Midterm Review Q and A

What is the total amount of energy transferred during photosynthesis for a pine forest on a lava flow on Mount Fuji, given NPP is 175,000 kcal/m^2/yr and respiration is 115,000 kcal/m^2/yr?

290,000 kcal/m^2/yr

How do scientists determine the percent change in caribou population from the maximum size of 500,000 to the current size of 198,000?

(198,000 - 500,000)/500,000 * 100

What is the approximate carrying capacity of the seal population based on the graph?

7500

What environmental factor likely caused the change in the harbor seal population size from 1980–1990?

Increased availability of food

What characterizes members of an r-selected species?

They have long life spans.

Which environment is characterized by dry scrub with frequent fires?

B

Which survivorship curve best represents the growth of dandelions, which grow quickly and produce many seeds?

D

What explains the lower humidity found at 30° north and south latitudes?

Warm air rises at the equator, cools, and sinks at 30° latitude.

Based on solar energy received at local noon, what can be concluded about the latitudes of two locations compared in a graph?

Location 1 is close to the equator, and Location 2 is in the Northern Hemisphere.

What is the primary cause of Earth's seasons?

The constant tilt of Earth's rotational axis with respect to the plane of its orbit around the Sun.

What is the ultimate source of energy for terrestrial ecosystems?

The Sun.

How is the spotted lanternfly characterized in the United States?

The spotted lanternfly is a K-selected and invasive species.

What best describes the K-selection reproductive strategy?

Maximizes survival of offspring by producing few offspring with low levels of parental care.

How much energy is available to a tertiary consumer in a lake ecosystem where primary producers store 25,000 kcal/m2/yr?

2550 kcal/m^2/yr.

What is the likely direct effect of a decline in the small fish population on the marine food web?

The jellyfish population will increase because of decreased predation.

Which row indicates the site with the most successful forest reclamation in a table comparing reclaimed coal mining sites?

Row E.

What process is illustrated by a diagram showing changes in an ecosystem over time, starting with bare rock?

Primary succession.

Why does secondary succession occur more quickly than primary succession?

Secondary succession takes place in areas that already have soil and nutrients in place.

When after clear-cutting is species richness greatest in an ecosystem?

100 years.

Where is the greatest remaining natural biodiversity located?

E.

Which biome has the highest net primary productivity due to warm temperatures and abundant sunlight?

Taiga.

How is the biomass of the mice in the pyramid estimated based on thermodynamic laws?

18,705 kg * 0.10 * 0.10.

What measures the biodiversity of an ecosystem?

The total number of different plant species.

How do environmental stressors like wildfires affect biodiversity?

Ecosystems with more species diversity are more likely to recover after a disturbance than those with low diversity.

Which is a cultural ecosystem service provided by forests?

Soil stabilization and air purification.

Which pair of organisms exhibits both competition and predation ecological relationships?

Hawks and Snakes.

Which latitude experiences 24 hours of daylight on December 21?

E.

What describes cycads based on their traits during the Mesozoic era?

K-strategists with a Type III survivorship curve.

What is the best-supported claim about the relationship between tree finches and invasive flies?

The flies and finches have a competitive relationship; finches are more successful at feeding.

How is a symbiotic relationship defined?

Striped bass and bluefish eat the same variety of mackerel.

What will likely happen if total water withdrawal trends continue?

Aquifers will be depleted if demand exceeds recharge rate.

What are two major effects of overgrazing grasslands?

Erosion and desertification.

What pH level predicts 50% survival for water fleas after 2 hours exposure?

4.5.

What type of irrigation is used in orchards and can increase soil erosion?

Furrow irrigation.

What is a disadvantage of genetically modifying crops?

It can decrease the genetic diversity of crop species.

What is an unintended consequence of pesticide use in agriculture?

Organisms build resistance through genetic mutation requiring stronger pesticides.

What is a benefit of concentrated animal feeding operations?

They are efficient, low-cost facilities that keep consumer costs low.

What most likely increases nutrient levels and bacteria content in lake water?

Runoff from a nearby hog farm.

What does an integrated pest-management approach emphasize?

Reduction of crop damage to an economically tolerable level.

What practice minimizes soil erosion?

No-till agriculture.

Which practice aligns with producing organic crops per USDA guidelines?

Using pheromones to disrupt insect mating cycles.

Which soil horizon, developed in areas with dense vegetation, consists of decomposing material?

A.

Which agricultural practice likely improves water quality in nearby streams and rivers?

Using crop rotation in fields.

What is the order of soil particles from smallest to largest?

Clay—silt—sand.

What describes soil with 25% clay, 25% silt, and 50% sand?

Sandy Clay Loam.

How does burning fossil fuels affect atmospheric carbon levels?

Carbon sequestered underground is added to the carbon cycle.

What are the two major processes involved in the carbon cycle?

Photosynthesis and respiration.

What conclusion can be made when invasive plants live in nutrient-poor soil and nitrogen compounds are found later?

Bacteria convert free nitrogen into nitrogen compounds.

What is Nitrification?

Ammonia is converted to nitrite, then to nitrate.

What prevents sediment runoff into streams in a watershed with road work and dairy farms?

Maintain zones of grass at least 100m wide on the sides of streams.

Why did dissolved oxygen levels decrease as waste increased after one week?

Algae multiplied, then died and decomposed.

What is a consequence of lack of genetic diversity in food crops like corn?

Increased susceptibility to plant diseases.

What describes bioaccumulation?

Absorption of a substance by an organism at a rate greater than elimination.

What risk is associated with using biological controls instead of chemical pesticides?

The control agent may harm beneficial species as well.

How do synthetic chemicals like PCBs affect ecosystems?

They act as estrogen mimics, impacting secondary consumers.

How are Farm A and Farm B described in a comparison of farming types?

Farm A is grass-fed pasture; Farm B is a traditional concentrated animal feedlot.

What type of irrigation is labor-intensive and requires extensive setup?

Drip irrigation.

What effect do dioxins have on alligators in a polluted Florida lake?

Acting as endocrine disruptors.

Why is vegetarianism cited as a solution to deforestation?

More people can be fed using less agricultural land.

What is the negative impact of using Lindane for pest control?

It has a negative and persistent impact on the ecosystem.