Friday, May 20, 2011

Losing Ground - Soil Depletion, a Fundamental Issue in Health



Dirt may have more to do with your health than you realize…

Healthy soil is made up of more than just dirt, water, and minerals. Soil is one of the most diverse and varied ecosystems on the planet. Some soils may contain up to one million species of microbes per gram. In addition, soil is home to many different species of invertebrates, such as earthworms, centipedes, millipedes, snails, slugs, nematodes, and many others. This makes soil easily the most abundant ecosystem on Earth.

Through the modern industrial farming practices of poor land use, such as deforestation, overgrazing, and improper construction activity, we have added stress to this diverse environment. Land is literally washing away due to erosion. Thousands of synthetic chemicals are sprayed onto farmland, only to wash out to sea wreaking havoc on marine life. We are literally sucking the life out of the very land that supports us. How did this happen?

When plants grow in the soil, they extend roots to absorb water and nutrition. These roots penetrate and probe the soil, taking up all the minerals they need to grow. In nature, the soil is re-mineralized by the breakdown of organic matter (e.g. plants, animals) by bacteria and creatures that live in the soil (e.g. earthworms, soil microbes). In this cycle, many of the minerals that the plants take from the soil are replaced when the plant dies, depositing that wealth back into the soil.

Animals that feed on plant life are also tied to this cycle. When an animal eats a plant, it is to absorb the nutrition the plant pulled from the earth. After the animal processes this food, it re-deposits the remaining compounds back onto the soil (think animal poop). Once there, these compounds can be feasted upon by the myriad soil based creatures and bacteria, themselves depositing more "waste" back into the soil. This animal (and bacterial) "waste" is highly nutritious to plants, whose roots probe the soil and absorb it to grow again. These natural cycles have supported plant and animal life on this planet for many millions of years.

Enter the humans...

Throughout the course of human history, we have been trying to find ways to increase production of food on our lands. Somewhere around 8000BC, agriculture became fairly well established and some basic truths presented themselves to us. Some soils will grow some plants better than others. Furthermore, if you keep growing the same crop in one location, year after year, then the soil suffers and less food can be grown on that parcel of land because the productivity of that parcel of land eventually decreases.

Early farmers experimented with many types of different soil supplements such as animal manure, sewage, fish, composts, seaweed, sand, bones, wood ashes, and probably many others in order to increase or maintain land output. Even Plato and Aristotle wrote about specific fertilization methods. Trying to figure out how to re-mineralize and revitalize soil has been among the goals of agriculture for over 10,000 years.

Since then, our technological abilities have increased dramatically. We have discovered and documented which plants need which minerals and elements to grow to optimum health. Through our understanding of the periodic table, we are able to pinpoint specific elements (e.g. manganese, copper, boron, etc.) that are important to plants in trace amounts. We have developed fertilizers to replace the major elements (macronutrients) plants need for basic growth – Nitrogen, Phosphorus, and Potassium (N-P-K).

Though we have been able to force plants to grow larger and faster, we may be missing a very important part of this equation. It is not simply “fertilizer in = growth out” as most people believe. While supplementing the major elements will allow plants to grow, they do so without the benefits of the trace minerals that often go un-supplemented. Many of these trace elements have been shown to help plants resist disease and provide superior nutrition. This leads to increasing inputs (fertilizer, insecticides, etc.) that put further strain on the soil and plants that depend on them.

As modern industrial farming increases the amount of plants grown per acre, so too does it increase the removal of minerals from the soil by the plants. Since we usually use these plants for food, we do not let them fall into the fields to decompose, as they would in nature. Without the natural cycle of dead plants re-mineralizing and supporting the microbial population of the soil, the burden falls to us applying synthetic fertilizers.

The problem with this approach is two-fold. The application of fertilizers to replace only the most used minerals in plant growth does not (usually) replace the trace minerals. This can lead to deficiencies that won’t kill the plants, but will make them more susceptible to disease and also may reduce nutrient content in our food. In addition, the lack of trace elements that allow the plants better resist pests or disease means that even more chemical inputs (pesticides) are used.

Each of these synthetic inputs can damage the natural balance of microbial and invertebrate life that creates fertile, healthy soil. Pesticides (and herbicides) have been shown to markedly reduce the concentration and population of soil-based microbes. In addition, recent findings have shown that the use of synthetic fertilizers has lead to a number of problems, from suppressing the activity of soil microbes to contributing to a dead zone in the Gulf of Mexico.

Soil erosion is a serious and increasing problem.
In addition, the tilling of soil also has an effect on nutrient retention and soil stability. Soil erosion is becoming a serious problem in many parts of the world. The Environmental Working Group (EWG) has a site up about this very serious problem.

While modern industrial farming has greatly increased yield at the expense of minerals in the soil, the modern organic farming movement is aiming to put some back. There are many different methods of trying to do this, but composting is one of the most widely used fertilization techniques used by organic farmers. Composting is essentially a controlled (and often accelerated) way of performing the natural decomposition cycle of organic matter. This returns not only the macronutrients (NPK), but also returns micronutrients that support a healthy soil biodiversity. Supporting a naturally bio-diverse soil means that fewer pesticides (if any) are needed.

The problem of soil depletion is one that affects almost every living thing on this planet. Without healthy soil, how can we have healthy plants? Without healthy plants, how will animals (including humans) get proper nutrition? Every animal depends, directly or indirectly, on the soil’s ability to produce nutrient rich plants as a fundamental link in the food chain. How long will we be able to sustain the planet without this crucial link?

Look for our follow ups to this post, where we will discuss the many different ways that we have found for re-mineralizing soil and the specific problems with pesticides.

-----
Resources:
Dirt! the Movie


-----
Researched and written by Dr. Rebecca Malamed, M.D. with assistance from Mr. Malcolm Potter.

No comments:

Post a Comment