Abstract
In the present paper, quantitative evaluation of human activity in the entire basins of three major bays of Japan was made using ecological footprint (EF) analysis. The analysis is a tool to assess sustainability of a region by comparing EF which is the biologically-productive area required to sustain human activity with the actual area of that as biocapacity. The basins of Tokyo Bay, Ise Bay and Osaka Bay have regional footprint of 36.6, 24.7, 22.3 million gha and the ratios of EF to biocapacity of 58.2, 10.5 and 25.0, respectively. The Tokyo Bay basin has the largest EF and extreme ratio, but the EF per capita is smallest in the three bay basins. It shows the human activity in the basin is environmental-economically efficient but poor cycle system of biological product. Employing EF analysis, Phosphorus Footprints (PF) in the basins are calculated and supply-demand balance of phosphorus is evaluated. PF are 16.0×106 kg, 6.9×106 kg and 8.3×106 kg, and PF-capacity ratios are 6.6, 1.7 and 3.9 in the Tokyo Bay, Ise Bay and Osaka Bay basins respectively. Ripple effect of 50 % increase of fish catches on EF and PF is decrease of EF with 0.24 to 0.77%, PF ratio with 0.45 to 1.46%.
