72. WHO NEEDS OIL? SHIT IS FERTILIZER

"Fertilizer is made from oil" is one of the most obnoxiously repeated lies in the peak oil community. Fertilizer is not made from oil, it is made from natural gas, coal and mined minerals (see #28). But what will we do when we run out of those resources? We will turn to our own urine and excrement.

Composting is a subject which futurists and back-to-the-earthers can all agree on. It is critical for ordinary life on earth, as well as for space travel and understanding sealed, cyclical biospheres. It drives me crazy that people have such strong childish taboos about a subject which is so critically important. We need to hire an army of ecologists and do a manhattan project on the human shit cycle tomorrow.

There is a fascinating old book I read once called "Farmers of Forty Centuries" by F.H. King. I believe it was written in the early 1900s, and describes a trip the author (an American) took to China to inspect its agriculture system. Shit was an extremely valuable commodity in the cyclic Chinese system. It even went to the point where a little boy would ride on the back of an ox while it worked driving an irrigation pump. His job was to collect the ox's shit in a ladle. There was a photo of that in the book.

The book (without photos) is in the public domain, and available on line here:
Farmers of 40 Centuries

Here's a quote:

One of the most remarkable agricultural practices adopted by any civilized people is the centuries-long and well nigh universal conservation and utilization of all human waste in China, Korea and Japan, turning it to marvelous account in the maintenance of soil fertility and in the production of food. To understand this evolution it must be recognized that mineral fertilizers so extensively employed in modern western agriculture, like the extensive use of mineral coal, had been a physical impossibility to all people alike until within very recent years. With this fact must be associated the very long unbroken life of these nations and the vast numbers their farmers have been compelled to feed.

This is also a great link: Civilization & Sludge: Notes on the History of the Management of Human Excreta

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In Calcutta, they've been culturing fish protein from sewage for about 100 years. Basically, they let the sewage flow into a shallow pond, where it causes an algae bloom. Apparently, this clears the water of human pathogens. Then, after a delay for re-aeration, the pond is stocked with fish like carp and tilipia. Systems like this can yield 2.8 metric tons of fish per hectare, per year. The "feed" is human and animal waste. See: Sewage Fed Aquaculture Systems of Kolkata: A Century-old Innovation of Farmers(pdf).

Fish from Shit


Open channel through which sewage is flown.
Lush growth of Colocasia seen on either side of the channel

From another article on shit-based fish culture:

Cities consume resources and produce both liquid and solid waste. The disposal of these wastes is increasingly becoming a problem. However, waste must be regarded as a resource for the sustainable urban development. Agriculture has always been an intrinsic part of Asian cities. In many Asian cities, the composting of separated solid waste and recycling of waste and sewage water used to be a tradition. These conventional methods are being renewed as urban agriculture is found to be providing employment, food and nutrition, land management and environmental improvement.

Kolkata (formerly Calcutta) has one of the largest recycling zones in India with age-old practices of fish culture and vegetable production. A large number of sewage-wastewater-fed fisheries have been developed on the wetlands in lagoon types of ponds in which fish are cultivated, and where sunlight, water hyacinths and phytoplankton are used to clean the water.Source.