Can the Forests Be Saved?
“MANY strokes overthrow the tallest oaks.” So wrote the 16th-century English author John Lyly. Words all too prophetic of the Federal Republic of Germany, where the number of ailing German oaks continues to grow. Of course, this is not the first time that trees have become diseased and have died. Still, forests have managed to survive for centuries. So why the excitement?
Characteristically, forest diseases attack only one particular species. But this time every major species of tree in Central Europe is involved. Never before has Waldsterben occurred in so many places at the same time or spread with such rapidity. Never before has the intensity of damage been so great, trees being struck indiscriminately, whether growing in poor soil or in rich, in alkali soil or in acid, at low elevation or at high.
Moreover, in former times the causes were easily determined—a drought, an insect plague, a fungus. Or if polluted air from a nearby industrial plant was to blame, the specific poisonous substance at fault was readily detectable. So when forestry officials saw the first evidence of disease at the end of the 1970’s, these “normal” causes were obviously suspect. But then they saw the disease move out to embrace more and more species: silver firs; then spruce and pine; later beech, oak, maple, and ash. With alarm they took note of an increasing number of trees stunted in growth, trees with defective root systems, trees with leaves or needles that tended to turn yellow and fall off. These and other heretofore unfamiliar symptoms proved that they were dealing with a new phenomenon. Who was the culprit killing their forests? They soon felt they had found it: acid rain.
The Role of Acid Rain
Sulfur dioxide and nitrogen oxides are produced by electrical generating plants, industrial boilers, and motor vehicles. Acid rain is formed when these gases interact with vapor to form dilute solutions of sulfuric and nitric acid. These noxious substances can be transported over long distances, even across international boundaries.
Canada, for example, claims that the high-sulfur emissions from power plants in the United States are largely responsible for the acid rain that is devastating its forests and waterways. In Europe a similar situation exists, wherein acid rain, perhaps originating in Central Europe, has played havoc with the lakes and rivers of Scandinavia, increasing their acidity and killing the fish.
When acid rain is absorbed into the ground, it breaks down natural minerals, such as calcium, potassium, and aluminum, and carries them into the substrata, thus robbing trees and plants of a vital source of nutrients. But further research has shown that this is not the sole reason for today’s Waldsterben. Trying to pinpoint the exact cause, however, has been frustrating.
The Unsolved Riddle
One meteorologist admitted: “We’re like a lot of blind men grabbing at an elephant.” Indeed, a Swedish forestry expert recently listed 167 theories that have been advanced to explain what is causing the problem.
Whatever the reason, “imported sulfur dioxide has partially been exonerated,” explains the U.S. magazine Smithsonian, “at least in the Black Forest.” This is because there is less sulfur dioxide in the atmosphere now than there was 15 years ago, and as Smithsonian notes, it “is lowest of all where trees are sickest.”
Research now would seem to indicate that traces of toxic metals that are emitted into the atmosphere by fossil-fuel-burning plants and vehicle exhaust fumes combine with acid rain to destroy nutrients necessary to keep trees alive. Some authorities believe that because of continuing soil acidification, trace elements may be dissolved and absorbed by the roots and choke off a tree’s water supply.
Hans Mohr, a Freiburg University teacher, claims that the difficulty seems to be created by nitrogen, the very substance plants often have a shortage of. He refers to research indicating that nitrogen compounds in the atmosphere have increased by 50 percent over the past 20 years. This increase is due mainly to vehicle exhaust; static emission; gas-, oil-, and coal-fired central heating; and ammonia emission by agriculture and refuse-disposal facilities. Bernhard Ulrich of the University of Göttingen argues that the trees are not being strangled by what is in the air but are being poisoned by what is in the soil. Other authorities point an accusing finger at ozone levels, at the sinking water level, or at ineffective forestry policies.
“A new avenue of research,” observes Smithsonian magazine, “contends that the guilt falls on no single air pollutant, but rather on an as-yet unknown interaction among them, so that the whole impact is greater than the parts.” This is very possible. Almost 3,000 chemical compounds exist that can be called air pollutants. For several decades they have been building up in concentration, subjecting the forests to continuous stress.
As long as the ecological system was intact and strong enough to reject the effects of pollution, all went well. But now when causes for sickness, such as frost, drought, and insects, make their appearance, the trees find themselves too weak to resist.
Obviously, many factors are involved in the overthrow of Germany’s proud oaks. Determining just which particular pollutant is chiefly responsible for their demise is as difficult and as pointless as saying which of ten water faucets being used to fill a tank is the faucet that finally causes the tank to overflow.
What Is Being Done?
Realizing that something must be done fast if the worst is to be avoided, local, state, and federal governments are resorting to “short-term solutions to maintain the trees until a longtime answer can be found,” as one magazine expressed it. Meanwhile, extensive studies are being made, including taking infrared pictures of the forests from the air to determine the extent of damage and what should be done.
‘Why don’t they just plant new trees to replace the diseased ones?’ you may ask. But it is not that simple, for newly planted trees are already beginning to show the same symptoms of disease as older trees. Even the use of fertilizers that counteract soil deficiencies has met with only limited success.
Top priority is being given efforts to lessen air pollution. Laws regulating industry have been tightened, and in the Federal Republic of Germany it is hoped that by the mid-1990’s these regulations will reduce the amount of sulfur dioxide by about two thirds and nitrogen oxide by about half.
Generous tax breaks have been given persons willing to buy cars equipped with devices, such as catalytic converters, that greatly reduce air pollutants. As an added incentive, unleaded gasoline has often been priced lower than leaded. In Austria, in contrast with most other European countries, unleaded gasoline is readily available everywhere. In Switzerland, at the end of 1986, new emission-control laws were put into effect, designed also to promote the sale of cars with catalytic converters.
These efforts are being made because, as the director of the Institute for Forestry at the University of Soil Cultivation in Vienna claims, Waldsterben can only be stopped if air pollution can be reduced to the levels of 1950. But is this realistic when the number of motor vehicles in Germany alone, with more cars per square mile than any other nation in the world, is over 19 times what it was at that time?
Tests show that the imposing of speed limits would reduce polluting emissions considerably. Yet this suggestion has run into stiff opposition. Some drivers, however, even in the celebrated racetrack atmosphere of Germany, are beginning to realize that for the sake of their forests—not to speak of their lives—they must slow down. Others, of course, selfishly reject any such restrictions. Typical of these are the drivers who display the bumper sign “My car will run even without the forest.”
Thus, a major factor in solving the problem is convincing individuals and governments to cooperate. Since air pollution ignores national borders, international policies are called for. Up to now attempts to carve out a unified program within the European Community have led to disappointment.
Can More Be Done?
Many people feel that more must be done. In fact, this feeling has helped give rise to a new political party in Germany called the Greens. Strongly dedicated to protecting the environment, this party achieved local and regional recognition during the late 1970’s. Finally, in 1983 it moved into the German Parliament, electing 27 representatives and attracting 5.6 percent of the popular vote.
A German expression claims that green is the color of hope. But do the Greens offer hope for the forests? Despite good intentions and idealistic goals, the party has made little headway. Many citizens consider them politically naive, offering simplistic solutions to complex problems.
Yet, many are taking practical steps to cut down on air pollution to the extent reasonably possible. They are driving slower, traveling less, joining car pools, using unleaded gasoline, and obeying antipollution regulations laid down by the government. But apparently this is still not enough.
The alternative of drastically curtailing the use of motor vehicles, airplanes, and industrial plants, while helping to solve the problem of air pollution, would most assuredly create new problems. Actually, the solution to Waldsterben—in fact, to all environmental problems—is to be found elsewhere.
[Blurb on page 8]
A major factor in solving the problem is convincing individuals and governments to cooperate
[Picture on page 7]
Scientists are divided on precisely how pollutants cause forest death