From Individuals to Ecosystems 4th Edition - Chapter 17 ppsx

... water too deep for photosynthesis to be appreciable or even to take place at all, but it derives its energy base from dead phytoplankton, bacteria, animals and feces that sink from the autotrophic ... productivity EIPC17 10/24/05 2:12 PM Page 516 522 CHAPTER 17 in a variety of terrestrial and aquatic ecosystems. Figure 17. 26b re-emphasizes how consumption efficiency by grazers i...

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... post-emergence activity. The phenol derivatives, particularly the nitrophenols such as 2-methyl-4,6-dinitrophenol, are contact chemicals with broad- spectrum toxicity extending beyond plants to ... We cannot con- tinue to use the same pesticides if increasing numbers of pests become resistant to them. We cannot (if we wish to have fish to eat in future) continue to remove fish fr...

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... species richness from island to island was partitioned, statistically, into that attributable to island area alone, that attrib- utable to habitat diversity alone, that attributable to correlated variation ... species richness may be related to an increase in pro- ductivity as one moves from the poles to the equator. The length of the growing season increases from the poles...

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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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... 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 175 0 to about 370 µll −1 today and is still ... Patterns of prim- ary productivity are examined in Chapter 17. Relatively little space in this chapter is given to food as a resource for animals, simply because a series of...

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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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... (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 ... attracting individuals to disperse towards one another and forces provoking individuals to disperse away from one another. As we shall see in a later chapter, such compromi...

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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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