the review recommended the prioritization of accounting principles that provide consistent consideration of natural disturbance regimes temporal scales and system boundaries in contrast an extensive study of the status and future potential of global bioenergy resources systems and markets scope suggested that as much as of the worlds fuel supply could be biobased by although it also found that the implementation of successful bioenergy production systems will require clear sustainability metrics and monitoring programmes stable land tenure and effective local and national governance conditions not yet established in many countries this was an increase of million hectares over the previous months although the increase was about million hectares less than that seen in the preceding month period in the caseof the pefc data are reported to december and more forest may have been certified to may more than of the double certification is in europe million hectares and north america million hectares