ASOMBANG R.N カメルーン高等教育研究省人文科学研究所, 人類学研究センター, 研究員
CHANDA R. University of Zambia, Faculty of Sciences, Senior Lecturer, 自然科学部, 上級講師
TSALEFAC University of Yaounde, Faculty of Social and Human Sciences, Lecturer, 人文社会学部(カメルーン), 講師
KUETE M. National Geographic Center, ISH/MESIRES, Head of Geographical Researches, 国立地理研究センター, 研究部長
DONGMO J.ーL. 国立ヤウンデ大学, 人文社会学部(カメルーン), 講師
OJYANY F.F. 国立ナイロビ大学, 文学部(ケニア), 教授
篠田 雅人 東京都立大学, 理学部, 助手 (30211957)
中条 廣義 中部大学, 国際関係学部, 教授 (80207315)
岩崎 一孝 北海道大学, 文学部, 助教授 (90176537)
武内 和彦 東京大学, 農学部, 助教授 (90112474)
八木 久義 東京大学, 農学部, 助教授 (80191089)
田村 俊和 東北大学, 理学部, 教授 (00087149)
DONGMO J. -L. University of Yaounde, Faculty of Social and Human Sciences, Professor
OJYANY F. F. University of Nairobi, Faculty of Letters, Professor
SHINODA Masato Tokyo Metropolitan University, Faculty of Science, Research Felllow
CHUJYO Hiroyoshi Cyubu University, Faculty of International Studies, Associate Professor
TAKEUCHI Kazuhiko University of Tokyo, Faculty of Agriculture, Associate Professor
IWASAKI Kazutaka Hokkaido University, Faculty of Literature, Associate Professor
TAMURA Toshikazu Tohoku University, Faculty of Science, Professor
YAGI Hisayoshi University of Tokyo, Faculty of Agriculture, Associate Professor
ASOMBANG R. N. Center for Anthropological Studies and Research, ISH/MESIRES, Researcher
|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1991 : ¥2,000,000 (Direct Cost : ¥2,000,000)
The field data obtained from the 1989-90 season research in the African savannas were analyzed and were featured into a publication that includes following results :
1. Northern Africa (Cameroon)
1) East Cameroon forest/savanna contact : A model for explaining savannization processes was constructed on the basis of the relationship between the structure and composition of semideciduous and gallery forests and soil profiles.
2) West Cameroon Highlands : Pollen analysis and radiocarbon datings of cores indicate that forest degradation followed by savannization began at 3, 000-2, 500 yr BP and intensified since 2, 000-1, 500 yr BP. Spreading of Podocarpus, a montane forest element, during the LGM to the lower elevations was also confirmed.
3) West Cameroon Highlands : A model showing patterns and processes of land and vegetation degradation over cattle-grazed grassy slope was constructed.
4) Sudano-Sahelian savanna zone : An attempt was made to formulate progressive land degradation under cond
itions of increased human impact and persistent drought.
5) Recently, deforestation of humid forests has been greatly accelerated due to shortened fallow period of slash-and-burn cultivation and to illegal exploitation of reserved forests.
2. Sothern Africa (Zambia, Zimbabwe and Malawi)
6) West Zambia : Geoecological analysis of soil profiles and radiocarbon dates of buried soils suggest that human impact creating "miombo" woodland over the Kalahari Sands dates back to to 2, 500 yr BP, widespread from 1, 000 yr BP and intensified from 400 yr BP.
7) Nyika Plateau : Widespread grasslands over the plateau have been derived from clearing of evergreen montane forests some 500 years ago for fuelwood by iron-smelting peoples, resulting in widespread soil degradation.
3. Throughout equatorial Africa, hitherto available data indicate that the degradation of forest vegetation and savannization have proceeded by the coupled effects of human activities and climatic aridification since 3, 000-2, 500 yr BP. Reconstruction, however, of more detailed history, call for more well-dated data.
4. Recent Subsaharan drought seems to be caused by decreased convective activities and may relate with a global-scale anomaly of Walker Circulation.
5. Landsurface-atmosphere interaction changes induced by "desertification" and savannization and their climatic and ecological implications remain unanswered.