Abstract
Native forests are shrinking worldwide, causing a loss of biological diversity. Our ability to prioritize forest conservation actions is hampered by a lack of information about the relative impacts of different types of forest loss on biodiversity. In particular, we lack rigorous comparisons of the effects of clearing forests for tree plantations and for human settlements, two leading causes of deforestation worldwide. We compared avian diversity in forests, plantations and exurban areas on the Cumberland Plateau, USA, an area of global importance for biodiversity. By combining field surveys with digital habitat databases, and then analyzing diversity at multiple scales, we found that plantations had lower diversity and fewer conservation priority species than did other habitats. Exurban areas had higher diversity than did native forests, but native forests outscored exurban areas for some measures of conservation priority. Overall therefore, pine plantations had impoverished avian communities relative to both native forests and to exurban areas. Thus, reports on the status of forests give misleading signals about biological diversity when they include plantations in their estimates of forest cover but exclude forested areas in which humans live. Likewise, forest conservation programs should downgrade incentives for plantations and should include settled areas within their purview.
Highlights
Few studies have compared the effects of timber extraction, human settlement or agriculture within one landscape using a standardized methodology that allows statistically rigorous assessments of the relative impacts of different types of forest loss
A similar pattern emerged at the level of individual counts, except that native forests did not differ from mid-aged pine plantations in the number of species detected per count (Figure S2, Table S2)
Evenness measured at the scale of habitat classes was highest in exurban areas, followed by thinned native forests, native forests, all age-classes of pine plantation (Figure 2)
Summary
Human settlement, clearing for agriculture, and conversion of forests to tree plantations account for most of these declines [1] This loss of natural systems has resulted in declines in biodiversity and degradation of ecosystem services formerly provided by the forests [2]. In response to these declines, many governments and private agencies have put into place forest conservation and management initiatives [3,4]. Few studies have compared the effects of timber extraction, human settlement or agriculture within one landscape using a standardized methodology that allows statistically rigorous assessments of the relative impacts of different types of forest loss. Because forests are usually subject to losses from multiple sources, such broad-level comparisons are a prerequisite to informed conservation planning
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
