Composting
Composting is the method of degrading raw products in the presence of air into nutrient-rich and soil-friendly additives. The aerobic method is another name for this process. It is apparent that the whole degrading mechanism is aided by certain beneficial micro bacteria. As a result, the whole procedure takes longer than a few days, taking over a month to produce certain organic substances. Small pits or gaps may be used for composting. Composting is commonly accomplished by digging pits and filling them with organic materials. This produces humus -like substance that is often humid and dark by colour. However, just dumping the waste away would not result in decent compost; it must be kept under such parameters, such as temperature, moisture, and oxygen.
Compost is a bio-composite that increases the fertility of the soil and the productivity of farmers and gardeners. It is black and is therefore referred to as "black gold."
The process of composting
Composting occurs under 3 different stages : mesophilic , thermophilic, and maturing stage.
Mesophilic stage: Compost bacteria generate carbon dioxide and energy by combining carbon and oxygen. The microorganisms use some of the energy for growth and reproduction, while the remainder is released as heat. Mesophilic bacteria expand in a layer of agricultural waste as it starts to compost, bringing the temperature of the composting mass to about 44°C .
Thermophilic stage: This process starts as thermophilic microorganisms become very active and generate a lot of heat. This stage will last up to 70°C (158°F) though such high temperatures are not normal or desirable in backyard compost. This stage of heating is short-lived, lasting just a few days, weeks, or months.
Maturing stage: The microorganisms in this stage decimate and convert the raw materials, the process slows and the temperature drops. Mesophilic organisms are once again booming, displacing the majority of thermophiles. The compost then starts to cool and mature.That’s why this is often known as maturing stage.
Fig 1: different stages of composting
Organisms involved in composting
1. Bacteria – Bacteria are the micro organisms and are unicellular in nature. In the case of composting, bacteria are very useful because they help to break down the organic materials into fertile compost.
· Psychrophilic bacteria: Temperatures of around 13°C/55°F are ideal for these bacteria. A small amount of heat is produced by these bacteria. Even when the weather is cold, the right conditions can lead to the hotter conditions created by mesophilic bacteria.
· Mesophilic bacteria : Mesophilic thrive at warmer temperatures between 70 degrees F. and 90 degrees F. (21-32 degree C.). These bacteria are known as the aerobic powerhouses and do the majority of the work in decomposition.
· Thermophilic bacteria: Thermophiles take over when the temperature in the compost piles rises above 10 degrees F (37 degrees C). Thermophilic bacteria raise the temperature in the pile to a level where any weed seeds present are killed.
2. Actinomycetes: This is the well developed bacteria which is similar to the fungus and helps to breakdown the complex materials into fertile compost which were left by thermophilic bacteria under the moderate temperature.
3. Fungi: It helps in the process of breaking down the organic materials and often be active at the thermophilic stage.
Fig 2: components in composting
Necessary components for composting
1. Oxygen: For organic-waste composting, oxygen is a key parameter, and constant regulation of oxygen in a composting pile may be useful. A adequate oxygen supply can help compost stabilize and mature faster, but a lack of oxygen can lead to compost instability and biological hazard.
2. Moisture: Moistures or water is very important factor for bacteria to survive .However the moisture should be moderate otherwise bacteria may not survive in excessive and low moisture.
3. Organic matter: For actinomycetes and fungi to survive they need carbon and nitrogen whereas bacteria need potassium and phosphorus. Carbon acts as an energy whereas nitrogen helps in building the protein chains.
Due to the easy techniques and rich bio soil additive of compost it is not only used by farmers by profession but also used by the small farmers and gardeners. And thus people are getting attracted towards home gardening and farming techniques.
Sir Albert Howard in the development of organic farming
He firmly encouraged the recycling of all organic waste products, including sewage, back to agriculture, according to what he coined "The Law of Return." Howard's book “An Agricultural Testament” was released in 1943, and it addressed a principle that would become important to organic farming: the significance of utilizing accessible waste products to develop and sustain soil richness and humus .Later in India he described his own primitive way of composting. Being from the farmer family and a enthusiastic young Cambridge graduate he served as a mycologist in West Indies and contributed many theories and concepts of organic farming when he worked for 26 years in India.
Development of biodynamic farming and composting
Ehrenfied Pfeiffer who has met Rudolf Steiner(anthroposophist) at the age of 19 and he started to work and collaborate with him where he learnt different techniques about biodynamics and later on in 1928, Pfeiffer took charge of a farm of over 500 acres in the Netherlands. He was asked to work at Hahnemann Medical College in Philadelphia in the late 1930s, where he experimented with exploiting blood crystallization patterns to diagnose cancer. When the war broke out, Pfeiffer and his family relocated to Kimberton, Pennsylvania, where Alaric Myrin gave him the chance to establish a model biodynamic farm and training program. Pfeiffer was also the driving force behind the formation of the Biodynamic Farming and Gardening Association, as well as the publication of its journal.
Benefits of composting
Composting at home helps us to recycle garbage from trash and transform that into something useful for our gardens.
Composting increases the water retention capacity, productivity and resistance of the soil.
Farmers that use compost to promote healthy soil use less water and still produce more yields.
It also balances the buffer ph. of the soil because no harmful fertilizers are used there.
Composting is soil friendly and thus not harmful to the environment.