Thursday, October 10, 2013

Adjusting the Earth

Today we're going to examine a subject a little more down to earth.

We truly don't appreciate just how much creatures adjust the environment around them to suit the microbes they need.

Trees are an excellent example of this. All plants, for that matter. Every plant has a community of fungi and microbes it needs around its roots in order to help take up the nutrients it requires for survival and growth.

Disruptions to this community can spell the death of the plant; and in plant monocultures, such as those propagated by modern agriculture—where we actually encourage a complete lack of species diversity— we are creating a situation wide-open to problems.

But let's get back to the trees, which are the subject of today's post. Every tree has a very specific microbial need around its roots; and the nutrients that the tree's leaves deliver when they fall are exactly the right blend of chemicals and are at exactly the right acidity for that particular tree.  (This may seem like a minor matter, but small changes in pH can lead to large changes in microbiology.) This means that the leaves, when they fall, are creating the best possible conditions to nurture their tree's future growth. They're also finely tuned to create conditions that do not favor the growth of hostile species; so trees and other plants condition the soils around them to lower the chances of competition. This is equally true in forests, prairies, and even marshlands. 

You might think that if you take those leaves away and put other leaves from a different tree (or some other composting material)  in their place, it will have the same effect, but that's not exactly the case. When you take the leaves away from the tree, over the long term, you're depriving it of the specific micro-environment it needs, a finely tuned set of relationships which evolved over millions of years, and substituting another, much less beneficial one.

It may not seem this way when you rake leaves up and move them, but the habit of moving litter away from its natural environment is contributing to long-term degradation of soil microbial communities all over the world, wherever it's practiced. While it doesn't kill plant and tree populations right away, it places them under constant low grade, long-term stress, and it steadily degrades the soils in which the trees are growing. 

Soils build far more slowly than we deplete them; and the majority of human activity is soil-destroying and soil-depleting activity. Real estate development creates so much soil disruption in a single year worldwide that nature would require thousands of years to create new soils to repair the damage. We can get away with such nonsense for only just so long before it catches up with us. Many of the areas being developed are the ones with the best soils; which means that agriculture is gradually being pushed out to the margins of habitable landscapes, where it is more tenuous and requires a much greater investment in energy, time, and resources to cultivate. These marginal landscapes are, furthermore, microbially impoverished, compounding the problem.

While one can counteract the various soil deficits we create by artificially boosting plant yields using fertilizers, this practice is something like using cocaine to stimulate yourself and stay awake. It works really well, but for only just so long; eventually, a dependency arises, and the results are, in the long-term, disastrous. The tremendous proliferation of corporations who sell chemical products -fertilizers, herbicides and insecticides- to dump on lawns by the millions of tons per year are not helping any; the general public, poorly educated on soil conservation at best, is aggressively marketed with disinformation which tells them to amend their homeowner soils using clumsy, unsustainable, but—for the corporations—very "profitable" methods.

Like the overuse of antibiotics, which is breeding whole new generations of disease-causing but drug-resistant bacteria, the widespread effects of poor agricultural practices are causing long-term, hidden changes to the way that the microbes around us are supporting what grows in our soil. We can't see it, so we don't worry about it; but we should.

The artificially created environments in which most cultivated and suburban plants are growing is inherently unsustainable without the support of artificial means; and it's likely that it will take centuries for the long-term implications of the impoverishment of our microbial environment to become apparent. It's quite possible that in many places, we will discover soils have been rendered essentially sterile because of the lack of the correct long term microbalance.

Even worse, because we have so few people interested in studying this right now, we are unlikely to identify and analyze the microbial communities around plants to any degree of the depth necessary in order to know how to preserve them.

By the time the things we need to know are evident, they may well be gone.

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