"biodiversity is easily affordable" - what does this mean?

Biodiversity is simple, preserve natural habitats in contiguous tracts. Development tends to sprawl which destroying habitat. If we maximized footprints already developed by going vertical, then much of the outlying area could be protected. High rise residential towers are popular in some major cities along with mixed use developments. Governments and organizations must work together to strategically secure land and restrict development rights in order to sustain natural ecosystems. The more habitat converted to human manipulated land uses will put additional strain on species and make it that much harder to bolster struggling populations of endangered species.

"A major cause for concern is that 34 of the 38 AEWA species, which feature on the IUCN Red List of threatened species occur in Africa. Moreover, 13.3% of all AEWA populations occurring in Africa are classified as Globally Threatened or Near Threatened in the IUCN Red List, compared to 7.3% in Europe and 11.5% in Asia." This money could be used to help this situation. There's more information here: http://www.unep-aewa.org/activities/africaninitiative.htm