Insects and Climate Change Flashcards
What is the main cause for global warming
increased concentration of GHG
what are the three trophic levels
Trophic level 1: crops
Trophic level 2: Pests
Trophic level 3: Natural enemies
What variation in temperature for warming could we see over the next century?
1.4 - 5.8 degrees celsius
Are C3 or C4 plants more sensitive to higher CO2 concentrations?
C3 plants are more sensitive (wheat, soybeans, canola)
Do nitrogen-fixing symbionts benefit more from higher CO2 levels
yes
How do increased temperatures affect insects
- increased feeding, development, growth rate and mobility
- influences survival, generation time, population, and geographic ranges
- ## increased overwintering
What is the key driver in insect feeding responses?
C:N ratio in foliage
Describe the positive feedback loop of foliage increased C:N ratios and the insect response
- Altered C:N ratio of the plant = low nutritional quality foliage
- Insects consume increased amounts of foliage to meet their nutritional demands
- Lower foliage quality means slower generation time
- decrease in pest abundance
Although the frequency of precipitation has decreased, the intensity has increased. Why does this make crops more vulnerable to pest infestation?
- expansion of geographic ranges
- increased overwintering survival
- increased number of generations
- reduced biocontrol (natural enemies)
Why are carabid beetles suitable as a biological indicator?
They exhibit quick responses to environmental changes
Are there more or less carabid beetles with climate change
depends on the area, some are seeing a decreased abundance and other areas are seeing an increase
Where do diurnal species decline in population vs where do they thrive?
decline in the continental interior
increase in the north and east
Where are non-fliers noticed to decrease in population?
Dry conditions and areas that are warming
Where were carnivores most likely to decline?
cold and wet climates
