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parts of the image. The bright yellowish areas have 
high reflectance in all wave-lengths. These are areas of 
open pasture and grassland, bare soil, overgrazed, just 
harvested, roads or built-up areas. Patches of dark red 
represent trees or scrub vegetation. In agricultural 
lands, the bright tones are an indication of cleared or 
fallow fields at this time of the year in January. The 
greenish tones are ploughed fields. Water bodies like 
lake Nakuru, Lake Elmentaita, Lake Bogoria and 
Sasumua dam are indicated in black tones. Lake 
Baringo appears as bright green because of high 
sedimentation. At the middle of Lake Nakuru, the 
bright red indicates aquatic vegetation. Woodlands in 
the image appear as red mottled tones. 
Landsat TM (July 1989) 
Land use cover change was detected on the image 
after analyzing it and comparing the results with the 
photograph of 1969. The colour key shows a 
significant change of land use from the dominant 
forest and large scale farms seen on the photograph. It 
can be seen from figure 8 that the forest which was at 
the confluence of the little shuru and enjoro has been 
cleared. The blue patches within the forest indicate 
new-clear lands now under subsistence cultivation. 
Configuration and Composition of Land cover/Land 
Use 
It was ascertained through remote sensing and time 
series analysis that there has been a significant land 
use cover change, particularly the conversion of forest 
and woodlands to arable land as shown in table 2 and 
figures 1 and 2. The air photographs of 1969 showed 
large scale farming, forest conservation and little built- 
up lands. The pre-change geo-topes of planted forests 
and farms showed clear corridors, sizes, shapes and 
connectivity. The dominant land use cover types were 
forests (75%), woodlands (12%) and farms (13%). By 
140 
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Zia | 
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Figure 1: Change in woodland 
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004 
1989, the landscape had changed tremendously as 
showed by the landsat sub-scene image which showed 
60 % forest and woodland and 40 % agriculture and 
built-up area. The dominance of mixed agriculture and 
subsistence farming in much of the former Nessuiet 
forestlands and Ngondu large scale farm is shown by 
the different shades of blue and whitish patches. Due 
to decrease of spatial resolution on the images, the 
dominant land use cover types of forest and mixed 
farming exhibit a rapid increase and overestimation at 
the coarse levels of spatial aggregation at the expense 
of non-dominant land use cover types like rural built- 
up lands. The dominant land use cover types are 
overestimated due to spatial mixing of covers hence 
the high variances. Settlements like Ngondu and 
Njokerio now stand on former large scale farms and 
grasslands. Ngondu formerly known as Wright farm 
produced wheat and dairy products while Njokerio 
formarly Sebiens farm for horses and flower 
production. Forest lands in Beeston area have been 
converted into arable and built-up lands. Expansion 
into forest and riverine areas has been taking place for 
quite a while now. From ground survey of 2003, the 
dominant land cover types were 5% forest, 7% 
woodland, 82% agriculture and 6% built-up area. It 
was evident that loss of forest cover in the reserves 
was by both clear cut and progressive thinning due to 
poaching by local residents. There are many small 
land use patches of maize, beans, potatoes, wheat, 
pasture and homesteads with spectrally similar land 
cover which tend to clump to the bigger entities 
contaminated by mixed pixels in remotely sensed data. 
The EU-LUCAES method used for this study provided 
a simple calibration which has been validated to assist 
with interpreting images to determine land use cover 
types of heterogeneous type, especially subsistence 
agriculture and rural built-up land on former forests 
Woodland per segment/Imagette 
   
and large scale farms. 
NS Q 
qe Q9 RTS SAN à > 0 oy 
Segments 
22003 mM 1989 [11969 
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