caa a22 4500 467885656 CHVBK 20180406152733.0 cr unu---uuuuu 170328e20060601xx s 000 0 eng 10.1007/s10021-006-0006-4 doi (NATIONALLICENCE)springer-10.1007/s10021-006-0006-4 Alternative Dynamic Regimes and Trophic Control of Plant Succession [Elektronische Daten] [Oswald Schmitz, Elizabeth Kalies, Michael Booth] Ecological succession has been the subject of intense study and debate throughout the history of ecology as conceptualizations of process were proposed and refined. Modern concepts view ecological succession as largely driven by bottom-up resource competition for light and nutrients. However, growing evidence shows that top-down effects of consumers can govern succession. These contrasting perspectives require synthesis. We offer such a synthesis by revitalizing the hypothesis that succession proceeds by abrupt transitions to alternative states or dynamic regimes. We present evidence from field sampling along two successional gradients in a New England old field aimed at identifying pattern, and from experimentation in the same field aimed at identifying process. Field sampling revealed that a competitive dominant plant existed in a mosaic with two distinct patch types of relative abundances (≤ 25% and > 30%). Competitive dominant plant abundance varied systematically with plant species diversity (evenness), and resource supply (light and soil nitrogen). The six-year field experiment tested for alternative regimes by systematic removal and staggered reintroduction of top predators. Long-term predator removal caused an abrupt and irreversible shift from a top-down to a bottom-up controlled regime with a breakpoint at approximately 25% relative abundance of the competitive dominant plant. This caused significant shifts in plant species evenness and resource supply (solar radiation and N mineralization rate). Moreover, the competitive dominant abundance, species evenness and resource supply in the two dynamic regimes matched levels in the different patch types in the field. We conclude that a single ecosystem can display both top-down and bottom-up control. Abrupt shifts in trophic control lead to abrupt changes in the rate of development of ecosystems consistent with a working hypothesis that succession proceeds via abrupt regime shifts. Springer Science+Business Media, Inc., 2006 tropic cascade nationallicence secondary succession nationallicence food webs nationallicence indirect effects nationallicence keystone effects nationallicence alternative states nationallicence Schmitz Oswald School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut Kalies Elizabeth School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut Booth Michael School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut Ecosystems Springer-Verlag; www.springer-ny.com 9/4(2006-06-01), 659-672 1432-9840 9:4<659 2006 9 10021 https://doi.org/10.1007/s10021-006-0006-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10021-006-0006-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Schmitz Oswald School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut NATIONALLICENCE 700 1- Kalies Elizabeth School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut NATIONALLICENCE 700 1- Booth Michael School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, 06511, New Haven, Connecticut, USA aut NATIONALLICENCE 773 0- Ecosystems Springer-Verlag; www.springer-ny.com 9/4(2006-06-01), 659-672 1432-9840 9:4<659 2006 9 10021 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer