4  Natural Environment  
             The natural environment with its particular characteristics is the context in which 
             humanitarian aid has taken on the task of creating the settlement at which the refugees 
             have been settled. Only by taking the initial environmental conditions into consideration 
             can the desired objectives be attained, especially that of food self-sufficiency. 
             The map extracts below show the great diversity found in environmental conditions, 
             between the two reception areas, Rhino Camp and Adjumani, but as much within 
             each. Even though these thematic maps are still very general, they are necessary for 
             forming a first impression of prevailing environmental situations. 
             4.1  Geology and Relief 
             A fault network crosses the North of Uganda, separating it into two geological units. 
             There is the central rift with its Pleistocene sediments, then the granite-gneiss 
             basement uplifted in the West and in the East.  
                             Geology Topography 
             Sources : Department of Lands and Surveys : (1962) : Atlas of Uganda. First Edition. Geology. Entebbe. Aster digital terrain 
                    model. Database IRD/UNHCR FRAME. 
             Figure 23:  Geology and topography in the North of Uganda. 
             The two refugee settlements are located in different geological units. Rhino Camp is 
             situated entirely in the graben. The elevation varies in that area between 600 and 800 
             metres. On either side of the rift, the elevation rises sharply to over 900 metres on the 
             East and to 1100 metres on the West. The Adjumani District is on the granite-gneiss 
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             basement raised up in the East. Elevation in the district varies by 750 metres, going 
             from 610 metres, along the Nile in the North, to 1370 metres at the point culminating in 
             the South-East of the district.  
             4.2 Soils 
             The map below shows the major soil-type distribution in the North of Uganda. Rhino 
             Camp characteristically has Ferrisols and Vertisols. In the Adjumani Dstrict tropical 
             ferruginous soils are found. The geology and topography are determining factors for 
             soil types and partly explain the presence of soils of that nature in the two areas. 
             Soils  
                                                                         
             Sources :  Department of Lands and Surveys : (1962) : Atlas of Uganda. First Edition. Soils. Entebbe. IRD/UNHCR FRAME 
                    database. 
             Figure 24:  Major soil types in the North of Uganda.  
             This map at the initial scale of 1 :1 500 000 shows to advantage the existence of 
             different types of soil in the two refugee reception zones. However, it does not present 
             all the diversity. IRD has thus analysed 72 soil samples from Rhino Camp and 
             Adjumani. Such soil analyses are essential in the context of refugee settlements. They 
             should be conducted before settlements are set up. 
             4.3 Climate 
             There is no weather station which records temperatures and rainfall in the two areas 
             studied. The nearest station is at Moyo but it is not representative of the climatic 
             conditions prevailing at Rhino Camp and Adjumani. Just one general map of average 
             annual rainfall at Rhino Camp and Adjumani is available. It indicates that annual 
             average precipitation in the Adjumani District is around 900 mm in the North-East and 
             South of the district and that it rises towards the central part to 1200 mm. The values at 
             Rhino Camp are comparable. 
             There are therefore in the two zones some sharp inequalities in the distribution of 
             annual rainfall. However, the cartographic information is not sufficient. The North of 
             Uganda is characterised by pronounced seasons. There is a rainy season with two 
             maxima and a dry season of around 3 months, from December to March. Beyond this 
             it is essentially the unpredictability and the rainfall variability which cause problems for 
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             agriculture in this region. Rainfall variations on the monthly, diurnal or seasonal time-
             scales restrict farming activities in the two refugee settlement zones. Only daily rainfall 
             and temperature readings at representative observation points would aid 
             understanding of the climatic conditions there. Such information is indispensable. 
                      Mean annual rainfall                             
                                                                     
             Sources :   Department of Lands and Surveys : (1962) : Atlas of Uganda. First Edition. Mean annual rainfalls. Entebbe. 
                    IRD/UNHCR base de données FRAME. 
             Figure 25:  Mean annual rainfall in the North of Uganda. 
             4.4 Vegetation 
             A vegetation map produced during the 1960s shows that the two areas were at the 
             time covered mainly by wooded savanna. This category itself includes many 
             vegetational formations with a more or less developed tree layer. On the map, it is 
             subdivided according to the dominance of one or more species. Within the category 
             plant associations are separated: Butyrospermum savanna, Combretum savanna, 
             mixed savanna, and dry Acacia savanna. All these sub-types have been associated 
             with Hyparrhenia spp. Two other plant formations complement this mosaic of different 
             savannas as it existed in the 1960s: a marshy zone along the River Nile covered with 
             papyrus (Cyperus papyrus) and an isolated semi-deciduous forest situated in the 
             South-East of the Adjumani District, with dominant Celtis-Cynometra. 
             The 1 : 1 500 000 scale map carries little detail. Developments in remote sensing now 
             offer satellite images as means of defining the state of the Earth’s surface. In the future 
             it would be preferable to use a satellite image before settlement installation in order to 
             draw up a land use map. This basic information would certainly help considerably in 
             the site planning phase. It would first make possible an assessment of the load 
             capacity of each area set aside for refugee reception. It would also provide information 
             necessary for adapting settlements to local conditions and avoiding environmental 
             degradation right from the start. Images obtained subsequently at regular intervals 
             would allow monitoring of land-use changes with time, and identification of 
             environmental problems in order better to adjust the assistance programmes offered 
             for the refugees. 
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          Vegetation 
          Sources :   Department of Lands and Surveys : (1962) : Atlas of Uganda. First Edition. Vegetation. Entebbe. IRD/UNHCR base de 
               données FRAME. 
          Figure 26:   Vegetation types in the North of Uganda. 
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