This last Tuesday Barton Community College held the 8th Annual Jack Kilby Science Day (JKSD). Most everyone in the area is familiar with who Jack Kilby was and his huge contribution to our modern society and its reliance on computer technology. You likely have read about the JKSD in this paper. “Hands-on” topics ranged from Forecasting Severe Weather, Music, Physics and Technology, and Physics Magic to Crime Scene Analysis, Internet and World Wide Web history since 1960, Soils, and Duck Wing Identification. Let’s discuss a bit about what the students learned in soils.
· Excluding food produced from oceans and lakes, most food, plant and animal, is directly and indirectly produced on soil. The part of the soil we rely on is about 2 feet deep give or take. The distance from the soil surface to the center of the earth is about 4,000 miles. That two feet we rely on is 0.0000009% of that distance.
· About two-thirds of the Earth is covered with water. Only about 10% of land is used for growing crops and about 25% for pasture and foraging of plants for food.
· Depending on the source, at least 40% of our crop land has been degraded to one extent or another. This is typically erosion or another problem like salinity.
· The previous facts point out why so much effort and energy is devoted to maintaining and improving our soils through concepts like conservation tillage. While erosion is less than it was, it is still a serious problem in the United States. To stress this point, it takes on average 500 to 1,000 or more years to produce an inch of topsoil while an inch can be lost in a single erosion event over a very brief period of time. In fact in many parts of the U.S., farmers are farming subsoil which is not as productive and requires higher input levels.
· It takes water to produce food, fiber, and fuel. While the Earth is blessed with a lot of water, much of it is unavailable for human consumption or crop production. Most water is in oceans in the form of salt water. Estimates are that at any given time, 97.5% of all water is salt water. Of the 2.5% remaining fresh water, almost 70% is in a frozen form and almost 30% in groundwater and things like permafrost. That leaves less than 1% in lakes and rivers. Only a fraction of the total water is in the atmosphere at any given time and when precipitation falls, it doesn’t necessarily fall on our crops or can runoff. Add into this that in many areas that irrigate whether surface or groundwater, the supplies are decreasing.
· And all of this doesn’t even take into account the weather for any given area and the growing season of that area each year. The lesson here for all of us is that we are currently feeding, at least trying to feed, over six billion people on a fraction of the earth’s surface and an even smaller fraction of the total water supply.
The take home message for the students at JKSD in the soils section as they learned soil texture by feel was twofold:
· In spite of these challenges modern agriculture has done more than any other sector to allow us our modern way of life and allowed over 95% of our citizens to work off the farm.
· To meet the ever increasing demands of a growing world population, all of us must jealously work together to guard these resources.