Jk. Maingi et Se. Marsh, Assessment of environmental impacts of river basin development on the riverine forests of eastern Kenya using multi-temporal satellite data, INT J REMOT, 22(14), 2001, pp. 2701-2729
The utility of Landsat MSS (Multispectral Scanner) and SPOT XS data in moni
toring the impacts of river basin development on a riverine forest located
in the lower Tana River Basin of eastern Kenya was evaluated. Land cover ch
ange maps derived from Landsat MSS indicated little change in total forest
area between 1975 and 1984. Land cover change maps derived from SPOT XS dat
a indicated a 27% decline in forest area between 1989 and 1996. Mean patch
size and area-perimeter ratio of the closed riverine forest remained virtua
lly unchanged whereas these parameters for the open forest class decreased
by 31% and 4% respectively. In addition, the average extent of the open riv
erine forest from the river channel declined by about 200m between 1989 and
1996. This decline was attributed to decreased extent of floods along the
floodplain following construction of dams in the upper river basin, and inc
reased exploitation of the forests for fuelwood, especially in the vicinity
of the established Bura Irrigation and Settlement Project. The greater lat
eral movement observed in the location of the river channel for the 1975-19
85 period, compared to the 1985-1996 period, was also attributed to constru
ction of dams in the upper river basin.