Composts carbon-nitrogen ratios

Initial carbon-nitrogen ratios (by mass) hetween 35 and 50 are optimum for aerobic composting. At lower ratios ammonia is given off Biological activity is also impeded at lower ratios. At higher ratios nitrogen maybe a limiting nutrient. 

Composting was the channel by which many of the plant nutrients were prepared for application to the soil. Many of the waste plant materials were weedy with wide carbon-nitrogen ratios, and the oriental farmers learned early that such materials can be utilized... 

Measure the quality of the compost soil for maturity, percentage of solid, pH, moisture content, carbon/nitrogen ratio, temperature. 

Several researchers emphasized that compost is also an excellent material to use to prevent the acidification and the deterioration of soil productivity [8, 51-54]. Several factors including moisture content, temperature, aeration rate, and carbon to nitrogen ratio have direct influence on composting process, which has been reviewed in detail in the past. 

A buried corpse surrounded by plant material (e.g., straw, pine branches) can display a more rapid rate of decomposition than a cadaver buried without these materials (Mant 1950). Mant (1950) believed that these plant materials introduced additional bacteria into the burial environment while providing a layer of air between the cadaver and the soil. Also, an increase in the rate of cadaver decomposition following the addition of plant material is due to the widening of the carbon to nitrogen ratio, which promotes microbial activity. In fact, this is the premise behind the composting of dead animals (Elwell, Moller, and Keener 1998). 

Composting, the preferred method of stabilizing manure, is a controlled process in which nitrogen-containing materials are mixed with a carbon-containing source to produce a substance preferably in a carbon-to-nitrogen ratio (C N) of 30 to 1. Compost temperatures must reach 131-170Tforl5days, and be turned a minimum of 5 times to aerate the pile. 

The samples were prepared by adding 100 grams of plastic sample to 600 grams of mature soil compost in a 5-liter glass jar. The mature compost, 2-3 months old, had a pH of 8.7, ash content of 35%, and Carbon/Nitrogen (C/N) ratio of 10. The C/N ratio was calculated based upon carbon dioxide and ammonia measurements taken with the Sol vita instrument on the compost at the beginning of the test. Solvita is an easy-to-use test that measures both carbon dioxide (CO2) and ammonia (NH3) levels in the soil and also indicates a Maturity Index value. The index is useful for maturity level of the compost soil (Solvita Test Kit 2013). The blank compost had a Solvita overall maturity index of 7... 

NIR was applied to determine the moisture, carbon, nitrogen, and lipid contents and C-to-N ratio in a compost sample during the tofu (soybean curd) refuse compost fermentation (29-31). Control of the moisture content of the compost fermentation process and simultaneous measurement of the carbon, nitrogen, and lipid contents and C-to-N ratio in the compost were also attempted. The compost sampled from the composter was put into a polyethylene bag, and it was placed in a sample holder. The reflectance values were measured with a NIR spectrophotometer (NIRS6500SPL). 

Composting requires special conditions, particularly of temperature, moisture, aeration, pH and carbon to nitrogen (C/N) ratio, related to optimum biological activity in the various stages of the process [9],... 

C-to-N ratio of the compost calculated based on the values of the carbon and nitrogen contents of the compost is also an important indicator of compost fermentation. The predicted values of C-to-N ratio with NIR were in good agreement with the values obtained by the conventional method. 

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