April 26, 2011


Plant Native Trees, Recreate Forests to Protect the Future: Respected Ecosystem Scientist Akira Miyawaki

Keywords: Newsletter 

JFS Newsletter No.103 (March 2011)
"Japanese Philosophers/Leaders for Sustainability" (No. 2)

Dr. Akira Miyawaki is a vegetation ecologist, professor emeritus of Yokohama National University, and the director of the IGES-Japanese Center for International Studies in Ecology. Dr. Miyawaki's specialty is vegetation ecology, and he has investigated both natural and already long-disturbed vegetation landscapes for over 40 years, not only in Japan but also around the world. He promotes forest regeneration using the local potential natural vegetation.

Potential natural vegetation (PNV) is a concept used to investigate and evaluate the theoretical potential of the natural environment of an area that may have had its environmental and geographical conditions modified by human activities over time. The concept is useful for the regeneration of the natural vegetation. It was first proposed by German vegetation ecologist Reinhold Tuexen in 1956 as a new idea to understand nature.

The idea of creating a forest by closely planting together different types of trees of the potential natural vegetation of the land, based on the PNV concept, is called the Miyawaki Method. Closely and randomly planting many types of seedlings results in creating forests of tall and medium high trees as found in natural forest systems, which will reinforce diversity and resistance and will lead to co-existence of plants and draw from the vital energy of the trees themselves. Weeding and other human support for tree growth are required only for the first three years after planting. Thereafter, forest management is left to nature. These are the main features of the Miyawaki Method.

Dr. Miyawaki has instructed people on planting in over 1,700 areas around the world, including over 1,400 sites in Japan as well as in Borneo, Amazonia, Kenya, and China. He has been involved in the planting of over 40 million native trees, together with companies and citizens, to contribute to forest regeneration.

In 2006, he was awarded the 15th annual Blue Planet Prize by the Asahi Glass Foundation, an award given to researchers who have contributed to the environmental conservation of the Earth, a first for someone from Japan. Let's look back here at the life of Dr. Miyawaki, who has persisted in using a hands-on approach to promote greening, and consider our future based on what he says plants are trying to tell us.

Encounter with the Potential Natural Vegetation Concept

Dr. Miyawaki was born in 1928, the fourth son of a farmer in Okayama Prefecture, western Japan. Just before the end of World War II, in 1945, he entered the Tokyo College of Agriculture and Forestry (now the Tokyo University of Agriculture and Technology) to become a biology teacher, and then worked as a high school teacher at his alma mater. He quit the job after working one year, however, because of his desire to continue his studies, and entered the Biology Department of Hiroshima University of Literature and Science, close to his hometown, to become a researcher specializing in weed ecology.

In 1952, Dr. Miyawaki was employed as an assistant at Yokohama National University. He devoted himself for six years to field work studying the weed communities of the Japanese islands for 60 days each season, totaling 240 days a year. In the end, he contributed a comparative research paper on the forms of weed roots in German to a botanical journal. His paper attracted the attention of Professor Reinhold Tuexen, then-director of the Federal Institute for Vegetation Mapping in Western Germany, and opened a path to study in Germany, which was a turning point in his life.

After 56 hours of travel from Japan, Miyawaki arrived in Germany on September 30, 1958, and what awaited him from the next day forward was day after day of field work. The main research site he worked on was Luneburger Heide, the largest nature reserve in the country. The area had long been degraded, and was a non-productive wasteland because of repeated overgrazing, deforestation, and other human activities over a few thousand years.

During his research, for example, one day Dr. Miyawaki would spend the entire day digging holes to study the relationship between the soil profile and the vegetation, and other days he would devote to organizing a tremendous amount of data collected in the field after bringing them back to the research institute, all the while surveying vegetation along the way. Day after day, he worked on tasks requiring much patience in order to figure out what types of vegetation and ecosystems had existed in the vast forest of the past by gathering and putting together the subtle clues left behind.

Unable to put up with working solely on such tasks, he finally complained to Dr. Tuexen, saying, "I want to work on literature research and other, more scientific studies." The professor's reply was: "You should go out into the field first, use your whole body as a measuring instrument, and study the results of nature's ongoing experiments for yourself by watching, smelling, tasting, and touching them."

After publishing an academic dissertation on the study of weed communities, he was thoroughly trained by Dr. Tuexen on the concept of potential natural vegetation and the methods of its study and assessment, as well as on the research methods of phytosociology, which Wikipedia defines as "the branch of science which deals with plant communities, their composition and development, and the relationships between the species within them." Eventually, his research interest shifted from weeds to forests.

Overcoming Years of Obscurity

Ten years after returning to Japan at the end of the 1960s were Dr. Miyawaki's years of obscurity. The science of phytosociology, which he brought back from Germany, did not receive any significant recognition in the academic community in Japan at the time. Moreover, the philosophy of protecting nature, a movement growing in the United States and Europe, and a proposal to prevent natural disasters by planting trees, were not accepted readily in Japanese society, which still prioritized economic growth overall. Also, around that time, many universities were becoming embroiled in campus activism, which often hampered his studies in the lab.

Against this backdrop, he conducted thorough field work study on vegetation using the survey method of phytosociology by walking all over the lands of Japan, starting from Amami Island, which had just been handed back to Japan from the United States. He compiled the collected data and created existing vegetation maps, which showed the then-current vegetation distribution in the country on maps, as well as potential natural vegetation maps.

"Thanks to these ten years of 'down-to-earth' surveys and research, I was able to establish the foundation for the development of my lifelong research activity," writes Dr. Miyawaki in one of his books, as he looked back on his life.

In the 1970s, the destruction of the natural environment in many parts of the country became more widely known to the public, and tree planting became required under the Factory Location Act, which was established as a measure to protect nature. From then on, the staff of companies and municipalities who had become more proactive in nature protection than others started to visit his lab.

It was around that time when his research achievements started to be recognized in Japan and abroad, and phytosociological research started to bloom all at once in the academic community of plant ecology in Japan. This trend eventually led to the publication of a monumental achievement in vegetation science, a massive work called "Vegetation of Japan," which totaled 6,000 pages in ten volumes. Started in 1980, it required ten years to complete and involved a total of 116 botanists.

One Important Lesson: Learn from "Chinju-no-Mori", Community Forests

On land changed by humans, the only way to assess potential natural vegetation is by uncovering subtle information provided by nature on the site. It was in community forests and groves around residences, etc., that still remained around temples, shrines, villages, and other places in Japan where clues were found for Dr. Miyawaki's assessments.

In Japan, since ancient times, there has been a culture in which, when people create farms and villages by reclaiming land, the natural environment of the places vulnerable to human interference, including ridgelines, steep slopes, and water edges, had been enshrined and left untouched as sanctuaries. In this way, forests and groves free from human interference for centuries -- each of which has a stable multilayer community consisting of the tree layer, or the main tree species, the sub-tree layer, the shrub layer, and the herb layer -- have served as precious time capsules for following generations to explore.

The results of the field surveys of the Japanese archipelago showed that its potential natural vegetation consists of evergreen broad-leaved trees like Castanopsis, Persea, and evergreen oak in most areas, except mountain areas in the Tohoku region and Hokkaido. The results also revealed that only 0.06 percent of the evergreen forests in the potential natural vegetation regions remained, because they had been drastically transformed or had disappeared over the century due to the impact of human activities.

Mandate: Create Life-Protecting Forests

The "Native Forest by Native Trees" activity proposed by Dr. Miyawaki was started on the site of the Oita Works of Nippon Steel Corporation in 1971. The forest -- the fruit of the earnest efforts of concerned parties -- was created by people picking up acorns in nearby community forests and growing them into seedlings. It developed into a large forest, with a canopy of 20 meters and larger, and now serves to prevent disasters and conserve the environment. The forest will be handed down to following generations as a life-protecting forest providing a fire-prevention function against earthquakes and their resulting great fires, and a function to weaken the power of waves when a tsunami comes. Triggered by the results of this effort, various companies, local governments, and non-governmental organizations started their own initiatives to create forests using his method.

In 1976, vegetation surveys were started in Southeast Asia. Since then, many activities to recreate forests using native trees based on proven scientific knowledge have been conducted by regional leaders and citizens in destroyed forests and regions concerned about desertification. These activities include rejuvenation of Bornean and Amazon rainforests, cooperation with the Green Belt Movement at the equator in Kenya, tree planting along the Great Wall of China, and creating the Urban Forest in Shanghai.

Miyawaki has probably been asked many times: "Why do you plant trees?" His answer to this question is very simple. He says, "Forests are life itself. Humans have survived until today supported by forests. The life for surviving tomorrow begins with creating true 'forests of life' by planting trees today."

"I want to live at least another 30 years, which is biologically possible, to create future-oriented forests of life in accord with natural rules and ecological conditions together with people throughout the world," Miyawaki continues, who turned 83 years old this year. Today, as always, he is planting trees in the field in Japan and abroad.

In order to realize that we will surely have a bright future for all life forms, it is hoped that as many people as possible will participate in activities to create forests of life, which most often begins with just a tiny acorn in our own native forests.

Further reading: Miyawaki, A., Elgene O. Box (2006) The Healing Power of Forests: The Philosophy behind Restoring Earth's Balance with Native Trees

Written by Kazumi Yagi

* We will be occasionally issuing this series to feature Japanese people who have pursued unique activities from their own perspective, and have moreover achieved outstanding performance in the fields of environmental protection and sustainability.