Ch 3 Qs

Question 1

Why is there so much biodiversity in the tropics compared to temperate regions? Why are tropical forests so important?

Answer 1

Glaciation limits persistent diversity in northern latitudes
Constant warm temperatures and lack of winters in tropics favors higher productivity, and thus species diversity
Poles and deserts are simply too cold or too dry to support a diversity of life
Shorter generation times due to higher temperatures lead to greater rates of evolutionary change
Tropical forests Sustain over 50% of all species

Question 2

What is an important ecosystem service provided by gases in the stratosphere? How have we / are we affecting this ecosystem service?

Answer 2

Regulation of the earth’s temperature and it’s greenhouse gases (ozone does this)
We are affecting this by burning fossil fuels and creating a hole in the ozone layer

Question 3

What is the difference between good and bad ozone?

Answer 3

Good Ozone: in the stratosphere, protects earth from UV rays

Bad Ozone: ground-level pollutant, harmful to breathe, and damages crops

Question 4

How does soil form? How long does it take?

Answer 4

Soil forms as the weathering of rocks

One inch of topsoil can take hundreds of years

Question 5

How do nutrients become available for uptake by plants? After plants absorb nutrients and incorporate them into their tissues, what eventually happens to those nutrients? How do natural ecosystems differ from human agricultural systems in this respect?

Answer 5

Nutrients become available through decomposition of organic matter in the soil.
Those nutrients are either harvested or eaten by animals

Question 6

Is soil a renewable resource?

Answer 6

Soil renews very slowly, and can become nonrenewable if we deplete it faster than it can be replenished

Question 7

What is the Marcellus Shale, and why is it politically relevant for residents of upstate New York?

Answer 7

A layer of shale, a fine-grained sedimentary rock composed of mud with crystals
It is a popular fracking area with about 500 trillion cubic feet of natural gas lines within the rock

Question 8

How is natural gas extracted from sedimentary rock, such as shale? What are some potential environmental consequences of this type of resource extraction?

Answer 8

Fracking
Polluting of groundwater
Earthquakes
Leakage of Natural Gas and Methane

Question 9

Fundamentally, why do different types of ecosystems (e.g., desert vs. forest) look different from one another?

Answer 9

Climate

-The plants and animals have adapted to the conditions that are present

Question 10

What is the chemical equation for photosynthesis?

Answer 10

6CO2 + 6H2O → C6H12O6 + 6O2

Question 11

How do organisms obtain energy?

Answer 11

They obtain it from the solar energy emitted from the sun or through the means of consumption. Higher level predators have to eat more because 90% of the energy of the food that we consume is lost through natural processes.

Question 12

Are there more trophic levels on land or in the ocean? Why?

Answer 12

More trophic levels in the ocean
In marine ecosystems, microscopic phytoplankton carry out most of the photosynthesis that occurs, while plants do most of this work on land. Phytoplankton are small organisms with extremely simple structures, so most of their primary production is consumed and used for energy by grazing organisms that feed on them

Question 13

What explains differences in GPP as you move geographically west to east across North America?

Answer 13

The Gross Primary Productivity increases as you head towards the west because there is high scale food production that occurs in western states like Iowa and Idaho the US has created the procedure that food primarily grows in the west.

Question 14

Describe the importance of the water cycle for both human and natural systems

Answer 14

Medium for transporting nutrients within and between ecosystems.
Primary sculptor of Earth’s landscape
Natural filtration – evaporation and flowing water

Question 15

How do humans directly or indirectly affect the hydrologic cycle?

Answer 15

We withdraw large quantities of freshwater from rivers, lakes, and aquifers sometimes faster than nature can replace it
We clear vegetation from land for agriculture – increases runoff and reduces rainfall
We drain and fill wetlands for farming and urban development- less flood control

Question 16

How do humans alter the carbon cycle?

Answer 16

Mostly by adding large amounts of carbon dioxide to the atmosphere when we burn carbon-containing fossil fuels
By clearing carbon-absorbing vegetation from forests, especially tropical forests, faster than it can grow back
Greenhouse effect

Question 17

What are the five primary greenhouse gases? What do they do that affects the Earth’s surface temperature?

Answer 17

Water vapor
Carbon dioxide
Methane
Nitrous oxide
Ozone

Question 18

How are microbes involved in the N cycle?

Answer 18

Legumes take in and hold high amounts of carbon

Question 19

How are humans affecting the N cycle?

Answer 19

Large amounts of nitrogen oxides to the atmosphere when we burn gasoline and other fuels and when we use commercial nitrate fertilizers
We add nitrous oxide to the atmosphere through the action of anaerobic bacteria on commercial nitrogen-containing fertilizer or organic animal manure applied to the soil
Removing large amounts of nitrogen from the atmosphere faster than the cycle How are humans affecting the P cycle?
Removal of large amounts of phosphate from the earth to make fertilizer
Clearing tropical forests reduces phosphate levels in tropical soil
Phosphate-rich runoff from the land often produces huge populations of algae

Question 20

How are humans affecting the S cycle?

Answer 20

Weathering away the rock that feeds the soil with nutrients. This would go into the atmosphere and cause acid rain and lower soil fertility

Question 21

What is the biological importance of C, N, P, and S?

Answer 21

C-Photosynthesis,
N- Building Blocks of Amino Acids
P- Components in Nucleic Acids + ATP
S- Present in proteins (amino acids)