Genetic Variation of Typical Plant Species in Hay Meadows: The Effect of Land Use History, Landscape Structure, and Habitat Quality

Abstract

Global changes in land use are threatening the diversity of many ecosystems on both the intra- and interspecific levels. Among these ecosystems are the species-rich hay meadows, which have drastically declined in quality and quantity, due to land use intensification or abandonment in recent decades. The remaining genetic resources of their plant species must therefore be protected. To determine the driving forces impacting genetic variation in common hay meadow species (Dactylis glomerata, Heracleum sphondylium, and Trifolium pratense), we used data on the land use history, historic and present landscape structure and habitat quality. Our results showed average genetic diversity within the study sites, with low differentiation levels and a high gene flow among grasslands. Land use history, landscape structure and habitat quality were found to be related to the distribution of genetic diversity in the studied species, highlighting the complex forces acting in these ecosystems and showing the specific impact of litter accumulation on genetic diversity. Both historic and current environmental variables influence genetic diversity, demonstrating the importance of the land use history of a habitat. The most important group of variables impacting genetic variation in all three species was the landscape structure (e.g., distance to the nearest-located urban area or grassland). Also important was the influence of litter cover on genetic diversity in D. glomerata, which provides an interesting starting point for further research.

The impact of environment on genetic and epigenetic variation inTrifolium pratensepopulations from two contrasting semi-natural grasslands

“…Previous studies about genetic diversity patterns in common CG [ 64 ] and OM plant species [ 65 ] observed a trend to higher genetic diversity levels in CG populations. Within the study region, CGs are still managed by migratory sheep herding and are, thus, exposed to elevated levels of disturbance by grazing and trampling.…”

“…Pagel et al . [ 65 ] postulated landscape structure as a key variable for genetic diversity of T. pratense populations in OMs, while they could not observe any impact of local habitat quality. Therefore, genetic diversity of T. pratense may be affected more by landscape structure, related management, and/or gene flow patterns than by local environmental conditions.…”

Eco-evolutionary dynamics in grasslands during land use change: consequences for plant-microbe interactions and ecosystem function

“…Similarly, abandonment reduces the local population sizes of grassland specialists as they are replaced by encroaching species (Bakker et al, 1980;Lindborg et al, 2005;Johansson et al, 2008;Lehtilä et al, 2016), resulting in genetic bottlenecks and increasing the effect of genetic drift (Busch & Reisch, 2016;Lehmair et al, 2020). In regions where grassland management has been abandoned at a landscape scale, loss of connectivity impedes gene flow between populations, further reducing within-population genetic diversity (Prentice et al, 2006;Helm et al, 2009;Aavik et al, 2019;Lehmair et al, 2020;Pagel et al, 2020;Reinula et al, 2021).…”

Limited effects of population age on the genetic structure of spatially isolated forest herb populations in temperate Europe

“…Theoretically, old populations in remnants of once large, contiguous forests experienced steady gene flow and/or benefited from a frequent introduction of new genotypes before fragmentation (Pagel et al., 2020 ). They also had more time for genetic mutations to accumulate (Willi et al., 2018 ).…”