmental stresses by converting the systematic wastes into renewable resources—were factored into the new analysis.Furthermore,the improved emergy theory recognized the circular system as a whole by carefully defining the boundary conditions and energy fluxes in and out of the system,which reflects the real production processes both by design and in practice.According to our evaluation using the improved emergy method,the emergy sustainable indices(ESI) of the circular systems were improved by 23.44%—33.86% compared to that of conventional pig farming.The circular system of 'pig farm-biogas system-compost production-cultivation′ had the highest overall benefit among the four circular systems,as demonstrated by the highest ESI,lowest environment load ratio(ELR),and second highest emergy yield ratio(EYR),which was only slightly smaller than that of the circulating system of 'pig farm-biogas system-cultivation′.The circular agricultural system is essentially an interactive combination of multiple sub-systems.Its ecological benefits should be measured by the system efficiency rather than the length of the production chain.This is supported by our evaluation using the modified emergy theory: the 'pig farm-fire damp-compost production-mushroom farm-cultivation′ system,with the longest chain in all four studied systems,had the least ecological benefits.Further investigations into the model efficiency are required to improve flexibility and applicability of the improved emergy theory in larger areas or more complex systems.