Reconciling the control of the native invasive Jacobaea aquatica and ecosystem multifunctionality in wet grasslands

Grasslands are managed to provide multiple goods and services. During recent decades, abandonment of marginal grasslands and intensification of the most productive sites resulted in biodiversity losses and reduced ecosystem services (ESs). Moreover, invasion by unwanted plants impaired ESs, as seen in Jacobaea aquatica, a poisonous native invader in pre-alpine grasslands of Central Europe. Invasion by this plant compromises fodder quality and endangers animal health, resulting in abandonment of grassland use. We tested different management regimes to reduce J. aquatica in wet grasslands of Southern Germany and assessed how its regulation affects grassland multifunctionality. We monitored indicators associated with productivity and con-servation, such as the abundance of J. aquatica, forage quality, yield, abundance of specialists, and pollinator-relevant plants. Intensive management favoured multifunctionality by promoting productivity and biodiversity, yet also increasing the abun-dance of J. aquatica. Reduced management regulates J. aquatica cover close to an acceptable threshold while also reducing ESs. Thus, we conclude that moderate management strikes a balance between the control of the poisonous plant and the supply of grassland multifunctionality. (c) 2023 The Author(s). Published by Elsevier GmbH on behalf of Gesellschaft fur okologie. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Automated summary

Grasslands are managed to provide multiple goods and services. However, recent decades have seen the abandonment of marginal grasslands and intensification of the most productive sites, leading to biodiversity losses and reduced ecosystem services. Invasion by unwanted plants, such as Jacobaea aquatica, further impairs ecosystem services by compromising fodder quality and endangering animal health. To address this issue, different management regimes were tested in wet grasslands of Southern Germany, and moderate management was found to strike a balance between controlling J. aquatica and maintaining grassland multifunctionality.