Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Tokyo Metropolitan University|
KADOMURA Hiroshi Faculty of Science, Tokyo Metropolitan University, Professor, 理学部, 教授 (80087064)
DAPOLA Evari ブルキナファソ、ワガドグ大, 言語人文社会学部, 講師
OUSSEINI I. Faculty of Human Sciences, University of Niamey, Niger, Lecturer, 人文学部, 講師
ZOGNING A. Division of Geographical Research, National Institute of Cartography, Ministry o, 地理研究部, 部長
DONGMO Jeanー カメルーン、ウガンデレ大学, 人文社会学部, 教授
CHUJO Hiroyoshi Faculty of International Studies, Chubu University, Professor, 国際関係学部, 教授 (80207315)
TAKAOKA Sadao Faculty of Science, Tokyo Metropolitan University., Research Fellow, 理学部, 助手 (90260786)
HORI Nobuyuki Faculty of Science, Tokyo Metropolitan University, Professor, 理学部, 教授 (40087143)
DA DAPOLA E. Faculty of Languages, Human and Social Sciences, University of Ouagadougou, Burk
DONGMO J.-l. Faculty of Arts, Letters and Human Sciences, University of Ngaoundere, Cameroon,
OUSSEINI I. ニジェール,ニアメイ大学, 人文学部, 講師
DONGMO J.ーL. カメルーン,ンガウンデレ大学, 人文社会学部, 教授
篠田 雅人 東京都立大学, 理学部, 助教授 (30211957)
|Project Period (FY)
1993 – 1994
Completed(Fiscal Year 1994)
|Budget Amount *help
¥12,000,000 (Direct Cost : ¥12,000,000)
Fiscal Year 1994 : ¥6,000,000 (Direct Cost : ¥6,000,000)
Fiscal Year 1993 : ¥6,000,000 (Direct Cost : ¥6,000,000)
|Keywords||Land degradation / Desertification / Soil erosion / Drought / Human impact / Subsaharan Africa / Sahel / Sudan|
The present project aims at investigating the detailed physical processes and spatial patterns of land degradation in Subsaharan Africa, the phenomenon collectively called by the term 'desertification', due to the combined effect of climate variations and human activities. Field works were carried out along the two transects in the West African Sudano-Sahelian Region. The main results obtained can be summarized as follows :
(1)Throughout the areas surveyed, lateritic cuirass-capped plateau surface and glacis or pediments fringing scarp foot of hills and plateaux are the landform types which are most prone to degradation.
(2)Both patterns and processes of progress of and recovery from land degradation, are more closely related with local edaphic conditions rather than regional precipitation pattern.
(3)As long as viable seeds are preserved in the soils, rapid revegetation can be achieved over alluvial plains and sand dunes in response to the return of good rains.
(4)Over the "fossil sand dunes and sheets", which are located to the for south of the desert boundary and receive an annual rainfall of 600-700mm sporadic and selective degradation has caused by shifting sands activated by the destruction of vegetavive cover due to overgrazing and excessive cultivation.
(5)It must be emphasized that the land degradation due to moving sands is not caused by the southward march of the Sahara Desert but by the remobilisation of once fixed sand dunes or sheets owing to the coupled effect of human activities and persistent drought conditions.
(6)In order to answer the questions related to the irreversibility and/or resilience in land and vegetation, long-term observations at a time-scale of 10-20 years in several fixed areas and transects are indispensable.