Friday, July 15, 2011
The ancients thought that the universe was composed of four elements; earth, air, fire and water. Modern science teaches us, however, that many more elementary materials make up these elements. However, the ancients did understand that all these elements were inter-related and that man himself was a part of this great fabric of creation.
Either directly or indirectly, all food comes from the soil or the sea. There is little wonder then that from the earliest times of our existence we have wondered how plants transform the lifeless, inert, mineral material of soils into living tissues. It is one of the marvels of plant life that the same land, with the same supplies of moisture, air and sunshine, can support such a great variety of green plants. However, science has also shown that although there are a great variety of green plants in agriculture and the wild; their chemical composition is fairly similar. Green plants contain certain definite chemical compounds which are known as carbohydrates (starches & sugars), celluloses (woody fiber), fats and oils and proteins.
In order to make satisfactory growth green plants must obtain from the soil adequate supplies of mineral elements. Chemical analysis shows that green plants are from 90% to 98% organic or combustible material which they have manufactured from the gases of the atmosphere and moisture obtained mostly from the soil. Further analysis shows that the non-combustible substances (ash) found in green plants are derived from the soil where the plant grew. Of the twenty or more mineral elements, which are present in the soil, some are essential, such as, potassium, phosphorus, sulfur, iron, calcium & magnesium. Nitrogen, an essential element, however, is not derived from the minerals of the soil. The ultimate source of nitrogen is the atmosphere.
The problem of soil productivity depends upon the presence in the soil of sufficient amounts of each of the essential elements in soluble, or available, form. Fortunately, the “weathering process”, which is the effect of alternate freezing and thawing supplemented by the action of acids produced from decaying vegetation caused by the soil micro-organisms is continually acting upon the mineral matter of the soil to gradually produce chemical changes whereby the complex, insoluble compounds, which compose the soil minerals, are broken down into simpler, more easily soluble ones. With proper conditions of moisture and air, and an adequate supply of humus, or decaying vegetation and animal life in the soil, this process of changing the unavailable soil material into available nutrients goes on continuously.
In brief, two great processes are continuously working to create the food supply of this world. First there is the series of chemical changes making the minerals of the soil soluble, ready to be absorbed by green plants. These changes are set in motion by weathering and micro-organisms in the soil. Then follows the amazing process by which green plants manufacture from the air and water the organic compounds which create their own structures and become the food supply of the world.
This process is called photosynthesis. It is a process whereby the energy from the sun is converted into chemical energy inside the chloroplast of the green leaf. Carbon dioxide gas enters the leaf from the outside air by way of the stomata, which are on the underside of the leaf. There it meets with water which has been carried from the soil through the conductive system. Energy from the sun, in the presence of chlorophyll contained in the chloroplast is somehow used to unite the oxygen molecule, from the water and the air, with the carbon molecule, from the carbon dioxide of the air, to form a simple sugar, or carbohydrate. The carbohydrate that is produced is the building block for proteins, sugars, fats and oils that comprise the food supply of the planet. The chloroplast is the smallest and most important factory in the world. Man has not yet unraveled the process by which this is accomplished.
They are called carbohydrates because they are compounds of the element carbon, with hydrogen and oxygen. Sunlight, air and water, therefore, are the ingredients by means of which plants create and store the energy to fuel themselves and the world. When wood is burned this energy turns into heat, air and water vapor again. The energy that drives all organic beings, including man, is a part of this same process.
The chemical constituents of the soil along with air, water and sunshine, are inextricably intertwined in all organic beings. It would, therefore, follow that there is no demarcation line between chemical and organic substances in the processes that drive life. Green plants do not distinguish between basic elements derived from the minerals of the soil and mineral nutrients supplied by man in crop production. The application of both organic and inorganic nutrients to the soil is in harmony with the natural processes of the world in which plants exist.
No one can say how long it has taken man to develop from a primitive state to a comparatively civilized existence; but the time has been long. Great eons of time would have passed when man must have eaten anything and everything he could find to survive. The struggle to obtain food surely must have been his chief occupation. It is difficult to imagine the slow steps man made to gain the knowledge to improve his condition. As a result of observation, no doubt, came the knowledge that seeds sprouted and a plant grew.
It must have been a large step from this observation to the raising of crops.
Once man began cultivating crops he gained a greater control over his very existence. For untold ages the soil was worked, as best he could, to make favorable conditions for crop production. Most everything, including the manure of animals, was returned to the soil in his attempt to increase the productivity of his soil. He couldn’t have known it, but enormous populations of microorganisms flourished in the uppermost portions of the soil gaining their sustenance from the organic wastes that fell to the ground. One of the tenants on which the belief in the organic method of farming is based is that man is, in effect, mining the soil of its organic and mineral content and not replacing these elements, thereby impoverishing the soil. There is justice in this thought. Like all things in nature there is a cycle by which everything that has sprung from the soil should be returned to the soil. Once this cycle is closed there is no loss to the soils productivity.
It might be better for man to visualize the great connectivity of all things, from the earth, teaming with life, the sun, providing our energy, to the great structures of the vast universe extending beyond comprehension.
Our revels now are ended. These our actors
As I foretold you, were all spirits, and
Are melted into air, into thin air:
And like the baseless fabric of this vision,
The cloud-capped towers, the gorgeous palaces,
The solemn temples, the great globe itself,
Yea, all which it inherit, shall dissolve,
And, like this insubstantial pageant faded,
Leave not a rack behind. We are such stuff
As dreams are made on; and our little life
Is rounded with a sleep.
“The Tempest” Act 4, Scene I, 148-158Back