Don’t Despair, Repair

Nature recovers from damage sooner than expected
Journal Watch Online 29 May 09;

Be skeptical of frequent claims that humans are doing irreparable harm to our environment that will take centuries or millennia to repair. Two Yale University researchers compiled 240 independent studies of polluted or damaged ecosystems and came to what they call a startling conclusion: once humans committed to their restoration, most ecosystems healed within a matter of decades.

Eighty-three of the ecosystems analyzed by these studies showed full recovery for variables representing ecosystem function, animal community and plant community health; 90 had mixed results, 67 showed no recovery, the PLoS ONE study found.

Forests took the longest to recover, an average of 42 years, while many aquatic systems needed between 10 and 20 years. Meanwhile around a half a century was needed to mend ecosystems harmed by agriculture or a multiplicity of threats, whereas the effects of oil spills, trawling, invasive species, and mining were reversed in less than a decade.

The authors say their study redeems the value of restoration to those who would monger visions of doom and insist on chronicling ecosystem destruction in hopes of banning all human activity in “natural” areas. “Our results are not intended to give license to exploit ecosystems without regard to sustainability,” they write. “The message of our paper is that recovery is possible and can be rapid for many ecosystems, giving much hope for humankind to transition to sustainable management of global ecosystems.” – Jessica Leber

Source: Jones, H.P. and Schmitz, O.J. et al. 2009. Rapid Recovery of Damaged Ecosystems. PLoS ONE DOI: 10.1371/journal.pone.0005653