title: Functional roles affect diversity-succession relationships for boreal beetles.
abstract: Species diversity commonly increases with succession and this relationship is an important justification for conserving large areas of old-growth habitats. However, species with different ecological roles respond differently to succession. We examined the relationship between a range of diversity measures and time since disturbance for boreal forest beetles collected over a 285 year forest chronosequence. We compared responses of "functional" groups related to threat status, dependence on dead wood habitats, diet and the type of trap in which they were collected (indicative of the breadth of ecologies of species). We examined fits of commonly used rank-abundance models for each age class and traditional and derived diversity indices. Rank abundance distributions were closest to the Zipf-Mandelbrot distribution, suggesting little role for competition in structuring most assemblages. Diversity measures for most functional groups increased with succession, but differences in slopes were common. Evenness declined with succession; more so for red-listed species than common species. Saproxylic species increased in diversity with succession while non-saproxylic species did not. Slopes for fungivores were steeper than other diet groups, while detritivores were not strongly affected by succession. Species trapped using emergence traps (log specialists) responded more weakly to succession than those trapped using flight intercept traps (representing a broader set of ecologies). Species associated with microhabitats that accumulate with succession (fungi and dead wood) thus showed the strongest diversity responses to succession. These clear differences between functional group responses to forest succession should be considered in planning landscapes for optimum conservation value, particularly functional resilience.
authors: Department of Zoology, La Trobe University, Melbourne, Victoria, Australia. h.gibb@latrobe.edu.au
authors: Heloise
authors: H
authors: Gibb
authors: Therese
authors: T
authors: Johansson
authors: Fredrik
authors: F
authors: Stenbacka
authors: Joakim
authors: J
authors: Hjältén
mesh_terms: D000818:Animals; D044822:Biodiversity; D001517:Coleoptera / Q000502:physiology*; D008962:Models, Theoretical; D012044:Regression Analysis; D013045:Species Specificity; D013548:Sweden
references: Ecol Lett. 2006 Jan;9(1):15-23
references: 16958864
references: Ecology. 2011 Oct;92(10):1871-8
references: 22073777
references: Oecologia. 1980 Jul;46(1):18-21
references: 28310620
references: Science. 1978 Mar 24;199(4335):1302-10
references: 17840770
references: Science. 1965 Jan 15;147(3655):250-60
references: 17788203
references: Ecol Lett. 2007 Oct;10(10):995-1015
references: 17845298
references: Ecol Appl. 2010 Dec;20(8):2310-21
references: 21265460
references: Ecology. 2006 May;87(5):1075-85
references: 16761584
references: Ecol Appl. 2006 Jun;16(3):901-12
references: 16826990