Compost must be kept moist. A dry pile will not work — it will just sit there and look bored. It's amazing how much moisture an active compost pile can absorb. When people who don't have any experience with compost try to picture a humanure compost pile in someone's backyard, they imagine a giant, fly-infested, smelly heap of excrement, draining all manner of noxious, stinky liquids out of the bottom of the compost pile. However, a compost pile is not a pile of garbage or waste. Thanks to the miracle of composting, the pile becomes a living, breathing, biological mass, an organic sponge that absorbs quite a bit of moisture. The pile is not likely to create a leaching problem unless subjected to sustained heavy rains — then it can simply be covered.
Why do compost piles require moisture? For one thing, compost loses a lot of moisture into the air during the composting process, which commonly causes a compost pile to shrink 40-80%". Even when wet materials are composted, a pile can undergo considerable drying.12 An initial moisture content of 65% can dwindle down to 20 to 30% in only a week, according to some researchers.13 It is more likely that one will have to add moisture to one's compost than have to deal with excess moisture leaching from it.
The amount of moisture a compost pile receives or needs depends on the materials put into the pile as well as the location of the pile. In Pennsylvania, there are about 36 inches (one meter) of rainfall each year. Compost piles rarely need watering under these conditions. According to Sir Albert Howard, watering a compost pile in an area of England where the annual rainfall is 24 inches is also unnecessary. Nevertheless, the water required for compost-making may be around 200 to 300 gallons for each cubic yard of finished compost.14 This moisture requirement will be met when human urine is used in humanure compost and the top of the pile is uncovered and receiving adequate rainfall. Additional water can come from moist organic materials such as food scraps. If adequate rainfall is not available and the contents of the pile are not moist, watering will be necessary to produce a moisture content equivalent to a squeezed-out sponge. Graywater from household drains or collected rainwater would suffice for this purpose.
Compost requires the cultivation of aerobic, or oxygen loving, bacteria in order to ensure thermophilic decomposition. This is done by adding bulky materials to the compost pile in order to create tiny interstitial air spaces. Aerobic bacteria will suffer from a lack of oxygen if drowned in liquid.
Bacterial decomposition can also take place anaerobically, but this is a slower, cooler process which can, quite frankly, stink. Anaerobic odors can smell like rotten eggs (caused by hydrogen sulfide), sour milk (caused by butyric acids), vinegar (acetic acids), vomit (valeic acids), and putrification (alcohols and phenolic compounds).15 Obviously, we want to avoid such odors by maintaining an aerobic compost pile.
Good, healthy, aerobic compost need not offend one's sense of smell. However, in order for this to be true, a simple rule must be followed: anything added to a compost pile that smells bad must be covered with a clean, organic, non-smelly material. If you're using a compost toilet, then you must cover the deposits in your toilet after each use. You must likewise cover your compost pile each time you add material to it. Good compost toilet cover materials include sawdust, peat moss, leaves, rice hulls, coco coir and lots of other things. Good cover materials for a compost pile include weeds, straw, hay, leaves and other bulky material which will help trap oxygen in the compost. Adequately covering compost with a clean organic material is the simple secret to odor prevention. It also keeps flies off the compost.
Dehydration will cause the compost microorganisms to stop working. So will freezing. Compost piles will not work if frozen.
^BENEFITS OF COMPOST^
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