From Individuals to Ecosystems 4th Edition - Chapter 16 pot

... experimental grassland subjected to continuous fertilizer from 1856 to 1949. ((a–c) after Tokeshi, 1993.) EIPC16 10/24/05 2:10 PM Page 473 •• •• 494 CHAPTER 16 Density (individuals cm –2 ) Chthamalus ... (Section 16. 3), in time (Sections 16. 4 16. 6) and finally in a combined spatiotemporal setting (Section 16. 7). 16. 2 Description of community composition One way to charac...

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... leav- ing the remainder with the potential to regenerate. Grazers feed on (or from) many prey during their lifetime. True predation and grazing are discussed in detail in Chapter 9. Parasitism, too, ... dioxide The CO 2 used in photosynthesis is obtained almost entirely from the atmo- sphere, where its concentration has risen from approximately 280 µll −1 in 1750 to about 370 µll...

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... (Murton et al., 1966). Individuals may also gain from living in groups if this helps to locate food, give warning of predators or if it pays for individuals to join forces in fighting off a predator ... areas; horizontally striped spots indicate the stop-over areas, used only during south- and northward migration; the cross-hatched spots indicate the areas used both as stop-over and...

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... times take longer to respond to increases in prey abundance, and longer to recover when reduced to low densities. The same phenomenon occurs in desert communities, where year -to- year variations ... seeds, mealworms, zooplankton relative to fish), it often fails to pre- dict diets of foragers that attack mobile prey (small mammals, fish, zooplankton relative to insect predators)...

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... it from the anemone’s sting- ing nematocysts (the normal function of the anemone slime is to prevent discharge of nematocysts when neighboring tentacles touch). The fish derives protection from ... be toxic to the host. 13.5.2 Ruminant guts The stomach of ruminants comprises a three-part forestomach (rumen, reticulum and omasum) followed by an enzyme- secreting abomasum that is similar...

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... area showing the gradual change from pasture to cliff conditions. (c) The mean length of stolons produced in the experimental garden from samples taken from the transect. (From Aston & Bradshaw, 1966.) the ... evolutionary history. All species are absent from almost everywhere, and we consider next, in Chapter 2, the ways in which environmental conditions vary from place...

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... sampled from diverse localities in northern USA and Canada, and were tested for freezing tolerance and ability to acclimate to cold. Individuals from the most freeze-tolerant population (from ... environ- mental conditions because water tends to move into organisms from the environment and this needs to be resisted. In marine habitats, the majority of organisms are isotonic...

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... sometimes to pupae, and then to adults; plants pass from seeds to seedlings to photosynthesizing adults; and so on. The different stages are likely to be influenced by different factors and to have ... population to describe a group of individuals of one species under investigation. What actually constitutes a popula- tion, though, will vary from species to species and f...

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... therefore trajectories that follow a cohort through time. This is indicated by arrows, pointing from many small, young individuals (bottom right) to fewer, larger, older individuals (top left). Mean ... small population sizes: A to B, B to C) and is small close to the carrying capacity (I to J, J to K), but is large at intermediate densities (E to F). The result is an ‘S...

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... which grows from 1900 to 3000 m. But as colder weather sets in, they travel to lower elevations and from October to May they feed primarily on Bashania fargesii, which grows from 1000 to 2100 m. ... in twelve 5-year age classes through dis- crete 5-year time steps. Values for age-specific survivorship and density-dependent reproductive rates were derived from a thorough data...

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