As documented earlier, the growth of Chongming Island off the coast of Shanghai from three insignificant sandbars to China’s second-largest island in just several hundred years is further evidence of the power of agricultural runoff to permanently alter the landscape.
4. Allowance for Ecosystem Restoration
If a significant amount of farming were to take place inside the urban landscape, then the world’s ecological footprint of agriculture would become smaller. For most crops, about ten to twenty times the acreage it takes to raise them indoors could be converted back into hardwood forest outside. This is because crops can be grown year-round and none would be lost due to severe weather events. Large-scale environmental restoration is high on everyone’s list of things we wish we could do, but most perceive it as an unrealistic goal due to the amount of land we now need to farm, with more land needed in the near future as the human population continues to increase. The Food and Agriculture Organization laments in each edition of its State of Food Insecurity in the World reports that the simple solution to restoring the natural world is to leave it alone. One could seriously question this strategy of benign neglect, since the great majority of us now live either in cites or their suburbs and have never had the occasion to witness nature in a restorative mode. But be assured that there are numerous “proofs of concept” out there that convincingly demonstrate that the environment is much more resilient than we give it credit for. The dust bowl of the American Midwest returned to tall- and short-grass prairie just 20 years after most experts in land management had written it off as a desolate, sterile region never to recover. It’s no wonder they held this pessimistic view, when newsreel footage of that period shows toxic black clouds of topsoil about to engulf a whole town. Nonetheless, in the absence of any outside influence (i.e., farming), save for a few small restoration efforts on the part of the government, it quietly returned to its former ecological setting.
The entire northeastern portion of the United States was clear-cut at least three times in our history, and when it became apparent each time that farming could not succeed there, the land was abandoned and the trees obliged by returning in full force. An excellent example that has a solid scientific basis for describing what happens to a forest when it’s been clear-cut, then left alone, can be found in the online records of the Hubbard Brook Ecosystem Study (http://www.hubbardbrook.org/), whose ecological setting is in northern New Hampshire. A summary of the study’s initial results is instructive to those who remain skeptical that nature has the resources to recover from a catastrophic event like being clear-cut. When the study was initiated in 1967, an entire watershed’s worth of forest was cut down, but the trees were left in place. The quality of the water draining the watershed was continuously monitored for dissolved minerals and organic compounds before, during, and after clear-cutting. Three years later, the quality of the water in the streams had returned to preexperimental condition. The trees took longer to grow back. At first, pioneer plants—shrubs and bushes—dominated the landscape. These were shade intolerant, and due to the continuous exposure of their seeds to sunlight, they rapidly germinated and filled in the wide-open spaces left by the downed forest. The pioneer plants grew rapidly, creating shade. Their roots helped hold the soil in place until the trees could take over that function, allowing the draining streams to return to their original high quality. The tree seeds in the soil that were now shielded from direct sunlight by the shrubs and bushes were stimulated to germinate. When the saplings had grown above the level of the shrubs and bushes (about five years) creating shade once again, the pioneer plants (shade-intolerants) died off, giving way to the regenerated forest. Within twenty years, the mixed boreal forest of Hubbard Brook watershed was once again standing tall and proud, without a single person lifting so much as a finger to help the process along. The revealed secret to reforestation that arose out of that seminal long-term ecological study (which is still ongoing, by the way) is the realization that all the seeds for the shrubs, bushes, and trees were in the ground awaiting their marching orders. The moment a disaster hits, nature goes into overdrive and ramps up the repair mechanisms. It is an amazing process to witness, regardless of which ecosystem is at risk, and reflects the cumulative knowledge of millions of years’ worth of natural selection. In the end, nature always gets it right.
The demilitarized zone between North and South Korea, a ten-mile wide designated no-man’s-land stretching from coast to coast, was declared off-limits in 1953 following the signing of the truce agreement in that same year. It is currently a verdant, peaceful wildlife reserve completely devoid of human activity. Once again, nature hung out its no help wanted sign and proceeded to regenerate itself. In another example, in 1986 Chernobyl, Ukraine, was the site of the world’s worst nuclear power plant meltdown, resulting in huge amounts of radioactive fallout and contamination of the surrounding environment for miles in all directions. Amazingly, the wildlife did not obey the abundant no trespassing warning posters and slowly began to repopulate the region shortly after humans evacuated it. Today, it’s a haven for wildlife. Almost all of the animals and plant species that were forced out of the region by farmers have returned. That is not to say that it’s safe for humans to return to Chernobyl simply because it has the appearance of normalcy. The plants and animals are certainly paying a heavy price for their willingness to live in such a highly contaminated setting.
Costa Rica is a country rich in history that has enjoyed an unusually long period without internal strife. As a result, the landscape has filled up with farms, replacing the tropical rainforest with sugarcane, coffee, and forest plantations; a variety of short-cycle crops; and cattle. Despite heavy encroachment, approximately 47 percent of the country is still forested. It is understandable, then, that ecotourism has become a dominant player in that country’s economy, with the Bosque Lluvioso rain forest as a primary destination for those seeking total emersion into a pristine tropical cloud forest. From 2000 to 2005, the country’s cattle industry was forced to decrease in size due to the United States electing to buy cheaper livestock from other sources. This left large holdings of cleared land fallow. The Boyce Thompson Institute for Plant Research at Cornell University then began a restoration project that has resulted in the successful reforestation of a small portion of that damaged tropical environment, using state-of-the-art horticultural methods and seeds from local tree species. In addition, abandoned farmland in other parts of Costa Rica has also returned to its former ecological setting. According to a recent FAO report, State of the World’s Forests 2009: “In most Central American countries, net forest loss declined from 2000 to 2005 in comparison with the previous decade, with Costa Rica achieving a net increase in forest area.” Finally some good news about tropical forests!
Another restoration success story with more human input involved the recovery of a significant portion of the Samboja Lestari rain forest in the extreme eastern part of Borneo. In order to create a safe haven for more than one thousand baby orphan orangutans, Dr. Willie Smits, a wildlife biologist, through the help of local farmers, established a reserve by planting a series of native plants, including trees, on abandoned farmland. Before the plant life was restored, the farmland created by clearing forest had been parched and lifeless. In a short time, just three years after beginning the project, the pattern of weather returned to a tropical rain precipitation regime with daily episodes during the rainy season. The orangutans appear to be doing very well there, too.
Regrowth of forests provides several ecological services, the main one being sequestration of carbon in the form of cellulose, and the other restoration of biodiversity. However, how much carbon trees can remove from the atmosphere is somewhat controversial, and is still being investigated by a number of forestry researchers. It all seems to depend on what kind of trees (hardwood or conifer), how old and densely packed they are, and the latitude at which they are growing. One thing is certain, and that is that without trees, there would be few other eco
logical solutions for taking carbon dioxide out of the air. What’s more, no other damaged ecological setting can be encouraged to repair itself simply by leaving it alone. For example, coral reefs are composed almost entirely of calcium carbonate and are very efficient at sequestering carbon. Unfortunately, they are on the decline due to rising sea surface temperatures. At the same time, the oceans have become saturated with CO2, and instead of sequestering carbon at a higher and higher rate as atmospheric carbon dioxide continues to increase, the seawater is turning acidic as carbonic acid forms, leaving little else to help with balancing the atmospheric carbon budget.
So, for the sake of argument, let’s assume we could somehow convince the states of Ohio, Indiana, Illinois, and Iowa to convert all their agricultural land back into hardwood forest, which most of it was prior to 1600. If it were allowed to regrow, that much hardwood forest would consume annually around 10 percent of U.S. emissions of carbon dioxide as it reached maturity (thirty to forty years). Of course, without an option for growing crops in a nontraditional fashion (controlled-environment agriculture), we would never even begin to contemplate what the effects of reforestation of the American heartland might have on climate change.
5. No Use of Pesticides, Herbicides, or Fertilizers
The vertical farm will employ state-of-the-art hydroponic and aeroponic technologies configured inside a secure building. The design of the building will take into account the need for keeping out unwanted diners, such as insects and microbial pathogens, that in an outdoor setting are able to more than satisfy their nutritional needs and raise hell throughout the world’s agricultural landscape. The traditional farmer has to counteract this attack on crops with a variety of weapons, namely, pesticides and herbicides. In addition, fertilizers are essential for maximizing crop yields in nutrient-depleted soils. In contrast, the vertical farm will use pure water, into which a set of highly purified, carefully balanced nutrients will have been dissolved to satisfy the nutritional requirements of the plants. By adding additional nutrients that we also need, we will ensure that both the plants and the animals (us) will satisfy both parts of the equation. There will be no need to worry about contamination of our food with things like heavy metals, atrazine, diazinon, or human pathogens such as salmonella or E. coli 0157:H7. Enough has been already said about the adverse affects of these agrochemicals and contaminants on us and the environment without need for further exploration of this subject; suffice it to say that the data should convince any reader that it would be to our extreme advantage to avoid using them if we could. With the vertical-farm cultivation strategy, in which we have total control over everything, it would be possible to do so.
6. Use of 70–95 Percent Less Water
Today, traditional agriculture uses around 70 percent of all the available freshwater on earth, and in doing so pollutes it, rendering it unusable for those living downstream. In contrast, hydroponic, and more recently aeroponic agricultural technologies have revolutionized the way water is used to grow plants without the damaging side effects of agricultural runoff. When these two methods are employed in “closed loop,” or self-contained, systems, a huge amount of water is conserved, up to 95 percent in some extreme cases. These two methods of cultivation are the NASA and the European Space Agency’s answer for sustainable food production, and will enable astronauts to eventually produce food on the moon or Mars. Similarly, once vertical farming is perfected, food production on earth could take place anywhere. That is the long-term payoff behind the vertical farm project.
So how do these two related grow systems work? Contrary to popular belief, plants do not require soil, per se. What they use soil for is a solid base of operations into which they can spread their roots. In other words, the earth serves as a physical support system. That is why plants can be found all over the world, regardless of the kind of soil, as long as there is enough water and dissolved minerals, and a source of organic nitrogen. Provided the soil type does not adversely affect the plant by being too acidic or basic, then it’s possible to get plants to grow nearly anywhere on the planet, even in the cracks of sidewalks or on the cliffs of mountains as bonsai plants. Plants can even colonize newly formed volcanic islands that have no soil at all. In fact, plants actually help create soil there by breaking down the large, rocky substrate into smaller and smaller particles through the growth of their roots until it comes to resemble a kind of primitive soil.
Hydroponics, developed in 1937 by Dr. William Frederick Gericke at the University of California, Davis, is the method of choice used routinely by nurseries to get seeds to germinate and sprout roots before they are transplanted into some form of potting soil. The avocado seed is probably the most familiar example of a plant that can grow to near maturity from a seed in a glass of tap water, with nothing more added except fresh air and sunlight. The reason it can achieve such advanced growth characteristics is that it has huge amount of stored nutrients in the seed itself. All it really needs to sprout—grow a stem and leaves—is water. Kids (and adults, too) love to watch it grow from a pale, tan, wrinkled, lifeless object into a brilliant green plant that, when transplanted into a pot of soillike material, continues to grow and often produces avocados if watered regularly. It is one of those small “miracles of life” that parents love to introduce to their children. Avocados are no different from all other plants in that they give their seeds the maximum chance for survival by storing lots of goodies in them. All seedlings will produce adult plants that can carry on with maintaining the species, given a reasonable climate regime. Life indoors will ensure that a “reasonable” environment is always there.
The essential elements that plants need are colored orange in the periodic table, and include an organic source of nitrogen. We, on the other hand, require at least seven additional elements (colored orange). So, when we design diets for hydroponically grown crops, we need to include all of the essential ones in the nutrient solution that bathes their roots. This is where I imagine large agrochemical companies could convert from synthesizing pesticide and herbicide manufacturing and become the suppliers of ultrapure, chemically defined diets for crops grown in vertical farms. It wouldn’t take much in the way of economic incentives to convince that beleaguered industry to do the right thing and get on board the global green movement. After all, the executives and workers of those large corporations have families, too, and I am sure they all care about what happens to their own children and grandchildren over the course of the next fifty years.
Setting up a hydroponic facility is largely constrained by the kind of crop one wants to produce. The configuration is determined by the root system of the plant. The liquid portion of the operation is pumped slowly through a specially constructed pipe, usually made of a plastic such as polyvinyl chloride (or PVC), though it’s not a requirement that plastic be used. Bamboo in various diameters could also serve the purpose quite well, and since it’s one of the toughest natural materials we know of, bamboo would be ideally suited. Also, it’s very easy to grow. There is no need to lock into any technological niche to begin with, however. Once the piping is set up, nutrients are dissolved into the water phase and circulated through the piping, all the while being electronically monitored for concentrations of each element and organic nitrogen. The result is uniform plant growth under optimal conditions. For a list of major hydroponic growers and the extensive variety of crops they have commercialized, see the Appendix.
Aeroponics, invented by Richard Stoner in 1982, takes hydroponics and “kicks it up a notch.” Small nozzles located under the plants spray a nutrient-laden mist onto the roots, supplying them with everything they need. It is so conservative with respect to water use that it consumes about 70 percent less water than hydroponics, and will undoubtedly become a major player in the next phase of controlled-environment agriculture.
The question frequently arises: “Why don’t the greenhouse tomatoes I have to buy in the winter taste as good as the ones I can grow in my own backyard?” I think in the
“old days,” the indoor varieties indeed were not up to the standards of soil-grown tomatoes. The reason is that when it became possible to grow commercial levels of produce indoors, growers strove to make their crops appear to be flawless to the consumer. They got exactly that: the perfect-looking tomato. However, one bite proved that you can never judge a tomato by its outward appearance; it was mushy and tasteless. The essence of a good-tasting tomato is hard to beat and easy to recognize, so the greenhouse industry began to look into why theirs didn’t match up. By studying the outside conditions that produced tasty veggies (e.g., cold nights, warm days, or short periods of drought), they concluded that some stress was necessary in order to elicit flavonoids (complex organic molecules specific to plants). These molecules are the essence of why most vegetables have distinctive flavors and aromas. In addition, restricting the water a plant receives increases its sugar content, heightening the flavor even more. Today, many indoor growers have taken advantage of this information and now consistently produce the finest-tasting vegetables on the market. For example, EuroFresh Farms, located in Wilcox, Arizona, regularly wins blind-tasting competitions for its tomatoes. The greenhouse industries of the Netherlands and Mexico have also caught on to the new methods of how to produce tasty crops. Unfortunately, many small greenhouse operations still do not “get it.” It’s a constant tug-of-war between consumer and producer that will probably go on regardless of the fact that growers know what to do. For some, it’s just too involved to care much.
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