Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama 35487-0206, USA.
Section of Integrative Biology, University of Texas at Austin, 1 University Station C0930, Austin, Texas 78712, USA.
Ecology. 2013 Oct;94(10):2220-8. doi: 10.1890/12-2066.1.
Recent interest in the ecological drivers of compensatory and synchronous population dynamics has provided an improved yet incomplete understanding of local and regional population oscillations in response to variable environments. Here, we evaluate the effect of dispersal rate and spatiotemporal heterogeneity in predation by the selective planktivore, bluegill sunfish (Lepomis macrochirus), on local and regional dynamics of zooplankton in pond metacommunities. A metacommunity consisted of three pond mesocosm communities, one with constant presence of predators, one without predators, and one with alternating presence-absence of predators. The three communities were connected at either no, low (0.7% per day), or high (20% per day) planktonic dispersal. Results demonstrate that heterogeneous predation (1) prevents spatial synchrony among prey populations across local communities, (2) disrupts the synchronous population dynamics within communities produced by dispersal, and (3) induces local compensatory dynamics between species within communities regardless of dispersal rate. Taken together, the results emphasize that spatiotemporal heterogeneity in selective predation can inhibit both intraspecific and interspecific synchrony in metacommunities.
最近,人们对补偿性和同步种群动态的生态驱动因素产生了兴趣,这为理解局部和区域种群对变化环境的响应提供了更好但仍不完整的认识。在这里,我们评估了扩散率和选择性滤食性鱼类(蓝鳃太阳鱼)捕食的时空异质性对池塘复合种群中浮游动物的局部和区域动态的影响。复合种群由三个池塘中观社区组成,一个有捕食者存在,一个没有捕食者,一个有捕食者存在和不存在的交替。这三个社区之间的连接是无连接、低连接(每天 0.7%)或高连接(每天 20%)。结果表明,异质捕食:(1)防止了局部社区中猎物种群之间的空间同步性;(2)破坏了扩散产生的社区内同步种群动态;(3)即使在扩散率不同的情况下,也会在社区内的物种之间诱导局部补偿性动态。总之,结果强调了选择性捕食的时空异质性可以抑制复合种群中的种内和种间同步性。