3 Decomposition the Process Decomposer ~ an organism that feeds on and breaks down the deadMold ~ a fuzzy growth, a fungusBacteria~ single-celled life forms that can reproduce quicklyFungi ~ a group of organisms that lack chlorophyll and obtain nutrients from dead or living plants or animalsSpores ~ seeds of mold or fungi
4 Decomposition Experiment The ProcessI placed a piece of food into small, clear boxes. Then a few drops of water was added to the material and covered it. There were several observations made of the processes occurring. This experiment lasted for three weeks. However it is part of a larger ongoing study.The End ResultsThe food materials began to get covered with decomposers like mold, bacteria and fungi. Very close observations showed several spores around the boxes. The food items began to breakdown and soften and get wet and slimy looking.
5 There are 3 levels of Decomposers First Level DecomposersBacteria do the majority of the work and are the primary decomposer organisms of a compost pile. Thereare three types of aerobic (oxygen-requiring) bacteria. 1) Psychrophilic bacteria (thrive in lowesttemperature range - 55 degrees F or less) give off a small amount of heat as a by-product, causing a rise inthe pile's air temperature. 2) Mesophilic bacteria (thrive at degrees F) do most of the work and alsogenerate heat as a by-product, raising the pile temperature even more. 3) Thermophiles (thrive atdegrees F) work fast and last only 3-5 days.• Actinomycetes (higher form of bacteria similar to fungi and molds) liberate carbon, nitrogen and ammonia,making nutrients available for plants. They take over during the final stages of decomposition, oftenproducing antibiotics that destroy bacterial growth.• Fungi also take over during the final stages of composting when the organic material has been changed toa more digestible form.
6 Second Level Decomposers Second level decomposers include protozoa, rotifera, nematodes (roundworms), earthworms, millipedes, sow bugs,land snails and slugs, springtails, feather-winged beetles, mold mites and beetle mites. They consume the first leveldecomposers. Some second level decomposers, such as earthworms, also consume the organic residue, so theycan also be considered first level decomposers.
7 Third Level Decomposers Third level decomposers include ground beetles, centipedes, pseudoscorpions and ants (ants are usually not foundin a compost pile that contains adequate moisture - they are a sign that the pile is too dry). They feed upon first andsecond level decomposers. Some may also consume organic residue.
8 Decomposition for Life CompostingWhat is it?Controlling the natural recycling system of decomposition, which converts organic material into a dark soil-like material called compost.The ProcessA compost pile decomposes because a food web of living organisms feed on organic waste and each other to survive. Nitrogen (an important nutrient for growth) cycles through the living and nonliving components of a compost pile.
9 Who does the workSoil organisms do most of the work. Our work as composters is to givethe decomposers food, air, water and a good home - they eat our garbage and turn it into compost.• Soil organisms: microorganisms (bacteria, actinomycetes), molds, fungi, earthworms, insects
10 What do the soil organisms need? The same things we do - food, air, water, and a habitable temperature,which means making a large enough pile to keep them from freezing to death in the winter.• Food. Organic material - general rule of thumb - anything that was once alive can be composted, forexample, paper can be composted because it was originally a tree. Some organic materials, such as meatand dairy products, can create odors so they should not be added to a compost pile. Discuss what shouldand should not be composted. Explain recipe of 3 parts brown (high carbon) to 1 part green (high nitrogen)(all brown is ok; all green is NOT ok). (Refer to additional handouts for more information on carbon: nitrogenratio). Material will decompose faster if chopped up or shredded (increased surface area for bacteria tocolonize).
11 Summary of CompostingComposting is the managed accelerated decomposition of plant-based matter.A productive compost pile is built with layers, is turned (to add air) regularly, and is kept uniformly damp (NOT WET) so that consumers living in the pile can grow and reproduce.Decomposition is the breaking down of once living matter into soil, air, and water.The Nitrogen Cycle ~ nitrogen (an important nutrient for growth) cycles through the living and nonliving components of a compost pile.The Food Web of the Compost Pile shows how a compost pile decomposes because a food web of living organisms feed on organic waste and each other to survive.
12 Things we Do and Do Not Compost Leaves, grass, weeds, small garden clippings, pine needles, wood ash, bark, nutshells, fruit and vegetable scraps (peels, skins, or seeds), coffee grounds (including the paper filter), tea bags, sawdust, newspaper, paper towels, napkinsMeat, fish, bones, dairy products, vegetable oils, fats, human or pet waste, charcoal ash, plastic food packaging and glass containers
13 Why Compost? By composting we: reduce landfill space used. Leaves are not hauled to a landfill, but composted into nutrient-rich soil instead.save energy while reducing pollution. Fewer trucks are needed to haul waste. Fewer factories are needed to produce chemical lawn/garden/plant fertilizers.save money. Waste hauling fees are lower and less money is spent to buy fertilizer for lawns and plants.get exercise. Turning a compost pile is aerobic for the consumers in the pile as well as you! Think of it as Environmental Jazzercize!Produce valuable soil supplement; return organic matter to soilSave on not having to buy bags