Conserving and promoting evenness: organic farming and fire-based wildland management as case studies

Crowder, David W., Northfield, Tobin D., Gomulkiewicz, Richard, and Snyder, William E. (2012) Conserving and promoting evenness: organic farming and fire-based wildland management as case studies. Ecology, 93 (9). pp. 2001-2007.

PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (6MB)
View at Publisher Website:


Healthy ecosystems include many species (high richness) with similar abundances (high evenness). Thus, both aspects of biodiversity are worthy of conservation. Simultaneously conserving richness and evenness might be difficult, however, if, for example, the restoration of previously absent species to low densities brings a cost in reduced evenness. Using meta-analysis, we searched for benefits to biodiversity following adoption of two common land-management schemes: the implementation of organic practices by farmers and of controlled burning by natural-land managers. We used rarefaction to eliminate sampling bias in all of our estimates of richness and evenness. Both conservation practices significantly increased evenness and overall abundance across taxonomic classifications (arthropods, birds, non-bird vertebrates, plants, soil organisms). Evenness and richness varied independently, leading to no richness–evenness correlation and no significant overall change in richness. Demonstrating the importance of rarefaction, analyses of raw data that did not receive rarefaction indicated misleadingly strong benefits of organic agriculture and burning for richness while underestimating true gains in evenness. Both organic farming and burning favored species that were not numerically dominant, re-balancing communities as uncommon species gained individuals. Our results support the assertion that richness and evenness capture separate facets of biodiversity, each needing individual attention during conservation.

Item ID: 28143
Item Type: Article (Research - C1)
ISSN: 1939-9170
Keywords: abundance; agriculture; biodiversity; conservation; ecosystem management; evenness; fire; metadata; organic farming; species richness
Additional Information:

This article is available via Creative Commons Attribution License, which permits restricted use, distribution, and reproduction in any medium, provided the original author and sources are credited.

Date Deposited: 22 Jul 2013 05:35
FoR Codes: 06 BIOLOGICAL SCIENCES > 0602 Ecology > 060202 Community Ecology (excl Invasive Species Ecology) @ 50%
05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050202 Conservation and Biodiversity @ 50%
SEO Codes: 96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960804 Farmland, Arable Cropland and Permanent Cropland Flora, Fauna and Biodiversity @ 50%
96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960806 Forest and Woodlands Flora, Fauna and Biodiversity @ 50%
Downloads: Total: 1217
Last 12 Months: 58
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page