the land cover of africa for the year 2000 p. mayaux, e. bartholomé, m. massart, c. van cutsem, a....

The Land cover of Africa for the year 2000

The Land cover of Africa for the year 2000

P. Mayaux, E. Bartholomé, M. Massart, C. Van Cutsem, A. Cabral,

A. Nonguierma, O. Diallo, C. Pretorius, M. Thompson, M. Cherlet,

J-F. Pekel, P. Defourny, M. Vasconcelos, A. Di Gregorio, S.Fritz,

G. De Grandi , C.Elvidge, P.Vogt, A. Belward

The overall contextThe overall context

• 30,000,000 km2

• From dry deserts to tropical rain forests

• Evergreen (forests, deserts) and seasonal (savannahs, grasslands) ecosystems

• Isolated continent no overlap with other windows

• 1 continental window (baseline map) + regional windows (improvements)

Characteristics of the productCharacteristics of the product

• Collaboration between many institutions: FAO, Instituto Investigação Cientifica Tropical (Lisbon), Université Catholique de Louvain (Louvain-la-Neuve), Agrhymet (Niamey), CSIR (Pretoria)…

• Various techniques: statistical averaging and clustering (Louvain-la-Neuve), composition on albedo and tree classifiers (Lisbon), clean NDVI & NDWI profiles and clustering (CCR)

• Data used: SPOT VEGETATION, ERS & JERS SAR (flooded forests), DMSP (cities)

• Legend has put the accent on the savanna and the forests• The current product is still in improvement

Cleaning up of the NDVI profilesCleaning up of the NDVI profiles

• Elimination of low values• Interpolation over long periods

Monthly max NDVI and min NDWIMonthly max NDVI and min NDWI

August – April - January

Forests Forêts Closed evergreen lowland forest Degraded evergreen lowland forest Montane evergreen forest (> 1000 m) Swamp forest Mangrove Mosaic Forest / Croplands Mosaic Forest / Savanna Closed decidous forest (Miombo)

Forêt dense humide Forêt dense dégradée Forêt de montagne Forêt marécageuse Mangrove Mosaïque agriculture / forêt humide Mosaïque forêt / savane Forêt décidue dense(Miombo)

Woodlands, shrublands and grasslands Savanes Deciduous woodland Deciduous shrubland with sparse trees Open deciduous shrubland Closed grassland Open grassland with sparse shrubs Open grassland Sparse grassland Swamp bushland and grassland

Savane boisée décidue Savane arborée à arbustive décidue Savane arbustive décidue Savane herbacée dense décidue Savane herbacée ouverte à faible strate arbustive Savane herbacée ouverte Pseudo-steppe Savane herbacée et arbustive inondée

Agriculture Agriculture Croplands (>50%) Croplands with open woody vegetation Irrigated croplands Tree crops

Agriculture (>50 %) Mosaïque agriculture / végétation sèche Agriculture irriguée Vergers

Other land-cover classes Autres occupations du sol

Bare soil Salt hardpans Waterbodies Cities

Sol nu Dépôts salins Eau Villes

MarocMaroc

• Urge agricultural areas

• Urban settlements

• Meditteranean vegetation

• Inversed vegetation cycle

Irrigation in the Lybia desertIrrigation in the Lybia desert

• Urge irrigation areas

• Urban settlements

• Desert

• Salt hardpans

Nile DeltaNile Delta

• Urge cities (Cairo, Alexandria)

• Free water and swamp grasslands, and irrigated agriculture

• Desert

SenegalSenegal

• Urge agricultural areas (“Bassin Arachidier”

• Mangroves (Saloum, Casamance)

• Urban settlements

• From sparse grasslands to woodlands

• Remnants of tropical forests (Basse Casamance)

Chad LakeChad Lake

• Chad lake

• Free water and swamp grasslands (“prairie flottante)

• Agriculture

• From desert to closed shrublands

Internal delta of Nile Internal delta of Nile

• Urge areas of swamp grasslands, water

• From shrublands to dense woodlands

MalawiMalawi

• Agriculture

• Miombo woodlands

• Large lake

South D.R. CongoSouth D.R. Congo

• Wet miombo woodlands

• Swamp grasslands

• Shrublands and grasslands

• Woodlands mixed with agriculture

Wet miombo woodlandsWet miombo woodlands

Delta of the OkavangoDelta of the Okavango

• Swamp grasslands and shrublands

• From grasslands to woodlands

• Salt hardpans

Cape TownCape Town

• Intensive agriculture (wheat, vineyards)

• Vegetation related to topography

• Large urban settlements

• High botanical biodiversity

Forest blocks in GhanaForest blocks in Ghana

• Volta Lake

• Lagoons

• Urban settlements

• Forest reserves

• Forest / croplands / savanna mosaic

Central “Cuvette” of Congo RiverCentral “Cuvette” of Congo River

• Swamp forests

• Swamp grasslands (“prairie flottante)

• Agriculture mixed with fallows and forest

• Enclosed savannas

Congo Basin forestsCongo Basin forests

• Agriculture mixed with fallows and forest along the former “paysannats”

• Penetration by the logging tracks

Niger deltaNiger delta

• Mangroves

• Lowland and montane forests

• Urban settlements

• Forest / croplands / savanna mosaic

• Woodlands mixed with agriculture

Montane forestsMontane forests

• Kilimanjaro, Mehru…

• Montane forests

• Closed grasslands

• Agriculture

MadagascarMadagascar

• Montane and lowland rain forests

• Dry deciduous forests

• Secondary forests & rural complex

• Mangroves

• Grasslands and shrublands

• Thicket

Global land-cover mapsGlobal land-cover maps

IGBP DIS-Cover University of Maryland

GLC 2000VGT colour composite

The locust windowThe locust window

FAO / JRC

Qualitative validationQualitative validation

Agricultural areasAgricultural areas

LimitationsLimitations

• Confusion in the agricultural areas (mixed with natural vegetation)

• Seasonal cycle of the vegetation could be more exploited (number and period of vegetation cycles)

• Local legends do not fit with the continental one

Necessity of regional products