Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 5 pot

... 1–24 25 49 50 –74 75 99 100–149 150 –199 200–400 >400 Recaptured beetles Distance moved (m) 1999 2000 50 5 2 85 156 123 49 4040 54 19 25 14 31 9 24 77 1 4 FIG. 5. 5 Range of dispersal distances ... >2km, and 5% dispersed >5km, whereas 50 % of their primary prey, the southern pine beetle, moved no more than 0.7 km and 95% moved no more than 2. 25 km. St. Pierre and Hendri...

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... DYNAMICS –30 –40 50 –60 –70 –80 01020304 050 051 0 152 0 25 –20 –10 0 10 20 30 40 50 K/T meters Percent of leaves damaged # Damage types 207 404 14 95 252 259 2 05 234 50 0 2 25 209 248 218 436 681 Intermediate and ... example, reduced predator abun- dance usually increases herbivore abundance, thereby decreasing plant abun- dance (Carpenter and Kitchell 1987, 1988, Letourneau and...

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... 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 ... species. V. Anderson and Briske (19 95) simulated 368 12. HERBIVORY 0. 25 0 .50 0. 75 1.00 Maritime I Coastal II Transition III Interior IV 0. 25 0 .50 0. 75 1.00 IIIIII IV Maritime B 0. 25...

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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 ... abundant, whereas predators were more abundant in cleared plots, relative to undisturbed plots.Arthropod abundance was reduced 95. 5% following exper- imental fire, but some organisms survived a...

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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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... 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. I. ... 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...

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... Roughgarden 19 95, Marquis and Whelan 1994, Oksanen 1983). Manipulations in multiple-trophic–level systems have shown that a manipulated increase at one predator trophic level causes reduced abundance of ... exposure to altered temperature and moisture (Seastedt and Cross- ley 1981a).Anthropogenic disturbances leave straighter and more distinct bound- aries between disturbed and undisturbed p...

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... BIOGEOGRAPHY Attack Density 0. 85 0.80 0. 75 0. 65 0. 45 0.70 0.60 0.40 0 .50 0 .55 0. 35 Transect X-Coord (m) 696000 196 850 0 1970000 197 050 0 1971000 197 150 0 1872000 697000 69 650 0 150 0 1 450 1400 Y-C oord (m) Elevation FIG. ... landscape changed from about 75% old- growth to about 75% stands < ;50 years old. A significant proportion of species associated with old-growth for...

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... did not decline over time in ant-removal plots.These results reflected a gradual displacement of small-seeded plants (on which ants specialize) by large- seeded plants (on which rodents specialize) ... 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 turgo...

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