Compost can be categorized as a soil amendment derived from the metabolism of an organic substrate by aerobic or anaerobic microbes under controlled conditions. To produce high quality of compost, we should know how to measure the characteristics of successful compost. There are some aspects that we need to give more attention in a way to produce a successful compost. They consist of pH, nutrient content (N-P-K), moisture content, oxygen content, compost odor, compost colour, the texture and temperature.
From the practical, we were able to collect the parameters of the compost. They include the texture (particle size), compost colour, compost odor, pH and moisture content. For the first day of composting, effective microbe is added into the compost to enhance good bacteria and reduce pathogen. Ash will increase cation exchange capacity (CEC), therefore it will able to hold more nutrients in the soil. Lime will stable the pH in the soil and booster or stardex will enhance the growth of the good bacteria. Basically, booster is added with the combination of living bacteria, EM. Molasses also is added to enhance the growth of EM. Proper amount of EM is required as excess EM will damage the compost, resulting unpleasant odor of the soil and limited EM will reduce the quantity of EM.
Basically, compost is ready to use after 28 days. The effects of added organic matter to the soil will increase the water holding capacity, increases in infiltration rate and better soil tilth following composting. The important aspects including oxygen and moisture content and also substrate. One of the important factor is the ration of carbon to nitrogen (C:N) in the soil. Both are needed by microbes in the composting process. Too much carbon means that there is not sufficient N to fulfill the microbes’ need while too low carbon means that is more N microbes can decompose. The compost odor will have a bad odor. Optimum is a C:N ratio of 25:1 to 30:1 for composting. In addition to the C:N, the quality of the substrate in terms of chemical and physical composting is very important. For example, carbon in compounds resistant to microbial attack will be composted at a much slower rate compared to the carbon of simple sugars.
Physical properties of the substrate such as texture and size particle will affect the composting through their effects on oxygen availability. Texture refers to the available surface area for microbial action and this is important because most microbial activity occurs in a thin layer of water surrounding the particles. As we know, composting is an aerobic process because microbes involved require oxygen to live. Therefore, it is necessary to provide an adequate supply of oxygen by turning the pile of compost. The oxygen content in the pile needs to be at least 5%. If anaerobic (low oxygen) conditions develop, a different microbial community will inhibit the compost pile, resulting the reduction of efficiency of process and producing undesirable chemical compounds.
At the end of this practical, moisture that has been measured is 7 which means the compost is slightly wet. This is due to the excess molasses. Moisture should be in between 40% until 65% because sufficient water is required to meet microbial needs without restricting air movement in the pores. A simple “feel” test is used to measure moisture level in the compost pile. If water can be squeezed out by hand, the pile is too wet. If a handful does not feel moist, therefore the pile is too dry. Adequate moisture is the moist common limiting compost process and moisture can be added at the moment of turning the pile. The pH value for the soil that has been measured is 5.8 which is normal pH for compost. Most compost has a pH of between 6 and 8. pH is adjusted through the use of materials such as lime (alkaline) and sulfur (acidic).
As a conclusion, compost use in field crops should be part of any long-term crop management plan because composting helps farmers to manage manure from livestock farm. Other than that, it has agronomic benefits and it also controls plant diseases and adds nutrients to the soil. All students were able to produce compost from goat’s manure as part of waste management and produce agricultural wastes into quality organic manures.