Carrying capacity using emergy and a new calculation of the ecological footprint

Abstract Carrying capacity was evaluated using emergy assessment to improve the diagnosis of problems and to make understanding sustainability easier, thereby supporting the formulation of public policies. Ibiuna County has an area of 105,800 hectare (ha) and it is located 72 km west of Sao Paulo, the largest Brazilian city. It has 72,029 inhabitants or 0.68 people per ha, but 2.16 people per ha of forest area. The city is only 157 years old and about 67% of its population lives in the rural area and the other 33% in the urban space. In our assessment, the percent renewability of this municipality was high (47.20%). To determine the renewable support area, the carrying capacity methodology suggested by Brown and Ulgiati (2001) was applied and the support area calculated was 306,679 ha or 0.23 people per ha. This result reveals a value for the equivalent natural area needed to absorb the impacts of the fossil fuel consumed in the production of industrial inputs used in the region. A recently proposed ecological footprint methodology was used, where the calculus of support area is based on the consumption profile of the population. This methodology was adapted to obtain an alternate carrying capacity for the county. The result was 249,650 ha or 0.29 individuals per ha. This study showed the importance of preserving natural areas and it introduced the need for changes in the configuration of the county economy and in its population's lifestyle, which are needed to turn Ibiuna County into a truly sustainable region.