Natural Cycles and Human Impacts on the Environment

Question 1

Sustainable landscapes strive to mimic and minimally impact ______ ______ within the built environment.

Answer 1

natural cycles

Question 2

The hydrologic cycle is the continuous movement of _____ above, on, and below the surface of the earth in either a solid, liquid, or gaseous state.

Answer 2

water

Question 3

Describe the rain (precipitation) cycle.

Answer 3

Precipitation infiltrates the soil, evaporates into the atmosphere, or runs off the Earth’s surface to a stream, wetland lake, or ocean.

Question 4

In a natural setting free from human impacts, precipitation provides a means to regular water quality and quantity through _______ and _____.

Answer 4

infiltration and filtration

Question 5

Name three ways the built environment has an effect on the distribution, quantity, and quality of water in the hydrologic cycle.

Answer 5

agriculture, urban and industrial development, and water withdrawals for human use

Question 6

When precipitation cannot be infiltrated into the ground due to impervious surfaces, we call this _______.

Answer 6

stormwater runoff

Question 7

Stormwater runoff is typically directed to storm sewers (or storm drains) and drain to what two areas?

Answer 7

stormwater management facilities or directly into streams

Question 8

Stormwater that’s directed into streams can scour streambanks and increase the sediment loading (muddy appearance) of the stream. What impact does sediment loading have on the habitat?

Answer 8

Sediment loading causes poor water quality and can kill aquatic life

Question 9

The carbon cycle has geological, chemical, and biological components. It can be divided into these 5 major components:

Answer 9

1. the atmosphere
2. living plant and animals
3. oceans (dissolved inorganic carbon and living and non-living marine life)
4. sediments (fossil fuels, freshwater systems, non-living organic material)
5. Interior of the earth (mantle and crust)

Question 10

Plants play a key role in the movement of carbon. How do plants move carbon through their system?

Answer 10

Photosynthesis (CO2 in the atmosphere, water, and light are absorbed to produce O2 and food (carbohydrates) for growth. Once plants die, their carbon is recycled back into the atmosphere through decomposition.

Question 11

Carbon in the Earth’s atmosphere primarily exists as ______ and _____.

Answer 11

carbon dioxide and methane

Question 12

What is the greenhouse effect?

Answer 12

Human activities that have increased the amount of carbon in the atmosphere. Carbon dioxide, methane, and other greenhouse gasses trap thermal radiation like a blanket. These gases would otherwise radiate away into space, but instead cause an increase in temperature.

Question 13

What plant is one of the most efficient processors of carbon?

Answer 13

Trees - they uptake carbon (through photosynthesis) and convert it to wood as they grow (sequestration). When they die it is slowly released back into the atmosphere and soil through decay or burning.