Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 12 pot

... are affected significantly by above-ground, as well as below-ground, herbivory. Morón-Ríos et al. (1997a) noted that root-feeders reduced root-to-shoot ratios by 40% and live-to-dead above-ground ... replacement by plant species with lower N concentrations, in an oak savanna in the north central United States. Reduced metabolic demands by pruned or defoliated plants can reduce water and nutr...

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... Following the appearance of transgenic insect- resistant crop species in the late 1980s, geneti- cally engineered, Bt toxin-producing corn, cotton, soybeans, and potatoes have replaced nontransgenic varieties ... labora- tory experiment with sex-linked mutant genes in Drosophila melanogaster (Peterson and Merrell 1983), mutant and wild-male phenotypes exhibited about the same viability, but...

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... particular tolerances to disturbance or postdistur- bance conditions (see Chapter 2). Often, legacies from the predisturbance com- munity (such as buried rhizomes, seed banks, woody litter, and animals ... converged toward significantly greater similarity in structure following fire in a grassland ecosystem than pre- dicted by a random model. Fukami et al. (2001) modeled compartmentalized c...

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... hierarchical approach offers a means of integrating evolutionary and ecosystem approaches to studying insect ecology. The evolutionary approach IV. ECOSYSTEM APPROACH TO INSECT ECOLOGY 11 001-P088772.qxd ... However, an ecosystem approach provides a framework for integrating insect ecology with the changing patterns of ecosystem structure and function and for appl...

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... environmental changes, as described earlier, any change will alter insect abundance and distribution and may increase the incidence of crop pests and vectors of human and animal dis- eases (Stapp ... forest canopy and are carried by wind currents to new areas (Wellington 1980). The distance traveled by wind- or water-dispersed insects depends on several factors, including flow rate and inse...

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... limited number of resistance mechanisms that confer cross-resistance to plant defenses and structurally related toxicants and, in some cases, to chemi- cally unrelated compounds (Soderlund and ... parasites and pathogens in the hemo- coel (Tanada and Kaya 1993). Behavioral mechanisms also may be used for pro- tection against pathogens. Insects produce a variety of antibiotic and anticancer .....

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... eyespots of moths usually are hidden on the hind wings during rest and can be exposed sud- denly to startle would-be predators. The margin of the front wings in some sat- urniids are shaped and ... allocated as is K), and 85 Sr (assimilated and allocated as is Ca), became use- ful tools for tracking the assimilation and allocation of nutrients through organ- isms, food webs, and ecosystems....

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... exposure to altered temperature and moisture (Seastedt and Cross- ley 1981a).Anthropogenic disturbances leave straighter and more distinct bound- aries between disturbed and undisturbed patches (because ... growing population, and preda- tors and pathogens respond to increased prey or host density and stress. Popu- lation growth slows and abundance reaches a peak. Competition, predation, and...

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... (Fig.7.9).Mound den- sities were significantly highest along dirt roads not covered by forest canopy and lowest along roads covered by forest canopy. Powerline and graveled or paved roads not covered by forest ... length. These modifica- tions eliminate habitats in overflow areas (such as wetlands and side channels) and in logs and other impediments and accelerate drainage in the channeled sec-...

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... 1994, see Chapter 13). Insects are an important food source for a variety of other organisms. Car- nivorous plants generally are associated with nitrogen-poor habitats and depend on insects for ... 1989, Krafft and Handel 1991). A variety of mechanisms for entrapment of insects has evolved among carnivorous plants, including water-filled pitchers (pitcher plants), triggered changes in turg...

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