Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 7 ppsx

... and distur- bance frequency) and insect dispersal ability (Fleishman et al. 2002), and largely 192 7. BIOGEOGRAPHY 0 0 7- P08 877 2.qxd 1/24/06 10:43 AM Page 192 one population successfully crossed ... “natural” ecosystems on all con- tinents. Many herbivorous insects and mites have arrived on agricultural or forestry products and become plant pests in agroecosystems or forests.Some her- b...

Ngày tải lên: 06/07/2014, 14:20

... displacement of small-seeded plants (on which ants specialize) by large- seeded plants (on which rodents specialize) in the absence of rodents. Ant removal led to higher densities of small-seeded species, ... similar to preda- tion and can be described using predation models. However, whereas predation involves multiple prey killed and consumed during a predator’s lifetime, para- sites feed o...

Ngày tải lên: 06/07/2014, 14:20

... 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-P08 877 2.qxd ... However, an ecosystem approach provides a framework for integrating insect ecology with the changing patterns of ecosystem structure and function and for ap...

Ngày tải lên: 06/07/2014, 14:20

... 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 ... aquatic plankton that III. FACTORS AFFECTING DISPERSAL BEHAVIOR 47 002-P08 877 2.qxd 1/24/06 10:33 AM Page 47 red imported fire ants, Solenopsis invicta, are most abundant in disturbed habi- t...

Ngày tải lên: 06/07/2014, 14:20

... reported that pink bollworm, Pectinophora gosypiella, resistance to transgenic (Bt) cotton was associated with reduced per- 76 3. RESOURCE ACQUISITION 003-P08 877 2.qxd 1/24/06 10: 37 AM Page 76 defenses, ... 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 (So...

Ngày tải lên: 06/07/2014, 14:20

... 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 colored to resemble the heads of snakes (Fig. 4.11) (Grant 004-P08 877 2.qxd ... 0. 47 0.42 0.56 0.63 0.53 0.52 Reproduced from Schowalter et al. (1 977 ) with permission from Springer-Verlag. 004-P08 877 2.qxd 1/24/06 10:39 AM Page 97 Wilson 1 975 ). Eusociali...

Ngày tải lên: 06/07/2014, 14:20

... with predators and parasites, but prior to predator satiation (Fig. 5.3) (Southwood 1 975 , 1 977 , see Chapter 8). Mortality resulting from competition and canni- 138 5. POPULATION SYSTEMS 005-P08 877 2.qxd ... 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 repl...

Ngày tải lên: 06/07/2014, 14:20

... 1.00 Stable equilibria 100.0% Invariant loops 27. 0% 5-cycles 23.0% 2-cycles 73 .0% Chaos 83.5% Chaos 39.1% Chaos 1.9% Chaos 0.3% 8-cycles 99.8% 3-cycles 100.0% 3-cycles 45.1% Other cycles 37. 9% 13-cycles 29.9% 19-cycles 7. 1% 6-cycles 54.9% Other cycles 9.3% Other cycles 68.2% FIG. ... exposure to altered temperature and moisture (Seastedt and Cross- ley 1981a).Anthropogenic disturbance...

Ngày tải lên: 06/07/2014, 14:20

... 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 ... woodland maintained by frequent ground fires to closed-canopy II. SUCCESSIONAL CHANGE IN COMMUNITY STRUCTURE 295 010-P08 877 2.qxd 1/24/06 10: 47 AM Page 295 10 Community Dynamics I. Shor...

Ngày tải lên: 06/07/2014, 14:20

... (e.g.,terrestrial organisms captured by aquatic animals, detritus, and dissolved organic material entering 330 11. ECOSYSTEM STRUCTURE AND FUNCTION 011-P08 877 2.qxd 1/24/06 10:48 AM Page 330 Seastedt and Crossley ... aquatic and terrestrial ecosystems. IV SECTION ECOSYSTEM LEVEL 011-P08 877 2.qxd 1/24/06 10:48 AM Page 313 (including detritivores and decomposers) feed on dead plant and an...

Ngày tải lên: 06/07/2014, 14:20