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A wake-up call on global warming

Renewable energies – and trees – are critical to reducing greenhouse gases. But manmade, single-species forests fail at carbon capture and adversely affect biodiversity, writes Feng Yongfeng.

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Many people are put off openly adopting a strategy regarding climate change, giving reasons such as “There’s no evidence for it”, or “I haven’t felt a change in climate”, or “It’s just a small scale problem”. A report recently issued by the US National Academy of Sciences shows how far out of step such people are. It finds that climate change is now a leading topic of discussion among the world’s scientists. From universities to environmental NGOs, anyone who has the least connection with this problem is seriously worried.

Former Vice President Al Gore recently travelled across the United States giving a series of speeches in which he called the public’s attention to the extremely urgent danger of climate change, and the damage that it has, in fact, already caused. His presentation was prepared for him, very meticulously, by a think-tank, for which Gore serves as a leader with strong confidence in science and technology. Closely focussing on and promoting the notion of the “digital planet”, he consistently extolled science and technology as forces that lead global trends. Yet the current spread of global warming, and responses to it, were firmly on his agenda.

When scientists target deforestation, increases in carbon-dioxide emissions and flows of methane into the atmosphere, they are perhaps neglecting a further factor in global warming, namely heat pollution. Our extensive use of crude oil and coal not only releases large amounts of poisonous and harmful gases into the atmosphere, but also something invisible: heat.

Heat is emitted from factory chimneys, from the refining of calcium carbide and from car exhausts; by these means, heat is clearly being added to the air around us. This increases the heat-island effect in cities, and -- due to population growth, rural-to-urban migration and urban conglomeration -- certain of the world’s urban regions are now becoming ever-larger heat islands. Thus a quantitative change becomes a fundamental change. The world is quietly transforming because combustion is not only releasing dangerous gases but also transferring heat into the atmosphere. The snowy summits of the Alps are under threat, whether by the large number of visitors scaling the mountains or by the heat issuing from cities.

Controversy over energy reforms

China has signed the Kyoto protocol, but in reality there are still all sorts of problems. China rapidly passed a renewable energy law that went into effect on 1 January 2006. However, there are controversies over some of the clauses in this law and over its implementation. Everyone, in fact, believes that the law is inadequate when measured against the hopes of professionals in the renewable energy field. It contains “hidden rules”, such as a clause on “protecting industrial growth”, which could slow down the development of renewable energy. Wind power, for example, is priced on the network at an only moderately profitable level; so, relatively speaking, it is not as lucrative as conventionally generated electricity. Hence the profit motive is compromised.

A large number of wind-energy enterprises face great risks in their first stages of development. The production of energy is accompanied by financial loss and disappointment, and this can lead within such companies to the misappropriation of investment funds and many other irregularities. State-produced wind-energy operations are not adequately supported, and consumers who wish to purchase green energy are not able to do so. All of these problems can adversely affect the momentum of renewable-energy development.

What we call renewable energy in fact includes more than one category. We can group together wind power, small-scale hydroelectricity and solar power, because these rely on natural phenomena and methods of production. There are many ways of exploiting these types of energy, yet China currently makes very limited use of them. For example, while solar power can heat water, the furthest this goes in China is in heating small amounts of water for baths and showers. No “household hot-water centres” have been built, and solar heating systems are restricted to individual households. Systems for whole buildings or communities have yet to appear.

Solar heat can be used to generate electricity, but solar electricity generation in China is almost non-existent. In fact there are many important ways of collecting and storing solar heat, or transforming it directly into other kinds of energy. One example, popularised in Scotland, is “Lochinver-Achiltibuie Road Solar Energy”. This was inspired by the fondness of sheep for enjoying warmth from the surface of roads (as observed by a Dutchman, Henk Verweijmeren, when travelling between Lochinver and Achiltibuie on the west coast of Scotland). If water pipes are installed in the roadbed, the heat can be transferred into the water.

There are all kinds of uses for this technology. But China’s technicians are evidently still stuck in the “copying” stage, and do not dare to innovate. They cannot develop forward-thinking plans, but rather just imitate the actions of others. The generation of electricity from solar energy depends greatly on the use of new materials, yet China’s research and manufacture of new materials has seen very few breakthroughs. China mainly buys technology and production facilities from other countries to carry out simple processing and construction.

Because the need for investment is enormous and the demands on technicians’ knowledge and skills are so high, even with traditional silicon-based technology, China’s enterprises lose their nerve and do not move forward. Many well-known companies do work with advanced technology – but only as “processing factories”. The technology, the production facilities and the raw materials are all bought from other countries, and the products may even be sold to other countries.

Physicists agree that renewable energy in China is in a poor and dissipated state. For this reason, a final way out of our energy problems is controlled nuclear fusion. Here “control” clearly has two meanings. One is the control that must be exercised in progressing nuclear technology: it requires slow and orderly development, so that under human guidance it may release its power, helping us to solve the energy predicament we currently face. The second is the control of access to nuclear technology. Because of its highly dangerous nature, there is a need to restrict this technology to reliable countries and reliable people under reliable systems. Otherwise we will not get the best from it. Each new kind of technology brings with it new responsibilities that have to be faced, and sometimes we do not know what it is that we have to be afraid of.

The importance of trees

We should be planting trees in large numbers, but instead we are cutting them down

Within “carbon capturing technology” or “carbon sequestration technology”, which aims to replace carbon dioxide in the soil, ecological systems provide by far the best results, and a great many scientists are now striving to achieve more in this area. There are simple formulas for working out the carbon-storing power of different types of trees, of different ages, in different environments. These can also help scientists to determine the contribution of ancient natural forests to carbon-storing capacities within each type of climate belt.

However, the terrible situation that our planet now finds itself in is that just when we need more trees, they are being cut down in great numbers. Just when we need natural forests, these are being exchanged for manmade forests, albeit planted in the name of “afforestation”. Just when we need ancient forests or forests with a long lifespan, these are being exchanged for annual plants. Compared to ideal carbon-storing capacities that we need, the capacities of such annual species are negligible.

As well as capturing carbon, forests also function to maintain climates and reduce temperatures. When we talk about the mirror-like action of snow-topped mountains in reflecting energy back into space, it is easy to conceive of the absorbing and transforming effect of forests on the sun’s energy. This effect is, if anything, more exceptional than the reflection of heat from mountain snow. Plants that absorb heat from the sun have just as great an effect on the atmosphere as do rocks, soil, rivers, seas, deserts and snowy mountains.

Not long ago a globally reputed environmental protection organisation confirmed, using monitoring data from remote sensing technology, that the afforested area of the earth’s surface was pitifully diminished. There are now very few areas covered by natural forests. It may appear that, in recent years, artificial afforestation in China has achieved great success. In line with government wishes, the amount of land covered by forests has been rising annually. More and more each year, people throughout China have happy memories of planting trees. But we should be suspicious of China’s afforestation programme, particularly regarding single-species forests.

Most manmade forests have a catastrophic effect on biodiversity; and the planting of single species also clearly influences carbon-storing capacities. Natural forests are the best choice for China. The way to obtain natural forests is not engineered afforestation, but rather natural cultivation. Because in a great many places all that is required is non-interference in the natural wilderness, it is certainly possible in terms of our climate requirements to reach the ideal “ecological reinstatement”.

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匿名 | Anonymous



Pine monoculture has biodiversity upside in UK

Yongfeng Feng writes:
"Most manmade forests have a catastrophic effect on biodiversity"

I just want to point out an exception. Pine monocultures are the only ways that the native red squirrel dominates the American-imported grey squirrel in the british isles.

Unimportant? Maybe, but it points to the endless difficulty of measuring biodiversity. How many squirrel species should be traded for insect species? Nature does not constrain our choices in clear-cut ways.


This comment has been revised by chinadialogue.

Default avatar
匿名 | Anonymous



Tree Planting May Also Cause Mistakes

We all believe that planting trees can improve the environment, just like taking drugs to cure illness. However, just like all the drugs have their side effects, we may destroy our environment by planting trees wrongly. We shall believe in the nature’s immune ability, not to disturb it and let it cure by itself, this way can be economical and save labour.

Default avatar
匿名 | Anonymous


Tony,你的意思是不是指红色松鼠比灰色松鼠能保持低比率的身体脂肪, 所以英国的部分地方需要保持林相单一?这是为了可以提供更多食物给松鼠吗?Teddy Wu

re:Pine monoculture has biodiversity upside in UK

Tony,do you mean that it is because the red squirrels just can keep a low rate of body fat than grey squirrels, some place in UK need to keep pine monoculture?
In order to provide more food to squirrels? Teddy Wu

Default avatar
匿名 | Anonymous


是的,如果我们去除林相单一(通常认为是“好的”) 我们也就去除了红色松鼠生存的最后栖所(“坏”)。
几年前, 我一直致力于开发生物多样性索引,以便于人们引用。我运用了财政股份单理论中的某些概念来衡量其“传播的”状况。但有一个名叫ket的红松鼠的例子指出:一种难于衡量生物多样性传播的环境,从物种生存的角度来说更好。



I am not sure why it is only in pine monoculture that grey squirrels don't drive out the red - do you know.

Yes, if we get rid of pine monoculture (usually thought "good") we also get rid of the last habitat the red squirrel survives in ("bad").

My point was to emphasise the difficulty of measuring and chosing bio-diversity levels once we have started to become aware of our meddling with ecosystems.

Years ago, I worked on trying to develop an index of biodiversity for CITES. I applied some of the concepts from financial portfolio theory to measure "spread". But the red squirrel example ket coming up: an environment with very low "measurable" spread of biological diversity, but one which might be better from the point of view of species survival.


Default avatar
匿名 | Anonymous



Poor "Renewable energy law"

This Law has been promulgated, but how is its effectiveness? There is still a long road ahead.