Trophic interactions across lake–stream boundaries in mountain lakes

Trophic Cascades in Lakes:

Food Web Topology in High Mountain Lakes

Although diversity and limnology of alpine lake systems are well studied, their food web structure and properties have rarely been addressed. Here, the topological food webs of three high mountain lakes in Central Spain were examined. We first addressed the pelagic networks of the lakes, and then we explored how food web topology changed when benthic biota was included to establish complete tro...

Oligocene stratigraphy across the Eocene and Miocene boundaries in the Valley of Lakes (Mongolia)

Cenozoic sediments of the Taatsiin Gol and TaatsiinTsagaan Nuur area are rich in fossils that provide unique evidence of mammal evolution in Mongolia. The strata are intercalated with basalt flows. 40Ar/39Ar data of the basalts frame the time of sediment deposition and mammal evolution and enable a composite age chronology for the studied area. We investigated 20 geological sections and 6 fossi...

Piscivore addition causes a trophic cascade within and across ecosystem boundaries

Th e addition of predators can play a key role in structuring ecological communities through both consumptive and nonconsumptive eff ects. Stocking of piscivorous fi sh in lakes and similar experimental introductions have provided fundamental evidence in support of trophic cascade theory. Yet, the impact of piscivore addition on cross ecosystem subsidies and meso-predator resource use has not b...

Urea and ureolytic activity in lakes of different trophic status.

Urea and uraease (U-ase) activity were determined in water samples taken from the surface layers of 17 lakes of different trophic status. Urea concentrations were inversely correlated with the trophic status of the studied lakes and varied from below the detection limit to 25 micromol l(-1). Maximal potential ureolytic activity (V(max)) ranged from 0.2 to 7.0 micromol l(-1) h(-1). The highest u...