title: Accounting for ecosystem alteration doubles estimates of conservation risk in the conterminous United States.
abstract: Previous national and global conservation assessments have relied on habitat conversion data to quantify conservation risk. However, in addition to habitat conversion to crop production or urban uses, ecosystem alteration (e.g., from logging, conversion to plantations, biological invasion, or fire suppression) is a large source of conservation risk. We add data quantifying ecosystem alteration on unconverted lands to arrive at a more accurate depiction of conservation risk for the conterminous United States. We quantify ecosystem alteration using a recent national assessment based on remote sensing of current vegetation compared with modeled reference natural vegetation conditions. Highly altered (but not converted) ecosystems comprise 23% of the conterminous United States, such that the number of critically endangered ecoregions in the United States is 156% higher than when calculated using habitat conversion data alone. Increased attention to natural resource management will be essential to address widespread ecosystem alteration and reduce conservation risk.
authors.affiliation: The Nature Conservancy, Marquette, Michigan, United States of America. rswaty@tnc.org
authors.forename: Randy
authors.initials: R
authors.lastname: Swaty
authors.forename: Kori
authors.initials: K
authors.lastname: Blankenship
authors.forename: Sarah
authors.initials: S
authors.lastname: Hagen
authors.forename: Joseph
authors.initials: J
authors.lastname: Fargione
authors.forename: Jim
authors.initials: J
authors.lastname: Smith
authors.forename: Jeannie
authors.initials: J
authors.lastname: Patton
mesh_terms: D017753:Ecosystem; D005843:Geography; D014481:United States