High semi‐natural vegetation cover and heterogeneity of field sizes promote bird beta‐diversity at larger scales in Ethiopian Highlands

Abstract

1. The intensification of farming practices exerts detrimental effects on biodiversity. Most research has focused on declines in species richness at local scales (alpha-diversity) although species loss is exacerbated by biotic homogenization that operates at larger scales (i.e. affecting beta-diversity). The majority of studies have been conducted in temperate, industrialized countries while tropical areas remain poorly studied. Agricultural landscapes of sub-Saharan Africa are still largely dominated by small-scale subsistence farming, but strenuous efforts to intensify farming practices are currently spreading to meet a growing food demand. It is therefore crucial to understand how these intensified practices affect biodiversity to mitigate their negative impacts.2. We investigated how farming system (small-vs. large-scale farming) and landscape complexity (semi-natural vegetation cover) drive bird species composition, community turnover and beta-diversity patterns in Ethiopian Highlands' agroecosystems. We evaluated the following hypotheses: (1) large-scale farming homogenizes bird communities, (2) community turnover is higher in smallscale farms, (3) interactive effects between landscape complexity and farming systems shape avian communities and (4) heterogeneity of field sizes increases community turnover at larger scales.3. Bird communities underwent greater compositional changes along the landscape complexity than along the agricultural intensity gradient. Contrary to our expectations, beta-diversity was not significantly lower within large-scale farms (no biotic homogenization), and complex landscapes that still offer a high amount of semi-natural vegetation promoted community turnover in both farming systems.4. Semi-natural vegetation cover mediated how avian communities responded to agricultural intensification: the compositional differences between small-and

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“…All of the new records were made in disturbed habitats, suggesting a degree of tolerance of at least some anthropogenic disturbance. Our results are thus in accord with other reports (Wang et al 2022) that suggest human-dominated landscapes support high avifaunal diversity (Aerts et al 2008), especially in structurally complex farmland (Otieno et al 2011, Gove et al 2013, Marcacci et al 2022. As found by Gove et al (2008) and Buechley et al (2015) small-scale mixed plantations of coffee and khat also harbour high species diversity in our study area.…”

A consolidated checklist and new avifaunal records for southern Tigray, Ethiopia

“…All of the new records were made in disturbed habitats, suggesting a degree of tolerance of at least some anthropogenic disturbance. Our results are thus in accord with other reports (Wang et al 2022) that suggest human-dominated landscapes support high avifaunal diversity (Aerts et al 2008), especially in structurally complex farmland (Otieno et al 2011, Gove et al 2013, Marcacci et al 2022. As found by Gove et al (2008) and Buechley et al (2015) small-scale mixed plantations of coffee and khat also harbour high species diversity in our study area.…”

Urbanization alters the spatiotemporal dynamics of plant–pollinator networks in a tropical megacity

“…We therefore used a null model approach to calculate standardized effect sizes (z-scores) of plant, bee, and plantpollinator interaction β-diversity that allow comparisons of communities with different species richness and networks of different sizes (Dormann et al, 2009). To this end, we used a null model approach used for β-diversity within a single trophic level following Ponisio et al (2016) and Marcacci, Gremion, et al (2022) and adapted it for interaction networks (see White et al, 2022). Specifically, we created 1000 randomly assembled communities (with plant-pollinator interactions instead of species for interaction networks), maintaining species/interaction richness and abundances/frequencies (column and row sums) and drawing species/interactions with probabilities proportional to their relative abundance/frequency from the observed community.…”