Soil food web

Question 1

What is the soil food web?

Answer 1

Soil food web is the community of organisms living all or part of their lives in the soil. It describes the transfer of energy and nutrients between species in soil ecosystem.

Question 2

What are photoautotrophs?

Answer 2

Get their energy from light and carbon source from CO2.

Question 3

What are photoheterotrophs?

Answer 3

Get their energy from light and carbon source from organic compounds.

Question 4

What are chemoautotrophs?

Answer 4

Get their energy from inorganic chemical reactions and carbon sources from CO2

Question 5

What are chemoheterotrophs?

Answer 5

Get their energy from inorganic chemical reactions and carbon source from organic compounds.

Question 6

What are examples of photoautotrophs?

Answer 6

Chorella species (Green algea)
Nostoc species (Star Jelly)
Plants

Question 7

What are examples of chemoautotrophs?

Answer 7

1. Ammonia oxidizer: Nitrosomonas species
2. Sulfur oxidizer: Thiobacillus denitrificants

Question 8

What is an example of photoheterotroph?

Answer 8

Purple non-sulfur bacteria.

Question 9

What is an example of Chemoheterotrophs?

Answer 9

Most animals

Question 10

What are the 4 structural characteristics of the soil food web?

Answer 10

1. Organic material fuels the soil food web.
2. Producers or autotrophs make their own organic molecules.
3. A food web is a sequence of organisms through which nutrients and energy pass as one organism eats another.
4. The trophic levels refer to the different levels or steps in the energy pathway.
5. The same organism species can be at different trophic levels.
6. Two way interaction.

Question 11

What is the first trophic level in the soil food web and what are some characteristics of this trophic level?

Answer 11

They are the Primary producers. They use photosynthesis. Root exudates into rhizosphere: It is the key mediator in the interaction between plants and microbiota.

Question 12

What is important about the rhizosphere?

Answer 12

Most microorganisms are around the rhizosphere because of the exudate released by the living roots.

Question 13

What types of organisms make up the second trophic level?

Answer 13

1. Herbivores: Eat living plants.
2. Detritivores: Eat dead plants.
3. Saprophytic microorganisms: Bacteria, fungi and archaea that live on dead organic matter.

Question 14

What types of organisms make up the third trophic level?

Answer 14

1. Microbes: Bacteria, fungi, archaea.
2. Carnivores: Animals feeding on other animals.
3. Microbivorus feeders: Organisms that feed on microbes.

Question 15

What types of organisms make up the highest trophic levels?

Answer 15

1. Predators: Animals that eat other animals.
2. Microbial decomposers.

Question 16

What are the 6 benefits of a healthy soil food web?

Answer 16

1. Nutrient cycling
2. Nutrient retention
3. Improved structure, infiltration and water holding capacity.
4. Disease suppression
5. Degradation of pollutants.
6. Biodiversity

Question 17

Explain nutrient cycling.

Answer 17

Nutrient cycling when organisms convert nonusable forms of nutriengts to usable form of nutrients for plants.

Question 18

How is the soil food web measured?

Answer 18

1. Counting
2. Measuring activity levels
3. Measuring cellular constituents.