Feeding the world
Feeding the world while nurturing the planet doesn't necessarily mean going back to nature.
The world's population continues to climb and, despite the rise of high-tech agriculture, 800 million people don't get enough to eat. Admittedly, this is often due to a lack of money, since the world actually produces enough for everyone. However, by 2050, we will have 9 billion mouths to feed, 3 billion more than today.
Agriculture must become the solution to environmental problems in 50 years. If we don't have systems that make the environment better — not just hold the fort — then we're in trouble,' says Kenneth Cassman, an agronomist at the University of Nebraska in America. That view was echoed by the Curry Report, a government panel that surveyed the future of farming in Britain.
Concerned consumers are facing what appears to be an ever-widening ideological divide. In one corner are the techno-optimists, who put their faith in genetically modified crops and improved agrochemicals. In the other are advocates of organic farming, who reject artificial chemicals and embrace back-to-nature techniques. Both sides cite plausible science to back their claims, leaving many people to believe we're faced with a stark choice between two mutually incompatible options.
Not so. If you set ideology aside and simply ask how the world can produce the food it needs with the least environmental cost, a new middle way opens. Like today's organic farming, the intelligent farming of the future should pay much more attention to the health of its soil and the ecosystem it is part of, as well as making shrewd and locally appropriate use of chemical fertilizers and pesticides. The most crucial ingredient in this new style of agriculture is not chemicals but information about what is happening in each field and how to respond.
Organic farming sounds attractive since an approach that rejects synthetic chemicals surely runs no risk of poisoning land and water, and its emphasis on natural ecosystems seems to be good for everyone. Perhaps these easy assumptions explain why sales of organic food across Europe are increasing by at least 50% a year. Going organic sounds idyllic, but it is also naïve and has its own suite of environmental costs, which can be worse than those of conventional farming, especially if it were to become the world norm.
Advocates of organic farming like to point out that fields organically managed can produce yields just as high as fields enhanced with synthetic fertilizers. For example, Bill Liebhardt at the Rodale Institute in Pennsylvania recently compiled the results of such comparisons for corn, wheat, soybeans, and tomatoes in the US and found that the organic fields averaged between 94 and 100 percent of the yields of nearby conventional crops.
But this optimistic picture tells only half the story. Organic farmers can't reach this yield every year if they want to build soil nutrients without synthetic fertilizers. They need to alternate with soil-building crops, and this is the biggest cost of organic farming. Vaclav Smil of the University of Manitoba in Winnipeg estimates that if farmers worldwide gave up the 80 million tonnes of synthetic fertilizer they now use each year, total grain production would fall by at least half. Either farms would have to double the amount of land they cultivate — at catastrophic cost to natural habitats — or billions of people would starve.
In short, the world needs chemical fertilizers, even though farmers in much of the temperate zone produce so much grain that they are hard-pressed to sell it at a profit. But if they were to cut back drastically on their fertilizer use and harvests were to shrink, grain prices would go up, making poor people hungrier. Besides the obvious moral cost of this approach, nothing destroys ecosystems more surely than hungry people who cannot afford to think about tomorrow because they are desperate to feed their children today.
Technologically advanced farmers can now monitor their yields and target their fertilizer to the parts of the field where it will do the most good, which, in turn, increases the yield. Eventually, farmers may incorporate long-term weather forecasts into their planning so they can cut back on fertilizer use when the weather is likely to make harvests poor anyway, says Ron Olson, an agronomist from Florida.
The challenge in moving towards a new, more intelligent farming of the future is as much political as it is technological. We already know how to build better soils, how to keep pests in check, and how to recognize when synthetic chemicals can provide the decisive edge to maximize yields. What's missing is political will. The time has come to step past the tired battle lines drawn up between organics advocates and agribusiness and enter the zone in between, where the real solutions lie.
How deserts are formed?
A A desert refers to a barren section of land, mainly in arid and semi-arid areas, where there is almost no precipitation, and the environment is hostile for any creature to inhabit. Deserts have been classified in a number of ways, generally combining total precipitation, how many days the rainfall occurs, temperature, humidity, and sometimes additional factors. In some places, deserts have clear boundaries marked by rivers, mountains or other landforms, while in other places, there are no clear-cut borders between desert and other landscape features.
B In arid areas where there is not any covering of vegetation protecting the land, sand and dust storms will frequently take place. This phenomenon often occurs along the desert margins instead of within the deserts, where there are already no finer materials left. When a steady wind starts to blow, fine particles on the open ground will begin vibrating. As the wind picks up, some of the particles are lifted into the air. When they fall onto the ground, they hit other particles which will then be jerked into the air in their turn, initiating a chain reaction.
C There has been a tremendous deal of publicity on how severe desertification can be, but the academic circle has never agreed on the causes of desertification. A common misunderstanding is that a shortage of precipitation causes the desertification — even the land in some barren areas will soon recover after the rain falls. In fact, more often than not, human activities are responsible for desertification. It might be true that the explosion in world population, especially in developing countries, is the primary cause of soil degradation and desertification. Since the population has become denser, the cultivation of crops has gone into progressively drier areas. It's especially possible for these regions to go through periods of severe drought, which explains why crop failures are common. The raising of most crops requires the natural vegetation cover to be removed first; when crop failures occur, extensive tracts of land are devoid of a plant cover and thus susceptible to wind and water erosion. All through the 1990s, dryland areas went through a population growth of 18.5 per cent, mostly in severely impoverished developing countries.
D Livestock farming in semi-arid areas accelerates the erosion of soil and becomes one of the reasons for advancing desertification. In such areas where the vegetation is dominated by grasses, the breeding of livestock is a major economic activity. Grasses are necessary for anchoring barren topsoil in a dryland area. When a specific field is used to graze an excessive herd, it will experience a loss in vegetation coverage, and the soil will be trampled as well as be pulverised, leaving the topsoil exposed to destructive erosion elements such as winds and unexpected thunderstorms. For centuries, nomads have grazed their flocks and herds to any place where pasture can be found, and oases have offered chances for a more settled way of living. For some nomads, wherever they move to, the desert follows.
E Trees are of great importance when it comes to maintaining topsoil and slowing down the wind speed. In many Asian countries, firewood is the chief fuel used for cooking and heating, which has caused uncontrolled clear-cutting of forests in dryland ecosystems. When too many trees are cut down, windstorms and dust storms tend to occur.
F What's worse, even political conflicts and wars can also contribute to desertification. To escape from the invading enemies, the refugees will move altogether into some of the most vulnerable ecosystems on the planet. They bring along their cultivation traditions, which might not be the right kind of practice for their new settlement.
G In the 20th century, one of the states of America had a large section of farmland that had turned into desert. Since then, actions have been enforced so that such a phenomenon of desertification will not happen again. To avoid the reoccurring of desertification, people shall find other livelihoods which do not rely on traditional land uses, are not as demanding on local land and natural resource, but can still generate viable income. Such livelihoods include but are not limited to dryland aquaculture for the raising of fish, crustaceans and industrial compounds derived from microalgae, greenhouse agriculture, and activities that are related to tourism. Another way to prevent the reoccurring of desertification is bringing about economic prospects in the city centres of drylands and places outside drylands. Changing the general economic and institutional structures that generate new chances for people to support themselves would alleviate the current pressures accompanying the desertification processes.
H In nowadays society, new technologies are serving as a method to resolve the problems brought by desertification. Satellites have been utilised to investigate the influence that people and livestock have on our planet Earth. Nevertheless, it doesn't mean that alternative technologies are not needed to help with the problems and process of desertification.
Blind to Change
How much of the world around you do you really see?
Picture the following and prepare to be amazed. You're walking across a college campus when a stranger asks you for directions. While you're talking to him, two men pass between you carrying a wooden door. You feel a moment's irritation, but you carry on describing the route. When you've finished, you're told you've just taken part in a psychology experiment. 'Did you notice anything after the two men passed with the door?' the stranger asks. 'No,' you reply uneasily. He explains that the man who initially approached you walked off behind the door leaving him in his place. The first man now rejoins you. Comparing them, you notice that they are of different height and build and are dressed very differently.
Daniel Simons of Harvard University found that 50% of participants missed the substitution because of what is called 'change blindness'. When considered with a large number of recent experimental results, this phenomenon suggests we 'see' far less than we think we do. Rather than logging every detail of the visual scene, says Simons, we are actually highly selective. Our impression of seeing everything is just that. In fact, we extract a few details and rely on memory, or even our imagination, for the rest.
Until recently, researchers thought that seeing involved making pictures in the brain. By building detailed internal representations of the world, and comparing them over time, we could spot any changes. Then in Consciousness Explained, the philosopher Daniel Dennett claimed that our brains hold only a few salient details about the world — and that is why we are able to operate successfully. This phenomenon, known as 'change blindness', demonstrates that we don't actually see as much of the world as we believe. While it might seem that our eyes capture every detail of a scene, our brains often only register a fraction of it, relying heavily on memory and inference to fill in the gaps. This selective attention has broader implications than we might expect, extending into many aspects of our daily lives.
Consider the simple act of driving. How many times have you missed a traffic signal change because your attention was momentarily diverted? This is not just a matter of distraction but a failure of our visual system to detect changes that do not seem immediately relevant. Researchers have even demonstrated that people can miss significant alterations in visual scenes, such as the appearance or disappearance of large objects, especially when their attention is focused elsewhere. One famous experiment involved showing participants a video of a basketball game. They were instructed to count the number of passes made by one team. In the middle of the game, a man in a gorilla suit walked through the scene, yet many participants failed to notice him. This experiment highlights how attention can be so narrowly focused on a specific task that we become blind to other, seemingly obvious, changes around us.
Simons' work on change blindness reveals how our brain constructs a coherent reality out of fragments. The brain's ability to focus on what's deemed important at the time can lead to significant gaps in our perception. We may believe that we are aware of everything happening around us, but in reality, we only see what we need to see at that moment.
The implications of change blindness extend beyond simple experiments. In real-world situations, such as witnessing a crime or driving, our selective attention can have serious consequences. Eyewitness testimonies, for instance, may be unreliable because individuals often do not register all the details of an event, especially if their attention was focused elsewhere. This raises important questions about how much we can trust our perceptions and memories. Psychologist Christopher Chabris, who worked with Simons on the gorilla experiment, argues that understanding the limitations of our perception can help us better understand how the brain works. Rather than assuming that we see the world as it is, we must recognize that our experience of reality is shaped by our expectations, prior knowledge, and the limited capacity of our visual system.
The phenomenon of change blindness underscores the complexity of human perception. Our brains, while powerful, are not perfect recording devices. They prioritize information, often missing or altering details in the process. This selective attention allows us to function in a complex world but also leaves us vulnerable to mistakes and misinterpretations. As we continue to explore the intricacies of perception, it becomes increasingly clear that what we see is not always what is there.
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