The Calculation and Analysis of Ecological Footprints of Gansu Province

Because humans consume the products and services of nature, every one of us has an impact on the earth. Does the human load stay within global carrying capacity? The ecological footprint concept has been designed to answer this question and estimate man's impact on nature. The ecological footprint of any defined population (from a single individual to a whole city or country) is the total area of ecologically productive land and water occupied exclusively to produce all the resources consumed and to assimilate all the wastes generated by population. The ecological footprint method presents a simple framework for national natural capital accounting. The concept of ecological footprint and its calculation method is introduced in this paper. The paper also analyses the advantages and disadvantages of the ecological footprint model, and addresses the types of ecologically productive lands. The article calculates and analyses the ecological footprint of Gansu province in 1998. The ecological footprint ledger is composed of three main section. The first ledger is basic biotic resources consumption including its byproducts, the second is energy consumption, the third is trade balance. Trade balance through more detailed trade flow analyses can mitigate the influence of import and export product on consumption variations. Based on the ecological footprint concept and analysis framework, human consumption can be compared with regional level natural capital production using existing data. In the case of Gansu province, the ecological deficit of Gansu is 0 564 2 hm 2 per capita. Simplification of calculation methodology to certain extent results in over optimistic estimates. Finally, the ecological footprint model's advantages and disadvantages are identified. Ecological footprint index is an excellent aggregate index that connects many issues of sustainability, development and equity. The model can reveal the extent to which local carrying capacity has been exceeded and allows a cumulative approach to impact analysis. The use of ecological productive area as a numeraire, rather than money or energy, makes the footprints easy to be understood, and also permits provocative calculations. The limitations of the model is that it doesn't include several important issues, which are even directly related to land use: land areas lost to biological productivity loss of land because of contamination, erosion and urban “hardening” and dissertation (especially in north western China). Methodologically, the assessments could be more complete by including the ecological spaces used for freshwater use, a particular important issue in arid area of north western China.