If not for microoganisms, the world would be covered with dead plants and animals. All dead and waste organic and inorganic material from living things is recycled when micro-organisms (saprophyte) decompose the dead and waste material - releasing the nutrients it contains into the air, soil or water. Nitrogen and Carbon are two essential nutrients recycled by micro-organisms.
Carbon cycle
Composting is the use of micro-organisms to decompose dead plant material in garden waste cycling the nutrients by making waste into nutrient rich compost used to promote plant growth. Micro-organisms make compost efficiently when they have moist, warm conditions with enough air,space and food to reproduce rapidly. Compost bins are designed to provide these.
As micro-organisms in the compost begin to decompose the organic matter and carry out aerobic respiration releasong heat energy the temperature rises. The temperature remains high during respiration and temperature decreases as decomposition is completed and micro-organisms die from lack of food or buildup of waste.
decomposition produces glucose which micro-organisms use for aerobic respiration. during respiration carbon from glucose is combined with oxygen to produce co2. This is released into the atmosphere for plants to use in photosynthesis, which continues carbon cycling.
Good airflow is important in composting so there is enough oxygen available for aerobic respiration and allow carbon cycling. If no oxygen is present and anaerobic respiration occurs, carbon remains in lactic acid.
Turning the compost increases the amount of oxygen in compost allowing aerobic respiration and heat is released which increases temperature. thermophilic microbes have a higher rate of respiration in higher temperatures. Turning compost allow microbe to break down matter more quickly. High temperature also kills pathogenic microbes and seeds in compost.
Bacteria are important in cycling carbon and nitrogen because plants need these for photosynthesis and respiration. Microbes carry out extracellular digestion breaking down dead and waste organic material . The microbes absorb nutrients and use them in respiration releasing co2 into the air which plants can use for photosynthesis. to make glucose. Glucose used in respiration to produce energy to make enzymes and chemicals needed for growth and reproduction.
Nitrogen compounds in compost are broken down by decomposers and changed into nitrates by nitrifying microbes. Plants absorb nitrates and use them to produce amino acids which becomes available to animals when they eat plants.