Emergy Analysis of Environmental Carrying Capacity for Sustainable Development Strategies of Resort Islands

Abstract

The scale of resources consumed by the growing population has continually increased. Thus, interest in the environmental carrying capacity that can accommodate resource consumption and certain activities has also increased. A region can achieve sustainable development if there is future sustainability based on the economic and social activities that occur within the environmental carrying capacity. Since islands are isolated by the sea, they lack resources, and energy flow is difficult. Thus, the environmental carrying capacity of an island region is limited. In addition, resort islands have a large tourist population in addition to resident population, so it is necessary to assess the environmental carrying capacity of these islands by taking the tourist population into consideration.

There are many ways to evaluate the environmental carrying capacity including the ecological footprint, the Onishi model, and emergy analysis. A particularly useful approach is an emergy analysis, which calculates the environmental carrying capacity by considering the energy flow. Using this method reflects the characteristics of an island where inputs and outputs can be identified. From an energy perspective, this method can also assess the environmental load caused by the development of tourism.

Several studies on the evaluation of the environmental carrying capacity using an emergy analysis have been conducted. In South Korea, the environmental carrying capacity has been assessed for each city. Analyzes have also been conducted overseas in areas such as China, Canada, Brazil, and Italy to evaluate sustainability. However, there are limits to using the findings of previous studies that have been conducted in mainland regions to reflect the characteristics of isolated island areas. Although some studies have considered tourism characteristics, there would be different results of the environmental carrying capacity in resort islands that have a higher tourist population and tourism influence.

The present study addresses this lack of research by evaluating the environmental carrying capacity of resort islands in 2015 using an emergy perspective. Chapter II discusses prior studies on this topic. Chapter III examines the characteristics of resort islands and the methodology to estimate the environmental carrying capacity. Chapter IV shows the results, and discusses the emergy evaluation, and compares the results of emergy and sustainability evaluations in three resort islands: Jeju Island, Hainan, and Hawaii. Finally, Chapter V summarizes the study results as a conclusion.

The key results of this study from 2015 are as follows. The imports emergy of Jeju Island accounted for 83% (1.75 × 1022 sej/year), while the rest comprised 11% of RE emergy (2.43 × 1021 sej/year), 5% of IR emergy (1.08 × 1021 sej/year), and 1% of EX emergy (1.76 × 1020 sej/year). The imports emergy of Hainan accounted for 52% (8.74 × 1022 sej/year), while the rest comprised 25% of IR emergy (4.22 × 1022 sej/year), 13% of EX emergy (2.18 × 1022 sej/year), and 10% of RE emergy (1.63 × 1022 sej/year). The imports emergy of Hawaii accounted for 71% (7.36 × 1022 sej/year), while the rest comprised 11% of IR emergy (1.10 × 1022 sej/year), 11% of RE emergy (1.08 × 1022 sej/year), and 7% of EX emergy (7.33 × 1021 sej/year).

Based on the evaluated emergy, the emergy indices (%Renew, EYR, ELR, SI, and CCP) were calculated and the sustainability of each region was evaluated. The %Renew (percent renewable) index was 0.73 (sustainable system) for Hawaii, 0.56 (transitional system) for Jeju Island, and 0.23 (unsustainable system) for Hainan. The EYR (emergy yield ratio) index was 3.98 (unsustainable system) for Hawaii, 2.27 (unsustainable system) for Jeju Island, and 1.30 (unsustainable system) for Hawaii. The ELR (environmental loading ratio) index was 0.36 (sustainable system) for Hawaii, 0.80 (sustainable system) for Jeju Island, and 3.35 (transitional system) for Hainan. The SI (sustainability index) was 11.02 (sustainable system) for Hawaii, 2.83 (transitional system) for Jeju Island, and 0.39 for Hainan. The CCP (carrying capacity of the population) was 1,530,000 for Hawaii, 780,000 for Jeju Island, and 12,170,000 for Hainan.

This study also proposes that the islands consider a premium tourism and a policy to utilize renewable energy. Premium tourism is expected to reduce the demand for imported emergy. Incorporating a renewable energy policy would reduce their reliance on external emergy sources. Theses policies will help improve the environmental carrying capacity of resort islands that have limited resources and must consider the tourist population.