Chapter 3

Question 1

Are nutrient circuits involving both
biotic and abiotic components of
ecosystems.

Answer 1

Material or Biogeochemical cycles

Question 2

Elements such as _______, ________, _________, and _________ have gaseous forms, thus, their cycles are global in character and the atmosphere serves as a reservoir.

Answer 2

Carbon, oxygen, sulfur, nitrogen

Question 3

Elements less mobile in the environment like
_________, ___________, _________ and _________ generally cycle on a more localized
scale over the short term. The ______ serves as
the main reservoir for these elements.

Answer 3

Phosphorus, potassium, calcium, trace elements, soil

Question 4

Describes the continuous
movement of water on, above,
and below the surface of the
Earth.

Answer 4

Water Cycle or Hydrologic Cycle

Question 5

_______________ is condensed water
vapor that falls to the Earth’s
surface. Most precipitation
occurs as rain, but also includes
snow, hail, fog drip, graupel, and
sleet.

Answer 5

Precipitation

Question 6

The precipitation that is intercepted
by plant foliage and eventually
evaporates back to the
atmosphere rather than falling
to the ground.

Answer 6

Canopy interception

Question 7

This includes the
variety of ways by which
water moves across the
land.

Answer 7

Runoff

Question 8

The flow of water from the surface into the ground. Once infiltrated,
the water becomes soil moisture or groundwater.

Answer 8

Infiltration

Question 9

Is the flow
of water underground, in the
vadose zone and aquifers.
Subsurface water may return
to the surface (e.g. as a
spring or by being pumped)
or eventually seep into the
oceans.

Answer 9

Subsurface Flow

Question 10

Is the transformation of water
from liquid to gas phases as it moves from the ground or bodies of water
into the overlying atmosphere.

Answer 10

Evaporation

Question 11

Evaporation often implicitly
includes _______________ from
plants, though together they
are specifically referred to as
________________.

Answer 11

Transpiration, Evapotranspiration

Question 12

The state change directly from solid
water (snow or ice) to
water vapor.

Answer 12

Sublimation

Question 13

The movement of
water — in solid, liquid, or
vapor states — through the
atmosphere.

Answer 13

Advection

Question 14

The transformation of water vapor to liquid water droplets in the air,
producing clouds and fog.

Answer 14

Condensation

Question 15

Enumerate the ways by which human activities affect the
water cycle:

Answer 15

1) Withdrawal of large quantities of fresh water from streams, lakes, etc.
2) Clearing of vegetation
3) Reduced infiltration
4) Addition of nutrients

Question 16

It is the cycle of carbon usage by which energy flows through the earth’s ecosystem.

Answer 16

Carbon cycle

Question 17

The life’s chemical backbone.

Answer 17

Carbon

Question 18

The biogeochemical cycle that
describes the transformations of nitrogen
and nitrogen-containing
compounds in nature

Answer 18

Nitrogen Cycle

Question 19

Some symbiotic bacteria (most often associated with leguminous
plants) and some free-living
bacteria are able to fix nitrogen
and assimilate it as organic
nitrogen.

Answer 19

Biological fixation

Question 20

The conversion of ammonia to nitrates is performed primarily by soil-living bacteria and other nitrifying bacteria.

Answer 20

Nitrification

Question 21

Plants can absorb nitrate or
ammonium ions from the soil via
their root hairs.

Answer 21

Assimilation

Question 22

When a plant or animal dies, or an animal
excretes, the initial form of nitrogen is
organic. Bacteria, or in some cases, fungi,
converts the organic nitrogen within the
remains back into ammonia, a process called
______________________.

Answer 22

Ammonification or mineralization

Question 23

The reduction of nitrites back into the largely inert nitrogen gas (N2), completing the nitrogen cycle.

Answer 23

Denitrification

Question 24

Phosphorus circulates through
water, the earth’s crust, and
living organisms

Answer 24

Phosphorous cycle

Question 25

The most common form of phosphorus
used by biological organisms

Answer 25

Phosphate