Decompostion

What is decomposition

the breakdown of organic matter into simpler inorganic compounds

Decomposition is essential for :

nutrient cycling soil fertility, and energy flow

Decomposition converts ______ to carbon dioxide, water, and mineral nutrients

detritus

What are the key players in decomposition

microorganisms

detritivores

scavengers

What are the types of detritivores

microfauna

mesofauna

macrofauna

megafauna

What are some examples of microfauna

bacteria, fungi, protozoa

What are some examples of mesofauna

mites, springtails

What are some examples of macrofauna

nematodes

What are some examples of megafauna

earthworms, snails, millipedes

What is the role of a microfauna

enzymatic breakdown of organic molecules

What is the role of a mesofauna

shred litter, increase surface area for microbes

What is the role of a macrofauna

fragment litter, mix soil

What is the role of a megafauna

ingest and mix soil

What detritivore is most important in soil structure

mesofauna

What detritivore is most known to enhance soil aeration

megafauna

What affects the rates of decompositon

temperature

moisture

oxygen availability

chemical quality

biotic community

Warmer temperature = ____ decomposition

faster

Colder temperature = ____ decomposition

slower

_____ conditions favor microbes

Moist

Too dry = _______

dormancy

Very wet conditions favors ______

fungi

Aerobic:

rapid decomposition

Anaerobic:

slow, partial decay

Simple sugar, amino acids:

decompose quickly

Ligning, cellulose, waxes, tannins:

decompose slowly

What are the types of biomes

tropical rainforest

temperate forest

grassland

boreal forest / tundra

wetlands

Rich soil fauna and microbial diversity:

faster decomposition

Disturbed or polluted soil:

slower decay

The decomposition process is a sequence of _______

physical and biological processes

What is the overall goal of decomposition

transform organic matter into inorganic nutrients

What are the different ways to transform organic matter into inorganic nutrients

leaching

fragmentation

microbial colonization

chemical breakdown

mineralization

humification

What is the pre decomposition step

DEATH

What happens upon death

cells lose ability to regulate water and ions

cell membranes begin breaking down

microorganisms begin colonizing dead material

In plants decomposition can occur _______ the entire organism is dead

before

What is leaching

soluble compounds dissolved and washed out of litter by water

What is an example of leaching

amino acids, salt, sugar

What is the importance of leaching

happens early in the process

leaching removes _____ soluble nutrients

easily

Leaching makes litter _____ and nutrient ______

lighter

poorer

Leaching is fastest in _______

wet, rainy environments

What is fragmentation

physical breaking down of litter into smaller pieces

What are the ways that fragmentation is done

shred, chew, ingest

Who does fragmentation

earthworms

termites

millipedes

beetles

Fragmentation increases ______ for microbes

surface area

Fragmentation mixes organic matter into the soil (_______)

bioturbation

During microbial colonization, microbes produce _______ that break down large molecules

extracellular enzymes

What are the extracellular enzymes that break down large molecules

cellulose, lignin, proteins

What is chemical alteration

microbes use enzymes to break down complex materials

Who does chemical alteration

bacteria, fungi

What are the targeted molecules of chemical alteration

cellulose, starch, proteins, lipids, lignin

What does cellulose, starch, proteins, lipids, and lignin turn into

sugars, amino acids, fatty acids

What is mineralization

conversion of organic nutrients into inorganic forms usable by plants

What is an example of mineralization

converting N into Nitrate

What is the process of mineralization

microbial respiration and enzyme activity release CO2, water, and minerals

What is the importance of mineralization

returns nutrients to the soil for reuse by primary producers

What is humification

formation of humus

What is the importance of humification

improves soil structure

Humification improves ______

water retention

Humification stores _____ long term

carbon

What is the 1st step of the decomposition pathway

dead organic matter

What is the 2nd step of the decomposition pathway

leaching

What is the 3rd step of the decomposition pathway

fragmentation

What is the 4th step of the decomposition pathway

microbial breakdoqn

What is the 5th step of the decomposition pathway

mineralization

What is the 6th step of the decomposition pathway

humification

What is the importance of recyclers

decomposers recycle nutrients back into the ecosystem

Most nutrients are used and reused multiple times within a _____

system

What would happen without decomposers

nutrients would remain locked in dead organic matter

Decomposers are part of the _____ food chain

detrital

Decomposers provide food for _____ food levels

higher

Decomposers prevent nutrients from _______

getting stuck

Decomposers get eaten by ______

predators

A tropical rainforest has _____ decomposition

rapid

In a tropical rainforest, nutrients are _______ and taken back up by plants

quickly recycled

In a tropical rainforest, the soil nutrients are ______

poor

Most nutrients in a tropical rainforest cycles up through ______

the biomass of trees

In an aquatic system, decomposition occurs in _______

sediment

In an aquatic system, decomposition regenerates nutrients for ________

algae and phyloplankton

Decomposition drives _______ in lakes and oceans

primary productivity

In an aquatic system, organisms receives organic matter from _____ the system

inside and outside

Why is autochthonous

algae, aquatic plants phytoplankton

Allochthonous

fallen leaves, woody debris, terrestrial plants

In shaded streams, there is a high concentration of _______

allochthonous

What is the name of the step in aquatic decomposition that is the breakdown of plant tissues in water

conditioning

Which of the flowing would have a fast decomposition rate?

a. Leaves with a high concentration of Tannins

b. Leaves with a high concentration of Lignin

c. Leaves with a high concentration of Proteins

c

Why are decomposer communities less studied

many species are microscopic or cryptic