To monitor the capacity of Asian forests to absorb carbon dioxide in the atmosphere, the Research Institute for Environmental Management Technology (Koh Harada, Director) of the National Institute of Advanced Industrial Science and Technology (AIST; Hiroyuki Yoshikawa, President) have been promoting the establishment of a network for monitoring of carbon uptake in Asia (AsiaFlux Network) in cooperation with several Asian countries and with the Forestry and Forest Products Research Institute (Motoaki Okuma, President), the National Institute for Agro-Environmental Science (Yohei Sato, chief director), the National Institute for Environmental Studies (Ryutaro Otsuka, President), and Hokkaido University (Mutsuo Nakamura, President).

As part of the program "Establishment of the international leadership of Japan" of the Japanese Science and Technology Agency (JST), Nobuko Saigusa (Senior Researcher) et al. of the Atmospheric Environment Study Group (Hiroaki Kondo, Group Leader) of AIST have offered the first training course targeted at specialists in Asian with the purpose of disseminating technology and education for the measurement of carbon dioxide uptake by forests. This course was held at AIST, Tsukuba from August 21 through 30, 2006.

The purpose of the training course is to disseminate the technology for continuous measuring of carbon dioxide uptake by forests using the eddy covariance technique based on meteorology. About twenty specialists in meteorology, forestry, plant ecology and other fields attended the course from ten Asian countries and regions, namely India, Indonesia, Thailand, The Republic of Korea, The People's Republic of China, Bangladesh, The Philippines, Vietnam, Malaysia and Taiwan. The intensive course, of 10 days’ duration, was structured into: 1) measurement theory, 2) comprehensive measurement technology including equipment installation and maintenance, and 3) data processing technology to calculate carbon dioxide absorption by forests.

This training course is expected to contribute to the establishment of a database for observed data on carbon dioxide uptake rate, as well as to the improvement of the accuracy of the compiled data, and to the strengthening of cooperation between specialists and policy makers in Asia.

Tower for observation (Left) and section of the measurement equipment.

Increase of the concentration of carbon dioxide in the atmosphere is considered to be one of the main causes of global warming. It is important, then, to assess the speed of this increase and to establish the effect that measures to control the emissions of carbon dioxide have on the changes in concentration of this compound in the atmosphere. To this end, it is crucial to fully understand the role of forests, which cover approximately one third of the earth’s surface. They absorb carbon dioxide during photosynthesis and at the same time release carbon dioxide into the atmosphere by the respiration of plants and the decomposition of organic compounds in soil, constantly carrying out exchange of carbon dioxide in the atmosphere. This exchange rate is intricately influenced by the amount of solar radiation, the air temperature and other meteorological conditions. Forest disturbance by logging or fire also has a considerable effect on the fluctuation of carbon dioxide concentration in the atmosphere, as large amounts of carbon dioxide are discharged into the atmosphere in a short period of time.

Asia covers a wide band of latitude where important ecosystems co-exist, extending from the sub arctic zone with the northern larch forests as huge reservoirs of carbon, to the tropical region where the tropical rainforests include a diversity of species unparalleled in the world. Regarding the global warming problem, it is crucial to establish a long term monitoring network that allows measurement of the exchange rate of carbon dioxide to determine the photosynthesis and respiration capabilities of living organisms in the forest. Up to now, measurement of the amount of carbon dioxide exchanged in the forest has been based on the biometric method (measuring the diameter growth of trees and shrubs) or on the most recently established methods of micrometeorology (the eddy correlation method, which is based on the measurement of the variation of density of carbon dioxide in the air). In the case of the eddy correlation method, it is necessary to acquire knowledge of meteorology as well as the technology to operate at least ten types of equipment involved in the measurement, so it becomes imperative to develop the human resources that can carry out these tasks. This role is being fulfilled at only a limited numbers of universities and research institutions in Japan, the Republic of Korea, and so on.

In order to assess the amount of carbon dioxide that is being absorbed by forests in Asia, AIST, within the framework of the "Establishment of the international leadership of Japan" program of JST, has joined efforts with several Asian countries as well as with the Forestry and Forest Products Research Institute, the National Institute for Agro-Environmental Science, the National Institute for Environmental Studies, and Hokkaido University, to promote the establishment of a network for Monitoring of Carbon Uptake in Asia (AsiaFlux Network).

Especially, the Forestry and Forest Products Research Institute and the National Institute for Agro-Environmental Science have promoted the expansion of the monitoring network for forest ecosystems and cropland ecosystems, whereas the National Institute for Environmental Studies has tackled the opening of international workshops and the establishment of databases. AIST has utilized the experience acquired in applying the eddy covariance techniques to difficult and remote areas (forests with complicated topography, remote areas abroad, etc.) to improve the computation methods for monitoring carbon dioxide absorption by forests, and, together with Hokkaido University has tackled the educational issues related to dissemination of these monitoring technologies. 

The aim of the first training course is to disseminate basic meteorological theories and measurement technologies of carbon dioxide using eddy correlation. The course has been divided into three parts. The first part presents the basic theories through lectures given by specialists in the field of meteorology from Japan, South Korea and the USA, giving essential knowledge on micrometeorology in a short period of time and bringing the participants to the level of expertise of graduate students in Japanese universities. The second part of the course consists of practical measurements carried out indoors and outdoors, giving the participants hands on experience with installation and use of diverse types of equipment and with practical measurements and data collection. At the same time, researchers with wide experience in this kind of measurement, will assist in the field observations to stress the caution points, especially on prevention of damage to the equipment caused by instability of power source, protection against thunderbolts, damage caused by animals, and other difficulties likely to arise during long term monitoring. The third part of the course is devoted to using the collected data to carry out analysis in order to calculate carbon dioxide absorption by the forest. The eddy correlation method allows 10 continuous measurements per second of wind velocity and concentration of carbon dioxide, which implies that a large amount of data is collected from field monitoring. From this large amount of data, after eliminating the abnormal values and through many steps of data processing, it is possible to calculate the average value of carbon dioxide absorption by forest in periods of 30 minutes to 1 hour. Learning how to process each of these kinds of data, the participants will be able to freely edit the computation programs to carry out data processing on personal computers.

In the present course, the participants from Asian countries will learn the most advanced techniques for monitoring of carbon dioxide absorption by forests, and, at the same time, by participating in the establishment of the monitoring network, they will learn that strengthening the cooperation network beyond borders is indispensable. Furthermore, they will learn that by long term monitoring of photosynthesis, transpiration, respiration and other activities of living organisms, it is possible not only to prevent the advance of global warming but also to preserve the water conservation function of the forests and to protect the biological diversity in the forests.

The course is scheduled to also be offered next year. These educational and monitoring technology dissemination activities are expected to contribute to systematic accumulation and improvement in the quality of observed data of carbon dioxide absorption by forests in Asia. Furthermore, these activities will also strengthen the cooperation between researchers and policy makers in Asia.