BIOTECHNOLOGY - V. H. Herasymenko - 2006

Part II. Special Biotechnologies

Chapter 23. BIOTECHNOLOGY OF ORGANIC WASTE UTILIZATION BY VERMICULTIVATION

23.4.METHODS FOR FORMING BEDS AND TECHNIQUES FOR INTRODUCING THE BREEDING STOCK INTO THE SUBSTRATE

After the Fermentation process is complete, the waste is placed into beds to serve as a base substrate or feed. It performs several Functions: it protects the earthworms from the underlying soil, which is why its thickness varies from 15 cm in summer to 25-30 cm in winter. In addition, it acts as a feed for the worms, and must contain an adequate amount of Cellulose (20-25 %), and maintain optimal moisture (70-80 %), Temperature (19-20 ^оС), and acidity (6.8-7.2).

Following placement, the base substrate is continuously moistened once a day for 4 days (twice a day during dry weather), and then weekly for 30 days. This ensures the leaching of uric acid residues from the substrate, the dissolution of calcium carbonate to neutralize excessive acidity, oxygen saturation, and the maintenance of optimal moisture levels.

Simultaneously with watering, the temperature and acidity in the beds are measured. The optimal temperature is 19-20 ^оС, and the pH is 6.8-7.2. Increased acidity is corrected by applying slaked lime or chalk to The surface of the substrate (300 g/m²), followed by thorough watering so that the Water penetrates the entire depth of the substrate.

Each batch of organic substrate placed into the beds is tested for acidity using litmus paper or a pH meter. A strip of litmus paper, along with a lump of moist substrate, is held in a closed fist for 20-30 seconds and then compared with the reference color chart on the packaging.

The moisture content of the substrate is determined using appropriate instruments or organoleptically. In the latter method, a handful of substrate is taken and slowly squeezed. If no moisture seeps between the fingers, the substrate is too dry; if liquid drips from the palm, it is waterlogged. Waterlogging most frequently occurs during periods of prolonged rainfall. During such times, the beds should be covered with plastic film or straw mats.

Thirty days after placing the base feed, the beds are populated with earthworms. However, before doing so, all parameters (moisture, temperature, acidity) must be measured again, and the 50-earthworm test (the 50-worm test) must be conducted. The Essence of the test is as follows: a base substrate and 50 earthworms are placed into a wooden box measuring 50 x 50 x 15 cm with drainage holes, or into a 2-4 liter container, where they are kept for 24 hours at a temperature of 20 ^оС. Afterward, they are collected, counted, and their condition is assessed. If all worms are alive and exhibit normal mobility, this indicates that the feed is suitable for the earthworms. In the event of their death, sluggishness, or passivity, it is necessary to thoroughly verify whether the substrate has completed the fermentation process and re-evaluate all parameters (moisture, acidity).

In addition to the 50-worm test, a simpler biological indicator can be used. Several dozen earthworms are released onto the surface of the substrate. If they quickly burrow into it, this indicates that the substrate is suitable as feed. If the worms crawl across the surface and fail to burrow, the substrate is deemed unusable.

The beds are populated with earthworms along with the compost in which they were kept. They are distributed evenly across the surface of the bed either mechanically or manually using a 4-tine fork with rounded edges. Inoculation is carried out during daylight hours, as earthworms are photophobic and quickly submerge into the substrate. Afterward, the surface of the bed is moistened and covered with straw or burlap.