Herbivore exclusion promotes a more stochastic plant community assembly in a natural grassland

0507408 - BÚ 2020 RIV US eng J - Článek v odborném periodiku
Alberti, J. - Bakker, E.S. - van Klink, Roel - Olff, H. - Smit, C.
Herbivore exclusion promotes a more stochastic plant community assembly in a natural grassland.
Ecology. Roč. 98, č. 4 (2017), s. 961-970. ISSN 0012-9658. E-ISSN 1939-9170
Institucionální podpora: RVO:67985939
Klíčová slova: bottom-up effects * determinants of plant community diversity and structure * different-sized herbivores * null model * random and deterministic processes * top-down effects
Obor OECD: Ecology
Impakt faktor: 4.617, rok: 2017
Způsob publikování: Omezený přístup

Both bottom-up (e.g., nutrients) and top-down (e.g., herbivory) forces structure plant communities, but it remains unclear how they affect the relative importance of stochastic and deterministic processes in plant community assembly. Moreover, different-sized herbivores have been shown to have contrasting effects on community structure and function, but their effects on the processes governing community assembly (i.e., how they generate the impacts on structure) remain largely unknown. We evaluated the influence of bottom-up and top-down forces on the relative importance of deterministic and stochastic processes during plant community assembly. We used the data of a 7-yr factorial experiment manipulating-nutrient availability (ambient and increased) and the presence of vertebrate herbivores (> 1 kg) of different body size in a floodplain grassland in The Netherlands. We used a null model that describes a community composition expected by chance (i. e., stochastic assembly) and compared the plant community composition in the different treatments with this null model (the larger the difference, the more deterministically assembled). Our results showed that herbivore exclusion promoted a more stochastic plant community assembly, whereas increased nutrients played a relatively minor role in determining the relative importance of stochasticity in community assembly. Large herbivores facilitated intermediate-sized mammal herbivores, resulting in synergistic effects of enhanced grazing pressure and a more deterministic and convergent plant community assembly. We conclude that herbivores can act as strong deterministic forces during community assembly in natural systems. Our results also reveal that although large-and intermediate-sized mammal herbivores often have contrasting effects on many community and ecosystem properties, they can also synergistically homogenize plant communities.
Trvalý link: http://hdl.handle.net/11104/0298969