Este miembro participó en las siguientes discusiones
Water scarcity and Closed Loop Recycling of Wastes
High organic matter soils are reservoirs for water and that reservoir can be made bigger thus making irrigation water go 5 or even 10 times further. As the world gets more populated, it produces more agricultural and urban wastes. As it gets richer, it produces more urban wastes. For the human race to survive, we have to recycle these wastes. Most, if not all crop wastes, and many (most in some areas) urban wastes can be recycled using aerobic digestion, i.e. “composting” and TAD (Thermophilic Aerobic Digestion – pumping air in to raise the temperature). It is easy to accept that crop wastes from farming, or green wastes from urban gardens can be composted, but so can many industrial wastes.
Take hard plastics out of consideration, they are difficult but many plastics can be successfully recycled. For example, urea-formaldehyde is the “glue” used to make boards for furniture manufacture and discarded chip-board and MDF (Medium Density Fibreboard) and, when shredded, are a very useful source of Nitrogen fertiliser and are helpful in composting other materials. Another example is a “base” plastic (used to manufacture a wide range of glues and consumer product plastics) is PVA – Polyvinyl alcohol. This is “rocket fuel” for the micro-organisms in a compost heap but it is not easy to handle. It is liquid at temperatures above 60 or 70 degrees C but becomes progressively sticky as it cools.
Much easier to handle are materials such as crop residues, green wastes from urban gardens or city arboricultural management, cardboard and tissues and some industrial wastes. A good source of Nitrogen fertiliser is sewage and thorough composting above 60 degrees C will control pathogens. (Turn the heap every few days until it gets to 60 degrees, turn again and get up to 60. Three or four times up to 60 will dramatically reduce pathogen transfer risk.)
I shall soon be introducing a regular series on a page at https://landresearchonline.com/
In the now-developed West, the change from subsistence farming to surplus production was dramatically accelerated by Harry Ferguson’s development of a three point linkage giving weight transfer – cultivations, weed control and husbandry greatly improved, land was released from feeding horses and labour reduced and progressively made available to the urban economy.
Today, in developing farm production in poor countries, manufactured fertiliser costs are high and, because of energy costs, will not get lower in time. Making fertiliser by composting urban wastes is an available technology which provides nutrients, reduces cultivation costs, reduces irrigation need, and progressively lowers crop diseases. It also provides a chargeable service to the urban economy. This “closed loop” economy sees urban wastes as a resource which can provide that trigger for rapid change and development, and is described in detail in “Survival; sustainable energy, wastes, shale gas and the land” by Bill Butterworth and available free for download at Amazon
The following is an over-simplification of the problems facing developing food production technology and delivery but there is a matter to be shared in this topic and that is in closed-loop nutrition, i.e. using urban wastes to provide the fertiliser to feed the people who produce the waste. Wastes contain a wider range, and larger amounts of trace elements than mineral fertilisers and, in effect, are Carbon neutral in production. (Bear in mind that UN-sponsored research showed that the electrical energy to make 1 tonne of Nitrogen nutrient in a modern USA factory is 21,000 kWh!) The human race has to take the urban waste route to nutrition if it is to survive. See the evidence and practical record of how it has been done safely in “Survival” by Bill Butterworth, Amazon and Kindle.