Ecol. Res. 6: 127-128, 1991

Preface

The 5th International Congress of Ecology (INTECOL) was held at Yokohama from August 2 3 - 30, 1990. The Congress theme was "Development of Ecological Perspectives for the 21st Century". Special emphasis was given to the following three ecological issues; Future perspectives in ecology, Ecology and human activities, and Ecology of Asia. Concerning these issues, seven plenary sessions, over 100 symposia, more than 500 poster presentations, and more than 30 workshops were held during the Congress. Needless to say, ecological phenomena, in themselves, are extremely broad and complex, and unsurprisingly, no theories have been able to explain the entire features of for example, community structure. We firstly need many alternative views and approaches for examining ecological characteristics. Secondly, it is essential that we do not select just one of these views, but rather integrate them, in order to obtain better understanding of the phenomena addressed. The scientific approach is, of course, pannational or worldwide, but if is also conditioned by individuals and nationalities, especially on languages and other traditional thinking. In my opinion, all ecological units such as the population, the community, and the ecosystem, are not assemblages of organisms or other organic units but assemblages of relations between/among organisms or other organic units. Furthermore, ecological networks are not the tight or deterministic entities that most ecologists consider them for examination and analytical purposes, but are actually much more loose and equivocal. Not pannational but international approaches, in the literal sense, would advance future trends of ecology, I believe. During the Congress the four plenary sessions and more than 50 symposia were devoted to the issue of future perspectives in ecology. During the past few decades, environmental problems all over the world, and in a global scale, have, unfortunately, become more and more serious. Some of these problems have been understood by general public over the past few years, slightly too late but fortunately, not completely too late. I should say. So, the second main issue of this Congress concerned the influence of human activities on ecological features, especially global changes of climate and ecosystems. For this purpose, ecology itself should interact with related natural, technological, social and sciences. On this issue the two plenary sessions and about 40 symposia were h e l d . The third issue was devoted to regional ecology in Asia, especially tropical and subtropical ecosystems including agriculture and conservation. Many plenary sessions and symposia included presentations on this theme but one specific plenary session and about 15 symposia were devoted exclusively to this issue. Unfortunately, I personally have had little experience of ecological work in subtropical and tropical Asia, but have studied in tropical Africa, in Lake Tanganyka, since 1977. In my case, I am fortunate enough to have more than 15 African scientists and scientific technicians working together with Japanese and

128 British workers. Although I took the initiative at the first step for our cooperative research, I am delighted to say that scientists in those countries are now gradually taking the initiative for general research on the lake. Ecological issues and problems in so-called developing countries are extremely serious but should be analyzed mainly by scientists in each area. Decisions related to sustainable land-use and conservation, of course, should also be made by people in those countries. The Congress presented an excellent opportunity to further discuss this kind of progress. More than 2300 participants from 82 countries attended this Congress. I am very proud by the extremely high level of presentation and enthusiastic discussion that took place on the broad field of ecology and its related sciences during the Congress. Proceedings and books have and will be published on many symposia and workshops, but now five plenary articles are published as a number of Ecological Research, the English language journal of the Ecological Society of Japan. The 5th International Congress of Ecology was sponsored together by the Science Council of Japan and the Ecological Society of Japan, with the International Association for Ecology. Co-sponsorship was provided by the Ministry of Education, Science and other Japanese ministries and agencies, many scientific societies and associations related to ecological sciences, and especially by the Kanagawa Prefectural Government, the Yokohama Municipal Government, the Kawasaki Municipal Government, the Defense of Green Earth Foundation, and the Asahi Newspaper Co. Many foundations, companies, agencies and individuals also supported financially and many other aids in various ways. I would like to acknowledge the kind sponsorship and helps of all these bodies and individuals. Hiroya KAWANABE The Convener of the Organizing Committee for the INTECOL-90. The President of Ecological Society of Japan. Department of Zoology, Faculty of Science, Kyoto University, Kyoto, 606-0L and the Centre for Ecological Research, Kyoto University, Otsu, 520-01, Japan.