land transformation global change

Question 1

what are three common changes to natural systems for agriculture?

Answer 1

• deforestation
• draining or modification of wetlands
• modification of grasslands

Question 2

at what stage does a tree sequester more carbon?

Answer 2

when it is growing the most -> young trees

Question 3

what are the outcomes of deforestation and transformation to agricultural land on carbon sequestration?

Answer 3

• uptake of carbon reduced (crops do not take up same amount of C and pastures emit GHG through respiration)
• carbon stored in wood is returned through atmosphere through decomposition

Question 4

what are the effects of deforestation on the hydrological cycle?

Answer 4

• a large tree population can impact local weather patterns through the high degree of transpiration and the cloud-seeding secondary chemicals (more cloud cover)
• more loss of water from runoff or soil infiltration

Question 5

what is a flying river?

Answer 5

a system that brings moisture over large areas as a result of wind currents and significant plant transpiration

Question 6

what is slash-and-burn agriculture?

Answer 6

farming technique that involves the removal of woodland through the use of farming that leads to nutrient rich ash in the soil

Question 7

what are the consequences of slash-and-burn agriculture?

Answer 7

the soil will be depleted of nutrients quickly because rain will cause nutrients to be lost in soil so more forest needs to be burned (positive feedback)

Question 8

what biome has the most reliable form of carbon sequestration?

Answer 8

grasslands because it stores carbon in soils instead of above ground biomass so when there is an increase in frequency of forest fires, roots and soils will survive and continue to store that carbon

Question 9

what are the impacts of wetland conversion?

Answer 9

• conversion of green and blue reservoir to system that holds much less water for a shorter period of time
• change in GHG cycles (fertilizer, cow methane, intense agriculture)
• soil degradation (loss of organic matter)
• loss in biodiversity
• loss of ecosystem services such as water filtration and flood prevention

Question 10

what is the urban heat island?

Answer 10

increased temperature resulting from heat radiation from low albedo man made structures