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"Earth-friendly": Is it true?

Yasushi Morikawa
Professor at Faculty of Human Sciences, Waseda University

From the viewpoint of science, we would have to say "earth-friendly" and "environment-friendly" are emotional and even "strange" terms though they are often used in discussing environmental problems. Even if human beings do serious damage to the earth, the earth would be never destroyed, but only human beings would perish. For survival, we should be "human-friendly" rather than "earth-friendly." We need to recognize some "earth-friendly" products are actually "human-unfriendly." This problem is difficult to solve because we are too obsessed with emotional words like eco-something without any scientific evidence.

Eliminating incorrect assumption: acid rain

Over the last several years, science textbooks have discussed the acid rain problem together with photos showing dead forest. In compulsory education, it is believed textbooks always tell the truth. That is, an idea that acid rain results in dead forest is imprinted on us during the course of education. However, acid rain hardly leads to dead forest in Japan, for example. Though a typical scientific evidence indicating impact of acid rain on forest decline is measurement result on acidity of rain, dew, and mist, most data provided from the viewpoint of forest are photos showing dead forest. Besides acid rain data, there are a lot of evidences available including meteorological data and air pollution data provided that sufficient money and automatic measuring instrument are ensured. On the other hand, data representing impact itself are photos of dead forest only. (See Figure 1)

Figure 1

Take an example, though not so a good example. Assume a dead cat is found on the road without any wound. People think it is unfortunately hit by a car, and investigation on traffic amount might be undertaken. However, we cannot recognize what the cat died of from its appearance. Of course, there are many causes of death for cats such as old age and heart attack. This is also applicable to the acid rain problem. Investigation from the viewpoint of environment is not enough to identify a true cause. We should clarify a cause of the cat's death in the above cat case, or internal mechanism of forest decline in the forest case.

To solve environmental problems, it is important to determine whether the relationship between two incidents is cause-and-effect or parallel. Thus, scientific evidences are required for problem solution.

Agreeing in general, but not compromising on details: Kyoto Protocol

To restrain global warming, many countries agreed the Framework Convention on Climate Change. This is a so-called gentleman's agreement and agreement in general. However, some countries including the Unites States are reluctant to agree the Kyoto Protocol, a specific action, in consideration of their domestic situations.

Companies selling "earth-friendly" products are regarded as good companies that give special consideration to environment. In spite of an increased number of such good companies, Japan's carbon dioxides emissions are still increasing. In the Kyoto Protocol, Japan promised reduction by 6% compared to 1990, but emissions are increased by 7.6% in 2002, which means Japan is required to achieve reduction by 13.6% by 2012. It is doubtful whether we can do. Only companies are not responsible for reduction of the carbon dioxides emissions. Since many causes of the increase are related to consumer goods and transportation, we are also responsible. Can we make efforts? Though stop of global warming is general agreement within the country, how is it at each family or individual level? Now Christmas holiday is coming. Does any company or organization stop Christmas illumination this year? Though TV stations stopped broadcasting in the midnight when the oil shock affected our life, I do not feel any such mood now.

Plant and burn: Rehabilitation of tropical rain forest

Figure 2

I will conclude this article with my own experience in study abroad. (See Figure 2) In the tropical zone, there are many abandoned barren lands due to excessive slash-and-burn, which makes spontaneous regeneration of forest difficult. Though rain forest rehabilitation projects funded by Japanese government, enterprise, and NGO have been carried out, forested sites often reverted to burnt lands. This is a repetitive cycle of "plant and burn". Why? Basically forest rehabilitation projects are limited to a fixed period, and will not continue for 10 or 20 years. When planting is in progress on a barren land, people in the local community are happy because they can gain income as wages for planting. When the project is complete, however, trees begin growing, but are not big enough to bring wood income. Local people have not gained any benefit yet. Thinking future benefit is uncertain promise, they attempt to burn the land to earn monthly or annual income from slash-and-burn farming and production of cash crops. People are pleased with planting because even a small amount of green can be burnt into wood ashes, and then fertilizer. This is why a cycle of "plant and burn" is repeated and rain forest rehabilitation is difficult to achieve. Unless a project provides system for ensuring that people in the local community can gain sustainable income, the project is regarded as self-complacent because it is limited to "planting".

Yasushi Morikawa
Professor at Faculty of Human Sciences, Waseda University


The author was born in 1944
March 1973 : Doctor of Agriculture at Graduate School of Agriculture, University of Tokyo
April 1973 : Researcher at Forestry Research Institute, Ministry of Agriculture, Forestry and Fisheries
1991 : Leader at the Department of Plant Ecology, Forestry and Forest Products Research Institute January 1995 Current post

Related Publications

Following articles are in Japanese
Yasushi Morikawa, 1997, "Cause of forest decline", Asahi Hyakka: World of Plants, Volume 11, pp. 254-256
Masayuki Seto, Yasushi Morikawa, and Tokutaro Ozawa, 1998, "Introduction to environmentalism for liberal arts students", Yuhikaku ARMA, p. 198
Yasushi Morikawa, 1999, "Ecophysiology of plants" in "Tree Health Research" edited by Kazuo Suzuki, Asakura Publishing Co., Ltd. pp. 83-109
Yasushi Morikawa, 2004, "Evaluation and problems concerning forest as CO2 sink", Resources and Environmental Engineering, Volume 51 Number 4, pp. 228-233