Emergy evaluation of the artificial forest ecosystems in the watershed of Miyun Reservoir:a case study for ecosystems valuation and environmental management

To build the artificial forest ecosystem is the major eco-economic development model in the watershed of Miyun Reservoir. It is very important to evaluate the benefits of those ecosystems. Emergy theories are very helpful for us to establish a science-based assessment framework. Emergy evaluation of the artificial forest ecosystems in the watershed of Miyun Reservoir is used to asses the relative values of several ecological functions (sometimes called ecosystem services) and main ecosystem storages (sometimes called natural capital). The main driving energies, internal processes and storages are evaluated. The main functions, including transpiration, GPP and infiltration, are evaluated, which are 609em$/ha/yr, 6,245em$/ha/yr and 340em$/ha/yr respectively. The total values of major environmental services are 4,683em$/ha/yr in the artificial forest ecosystem. The main storages of natural capital including live biomass, soil moisture, organic matter, underground water and landform are estimated, which are 112,028em$/ha, 9em$/ha, 40,718em$/ha, 34em$/ha and 6,400,514em$/ha respectively. The largest value is landform, which accounts for 97.7% of these calculated total emdollar values. The concept of replacement value is explored using the emergy values of both ecosystem services and natural capital. The total calculated replacement values are 302,160em$/ha.

Emergy Evaluation of Treatment Methods for Solid Medical Waste in Bujumbura-Burundi

Introduction: Treatment of solid medical waste (SMW) is a complex task requiring the proper practices with specific treatment methods corresponding to each type of SMW during pretreatment and final treatment. This study targeted three treatment methods identified as the main used by the majority of health care facilities (HCFs) and treating a large amount of SMW. It aimed: 1) to evaluate the current practices by calculating the emergy investment and emergy costs that are required to treat one ton of SMW through the three treatment methods and 2) to evaluate and compare better technologies and provide policy suggestions for the final treatment of SMW in Burundi. Materials and Methods: This study used the emergy methodology to evaluate the relative efficiencies of three treatment methods used for to treat SMW in twelve HCFs in Bujumbura. Results and Conclusion: The total emergy input was 1.36E+20 seJ/yr, 3.54E+17 seJ/yr, and 1.681E+18 seJ/yr for low temperature incinerator, landfill and organic pit, respectively. Conclusion: Rapid improvement of organic pit by ensuring its maintenance, the gradual replacement of low temperature incinerator by high temperature incinerator with air control pollution and landfill by sanitary landfill are highly recommended by respecting its maintenance (fence, roof and monitoring evaluation) for reducing the risk.

Evaluation and advancement of the integrated circular economy model of farming and stock raising

The integrated circular economy model of farming and stock raising(ICEMFSR)has attracted increased attention as an effective model for solving the current irrational allocation of agricultural resources and realizing the agricultural value-added industrial chain.This study uses emergy analysis to comprehensively examine and evaluate the economic benefits,environmental pressures,and sustainable development levels of ICEMFSR in Shucheng County,China.The results show that the ICEMFSR possesses the value of popularization with optimally allocated resources in the studied region,in which the emergy yield ratio(EYR),emergy loading ratio(ELR),and emergy sustainable index(ESI)in this model accounted for 3.59,1.25,and 2.89,respectively.This result indicates a leading position in the national agricultural system.Hence,this study constructs a new model based on the coupling of emergy evaluation and multi-objective linear programming to study ICEMFSR.Consequently,the EYR,ELR,and ESI respectively varied by +24.23%,10.40%,and +38.06%after replanning of ICEMFSR.This variation implies a significant improvement in the sustainable development level of the model.In addition,the optimized scenario design for key substances is proposed based on traceability and the reduce-reuse-recycle principle,including biogasification of crop straw and enhancement of crop scientific planting capacity.

Changes in paddy cropping system enhanced economic profit and ecological sustainability in central China

In China,the traditional early and late season double rice(DR)system is declining accompanied by the fast increase of two newly developed cropping systems:ratoon rice(RR)and rice-crawfish(RC).Three methodologies:economic analysis,emergy evaluation and life cycle assessment(LCA)were employed to evaluate the economics and sustainability of this paddy cropping system change.Economic analysis indicated that the income and profit of the RC system were far larger than those of RR and DR.The income to costs ratio of RR and RC increased by 25.5 and 122.7%compared with that of DR,respectively.RC had the highest emergy input thanks to increasing irrigation water,electricity,juvenile crawfish and forage input while RR showed a lower total emergy and nonrenewable emergy input,such as irrigation water,electricity,fertilizers and pesticides than DR.The environmental loading ratios decreased by 16.7-50.4%when cropping system changed from DR to RR or from DR to RC while the emergy sustainability indexes increased by 22.6-112.9%.The life cycle assessment indicated lower potential environmental impacts of RR and RC,whose total environmental impact indexes were 35.0-61.0%lower than that of DR.Grain yield of RR was comparable with that of DR in spite of less financial and emergy input of RR,but RC had a much lower grain yield(a 53.6%reduction compared to DR).These results suggested that RR is a suitable cropping system to achieve the food security,economic and environmental goals.