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Appendix 2. Environmental units

(Maps: see Figure 6)

Key to the Inventory

The inventory format uses a system of conventions to summarise the standard properties of 83 units identified in the SAZ of sub-Saharan Africa. The properties are arranged in 9 lines as follows:

LINE 1: IDENTIFICATION

Environmental unit number (1-83)
Moisture regime

d dry (75-120 days length of growing period)
m moist (120-180 days length of growing period)
* indicates adjustment to the 120 day isoline to avoid fragmentation of unit

Country abbreviation (first and last letters only, e.g. SL Senegal)
Size: in square kilometres rounded to nearest 5,000 km2

LINE 2: SOIL CLASSES (Soil)

Where only one letter is shown, this soil is dominant over 50% or more of the area. Where two letters, separated by a dot, are shown, the two soils are dominant over 66% or more and letters following + are subsidiary soils covering over 25% of the area. (J) (G) or (l) mean that these important soils are present but cover less than 25% of the area. A similar notation is used for other variables.

Soils: A Acrisols
B Cambisols
F Ferralsols
G Gleysols
I Lithosols
J Fluvisols
L Luvisols
N Nitosols
Q Arenosols
R Regosols
S Solonetz
T Andosols
V Vertisols
W Planasols
X Xerosols
Y Yermosols
Z Solonchaks

LINE 3: DEGRADATION RISK (Deg). North of Lat. 2°N

E3 Water erosion very high (over 200t/ha/year)
E2 Water erosion high (50-200/ha/year)
E1 Water erosion moderate (10-50/ha/year)
W3 Wind erosion very high (over 200t/ha/year)
W2 Wind erosion high (50-200/ha/year)
W1 Wind erosion moderate (10-50/ha/year)
S3 Salinization & sodication very high (over 5 mmhos/y)
(over 3 ESP/y)
S2 Salinization & sodication high (3-5mmhos/y)
(2-3 ESP/y)
S1 Salinization & sodication moderate (under 2mmhos/y)
(under l ESP/y)
C3 Chemical degradation very high
C2 Chemical degradation high
C1 Chemical degradation moderate
P3 Physical degradation very high
P2 Physical degradation high
P1 Physical degradation moderate
B3 Biological degradation very high
B2 Biological degradation high
B1 Biological degradation moderate
R Rock debris or outcrops
n.d. no data

The degradation conventions are placed under the soils to which they refer.

LINE 4: GRASS COVER (Gr)

Major Species
A Aristida
AN Andropogon
C Chloris
CE Cenchrus
CH Chrysopogon
E Eragrostis
EX Exotheca
H Hyparrhenia
HE Heteropogon
L Loudetia
P Pennisetum
PA Panicum
PE Pentaschistis
S Setaria
SO Sorghum
T Themeda
UF Undifferentiated forest
UFG Undifferentiated floodplain
UG Undifferentiated grassland
UM Undifferentiated mountain vegetation
US Undifferentiated swamp

followed by the associated vegetation category:

des desert
gr grassland
sav associated with savanna
st associated with steppe
th associated with thicket bush
tr st associated with tree steppe
Wd associated with woodland

LINE 5: VEGETATION CLASS (V)

The number of the mapping unit is given, followed by a description using the following abbreviation:

aqu aquatic
bush bushland
decid. Deciduous
evergr evergreen
gr grassland
mont. Montane
sec. Secondary
undif. Undifferentiated
veg. Vegetation
wd. Woodland
mopane Colophospermum mopane

LINE 6: DESERTIFICATION RISK (Des)

L low
M medium
H high
VH very high

LINE 7: CATTLE DENSITY (CD)

Number per square kilometre

NP

National Park

LINE 8: POPULATION DENSITY (PD)

Number per square kilometre

CSZ

Close Settled Zone

LINE 9: TSETSE FLY SPECIES PRESENT (T)

G.a Glossina austeni
G.b Glossina brevipalpis
G.f. Glossina fuscipes fuscipes
G.l Glossina longipalpis
G.ln Glossina longipennis
G.m Glossina morsitans
G.p Glossina palpalis
G.pd Glossina pallidipes
G.s Glossina swynnertoni
G.sc Glossina schwetzi
G.t Glossina tachinoides
- Tsetse absent
? Tsetse cleared.

LOCATION INDICATORS

(N) (NE) (E) (SE) (S) (SW) (W) (NW) and (C) - central, appearing underneath a convention, indicate that the property is located in that part of the environmental unit.

1d SL SENEGAL     (20,000 km2)
Soils Q        
Deg W1 E1/W1 + W2 (W3)
  (C) (E)   (WC) (W)
Gr CE sav        
V 43 Sahel Acacia wooded gr & decid bush  
Des M        
CD 13        
PD <1 25-100 + 1-10  
  (E) (W)   (C)  
T -        
1m SL SENEGAL   (35,000 km2)
Soils Q      
Deg E1/W1. W1 + (W3)
  (E) (C) (W)  
Gr CE sav + AN sav    
    (W)    
V 29a + 43 Undiff wd + Sahel Acacia wooded gr &
  (SW)   (NE) decid bush  
Des VH + M  
      (NE)  
CD 18      
PD 1-10 . 25-100  
  (E) (W)    
T -      
2d SL and 2d MA SENEGAL & MAURITANIA (20,000 km2)
Soils R + B (J) (I)
  (E)   (W)    
Deg E1/W1 + E1    
Gr CE sav        
V 43 Sahel Acacia wooded gr and decid bush
Des H + M    
  (E)   (W)    
CD 8        
PD 1-10   (25-50)    
      on J    
T -        
2m SL and 2m MA SENEGAL and MAURITANIA (20,000 km2)
Soils I + R (J)
  (W)   (E)  
Deg E1 + E1/W1  
Gr CE sav      
V 43 + 29a Sahel Acacia wooded gr and decid bush + undiff wd
  (N)   (S)
Des M + H
      (E)
CD 6    
PD <1 1-10 (10-25)
(W) (E)   on J
T G m    
  (s)    
3m SL and 3m GA SENEGAL and GAMBIA (55,000 km2)
Soils L + R (J)  
Deg E1 E2 + E2 (P1)  
  (E) (W)      
Gr AN sav        
V 29a Undiff wd        
Des M + L + VH
  (NE) (S) (NW)    
CD 18 to 6      
  (C & W) (E)      
PD 1-10 10-50 (50-100)    
  (NE) (C) (NW)    
    incl J      
T Gm Gp Gl    
  (S&E) (S) (S)    
4m SL and 4m GA SENEGAL and GAMBIA (25,000 km2)
Soils N     (J)  
Deg E2   (S3/C1 and S2)    
    coast      
Gr AN sav + Hsav    
  (N)   (S)    
V 11a + 29a (77) (Mosaic of lowland rain forest and sec gr and undiff wd coast (mangrove)
      (NE) on J  
Des L        
CD 18 (None in SW)      
PD 10-25 25-50      
  (C) (N&S)      
T GmGp G1      
  Widespread (S)      
5m MI and 5m SL MALI and SENEGAL (45,000 km2)
Soil I + I/L
Deg E2
Gr AN sav
V 29a + 27 Undiff wd + Sudanian wd with abundant Isoberlinia
(SE)
Des L
CD 5
PD 1-10 + 10-25
(W) (E)
T Gm Gp Gt Gl
widespread (SE)
6m MI and 6m SL MALI and SENEGAL (115,000 km2)
Soils R + L (I)
Deg E1/W1 (E2.E3)
Gr AN sav
V 29a Undiff wd
Des M L
(NE) (SW)
CD 5 0 inNP
(E)
PD 1-10
T Gm Gp
(S)
7d MI and 7d MA MALI and MAURITANIA (90,000 km2)
Soils Q + I
Deg W1 + R
Gr CE sav
V 43 + 29a Sahel Acacia wooded gr & decid bush + undiff wd
(S)
Des M + H
(W & E)
CD 6
PD 1-10 + <1 + 10-50
(on I) (W Mali)
T -
8d MI MALI (55,000 km2)
Soils L + V
Deg E1/W1    
Gr CE sav AN sav  
  (N) (S)  
V 29a Undiff wd  
Des M    
Cd 7    
PD 1-10    
T -    
8m MI MALI (70,000 km2)
Soils L
Degl E1/W1
Gr AN sav
V 29a + 27 Undiff wd + Sudanian wd, with abundant Isoberlinia
(N) (S)
Des M + L
(NE) (SW)
CD 7
PD 10-25
T Gp Gt Gm
widespread
9d*MI (Inland delta of Niger) MALI (25,000 km2)  
Soils G        
Deg P1 . W1/P1    
  (W) (E)      
Gr US + AN sav + CE sav
  (E) (S)   (NW)  
V 64 + 29a Mosaic edaphic gr & semi aqu veg + undiff wd
    (SW)    
Des M      
CD 8 (none in centre)      
PD 1-10 + 25-50  
  (N) (SW)    
T Gt      
  (S)      
10d*MI and 10d BO MALI and BURKINA FASO (55,000 km2)  
Soils Q . R (I)
Deg W2 + E2  
Gr AN sav CE sav    
  (SW) (NE)    
V 43 29a Sahel Acacia wooded gr & decid bush + undiff wd
  (N) (S)    
Des VH + M  
(N&S) (C)        
CD 12 (more in N)    
PD 1-10 + 25-50  
    (C)    
T -      
11m BO BURKINA FASO (70,000 km2)
Soils L            
Deg E2/W1 . E2 + P1 + E1/W1
          (W)   (E)
Gr AN sav            
V 29a   Undiff wd        
Des VH.   L        
  (N)   (S)        
CD 15            
PD 25-50 .     1-25   (50-100)
  (E)   (W)   C (Ougadougou CSZ)
T Gt   Gp   Gm    
  widespread   (W)   (W&S)    
12m*BO and 12m NR BURKINA FASO and NIGER (90,000 km2)
Soils R    
Deg E1/W1 + E2/W1
      (SW)
Gr AN sav + CE sav
      (N)
V 29a Undiff wd  
Des VH + M
  (N)    
CD 16 6 OinNP
  (BO) (NR) (SE)
PD 10-50 + 1-10 (50-100)
    (EC) (W)
T Gt Gp Gm
  (S) (SW) (SW)
13d BO and 13d NR BURKINA FASO and NIGER (20,000 km2)
Soils B . W
Deg S2/W2    
Gr CE    
V 43 Sahel Acacia wooded gr and decid bush  
Des M    
Cd 15 (less in Niger)  
PD 1-10    
T -    
14m BO 14m BN and 14m NA BURKINA FASO, BENIN and NIGERIA (55,000 km2)
Soils L (I) (J)  
Deg E1/C1/B1 (E3) (P1)  
Gr AN sav      
V 27 + 29a Sudanian wd with abundant Isoberlinia
  (E) (W) + undiff wd  
Des L (VH)    
    N of BO    
CD 20 + 16 0 in NP
  NA   W BO E BO and N BN
      S BN  
PD 1-10 + <1 (10-25)
      (SE) W BO
T Gt Gm Gp (E)
  widespread  
15d*NR and 15d *NA NIGER and NIGERIA (35,000 km2)
Soils Q        
Deg W2/E1/P1 . W2 + E1/W1
    (N)     (S)
Gr AN sav + CE sav    
      (N)    
V 29a Undiff wd      
Des H        
CD 5 + 17    
  (NR)   (NA)    
PD 10-25 + 25-50    
T Gt        
  (SW)        
16m*NA and 16m*BN NIGERIA and BENIN (45,000 km2)
Soils L . R + Q (J) (G) (I)
  (W)          
Deg E1/W1 . W1 + W2/E1(S3)(S3)  
Gr   AN sav        
V 29a + 27 Undiff wd + Sudanian wd with abundant Isoberlinia
      (S)      
Des L          
CD 22 - 15   O  
  (NA)   (E BN)   (NP)(W BN)  
PD 1-25 + 25-50 + 50-200  
          (Sokoto CSZ)  
T Gt Gm Gp      
  (SW) (S)      
17d*NR and 17d*NA NIGER and NIGERIA (55,000 km2)
(Sokoto CSZ in S)
Soils Q (G)
Deg W3 (S3)
Gr AN sav . CE sav
(SW) (NE)
V 43 . 29a Sahel Acacia wooded gr & decid bush undiff wd
(S)
Des VH
CD 5 less in N + 19
(NR) (NA)
PD 1-10 . 10-50
(N) (S)
T -
18m*NA NIGERIA     (35,000 km2)
Soils Q . R + L (I)
Deg W2/E1          
Gr AN sav          
V 29a 30 Undiff wd Sudanian undiff wd with islands of Isoberlinia
    (C)        
Des L + VH      
      (N)      
  CD 24        
PD 50-200 + 25-50 + 1-10  
  (E)       (W)  
  Kano CSZ and along Sokoto R      
T Gm?          
  (E)          
19d NR and 19d NA NIGER and NIGERIA (55,000 km2)
Soils Q + J (G)
Deg W3/E1 S3/W2 . S3/W3
Gr CE sav
V 43 + 29a Sahel Acacia wooded gr & decid bush + undiff wd
(SW)
Des VH . H
(SW) (NE)
CD 6 + 22
(NR) (NA)
PD 1-10 10-50
(N) (S)
T Gm?
(SE)
19m*NA NIGERIA (Kano CSZ) (25,000 km2)
Soils Q + J  
Deg W3/E1 . W3 + S3/W2
      (W)  
Gr CE sav + AN sav
  (E)   (W)  
V 29a   Undiff wd
Des VH + L  
      (S)  
CD 19      
PD 25-50 + 50-200  
  (NE)   (SW)  
T Gm?      
  (E)      
20d NA   NIGERIA (25,000 km2)
Soils Q (J)  
Deg E2/W3 + E2/W2
  (E)   (W)
Gr CE sav    
V 29a. 43 Undiff wd Sahel Acacia wooded gr & decid bush
  (S)   (N)
Des H + VH