Vermiculture, Hydroponics, and Related Forms of Sustainable Agriculture
This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Environmental Science. Please check back later for the full article.
Charles Darwin’s 1881 publication of The Formation of Vegetable Mould Through the Action of Worms sparked some of the most interesting research ideas on the utilization of earthworms. The evolution of their uses can be traced from ancient times, when earthworms were revered as soil organisms that could predict weather patterns, up to the first decades of the 21st century, when earthworms are considered one of the most versatile creatures for recycling organic wastes, a protein source in feedstock formulations, an active ingredient in pharmaceuticals, dynamic organisms in bioremediation, and the main organisms that drive the production of potent organic soil amendment. Vermiculture is the art, science, and industry of raising earthworms for any of the above-mentioned purposes. Vermicomposting is the art, science, and industry of the utilization of certain species of earthworms (out of more than 9,000) to manage organic wastes to produce soil amendments called vermicomposts. Research has demonstrated that many vermicomposts can accelerate germination, increase growth, and enhance yield of plants in the greenhouse, even at low substation rates in plant growth media. When utilized as a supplemental organic amendment in the field, vermicomposts can increase the growth and yield of crops. A number of reports have demonstrated the ability of the vermicomposts to suppress pests and diseases. These suppressions have been attributed to the rich microbial population and the diversity of microorganisms of vermicompost, which is contributed by the mesophilic process itself, allowing microorganism to multiply in orders of magnitude, unlike the traditional thermophilic composting process. The presence of other plant growth regulators, such as plan growth hormones and humic acids, also have major contributions to the positive effects of vermicomposts on plant growth and yield. Aqueous extracts from vermicompost, referred to commonly as “tea,” have been reported to produce positive responses of plant growth and yield, and suppression properties have been explored. More currently, vermicomposts have been used in alternative soil-less plant production techniques such as hydroponics. When used at very low rates in hydroponics and with much-reduced nutrients from inorganic sources, vermicompost tea application can produce plant yields equivalent to those raised in full inorganic fertilizers.