Emergy ecological footprint method considering uncertainty and its application in evaluating marine ranching resources and environmental carrying capacity

Abstract

The emergy ecological footprint method is an effective tool to evaluate resources and environmental carrying capacity (RECC) given its advantages of objectivity and ease of comparison with. However, the uncertainty in the emergy ecological footprint calculation reduces the credibility of the evaluation results of this method. Combining the emergy system analysis of marine ranching and the accounting rules of the emergy ecological footprint model, this study analyzed the sources of uncertainty in marine ranching RECC evaluation by the emergy ecological footprint model. Based on Dempster–Shafer evidence theory, the uncertainty in the original model was reduced by introducing expert experience, and an emergy ecological footprint method considering uncertainty was constructed. The modified method was applied to RECC evaluation of marine ranching in Yantai, China, and the results showed that the marine ranching was in a safe state. Furthermore, the sensitivity analysis identified the uncertainty of each evaluation index, revealing that the improvement of the relevant data quality of artificial reef indexes, whose uncertainty accounted for more than 95%, was crucial to obtaining more reliable evaluation results of marine ranching RECC. Considering the imprecision and incompleteness of data statistics and complexity of systems, the proposed modified method is important in improving the reliability of RECC evaluation of various micro- and meso-level eco-economic systems except for marine ranching.