Biocapacity (BC) measures the bioproductive supply that is available within a certain area (e.g. of arable land, pasture, forest, productive sea).
The biocapacity (BC) is a method to answer the question: "How many of the renewable resources have been made available by the biosphere’s regenerative capacity (are produced by the various ecosystems)?" BC represents the bulk of the biosphere’s regenerative capacity. It is an aggregate of the production of various ecosystems in a certain area (e.g. of arable land, pasture, forest, productive sea). Some of it may also consist of built up or degraded land. The earth’s BC increases with a larger biologically productive area and with a higher productivity per unit area.
BC is usually presented together with Ecological Footprint (EF), which measures the extent to which humanity is using nature’s resources faster than they can regenerate. The mathematical difference between EF and BC is called either reserve or deficit (or overshoot for the globe).
EF and BC are tantamount to the concepts demand and supply in Economics. When used together, they form the EF/BC accounts. "EF/BC accounting" is frequently referred to only as "EF accounting"
Eurostat, "Ecological Footprint and Biocapacity: The world's ability to regenerate resources and absorb waste in a limited time period", Working Papers and Studies, Office for Official Publications of the European Communities, Luxembourg, 2006