Bemigisha, Jane 
  
water potential risk was manifested all around the shore with medium to high-risk level. The southwest papyrus area was at 
high risk by woodland and tended towards medium in the northern area. 1% of the total papyrus area was found within low 
to medium risk potential, while 99% was within medium to high risk by woodland. Most of the north swamp was at high 
risk being taken over by shrubland and tended towards a medium to high risk on the southwestern area. 
- Medium ium -High 
type ha) |%ge ha) |%ge 
icultural fields 0 1044.9 100 
area 44.1 23 8 77 
water 0 1044.9 100 
oodland 11.3 1 1033.6 99 
0 1044.9 100 
d 0 1044.9 100 
Table 1. Risk of land cover types based on distance to papyrus swamp 
   
   
Criterion (2) : Change in area(ha) of papyrus by each land cover type:For each land cover type, the total area changed 
from or to papyrus, from 1967 to 1995 was calculated. Open water had the highest risk (with a loss of 1023.25 ha of 
papyrus), followed by shrubland (814 ha), agricultural fields (372.25 ha), woodland (256.25 ha), grassland (153 ha), and built 
up showed no effect ( see table 2) . The negative scores indicate the loss of papyrus area, and positive scores a gain. 
/84 change 
to agricultural fields |3.5 373.75 
to open water -1682.25 9 
to woodland -73 183.25 
to shrubland -273 541 
to grassland -160.5 5 
to Built up area 0 
Table 2 Change in area (ha ) of papyrus by other landcover types 
  
Criterion (3): Rate of change of landcover types: It was assumed that the higher the rate of change of a particular land cover 
type, the higher the risk in terms of impact on the present and future papyrus area. In table 2 the rate of change (ha/year) was 
calculated for each of the seven land cover types over the period 1967-1995. Agricultural fields had the highest rate (1292 
ha/yr) , followed by shrubland (58.3 ha /yr), built up area (8.5 ha/yr), open water (-18.8 ha/yr), Woodland (-41.7), and 
Grassland (-42.9 ha/yr). 
3.3.1 Weights for Scenario 1 and 2 : Table 3 shows shrubland with the highest potential risk to the swamp ( 1), 
followed by open water (0.85), agricultural fields (0.74), woodland (0.28), grassland (0.21), and built up (0.17). The results 
were consistent with the following order: Bu » Gra » Wdl » > Ow > Shr 
     
  
change(ha) 
Increase rate (ha/yr) 
t (the higher,linverted coefficient ( 
lower the risk the lower the risk) 
Senario 1 Scenario 2 [Scenario 1 Scenario 2 
1 1 0.17 0.11 
8 0.75 0.21 0.15 
.60 0.5 0.28 0.22 
23 0.14 0.74 0.8 
20 - 0.85 - 
17 0.11 1 1 
Codes: Ag -agricultural field, Ow- open water, Wdl- woodland, Shr- shrubland, Gra- Grassland, Bu -Built up 
Table 3. Weights in terms of risk for land cover types: Scenario 1 and 2 
  
170 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.