From mixtures to monocultures: Bird assemblage responses along a production forest conifer-broadleaf gradient

FOREST ECOLOGY AND MANAGEMENT

卷:494

Article

Felton, Adam¹  Hedwall, Per-Ola¹  Trubins, Renats¹  Lagerstedt, Jakob¹  Felton, Annika¹  Lindbladh, Matts¹ 

[1] Swedish Univ Agr Sci, Southern Swedish Forest Res Ctr, Box 49, S-23053 Alnarp, Sweden

关键词: Mixed species stands;    Forest biodiversity;    Bird conservation;    Managed forest;    Broadleaved forest;   

DOI  :  10.1016/j.foreco.2021.119299

来源: Elsevier

【 摘 要 】

Increasing the prevalence of broadleaf trees in conifer-dominated production forests is a recommended means of improving habitat availability for broadleaf and mixed-forest species. The implications for biodiversity are often measured by contrasting broadleaf-conifer mixtures with conifer-dominated stands. However, few studies include broadleaf-dominated stands in these assessments. Here we contrasted the bird assemblages of even-aged production forests along a mixture gradient from Norway spruce (Picea abies) dominated, to birch (Betula spp.) dominated stands in southern Sweden. We conducted point count surveys of bird individuals exhibiting breeding behaviour within 30 stands varying from <0.5% to over 98.5% broadleaf by basal area. A total of 355 birds were detected, comprising 36 bird species, seven of which are classified as near threatened by the Swedish Red-list. Our results indicate i) a distinct shift in bird community composition linked to the percentage of broadleaf trees at stand and landscape scales, ii) significantly higher bird species richness, evenness, and abundance in stands with a higher proportion of birch, iii) higher bird abundance in birch-dominated stands than in mixtures, and iv) shifts in bird species guilds as related to stand basal area, the amount of shrubs in the understory, and quantities of dead wood. All of these results have implications for the ways in which production forest management could be altered to enhance avian diversity, and we discuss these with respect to the use of broadleaf versus mixed-species stands.

【 授权许可】

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