Grazing by semi‐feral cattle and horses supports plant species richness and uniqueness in grasslands

• DOI: 10.1111/avsc.12718
• Publication Date: 2023-02-24T00:14:03Z
• Authors: Christoffer Bonavent; Kent Olsen; Rasmus Ejrnæs; Camilla Fløjgaard; Morten D. D. Hansen; Signe Normand; Jens‐Christian Sv...; Hans Henrik Bruun
• Keywords: Exclosure; Conservation grazing; Quadrat; Graminoid; Standing crop

Abstract Question How does naturalistic grazing (trophic rewilding with large herbivores), in contrast to mowing and free succession (no grazing), affect plant community composition species richness temperate grassland grazed by semi‐feral cattle horses? Location Mols Laboratory, Denmark. Methods We investigated exclosures the area of four years after its establishment. focused on moist dry vegetation, that is, excluding scrub woodland. Each experimental block consisted five 5 × 9 m plots, representing fenced treatments, summer‐only grazing, winter‐only full exclosure annual autumn passive succession. The matrix (the fifth treatment) was herbivores at close‐to‐natural densities, regulated bottom‐up carrying capacity area. Hence, even seasonal treatments were animal density. Quantitative assessed using point‐intercept method 25 cm quadrats, supplemented biomass calibration models based additional which above‐ground harvested recording material sorted weighed. Uniqueness as sum inverse range sizes for constituent (unicity). Results found an appreciably higher than under both exclosure, but only minor differences between treatments. highest year‐round lowest grazing. forb:graminoid ratio tended be high treatment, whereas associated dominance graminoids over forbs. Full‐exclosure plots had accumulation litter richness. Initial heterogeneity within blocks a systematic difference grasslands may have diluted treatment effects this early point onset experiment. Data analysis estimates derived from yielded patterns described above, when compared results obtained raw number intercepts. Conclusions Naturalistic is goal itself ecological restoration, also proposed efficient management tool promote conservation plants communities. prevalence regionally rarer (uni) or abandonment. Similarly, tendency forbs prevail translate into enhanced floral resources anthophilous insects. Summer‐only low density not significantly different much closer natural intensive summer typical agri‐environmental practices.