Movement of Elements

Question 1

Nutrients

Answer 1

Elements required by organisms for metabolism and growth

Question 2

Biogeochemistry

Answer 2

Physical, chemical, biological factors that influence the movements and transformation of elements

Question 3

Elements … among biotic and abiotic ecosystem components

Answer 3

cycle

Question 4

Assimilation

Answer 4

requires energy. Inorganic to organic.

Question 5

Dissimilation

Answer 5

releases energy. Organic to inorganic.

Question 6

Two abiotic sources of nutrients

Answer 6

Minerals and gases

Question 7

Mechanical Weathering

Answer 7

Physical alteration of rocks. Freezing, wetting/rewetting, otherwise “broken apart”

Question 8

Chemical Weathering

Answer 8

Minerals subjected to chemical processes. Lichens do both this and mechanical weathering.

Question 9

Atmospheric Deposition

Answer 9

Precipitation, particles, aerosols, and gases move from the atmosphere to the earths surface

Question 10

Hydrologic Cycle

Answer 10

The movement of water through ecosystems and atmosphere; driven by evaporation, transpiration, and precipitation

Question 11

Detritovores

Answer 11

Physically break organic matter into smaller pieces.

Question 12

Decomposers

Answer 12

Break dead organic matter into inorganic elements. Process called mineralization.

Question 13

The true decomposers are the … who …

Answer 13

bacteria and fungi, convert organic macromolecules into soluble nutrients

Question 14

Decomposition proceeds most rapidly at

Answer 14

warm temperatures

Question 15

Low soil moisture leads to

Answer 15

decreased decomposition.

Question 16

High soil moisture leads to

Answer 16

low oxygen concentrations which lowers the activity of decomposers.

Question 17

Moist forests have … rate of decomposition

Answer 17

low, not water logged

Question 18

High quality detritus has lower … ratios because … is important for decomposition

Answer 18

C:N, nitrogen

Question 19

Less nitrogen means

Answer 19

slower decomposition

Question 20

Atmosphere is made of mostly

Answer 20

nitrogen

Question 21

Nitrogen is required by … organisms

Answer 21

all

Question 22

Too much nitrogen can cause

Answer 22

toxic plant/algae growth. The amount of fixed nitrogen is increasing.

Question 23

Nitrogen fixation

Answer 23

The entrance. Converts atmospheric nitrogen into forms consumers can use. Nitrogen to ammonia to ammonium or nitrate

Question 24

Biotic fixation

Answer 24

A type of nitrogen fixation involving free-living and mutualistic bacteria

Question 25

Abiotic fixation

Answer 25

A type of nitrogen fixation involving lightning, wildfires, fossil fuel combustion, fertilizer production.

Question 26

Intermediate Nitrogen Processes

Answer 26

Nitrification, assimilation, ammonification

Question 27

Nitrification

Answer 27

Conversion of ammonium to nitrate by bacteria. Nitrates more easily used by plants

Question 28

Assimilation of nitrogen

Answer 28

Incorporation of NH4+ or NO3- into organism tissues

Question 29

Ammonification

Answer 29

Nitrogen in organic matter (feces, dead organisms) converted to ammonia or ammonium. Fungal and bacterial decomposers. Can then be converted back into nitrates.

Question 30

Denitrification

Answer 30

The exit. Nitrates are water soluble and are leached from the surface. Nitrates are converted back intro nitrogen gas (N2) by bacteria under anaerobic conditions. NO3 to NO and NO to N2.

Question 31

Like nitrogen, ... is an essential element

Answer 31

phosphorus

Question 32

Phosphorus moves as ...

Answer 32

Phosphate (PO43-). Often limits productivity. Excessive phosphorus can cause toxic plant/algae growth.

Question 33

Phosphorus only enters the atmosphere as ...

Answer 33

dust

Question 34

Plants assimilate phosphate which then moves to the ... and when they die their excretion and decomposition allows it to ...

Answer 34

consumers, go back into the soil for future leaching or going into runoff.

Question 35

Some sedimentary rock from phosphorus is ... allowing the phosphorus back into ...

Answer 35

uplifted from aquatic systems, terrestrial systems.

Question 36

Three major processes by humans that have increased N-fixation

Answer 36

Haber bosch, crops, gaseous emissions

Question 37

Oligotrophic

Answer 37

Low nutrient levels. Low NPP. Healthy, diverse fish and invertebrate communities

Question 38

Eutrophic

Answer 38

Nutrient rich. High phytoplankton, algae abundance and turnover. Oxygen depleted leads to anaerobic organisms. Accumulation of detritus leads to turbid and cloudy water. Loss of diversity.

Question 39

Consequences of eutrophication

Answer 39

Hypoxia creates dead zones. Inability for fish to get oxygen.