Afforestation and abandonment of semi-natural grasslands lead to biodiversity loss and a decline in ecosystem services and functions

1. During the past century, semi-natural grasslands, once widespread
throughout Europe, have largely been converted into intensively managed
agricultural areas, abandoned or afforested. These large-scale land-use
changes have already resulted in considerable biodiversity loss but can
also lead to a decline in ecosystem service provision and ecosystem
multifunctionality. 2. We assessed the impact of afforestation and
abandonment of semi-natural grasslands on the supply of ecosystem services
in Western Estonia. We compared a wide array of services provided by open
grasslands, abandoned grasslands, and afforested grasslands. Additionally,
we analysed the impact of land-use change and species richness on
ecosystem multifunctionality. 3. Significant declines in the supply of
pollination service, natural pest regulation, forage production, soil
quality, wild food, and cultural appreciation of landscape were detected
as a result of overgrowing or afforestation. 4. There was a significant
positive relationship between species richness and ecosystem
multifunctionality, i.e. more biodiverse grasslands were able to support
more services at a higher capacity. 5. Results show that both grassland
degradation due to abandonment, as well as grassland afforestation, have
significant negative impacts on biodiversity, on the supply of multiple
important ecosystem services and on the ecosystem multifunctionality. 6.
Synthesis and applications. Temperate semi-natural grasslands have high
biodiversity and capacity to deliver multiple important ecosystem services
simultaneously. Conservation and restoration of grassland habitats must be
considered as an important part of sustainable landscape planning.