The tidal wave of  modern farming chemicals is a new  phenomenon.   The modern petro-chemicals were developed since the early decades of the twentieth century.

Many people however say that we cannot go back to the old methods of ancient agriculture due to the low yields of such methods. However there are many instances of large populations of ancient peoples being sustained in the past in relatively good health.

There is a region of the Amazon in Bolivia that had a population of millions deep in the heart of the rain forest. These people constructed raised bed fields that were surrounded by water filled canals. The soil would be removed from the canals and deposited onto the raised fields. This would in fact double the depth of the thin rain forest soils. It would also re-fertilize yearly when the canals would be dredged to remove accumulated organic matter and fish wastes.

The high water level would ensure good moisture content of the soil. The water would also function as a heat sink absorbing the high tropical heat of the day, and releasing the same at night.

A good web site on this raised field system can be found at Ancient Raised Bed Agriculture  There is also a series of links that will take you to articles on the explorations in this part of the world.

Another site on a similar system of agriculture in Peru near Lake Titicaca is at Lake Titicaca Agriculture. This site is about a system of corrugated fields called Waru-Waru by the locals. This is a similar system to that of Bolivia. In this case however the water canals would provide additional frost protection on those cold Andean nights.

In both cases anthropologists interested in the population that such a system could support enlisted the help of local farmers to try renewing the fields. In both cases yields increased. In the Peruvian case yields per hectare for potatoes increased from the local norm of 2 to three tons to more than 8 tons.

This type of yield could indeed support large populations, and the fact that the Peruvian fields cover some 205,000 acres. This in itself shows a large labor population, and showcases the fact that large amounts of production are possible in these areas.

And for a really informative site go to Ancient Agriculture. International Ag-Sieve showcases many fine examples of ancient agriculture that gave high yields. Explained are the Hohokum canal and terrace systems, Sri Lankan terraces and water tanks, the Waru-Warus, and ancient Hawaiian aquaculture, along with others.

Ancient Pompeii and its lesser well-known sister city Herculaneum were covered by a volcanic explosion of poisonous gases and ash. This preserved the cities and their gardens as they were on that day in 79 AD. From this site Pompeii and Herculaneum City Gardens you can access some photos of the garden paintings these people used in their small city gardens to make the space appear larger. You can also explore the various uses these gardens served including religious, dining and entertainment.

And what about the fabled 'Hanging Gardens of Babylon'? Well, at Hanging Gardens of Babylon  you can see a bit of what may have been the idea behind this famous garden (which may or may not have really existed). It is said to have been built by an ancient King to placate his homesick wife who being from a green and mountainous country was languishing in the flat desolate Mesopotamian plains. This garden illustrates what we humans look for in our gardens, and place of peace, beauty and tranquility, within which we may escape the pressures and rigors of everyday life.

Now one of the most amazing of all ancient cities is high in the Andes mountains of Peru. There the 'Lost City of The Incas' otherwise known as Machu Piccu is located. At Lost City of The Incas one can see some beautiful photographs of the stone terraces that held the soil for the crops needed to sustain this cultural and religious center. The soil was actually laboriously carried up from the valley floor below in baskets to be deposited behind the terraces. The ingenuity of these people astounds the imagination. The celebrated stone masonry of their culture is nearly unrivaled in all civilization. At the bottom of the site click on the 'next' button to go to the next page, and so on.

The ancient Maya had an extensive culture that reached throughout much of Central America. A huge complex of well-maintained roads connected the large and small cities in this area. A system of canals, and water tanks ensured adequate water for the large population. At Maya Agriculture Study one can find a series of pages describing the archaeological digs at one of these sites. And a page showing how the ancient system of agriculture was hacked out of the jungle, and designed to be a long-lasting agricultural system that would last for generations.

So what about us nowadays? Can we feed the world with organic agriculture with our large population? Is it worthwhile to convert to organic agriculture as the dominant system to produce food? There are many that say not, that the world needs the large yields permitted by synthetic fertilizers and pesticides to keep full bellies in the lands. But what about those poor countries where the people cannot afford modern petrochemicals? What if they get cheap grains from the USA and it drives the prices of their own produce down to such lows that the farmers there cannot compete, and have to resort to cash crops such as coffee and bananas? Now they are getting some cash, but not growing foods for their families. If they went to organics they could sell their produce for higher prices, and also be able to increase their own bio-diversity by interplanting edible food crops between their gourmet cash crops. This way they can have the cash, and also grow local nutritious foodstuffs.
Also it must be understood that the high yields from synthetic chemical farming leads to some undue consequences to the soil in terms of the long term ability of the soil to yield at those high yields. Not only must the farmer continually add more fertilizers to the soil in ever-increasing amounts, the soil also is less likely to last for thousands of years of growing due to the fact that conventional agriculture encourages the soil to be uncovered for a large time each year. This uncovered soil is more likely to be blown away, or eroded by water. The soil lost by any conventional field is much higher than the soil lost by an organic soil in similar conditions.
   There is a very good web site which deals with this subject in depth, it can be found at Agriculture of the Future will be Organic .
They also have a good main page at  Don't Panic, Eat Organic with information on raptor perches and nesting boxes, as well as extensive listing of organic links all compiled by an organic farmer.

So we can see that not only was the ancient agriculture organic, but with modern organic methods, science and study we can match most ancient agricultural yields, and ensure that the Earth has enough good soil to ensure a healthy population without causing environmental degradation to produce our food.