What About Fertilizer?

Posted by on Sep 11, 2013 in Blog, Uncategorized | 0 comments

What About Fertilizer? Now you might be saying, “but what about fertilizer. Donʼt farms fertilize the land?” Well yes they do, but it may not be really helping the soil in the long run. “Soils are complex systems,” Karr says. “And this fact holds true when considering the plant availability of mineral nutrient elements. Fertilization with highly soluble commercial sources of nutrients has an effect on the plant availability of other nutrients. For example, heavy fertilization with ammonium-N may reduce potassium availability. High levels of ammonium-N or magnesium can reduce calcium availability. However, when high amounts of macronutrients are applied, often micronutrient availability is adversely affected. High applications of nitrate-N may reduce iron availability. Long term phosphorus application will reduce zinc availability and, to a lesser extent, iron availability.” Calcium, potassium, magnesium, and zinc are all minerals that the human body depends on. Big science and big ag are failing to see the interdependence of all of the aspects of the soil. It isnʼt that plants just take out a few things and we can spray and put them back in the soil. Nature is much more complicated and smart. To make matters worse, there is no real financial incentive to fix the problem. Corn is sold by weight and volume not by mineral content. Imagine if farmers had to produce mineral rich food. They couldnʼt. Karr concludes his paper by saying, “Mineral nutrient depletion continues to be a problem in U.S. farm, forest and range soils. This depletion is caused by natural processes, such as weathering and erosion, particularly in the sensitive soils of the southeastern United States. More significantly, throughout the United States, human accelerated depletion is caused by the production of high yield crops and livestock grazing. Those activities cause nutrients to be removed and organic matter to be depleted from the soil’s natural cycling system. Moreover, when commercial growers attempt to replenish the soils of only some mineral nutrients by fertilization they may exacerbate mineral nutrient imbalances. While methods exist to replenish the soil of its mineral nutrients there is a relative lack of knowledge on how to identify all deficiencies and to fully correct them. In addition, the lack of an economic incentive to implement long term, soil-building solutions perpetuates the relative fragility and inconsistency of US soils’ nutrient supplying power.” The problem is not just in the US. Severe nutrient deficits of N, P, and K occurred widely in harvested areas in both developing and least developed countries, particularly in the rice and wheat production systems in Asia, Central and South America, and Africa. Continuous depletion of soil N, P, and K in most African countries and other least developed countries, coupled with low crop production levels, poses a real threat to agricultural sustainability and food security. Soil nutrient depletion caused by high production levels and decline in fertilizer use in recent decades in many developed countries are also a concern. Worldwide, soil fertility problems associated with the human-induced nutrient depletion are expected to...

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