Contributions of Hedgerows to People: A Global Meta-Analysis

Abstract

Hedgerows are linear landscape features of woody vegetation usually located around agricultural fields. An increasing number of studies have addressed the effects of hedgerows on biodiversity and ecosystem services. This study is aimed to synthesize these effects and compare the levels of biodiversity and ecosystem services in farmland with hedgerows and (1) farmland without hedgerows and (2) nearby natural habitat at the global scale. We hypothesized that farmland with hedgerows (1) enhances biodiversity and ecosystem services as compared to farmland without hedgerows but (2) supports lower levels of biodiversity and ecosystem services than natural habitat. Our systematic literature review retained 835 observations from 170 primary studies, which were analyzed following the standard methodology in meta-analyses. Our results partially support both hypotheses. Farmland with hedgerows exhibited higher levels of biodiversity and provisioning services than farmland without hedgerows (H1). Farmland with hedgerows provided similar levels of biodiversity (edge effects) but lower levels of ecosystem services than natural habitat (H2). The effects of hedgerows on biodiversity and ecosystem services depended on control ecosystem type (grassland/meadow or forest/woodland) but were largely independent of climate type (temperate or tropical) and the focus of spatial scale (field or landscape). In conclusion, conservation and restoration of hedgerows contribute to people in several ways by enhancing biodiversity and multifunctionality in agricultural landscapes.

Hedgerows increase the diversity and modify the composition of arbuscular mycorrhizal fungi in Mediterranean agricultural landscapes

“…Hedgerows increased the richness and diversity of AM fungal communities in comparison with crops, supporting our first hypothesis. Hedgerows have been considered an intermediate state between natural woodlands and crops in terms of aboveground biodiversity (Slade et al 2013;García de León et al 2021). Our results suggest that they benefit belowground biodiversity in a similar way.…”

“…The importance of implementing sustainable agricultural practices to address these challenges is highlighted in several EU strategies, such as the Biodiversity Strategy for 2030 and the Farm to Fork Strategy (European Commission 2020). In agricultural landscapes, hedgerows, which are linear structures of woody vegetation that surround agricultural fields (Lajos et al 2020), can contribute to mitigate negative impacts (García de León et al 2021). Hedgerows have been part of the traditional agricultural landscapes to separate different fields in many regions, but their occurrence and extent have significantly diminished because of agricultural intensification in Europe from the 1960s to the 1990s (van den Berge et al 2021).…”

“…Hedgerows have been used to maintain biodiversity and provide ecosystem services in agricultural landscapes (van Vooren et al 2017;García de León et al 2021). Aboveground biodiversity in hedgerows is higher than in cultivated areas, but lower than in natural areas such as forests (Slade et al 2013).…”

Assessing the limiting factors of natural regeneration in Mediterranean planted hedgerows

“…Deciduous Mediterranean woody species usually have higher drought mortality and are more susceptible to herbivory than their evergreen counterparts (Loṕez-Iglesias et al, 2014). The lower performance of deciduous woody plants can be attributed to their higher specific leaf area and growth rate (Paal et al, 2020), which are traits negatively associated with stress resistance (Loṕez-Iglesias et al, 2014;Andivia et al, 2021). However, their higher growth rate can enhance competitiveness when growing with weeds (Suaŕez-Esteban et al, 2013).…”

Hedgerows increase diversity and modifies composition of arbuscular mycorrhizal fungi in Mediterranean agricultural landscapes

“…Hedgerows have been used to restore biodiversity and provide ecosystem services in agricultural landscapes (Van Vooren et al 2017; García de León et al 2021). Aboveground biodiversity in hedgerows is higher than in cultivated areas, but lower than in natural areas like forests (Slade et al 2013).…”