Composting Essentials and Methods for Judging Maturity Explained

a. Temperature control: During the composting process, the temperature rises rapidly above 60°C in the early stage, which can killpests and diseasesand weed seeds, etc. Afterward it naturally cools to around 40°C to 50°C, at which point it can be used to propagate beneficial microorganisms. Factors affecting temperature rise and fall include: 1. Moisture adjustment: The amount of water can affect the rise and fall of temperature. An appropriate amount of water can make the compost temperature rise, but too much water will create anaerobic conditions and lower the temperature. When there is too much water, add dolomite powder, dry rice husk charcoal, zeolite powder, rice husk powder, coarse sawdust, spent mushroom substrate (mushroom cultivation waste), etc., and increase the number of turnings. 2. Excessive aeration: When using a blower to pump air to promote aerobic fermentation, if there is enough water and air is pumped, the temperature will rise. When the temperature is too high, nitrogen loss and odor are likely, and it may even burn and carbonize, so aeration should be reduced to regulate it. 3. Carbon-to-nitrogen ratio and its timeliness; when the coarse fibrous material is mostly such that the carbon-to-nitrogen ratio is too high, fermentation is slow and the temperature is too low. At this time, high-nitrogen materials such as chicken manure, soybean powder, fish meal, distillers' grains, urea, ammonium sulfate, etc. can be added to raise the temperature. If after adding high-nitrogen materials the temperature still cannot rise, check whether the supply of water and air is correct. If the temperature still does not rise, molasses and starches and other easily decomposable fast carbon sources must be added to make up for the shortcoming of slow decomposition of coarse fiber. 4. pH: pH 5.5-8.0 is all suitable for compost fermentation. If the pH value is too low, the temperature will drop. Usually the pH value drops in the early stage of composting, and afterward gradually rises to neutral or slightly alkaline. When the pH value is too low, a small amount of slaked lime, oyster shell powder, rice husk charcoal, silica slag, dolomite powder, etc. can be added. b. Deammoniation treatment: If the pH value is too high (above pH 8), it will cause deammoniation, but the causes of deammoniation during compost fermentation are usually: 1. Carbon source supply is not timely: Microorganisms use the decomposition of carbohydrates to obtain energy, and use it to synthesize nitrogen elements into amino acids, etc. as raw materials for "protein synthesis." When the carbon-to-nitrogen ratio is too low or the carbon source decomposes too slowly (such as lignocellulose), microorganisms cannot obtain enough energy to convert nitrogen compounds (ammonia compounds) into organic nutrients, resulting in a large amount of residual nitrogen sources being broken down and causing deammoniation. At this time, molasses and starches should be added to provide the urgently needed carbon source, so that the excess nitrogen source can be digested in time to stop the continuation of deammoniation. 2. Decomposition speed is too fast: When there is too much water or air, fermentation is vigorous. When the temperature rises above 60°C, the decomposition rate of organic matter is too fast, and deammoniation will also occur. At this time, aeration should be stopped, water should be added, and zeolite powder should be added while turning the pile frequently, which can lower the temperature and stop deammoniation. 3. Unsatisfactory microbial community: Beneficial soil microorganisms can effectively use nitrogen sources and convert them into stable organic fertilizer components, and can also appropriately use them for resynthesis and retain them in the microbial cells, avoiding the breakdown of excess organic matter and deammoniation. Microorganisms (nitrifying bacteria, photosynthetic bacteria) can even use ammonia gas to produce nitrate nitrogen and ammonium sulfate, etc., for plants to absorb. Therefore, when deammoniation occurs, in addition to the above countermeasures for carbon-to-nitrogen ratio, water, air, fermentation speed, etc., the most important thing is still to supplement a large amount of beneficial microbial communities. Judging maturity: 1. Temperature: Add water to moisten the compost, leave the whole bag for two days; if fully mature, it will no longer generate heat or will be only slightly warm. 2. Smell: After moistening with water (about 60%) for three days, if fully mature, there should be no foul odor. 3. pH: Fully mature compost is close to neutral or slightly alkaline. 4. During the fermentation process, sample and test the decline in the C/N ratio.