Emergy-based Analysis Of Under-forestry Economy System In Yellow River Delta

Under-forestry Economic is a form of land utilization type which widely exists inagricultural practice. It,s based on the ecology principle, according to the technical and thelaw of economic demand, builder up a species population, multiple levels, multiple sequences,multiple functions, multiple benefits, high productive, efficient, continuous and stableproduction system. Which is a complex open system based on the forest, improved the landutilization efficiency and promote the recycling of material flows with energy flows in thesystem to implements the efficiency operation. In recent years, the construction ofunder-forestry economic industry was treated which as an important way to promoteecological protection, increasing farmers’ income, speed up social development by the city ofDongying, and significant results were achieved by developing the under-forestry economic.This research using emergy theory and method, make analysis and evaluation of agroforestrysystem of demonstration base of provincial forest, which lies in Guangrao County ofShandong Province, Dongying City. Through making emergy analysis table, drawing emergysynthesis system diagram, building energy analysis index system to give some suggestionsabout improving functional structure and sustainable development in order to realizing themaximization of the ecological and economic benefits.Using emergy theory and analysis method, this paper made analysis about input andoutput of the under-forestry economic system in Guangrao. Six indicators that includedrenewable resources/environmental resources value, non-renewable resources/total input,emergy investment ratio, net emergy yield ratio, environmental loading ratio, emergy indexfor sustainable development are selected for making quantitative analysis about thesustainability of different models of under-forestry economic.Through analysis andcomparative finding the problems and give matching advice and suggestions, by emergyanalysis, we draw the following conclusions:(1) In four modes of the under-forestry economic system, the highest emergy investmentratio is the mode of Polar-Platycodon grandiflorum-Salvia Miltiorrhiza Bunge rotation,5.369in2011and23.391in2012, both of them higher than agricultural ecosystem in Shandongprovince that was3.76in2003, and the other three models are lower than the average standard of Shandong province, it suggested that the systems are at the initial stage ofdevelopment, in order to promote the sustained and rapid development of the system, whichneeds to be improved and adjusted, also to increase the input of the purchased emergy.Thehighest net emergy yield ratio in the four modes is Polar--Salvia Miltiorrhiza Bungecontinuous cropping, the rates were25.8974in2011and22.5238in2012, it shows that thismode has the highest production efficiency, in the other word, under the condition of the sameemergy input which can obtain more emergy output so that the production to be morecompetitive in the market. The other three mode,s net emergy yield ratio were higher thanthe average of Shandong province which was5.31in2003, but these system still need to beoptimized, achieve the purpose of further improve the output efficiency of the system. Themode of Polar-Platycodon grandiflorum-Salvia Miltiorrhiza Bunge rotation has the highestenvironmental loading ratio,8.1653in2011,38.0320in2012, what were far higher than theaverage level of Shandong which was6.42in2003, especially, it caused considerableenvironmental pressure in the development of2012, and its output was at the cost of highconsumption of natural resources. Obvious the structure was not reasonable, so the system,ssustainability was very low. The environmental loading ratio was only0.2841in2012, systemstructure absolutely needs rectification. The mode of Polar-Salvia Miltiorrhiza Bunge,semergy index for sustainable development was11.96in2011, its a little high, the system is inthe stage of expense, but the index reduced to5.0821in2012, it shows that after theadjustment the system has effectively changed on Sustainability and development potential.So, in a nutshell, reasonable structure of input and output, scientific human management willbenefit to the health and sustainable development of the system. It,s the only way to balancethe development and ecological environment protection with express efficiency enough of thesystem.(2) The under-forestry economy development we should pay attention to soil and waterconservation at the same time. The research area is located in Improvement of saline-alkaliarea of the Yellow River Delta, with relatively poor soil conditions. From the emergy analysistable, we can see that the surface soil loss of the total investment for an average about10%. Inorder to avoid further deterioration of soil conditions, we must pay more attention to waterand soil conservation, increase the amount of organic fertilizer application, enhance human management and prevent water and soil from going away.(3)The optimal mode is Poplar-salvia miltiorrhiza in the region,s existing models, therenewable resources input and non-renewable input were at reasonable level, the system wasactive and has sustainable development, in total this model was better than others, but therewere many problems in the system development, such as the density of the crops should bereasonable configuration, avoid the soil over nutrient consumption in a short period, reserveenough wide belt for the three to make sure it can grows healthily, increase the organicemergy inputs, strengthen the cultivation and management, enhance the investment inscience and technology, further improve the system net emergy yield. At the same time weshould focus on the protection of the natural environment in development, reduce theproportion of nonrenewable purchase emergy investment, drop the environmental loading ratedown, thus improving the overall operating efficiency of the system in order to achieve themaximization of the ecological and economic benefits.