Effects of functionally diverse seed mixtures on dry matter yield and forage quality of a central European grassland

Abstract

The debate on balancing agricultural production and biodiversity conservation has intensified in response to increasing global livestock production and more intensive grassland use. This is because productive grasslands show high yield but low species diversity. Increasing the forage quality by improving low-diversity grasslands may be an option to combine agricultural needs with biodiversity promotion. Reseeding species-poor swards with legumes and non-legume forbs has become feasible with the increasing commercial availability of native seeds. Thus, functionally diverse mixtures should be developed and tested, since there is little knowledge on the establishment of such species and their effects on yield and forage quality. Therefore, we designed four legume and forb-rich seed mixtures (‘toppings’) and tested them in combination with two standard grass-based agricultural mixtures (‘grass mixtures’) during a four-year mesocosm experiment that simulated agricultural management through cutting and fertilizing. Plant establishment, dry matter yield, metabolizable energy (ME) as a measure of forage quality, and functional diversity (richness, divergence, evenness) were recorded every year. We further asked whether season (spring, summer, autumn) moderates the effects of community composition and functional structure on dry matter yield and forage quality. The experiment showed that season was the dominant source of variation in both dry matter yield and ME. Dry matter yield decreased with increasing cover of legumes and forbs, while harvest season was the dominant driver of productivity, with the highest yields in spring and the lowest in autumn. Metabolizable energy of pooled samples for each topping × grass-mix combination tended to increase with legume-forb cover, whereas the effects of functional diversity were inconsistent and depended on mixture composition and harvest season. Nine of 13 introduced species established, with Trifolium pratense , Galium album , Lotus corniculatus , and Plantago lanceolata being most abundant, identifying them as candidates for further field evaluation rather than immediate large-scale recommendation.

The authors' abstract, as published at the source. Frontiers in Sustainable Food Systems, 2026 · DOI ↗