Chapter 042 Complete Solution 2023 Verified 100%
A 3-hectare lake in the American Midwest suddenly has succumbed an algal bloom. What is the likely
cause of eutrophication in freshwater ecosystems, such as this one? correct answers Nutritional runoff
A cow's herbivorous diet indicates that it is a(n) correct answers Primary consumer
Approximately how many kg of carnivore biomass can be supported by a field plot containing 1,000 kg
of plant material? correct answers 10
Aquatic ecosystems are most likely to be limited by which of the following nutrients? correct answers
Carbon
Aquatic primary productivity is most limited by which of the following? correct answers Light & nutrients
Consider the food chain grass -> grasshopper -> mouse -> snake -> hawk. How much of the chemical
energy fixed by photosynthesis of the grass (100%) is available to the hawk? correct answers 0.01%
Corn production in many states of the Midwest is limited by nitrogen levels in the soil. Some farmers
reduce the need to apply expensive anhydrous ammonia to their fields by rotating corn crops with
nitrogen-fixing soybean crops. Using soybeans to add nitrogen to soils is an example of correct answers
Biological augmentation
For most terrestrial ecosystems, pyramids composed of species abundances, biomass, and energy are
similar in that they have a broad base and a narrow top. The primary reason for this pattern is that
correct answers At each step, energy is lost from the system as a result of keeping the organisms alive
How do the Taylor Glacier bacteria produce their energy? correct answers Chemoautorophism
How does inefficient transfer of energy among trophic levels result in the typically high endangerment
status of many top-level predators? correct answers Top-level predators are destined to have small
populations that are sparesly distributed
How does phosphorus normally enter ecosystems? correct answers Rock weathering
How is it that satellites can detect differences in primary productivity on Earth? correct answers
Satellites detect differences by comparing the wavelengths of light captured & reflected by
photoautotrophs to the amount of light reaching
How is it that the open ocean produces the highest net primary productivity of Earth's ecosystems, yet
net primary productivity per square meter is relatively low? correct answers Oceans have the largest
area of all the ecosystems on Earth