Characterizing relationships between individual body size and trophic niche position is essential for understanding how population and food-web dynamics are mediated by size-dependent trophic interactions. However, whether (and how) intraspecific size-trophic relationships (i.e., trophic ontogeny pattern at the population level) vary with time remains poorly understood. Using archival specimens...

The article evaluates the ecological status of five small lakes on Valaam Island (Igumenskoe, Chernoe, Ossievo, Nikonovskoe, Krestovoe) using macrophytes as bioindicators. methods proposed by Finland, Sweden, and Norway were used, to assess state eutrophication, change in composition specific species, water level, acidification, according different indexes (Reference index (RI), Trophic Macroph...

It has been well established that the trophocytes, or nurse cells of heteropterous ovaries, contribute a variety of cytoplasmic components to the developing oocytes (Bonhag, 1958) . Hemipteran ovaries are of the telotrophic type in which the nurse cells are confined to the apical trophic-chamber of each ovariole and are connected to developing oocytes, during their early stages of differentiati...

Consumer trophic position 2 3 4 5 Im pa ct s on p rim ar y pr od uc tiv ity (p ro po rti on al c ha ng e) -0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 40% consumption of lower trophic level a r t i c l e i n f o

IntraspeciWc diversity can inXuence the structure of associated communities, though whether litter-based and foliage-based arthropod communities respond to intraspeciWc diversity in similar ways remains unclear. In this study, we compared the eVects of host-plant genotype and genotypic diversity of the perennial plant, Solidago altissima, on the arthropod community associated with living plant ...

These impacts of fisheries have led, in the late 1990s, to a growing interest in "ecosystembased management" (see e.g. NRC, 1999). Moreover, though the full implications of such form of management continue to remain elusive, there is a growing understanding that ecosystembased management must consider and maintain the structuring role of large predators in marine food webs. The demonstration by...

Productivity, trophic structure, and energy flow in the steady-state ecosystems of Silver Springs, Florida W.M. Kemp a,∗, W.R. Boynton b a Horn Point Laboratory, Center for Environmental Science, University of Maryland System, Box 775, Cambridge, MD 21613, USA b Chesapeake Biological Laboratory, Center for Environmental Science, University of Maryland System, 1 Williams Street, Solomons, MD 206...

We tested whether standing autotrophic (unicellular algal) biomass is sensitive to variation in initial consumer (nondecomposer, heterotrophic protistan) diversity in experimental microbial microcosms. Our results showed a strong, negative relationship between autotrophic biomass and consumer species richness. Additional microcosm experiments showed that this relationship was due largely to the...