Название: Like a Tree
Автор: Jean Shinoda Bolen
Издательство: Ingram
Жанр: Биология
isbn: 9781609255114
isbn:
Two Kinds of Trees
My tree was a conifer (conifer means “cone-bearing”), in the tree family lineage that began 290 million years ago. Conifers are familiar trees, known to us as firs, spruces, pines, cedars, redwoods, cypress, podocarps, yews, and junipers. They originated in and continue to survive in poor soil, with extremes of weather from tropical to desert, to almost arctic. Among the conifers in California are coast redwoods, the tallest trees in the world, and the bristlecone pines, which are the oldest. They comprise the vast boreal forests in Alaska, Canada, Scandinavia, Russia, and Siberia. They thrive in places where conditions are difficult, including in areas where fires are common. They are survivors and pioneers—trees that move into devastated areas and grow where other trees do not.
The conifers are one of the two large tree categories that make up 99 percent of all trees: trees without flowers (conifers) and trees with flowers (the angiosperms). Angiosperms differ from conifers in their sexuality. The female ovule is completely enclosed within the ovary, and the male gamete must be carried to it via pollen tubes. Uniquely, angiosperms practice double fertilization. This is a very brief summation; left out are definitions and explanations, the various means of union and procreation, and how this contrasts with conifers. Suffice it to note that the obstetrics and gynecology of the two categories differ. The angiosperms are a huge universe of flowering plants (300,000 species), among which there are trees. The surmise is that flowering trees with woody trunks evolved from flowering plants, with missing links. Also not known are when, where, and how angiosperms originated.
Broadleaf trees are angiosperms: they include acacia, maple, elder, baobab, alder, aralia, birch, hickory, hawthorn, laurel, eucalyptus (gum), linden, olive, beech, banyan, fig, sycamore, ash, locust, mulberry, plane, coffee, holly, poplar, aspen, oak, willow, pepper, elm, and many others. Fruit trees, nut-bearing trees, and flowering trees are also angiosperms. There are about fifty times more species of flowering trees than of conifers. They usually grow where the soil is good or adequate, in temperate zones where the weather has predictable seasons, or in the vast tropical forests of the Amazon, central Africa, or Indonesia.
Tropical Rain Forests and Boreal Rain Forests
Both tropical rain forests and boreal forests are being destroyed at an alarming rate by humans for economic reasons. In an article in National Geographic (Wallace, “Last of the Amazon,” January 2007), Scott Wallace began with the sentence: “In the time it takes to read this article, an area of Brazil's rain forest larger than 200 football fields will have been destroyed.” Industrial-scale soybean producers are joining loggers and cattle ranchers in the land grab. Roads are cut through the forest to make valuable hardwood trees more accessible and transportable. In the Amazon, there are more than 105,000 miles of these roads, almost all made illegally, which then are used by squatters, farmers, and ranchers who clear the land by burning off the underbrush and trees that remain.
As indigenous people intuitively grasp, the benefits the Amazon provides are of incalculable worth: water cycling (the forest produces not only half its own rainfall, but also much of the rain south of the Amazon and east of the Andes), carbon sequestering (by holding and absorbing carbon dioxide, the forest mitigates global warming and cleanses the atmosphere), and maintenance of an unmatched panoply of life. But there haven't been profits in keeping the forest. Money is made by logging and by cutting it down for grazing and farming, not by leaving it standing.
Twenty percent or more of the Amazon rain forest has been cut down so far. When another 20 percent is destroyed, scientific expectations are that the forest's ecology will unravel. This would reduce the amount of rainfall that the forest produces through the moisture the trees release into the atmosphere. To this, add global warming: remaining trees then dry out, leading to droughts and susceptibility to fire. Amazon forest fires burned unchecked for months during the record drought of 2005–2006, followed in 2007 by the worst rain-forest fire in history. Smoke releases tons of carbon dioxide and other pollutants into the air, directly raising the ambient temperature, and further contributing to global warming by the production of more greenhouse gases. The deforestation story is the same in Indonesia, the country with the largest tropical forest in Southeast Asia, which replenishes fresh water and has a key role in weather and climate.
Whether my concern is about one tree or forests, one person or humanity, I learn what I need in order to grasp a situation that affects a species or a class of people (children, women, race, or religion) by paying attention to an individual that is representative. I want to see the forest and the trees, a metaphor that became literal. I learned from my Monterey pine that pine needles condense fog into lots of dripping water. Next I learned from others that trees also send water upward from groundwater; they transpire it from roots through leaves. Colin Tudge wrote that a big tree can transpire 500 liters (528 quarts) in a day.
In Tree: A Life Story, David Suzuki and Wayne Grady explained how one tree adds to the big picture: “A single tree in the Amazon rain forest lifts hundreds of liters of water every day. The rain forest behaves like a green ocean, transpiring water that rains upward, as though gravity were reversed. These transpired mists then flow across the continent in great rivers of vapor. The water condenses, falls as rain, and is pulled back up again through the trees. It rises and falls on its westward migration an average of six times before finally hitting the physical barrier of the Andes mountains and flowing back across the continent as the mightiest river of Earth” (2004, p. 68). This particular description captured my imagination and thereby my understanding.
The North American continent has its own vast, endangered boreal forests of conifers. In the waiting room of my optometrist, I picked up a six-month-old copy of Audubon just after I decided to write Like a Tree. In it, journalist T. Edward Pickens described Canada's boreal forest as “an emerald halo of woodlands, wetlands, and rivers that mantles North America. This is the greatest wilderness on the continent, a 1.3 billion-acre forest stretching from Newfoundland all the way to the Yukon. The Canadian boreal holds a quarter of the world's forests and most of its unfrozen freshwater, and sequesters 1.3 trillion metric tons of carbon” (“Paper Chase,” January–February 2009). More than three hundred species of birds breed there, and as many as five billion individual birds fly south from the boreal each autumn. These trees are being clear-cut to make paper, for books, catalogs, paper towels, and toilet paper. There are clear-cut areas measured in square miles. In an issue of National Geographic (June 2002), I learned that boreal forests have more wetlands than anywhere else in the world. Those in Russia and Canada each contain an estimated one million to two million lakes and ponds.
Saving Rain Forests: Greenpeace's Successes
The conifers are the trees I have most bonded with, and there is a geographic affinity between California and the North American boreal conifer forests that draws me to their plight. How many pine trees are cut down is a market supply and demand decision. Whether it is done with consideration for watersheds, habitats for wildlife, or generations to come (indigenous North American tribal wisdom considered the effect of their actions on the next seven generations) is a corporate decision made by people, who do so either because they are wise or to ward off negative publicity, which would be bad for business.
Greenpeace waged a successful five-year “Kleercut” campaign to demand that Kimberly-Clark, the company that makes Kleenex, Scott, and Cottonelle paper products stop destroying ancient boreal forest СКАЧАТЬ