Barren Land

Desertification occurs when the productive potential of land falls by 10 percent or more. When this happens, nondesert areas become more like deserts, a biome in which water is not readily available to the biota and where evaporation rates exceed the precipitation rates. (Desertification does not cause true deserts, which are natural biomes.) Desertification ranges from moderate (10–20 percent drop in productivity) to extreme in which the land supports less than 50 percent of its former productivity and topsoil has been replaced largely by sandy soil.

Desertification caused by the drying conditions associated with climate change usually begins at the edge of land that is already fairly dry. Therefore, desertification expands into existing deserts and the outskirts of grasslands. Desertification caused by human activities occurs at a vulnerable spot and then creeps outward if the climate remains dry. For example, overgrazed ranchland can turn too dry to support grazing and the dry, barren land can spread into adjacent areas.

Forests do not turn into desert spontaneously, but climate change has contributed to a progression of some forest areas into dry barren land. Higher temperatures in the mountains and smaller snowpack melts have contributed to drought, drying of the land, and then severe wildfires. These fires are becoming more frequent as well as hotter and more dangerous as climate continues to change. Furthermore, some places in the United States have suppressed fires to protect homes built in the woods, but this only creates more burnable fuel should a fire strike. Fire, drought, or disease infestation—all events that increase with global warming—kill living things faster than they regrow. Craig Allen, a landscape ecologist in New Mexico, explained the matter for National Geographic in 2008: “This is a dilemma for the Park Service. The projections are that Joshua trees may not survive in Joshua Tree National Park. Sequoias may not survive in Sequoia National Park. What do you do? Do you irrigate these things? Or do you let a 2,000-year-old tree die?” Fire management decisions therefore have an impact on the rate of desertification in some places.

Desertification leads first to soil erosion, which then leads to poor crop production for food for animals and people. Poor crop cover causes more soil erosion, leading to a downward spiral of the land’s quality. In countries suffering severe water stress, the process leads to famine, economic losses, and poorer living conditions. The past few decades have seen a new type of nomad walk the Earth: environmental refugees. Environmental refugees are people forced to migrate from their homelands to find food and water in other places. At the same time, people living in drought may add to the dry conditions by drawing water from sources far away to irrigate the few crops they have left. Bodies of water eventually run dry and the drought worsens.

At its worst, desertification results in parched land with poor drainage that cannot retain moisture, so its water evaporates faster. The high evaporation rate leaves behind dried minerals. Salinization refers to the increased salt levels in evaporated soil; these salts are sometimes called white alkaline salts when they contain arsenic or zinc. Some dry lands in the western United States contain elevated levels of selenium, an element

» condensation—conversion of water vapor into droplets of liquid water

» precipitation—water that falls from the atmosphere to land or to surface waters as rain, snow, sleet, or hail

» infiltration—downward movement of liquid water through soil

» evaporation—conversion of liquid water into gas, or water vapor

» transpiration—movement of liquid water from plant roots, upward in vessels, and into the atmosphere from the leaves as water vapor

Forests serve in the water cycle in two critical ways: transpiration and water storage. Both animals and plants transpire water vapor into the air, but animals transpire as part of aerobic respiration when they exhale moisture from their lungs. Plants and trees possess special cells on the underside of their leaves, called guard cells, that release water vapor from the plant into the atmosphere. The transpiration process begins when warming problem seen today, but it is important to note that natural climate cycles also contribute to drying the land. Specific human influences, other than global warming, that contribute to desertification are the following:

» overgrazing and poor grazing management

» cultivation of sensitive dry lands already at risk of desertification

» deforestation

» intentional or accidental burning of vegetation from arid and semiarid areas

» incorrect irrigation leading to erosion, soil compaction, and salinization

Arid lands are true deserts where little precipitation ever occurs; semiarid lands are dry lands that receive small amounts of precipitation, approximately 10–20 inches (25–50 cm) per year.

Overgrazing has been a major cause of the increased rate of desertification in the past 40 years. For centuries semiarid rangelands supported cattle because herders moved their animals over large ranges to allow the grazed land and its grasses to recover. Early civilizations simply copied the natural grazing-migration behavior practiced by animal herds in North America, Africa, or Asia to this day. These animals followed the seasonal grasses and the pans that filled with water after a rainy season. (A pan is a shallow pool filled in the rainy season and dry in the dry season that supplies water to migrating wildlife.)

Modern grazing includes fencing animals into large but confined ranges. Windmills and irrigation systems supply water to rangelands so that herds do not need to migrate in search of water. Poorly planned wells and irrigation have added to the overall desertification process by pulling the last remaining amounts of water out of the ground. All of these activities have put regions of the world into water-stressed conditions.

Population density and poverty also force people to overwork their land. As mentioned, this process leads to poor crop cover, patchy dry areas, soil erosion, and then further drying. As an example, the Department of Conservation Biology at South Africa’s University of the Western Cape has reported that South Africa loses 330–440 tons (300–400 metric tons) of topsoil each year due to overgrazing and overcultivation. In 2007 a spokesperson for South Africa’s Department of Environmental Affairs explained to a United Nations conference on desertification, “Most of African communities live on agriculture-based economies, and survive by subsistence farming or productivity of marginal lands.” This spokesperson added that the entire problem cannot be placed at the feet of impoverished communities. “However, activities that take place in the developed economies can indirectly contribute to the livelihood of these distant communities due to the global impacts of climate change and desertification.” In short, poverty contributes to environment decay.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Forest Biotechnology

Forest biotechnology is a 50-year-old science that uses molecular biology to improve aspects of tree metabolism and wood and fiber production. Molecular biology is the science of isolating and studying genes that carry specific traits in living things. It often includes recombinant engineering in which a scientist transfers one or more desirable genes into a different tree species. Forest biotechnology therefore uses recombinant techniques for the purpose of bringing favorable attributes into a population of native trees.

In forest biotechnology, scientists can improve natural, native trees by following a series of steps that begin by selecting a tree with superior qualities. Examples of desirable qualities are disease resistance, drought tolerance, or resistance to climate change. A biologist isolates the desired genes from the superior tree’s deoxyribonucleic acid (DNA) and puts them into normal tree DNA. This gene transfer can take place either by crossbreeding the two types of trees or by putting the new genes into regular seeds by recombinant techniques. (Crossbreeding is the process of breeding two different types of individuals so the offspring contain traits from both parents.) After the first generation grows, the biologists again crossbreed the new type progeny with other superior progeny to produce a new generation of improved trees.

Forest biotechnology currently works in the following major areas: molecular details of wood formation; synthesis process of the fibers lignin, cellulose, and hemicellulose; pathology and disease resistance; plant hormones; and in vitro growth of tree tissue. Forest biotechnology has also turned to finding ways of affecting climate change. Future biotechnology projects may develop the following innovations: improved biofuels from
cellulose-derived ethanol; trees that capture and store more carbon; trees that withstand wider temperature ranges; forests that produce more wood in smaller areas; trees that resist invasive plants and pests; and trees that remove contaminants from the soil.

All of the focus areas in forest biotechnology aim to achieve one or more of three main objectives:

1. studying and improving tree genomes
2. creation of new biofuels
3. preservation of heritage trees

Heritage trees are trees of particular importance to a community because of their age, size, location, history, or ecological significance. Many U.S. cities identify anywhere from a few to hundreds of heritage trees that would be considered a terrible loss if they were cut down or killed by disease.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Ecoforestry

Ecological forestry, or ecoforestry, refers to sustainable practices that conserve
forests even as humans receive value from them. Ecoforestry can be thought of as equivalent to sustainable forestry.

For centuries people measured the value of forests in terms of the natural resources they provided: wood, paper, maple syrup, fruit, etc. Forests will undoubtedly continue to provide these things, but in order to assure a future for forests ecoforestry offers ways in which people can help forest ecology even while forests provide products. In order to sustain a forest so it can provide monetary (also called instrumental benefits) and aesthetic (or intrinsic) benefits, people must follow many of the sustainable techniques discussed in this chapter. For instance, sound fire management, selective tree harvesting, and protecting forests from encroachment play roles in ecoforestry. The following list summarizes the main aspects of ecoforestry:

» manage forests to conserve biodiversity, soil, and water

» consider nonwood products to replace wood products

» choose selective cutting over strip cutting and strip cutting over clear-cutting

» limit logging and road-building that fragments uncut forests

» avoid clear-cutting, seed-tree harvesting, and shelterwood harvesting on steeply sloped hillsides

» leave fallen and dead trees to provide habitat and to recycle nutrients

» buy only woods certified as grown in a sustainable manner

» choose natural regeneration over monoculture methods

» use low-impact cutting, harvesting, and yarding methods

The Forest Stewardship Council (FSC) administers a certification program that assures the public that wood or paper products have been produced by sustainable methods. Timber companies can apply for this certification by fulfilling the council’s requirements. During the certification process, council representatives inspect the path of a wood-derived product from the forest all the way to the final product, whether it is a sheet of paper, a cardboard box, or a plank of lumber. FSC-certified products bear a logo that informs the public whether a wood product comes from sustainable harvesting and manufacturing methods.

Ecoforestry also promotes new technologies in alternate wood products and new sciences for maintaining forest health. Forest biotechnology provides an example of a fast growing specialty within ecoforestry.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Legal Protections for Forests

Forests and grasslands in the United States, Puerto Rico, and the U.S. Virgin Islands receive legal protections from the federal government so that their land area will not be destroyed for industry or urban development. (Six states do not currently have a national forest or grassland: Connecticut, Delaware, Hawaii, Massachusetts, New Jersey, and Rhode Island.) These protections ensure that plant and animal life in these ecosystems
survive for generations, but also ensure that people can visit and enjoy these environments. The Forest Service of the U.S. Department of Agriculture (USDA) has the legal authority to manage the nation’s forests and grasslands. Currently the U.S. Forest Service’s authority covers 44 states plus Puerto Rico and the Virgin Islands, 155 national forests and 20 national grasslands, including 193 million acres (777,000 km2) and the following management categories:

» minerals, mining, rangeland, timber, wilderness, wildlife, and recreation management
» cultural resources
» water resources
» trails
» wild and scenic rivers
» fire service roads
» international forestry
» business administration

Laws alone cannot protect forests if government leaders or industries try to revise them in order to aid free commerce. For example, in 2006 the White House removed forest management from the NEPA so that forest officials would no longer be required to prepare environmental impact reports before changing forest management plans. As a consequence, management plans do not receive scientific review or public comment. A few years earlier, the federal government exempted the Tongass National Forest from the Roadless Rule. Both of these changes presumably give oil exploration, logging, and other industries easier access to forests.

Presidential adviser Karl Rove summarized the intent of weakening forest protections to National Review in 2007: “On energy, the environment, and climate change, he [President George W. Bush] is developing a new paradigm. Emphasizing technology, increased energy-efficiency partnerships, and resource diversification, his policies are improving energy security and slowing the growth of greenhouse gases without economy-breaking mandates and regulation.” Shortly before the changes to the NEPA went into effect, the Wilderness Society president Bill Meadows remarked, “It is a shame that this administration refuses to recognize that public participation in major decisions about projects like timber sales should not be feared and fought, but should be a welcome and helpful part of making informed and thorough decisions.” Almost every person holds a different vision of what should be done to protect the nation’s forests and also ensure the nation’s economic well-being.

One of this country’s first conservationists, John Muir, described the difficulty of finding common ground in managing forests: “God has cared for these trees, saved them from drought, disease, avalanches, and a thousand tempests and floods. But he cannot save them from fools.” The sidebar “John Muir” provides more insight on this environmentalist.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Forest Fire Management

Forest fires are caused by natural actions such as lightning strikes, or may result from human activities. In either case, good fire management and periodic natural forest fires help restore the vitality of forest ecosystems.

Three types of fires occur in forests: (1) surface fires that burn leaves, dense vegetation, and small immature trees; (2) ground fires fed by peat and decayed matter that spread to underground fuels; and (3) crown fires that burn up from the ground’s surface and travel across the treetops. Surface fires help ecosystems by clearing out constrictive dense shrubbery and leaf litter. Though these fires harm some immature trees, surface fires do not cause significant damage to mature trees, and they travel at a speed that allows wildlife to escape. Ground fires and crown fires present bigger problems. Ground fires smolder for weeks undetected and can suddenly flare into a potentially hazardous situation. Crown fires burn hot, fast, and uncontrolled, and in doing so they destroy trees, surface vegetation, habitat, and wildlife that do not escape. Crown fires have also caused the loss of homes and human lives in forested areas.

Fire management refers to the control of unexpected or planned fires for the purpose of improving the forest. By periodically burning dense growth, managed fires prevent the explosion of dangerous crown fires. Forest officials have two options on how best to manage fire. The first method involves what are called prescribed burns, in which ecologists set small, contained surface fires to thin out dense growth and so reduce the chances of crown fires. Fire crews surround the burn area to assure the flames do not escape and go from a controlled to an uncontrolled situation. The second strategy involves letting natural fires burn uncontrolled as they have for hundreds of years. These uncontrolled fires can seem cataclysmic in news reports, leading to disagreement on whether these fires are better or worse than prescribed fires. The New Mexico ecologist Craig Allen explained to Audubon magazine in 2001, “It’s not that Smokey was all wrong, but he sure as heck wasn’t all right either. Fire’s effects are variable, just as landscapes are variable.” Allen’s comment correctly points out that even the best fire management cannot predict how fires will behave with 100 percent accuracy.

Because prescribed fires and natural uncontrolled fires can behave in unexpected ways, good fire management also includes safety measures for houses and other buildings in the forest. Homeowners or work crews should clear all vegetation from a zone of about 200 feet (46 m) from the building. This helps prevent flames from approaching the structure. Safety zones in combination with firefighting have saved many buildings that were almost completely surrounded by fire.

Forest fire suppression that took place for decades in the United States—encouraged by the Smokey Bear campaign—may have hurt forest ecosystems. A community of organisms depends on fire to reestablish their populations. Though wildfires have been difficult to study, scientists have gathered the following facts on the effect of fire activity on forest biota:

» Some species appear only in postburn habitat.

» Certain conifers require intense heat to open cones and release seeds, a process called serotiny.

» Fire clears the ground for new seed germination.

» Some insects seek burned areas, gathering for mating and enhancing genetic diversity.

» Insect species use burned bark as nesting sites.

» Reptiles and amphibians escape fire by hiding in subsurface soils.

» Bats that roost in trees seem unaffected by the fire, and sometimes populations increase due to higher insect numbers.

» Elk, deer, and sheep numbers may decrease slightly; mountain lions and wolves generally escape fire.

The study of fire entails fire science, which covers topics such as how fires burn and travel through different types of trees (tropical versus deciduous, for example), the best use of fire retardants, and postfire rehabilitation techniques. Fire management also contains the following specialties: fire crew safety and clothing; firefighting techniques; fire road planning; aircraft firefighting; and development of new fire suppression chemicals.

In 2003 Congress passed the Healthy Forests Restoration Act, which allows timber companies to burn dense overgrowth in return for taking commercially valuable trees from forests. The companies need not open their plans for environmental review or public comment, which has raised the ire of environmental organizations. The Wilderness Society has stated that the act “poses a major threat to environmental protection and public involvement in federal land management. Furthermore, the bill does virtually nothing to protect homes and communities from wildfire.” On the contrary, President George W. Bush felt the bill represented “good, common-sense environmental policy. During seasonal droughts, these small trees act as ladders for fires to reach to the top of our oldest and tallest trees.” Much of the disagreement arises from the many unknowns regarding forest fires. Ecologist Allen put it simply, “This is a story we don’t know the answer to yet.” Like many aspects of natural resource management, fire management involves differing viewpoints and many questions for the future.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Silk from the sea - No sow's ear

A species of crustacean makes silk underwater

SPIDER silk is impressive stuff. Stronger than steel, flexible and exceedingly light. Barnacle glue is equally special. It holds an animal whose ancestors swam freely in the sea to rocks that are often battered by powerful waves. What, then, might a combination of the two achieve? Fritz Vollrath, of Oxford University, hopes to find out. As he describes in Naturwissenschaften, he and his colleagues have found that a small marine crustacean called Crassicorophium bonellii produces a material which has the adhesive characteristics of barnacle glue and the structural properties of spidersilk fibres. It is water-resistant and flexible, but also somewhat sticky, and is employed by the animals to construct tubular homes in the sediments of the sea bed.

Dr Vollrath's examination of Crassicorophium showed that the material is secreted by glands similar to those used by barnacles to make their cement. Given that Crassicorophium and barnacles are both crustaceans, albeit ones whose common ancestor lived 1oom years ago, that suggests a single origin for the ability to make this type of goo. Indeed, it might explain the mystery of how barnacles settled down in first place. Possibly, a Crassicorophium-like ancestor used the material to anchor itself to rocks and feed on passing titbits by catching them with its legs, as modern barnacles do. (The protective plates presumably came later.)

To examine the relationship between the newly discovered goo and barnacle glue, Dr Vollrath's colleagues, Katrin Kronenberger and Cedric Dicko, took a look at the chemical composition of both. The proteins of barnacle glue, they discovered, are dominated by amino acids called proline and isoleucine. These like to form cross-links between protein molecules, and thus tend to hold such molecules together. Crassicorophium goo, by contrast, is dominated by lysine, glycine and aspartic acid. These encourage protein molecules to stretch out and form fibres.

In addition, whereas barnacles just ooze out their cement, Crassicorophium processes its material in a spider-like spinning duct. The goo emerges from holes in the crustacean's legs and is spun into gossamer filaments by being stuck to a surface and then pulled out as threads. This way of spinning silk is remarkably similar to that used by spiders, which pull the material from their bodies using their legs. That similarity, though, is almost certainly the result of convergent evolution rather than a common origin, since the last joint ancestor of Crassicorophium and spiders lived way longer ago than the ancestor of Crassicorophium and barnacles.

Beyond its curiosity value, the discovery of Crassicorophium silk could have practical benefits. There is great interest, in biotechnological circles, in using silk more extensively as an industrial material. Its lightness, flexibility and strength would make it widely deployable. Adding Crassicorophium silk-or, at least, knowledge derived from its analysis-to the mix would extend that range. Dr Vollrath, for example, suggests that Crassicorophium silk's tolerance of salt water means it might find uses in medical applications where it would come into contact with salty bodily fluids. Thus, with luck, can curiosity-driven research of the most esoteric kind lead to good, solid human benefits.

Source of Information : [The Economist] Volume 401 Number 8760 Nov 19th - Nov 25th 2011

Chinese jewellers - Beijing bling

The world's largest jeweller goes public AT FIRST blush, Chow Tai Fook (CTF) 1""\.may seem to be in a spot of bother. The secretive Hong Kong-based chain of jewellery stores, which on some measures is the world's largest, has long wanted to float shares on the Hong Kong stock exchange. Alas, this week it was forced to scale back both the valuation and the size of its planned offering. Market rumours now suggest it will float about $3 billion-$4 billion-worth of shares next month.

That may be less lucrative than it hoped for, but do not shed any tears for Cheng Yutung, the firm's billionaire boss. The weakness of this deal (which would still rank as one of the bigger placements this year) has more to do with market turmoil than any specific snags confronting CTF. Though almost unknown in the West, the firm is a goliath, with a reported $4.5 billion in sales
last year, leaping ahead at a rate of over so% a year. It is already more than twice the size of Tiffany & Co, a posh American jeweller. A recent analysis by George Washington University and L2, a thinktank, found the brand is better known in China than Rolex, Bulgari or Tiffany. Considering the booming market in China, where most of the firm's 1,500 or so outlets are located, the future positively glisters for CTF. On some estimates, China's jewellery market is already a 250 billion yuan ($39 billion) business, growing at perhaps 15% a year. Part of the growth comes from the surge in wealth among the very richest.

The firm's real strength, however, lies in its ability to reach the rising middle classes who live outside the biggest cities and who are also splashing out to buy gems and gold (CTF can claim credit for getting mainland Chinese to embrace the more lucrative 24-carat variety). The World Gold Council reckons that China is the world's fastest-growing market for gold jewellery and the second-biggest after India. There are now signs that Chinese consumers, confronted with rising inflation, are buying gold as a hedge.

It is true that CTF has rivals, but it seems better positioned to conquer China. Luk Fook, for example, is another Hong Kong jeweller expanding rapidly on the mainland- but its strategy relies chiefly on using franchisees, whereas CTF ensures high quality and branding by directly controlling its far-flung outlets. Foreign firms are also expanding-Prada had a $2.5 billion stock placement in Hong Kong earlier this year, and Cartier has more than no bustling stores on the mainland-but they rarely stray outside the big cities.

Indeed, CTF could even profit by offering global rivals a distribution channel in remote regions. Local knowledge matters, for tastes differ widely: jade is popular in interior provinces, for example, while coastal regions prefer simple designs. CTF has just struck a deal with De Beers to market one of the diamond company's brands in its outlet in Changsha, the capital of Hunan province. Global markets may be punishing CTF today, but the heartland of China looks likely to reward its investors for years to come.

Source of Information : [The Economist] Volume 401 Number 8760 Nov 19th - Nov 25th 2011

A guide to goodness - Values for money

Want to know if a product is virtuous? There's an a pp for that
AS HE applied sunscreen to his young ./"\.daughter's face, Dara O'Rourke, a professor of environmental and labour policy at the University of California, Berkeley, found himself wondering if the lotion was safe. He realised there was no readily available answer. The result-two years, a team of chemists, lots of testing and a chunk of venture capital later-is GoodGuide.com. Launched in 2008, this is a website and smartphone a pp that rates 140,000 consumer products (currently only in America) according to their safety, environmental sustainability and the ethics of the firms that make them. Now Good Guide has created a new "purchase analyser" a pp designed to inform consumers not just about the values embedded in products, but also about whether they are the virtuous shoppers they say they want to be. Using the new a pp requires selecting a series of characteristics, which can range from whether the user favours organic products to buying only from firms with a good human-rights record. (It also rates how competitively things are priced, via a partnership with Price Grabber) The consumer then scans the bar code on a product with the camera in their smartphone. The a pp identifies it and checks in a database to score how it shapes up. Much therefore depends on the quality of the data, which Good Guide gathers from various sources, including government reports and scientific studies, and research by its own staff. If the product scores badly, the a pp will recommend an alternative item which is rated more highly. The a pp also tracks a consumer's purchases to see how well they fit with their selected values, giving a sort of personal virtue (or hypocrisy) rating. So far, Good Guide has mostly been used by shoppers who are already keen to know about any issues connected with products they buy. They are mothers concerned about a child's health, older people facing a chronic illness or supporters of a cause, such as animal rights. The hope behind the a pp is that the idea of finding out about a product's background will become mainstream. Consumers rarely change their buying habits, even when confronted with scientific and other data, says Mr O'Rourke. So he has drawn on insights from behavioural economics, which show shoppers can be greatly influenced by peer pressure and by information passed on to them by people they know. The a pp tries to take advantage of these pressures. The virtue rating will inform a consumer how well they are doing according to the values which they espouse. That measurement gives an incentive to do better. Soon, the rating will be able to be shared with others on social-media sites such as Facebook, which could inspire (or pressurise) a shopper to consume more thoughtfully. It might even, believes Mr O'Rourke, turn being a good shopper into an online game.

Source of Information : [The Economist] Volume 401 Number 8760 Nov 19th - Nov 25th 2011