The Risk Evaluation Of Ecological Economic System Of Gansu Province

Based on the emergy footprint, a study of the ecosystem in Gansu Province over the past 12 years is conducted through the method of ecological risk assessment. This paper encompasses the following contents:1> We calculate the ecological carrying capacity and the energy footprint of Gansu province from 2001 to 2012 using the energy footprint model. The results shows that, Per capita energy carrying capacity is from 4.84 hm2 to 6.18 hm2, and then to 5.54 hm2, showing a decreasing trend after the first increment; and Per capita energy footprint is from 3.49 hm2 to 6.33 hm2, showing a general obvious increasing trend. Among them, woodland energy footprint and construction land energy footprint presents a obvious increasing trend; farmland energy footprint, the grass energy footprint and fossil fuel land energy footprint present a slower increasing trend, and the water energy footprint presents a smaller decline trend. A fitting study on per capita energy footprint is carried out for the six categories of ecological productive land. Based on this, it forecasts this per capita development trend of the future ecosystem in Gansu province.It is expected that by 2015, the per capita energy footprin in Gansu province to 7.3248hm2. According to the results, we predict that the ecological economic system will appear ecological deficit in Gansu province.2、 We carry out risk assessment for energy footprint of Gansu province from 2001 to 2012 using the ecological risk EVR model. The results shows that, With 97.5 percent of the confidence level, for example, there’s a 97.5 percent chance in the future that the energy growth rate for a year of ecosystem services value in Gansu province won’t be 7.615 percent lower than the expectation growth rate which is 7.314 percent. In other words, there’s a 97.5 percent chance in the future that the biggest loss that ecosystem services value of Gansu province will suffer is 4.79×1020Sej. The results show that the eco economy system in Gansu province will face some risk loss.3、A linear regression model for the comprehensive ecological risk assessment is established. Through this, the impacts of the aforementioned land’s ermery loss risk towards the ecosystem’s comprehensive loss risk is analyzed and the conclusion is: The water area emergy loss risk has the biggest impact on the whole ecosystem’s comprehensive risk, while the building land emergy has the slightest impact.