| Emergy analysis for the study of ecological and economic system opens up newquantitative analysis methods. By Emergy analysis method can be constructed emergyratio, emergy self-sufficiency rate, net emergy yield ratio, environmental loadingratio,,emergy sustainable development index and so on, which can reflect the index systemof a series of eco-economic system structure and function. This paper analyzes the inputand output of emergy of Dingxi agricultural eco-economic system from two aspects ofstatic (2012) and dynamic(2003to2012) using Emergy theory and methods, andestablishes an index system which can be able to reflect the structure and function of thevalue of the evaluation system.In terms of a series of problems in agricultural productionin Dingxi City, this paper proposes the corresponding countermeasures and suggestions.By static and dynamic analysis of Dingxi agricultural eco-economic system can we get thefollowing conclusions:（1）The total investment value of Dingxi agricultural eco-economic system in2012is5.47E+21sej, and the total output is4.31E+21sej. The total investment value is madeup of4parts:the value of renewable Emergy resources, the value of non-renewableresources, the value of non-renewable auxiliary Emergy, the value of renewable Emergy,and the respective input were1.70E+21sej,2.46E+21sej,1.91E+21sej,1.61E+21sej,and the proportion of total input Emergy values were31.08%,4.50%,34.92%,29.43%.The important parts of the value of non-renewable resources were the emergy of fertilizerand mechanical Emergy value,and the value of input were1.74E+21sej,1.60E+21sej,and the proportion were91.10%,8.38%. In the proportion of input of renewable Emergy,the input emergy of labor and animal can be accounted for98.08%, while the input oforganic fertilizer is low. Emergy of output is made up of the Emergy of farming, animalhusbandry, forestry and the fishery, and the output Emergy values were2.23E+21sej,1.30E+21sej,7.51E+20sej,2.94E+19sej, and the proportion of the total value of outputEmergy were51.74%,30.16%,17.42%,0.68%.The proportion of farming emergy ishighest, and the livestock, forestry is an important component, but fisheries is less than1%. (2) The value of the conversion of solar Emergy systems of Dingxi agriculturaleco-economic system in2012was1.27, and the Emergy level and the value effect is lowe.And the output of Emergy was1.81, higher than the national average (1.11), but lower thanthe average level in Gansu province (2.08), and the degree of exploitation of local naturalresources is low. Emergy self-sufficiency rate of0.36is at a relatively high leveldemonstrating a large dependence on the environment. Net Emergy output was1.22, lowervalues into secondary Emergy utilization efficiency, the system productivity. The emergyof renewable resources is0.61, and the potential of system is large. The emergy ofnonrenewable Emergy resources is0.39indicating less pressure on the environment.Theload rate of Environmental was2.22, indicating less pressure on the environment, but alsoexplaining the lower utilization of environmental resources. Emergy Sustainability Indexwas0.55,and the system is a consumer-based economy system, and the sustainability of thesystem is not high.(3) During2003and2012, the total input and output of agricultural eco-economicsystem in Dingxi showed a growth trend. The increase comes mainly from non-renewableEmergy growth. The input of nonrenewable auxiliary grew from the value of1.45E+21sej rose to1.91E+21sej, representing the proportion of auxiliary Emergy values rose from48.01percent to54.26percent, especially nitrogen, phosphate, potash, fertilizers andfertilizer-based values into mechanical Emergy grew faster. The proportion of the input ofrenewable Emergy in auxiliary Emergy value showed overall downward heavy trend,falling from51.99%in2003to45.74%in2012. In the growth of the total Emergyyield,the growth of crop and livestock were more obvious, and the increases are as follows:54.39%,56.94%. Forestry emergy showedfluctuating downward trend and the output offishery remains low.(4) During2003and2012, the rate of input of agricultural eco-economic system inDingxi showed fluctuating upward trend, indicating that the level of economicdevelopment has increased, but the system is unstable. The rate of Emergy self-sufficiencyfluctuates heavily and showed the overall downward trend, indicating that dependence onthe environment.is reducing. The rate of net Emergy yield showed overall downward trend,indicating that the production efficiency of the system decreased, resulting in a lower market competitiveness of agricultural products.The value of the conversion rate of theSolar System slight fluctuatesd between1.24-1.30, showing insignificant upward ordownward trend, indicating a low level of Emergy value and effect of the system and isrelatively stable. The emergy of renewable resources showed the overall downward trend,indicating that the potential of the environment that can be utilized is declining; while theemergy of non-renewable Emergy resources showed the overall showed a trend comparedto the total, indicating that the pressure on agricultural production system environmentincreases.(5) During2003and2012, the environmental loading ratio of agriculturaleco-economic system in Dingxi showed overall upward trend, indicating that as the inputof non-renewable emergy increases, the level of utilization of the system is alsoincreasing,while the pressure on environment increases. Emergy Sustainability Indexdeclined and ESI <1, indicating that the system is a consumer-based economy system.Inthe agricultural production process, we have not only to protect the environment, but alsoimprove the utilization of environmental resources, and we should take effectivemeasures to increase sustainable development capacity of the system. |
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