Government of Uganda prepared research document which is "National Biomass Study on Class of land cover and land use in Uganda is as follows;

Transcription

1 State of baselines Government of Uganda prepared research document which is "National Biomass Study on Class of land cover and land use in Uganda is as follows; Table 3-1 Stratification System Class Land cover and Land use 1. Plantations and woodlots deciduous trees/broadleaves ( hardwood ) 2. Plantations and woodlots coniferous trees 3. Tropical High Forest (THF) normally Stocked 4. Tropical High Forest (THF) depleted/encroached 5. Woodland trees and shrubs (average height >4 m) 6. Bushland bush, thickets, scrub (average height <4 m) 7. Grassland rangelands, pastureland, open Savannah; May include scattered trees shrubs, scrubs and thickets. 8. Wetlands wetland vegetation; swamp areas, papyrus and other sedges 9. Subsistence farmland mixed farmland, small holdings in use or recently used, with or without trees. 10. Uniform commercial farmland mono-cropped, non-seasonal farmland usually without any trees for example tea and sugar estates 11. Build up area Urban or rural built up areas Note: A stratification system in practice is not only for the assessment of biomass but is to a large extent a multipurpose classification system. The great majority of users are not specifically interested in biomass or wood fuel alone, but rather in a wide range of spatial and non-spatial data and information related to land use, land degradation, environment, urban and rural economic developments. 1

2 Plantations (Classes 1 and 2) These are man-made tree plantations comprising of two main classes. Class 1 consists of broad-leaved trees mainly Eucalyptus spp., (Figure 3-1), Maesopsis eminii, Acacia mearnsii (Black Wattle) and some Markhamia lutea. Class 2 includes the Conifers; Pine spp. and Cypress spp. (Figure 3-2) Figure 3-1 Eucalyptus Plantation in Namanve Forest Reserve Figure 3-2 Coniferous Plantation: Katugo Forest Reserve 2

3 Figure 3-3 Tropical High Forest (normally stocked): Mabira Forest Reserve Tropical High Forest (THF) (Classes 3 and 4) These are natural forests rich in species biodiversity i.e. flora and fauna. THF were grouped into Class 3 (Figure 3-3) i.e. normally stocked forest, for example Mabira Forest along Kampala-Jinja Highway, and, Class 4 (Figure 3-4) i.e. depleted or encroached with reduced species richness and composition dominated by secondary growth of bush and shurubs, in particular Solanum gigantea. Figure 3-4 Depleted or encroached Tropical High Forest: Mabira Forese Reserve 3

4 Woodlands (Class 5) Wooded areas where trees and shrubs are predominant. There are wet and dry types. The wet type occurrs as a zone along wetlands (riverine forest) and the dry type is found on grass-covered upland areas. To qualify as woodland the average height of the trees must exceed 4 m. Figure 3-5 Woodland (trees and shrubs): Nakasongola District Bushlands (Class 6) refers to vegetation dominated by bush, scrub and thicket growing together as an entity, but not exceeding an average height of 4 m (Figure 3-6). Figure 3-6 Bushland (bush, thickets and scrubs): Nakasongola District 4

5 It is common to find bushlands in abandoned farmland under late fallow, or forestland. The vegetation rapidly progresses to bush with many different pioneer species as the first phase of succession. In dry, grass-covered areas they appear to be permanent, for example normally taller growing species Acacia hockii in Mbarara and Commiphora africana in Moroto. Common bushlands species include: Securinega virosa, Acanthus pubescens, Lantana camara, Rhus natalensis, Rhus vulgaris, Harisonia spp., Acacia gourmensii, Solanum spp., Ziziphus africana, Xymenia americana, Securidaca longipendiculata, Dovylis macrocalyx (Wild Kei apple), Maytenus senegalensis, Maesa lanceolata and Alchomea cordifolia. Common grass often found within bushlands are : Cloris spp., Panicum spp, Imperata cylindricum (Spear grass) and Hyparrhenia ruffa. Grasslands (Class 7) Rangelands, grazing grounds, improved pastures and natural savannah grassland. Various trees bush/woody vegetation frequently occur on this land, but grass dominates the landscape (Figure 3-7). Figure 3-7 Grassland/Rangelands: Bare hills of Mbarara District Grasslands normally have some trees, but many areas cleared for pasture were devoid of trees and therefore had little woody biomass. Under the circumstances, a sub-qualifier i was introduced in class 7 (grassland) to represent Improved Pasture. 5

6 Wetlands (Class 8) comprises of a) permanent wetland usually with papyrus and reeds (Figure 3-8) and b) seasonally flooded areas. Figure 3-8 Papyrus wetland: Mpologoma River along Iganga-Tirinyi road Wetlands are found along lakeshores and in valleys with impeded drainage. Various vegetation types may occur although grass tends to be the most frequent and dominant species. Common trees include Acacia siberiana and palms such as Phoenix reclinata. Farmland Area (Class 9) Scattered trees are frequently found in the vicinity of the homestaeads. Examples include fruit trees and various multipurpose trees integrated in the farming system (agroforestry), (Figure 3-9). Farmland areas including small holder subsistence farm units covere 50-90% of the land cover of Uganda. The cropping systems include mono- and mixed cropping. Figure 3-9 Subsistence farmland near Mwiri SSS in Jinja District 6

7 Large scale or Commercial farmlands (Class 10) Sugar Estates, (Figure 3-10), tea estates for instance in Western Uganda and Coffee Estates in Central Uganda. Figure 3-10 Large-scale commercial farmland: Kakira sugar estates Built up area (Class 11) Urban areas, towns, village trading centres, quarries, homesteads, school compounds, roads, and recreational grounds. However, urban areas were most common and considerable biomass was noted in various compounds (Figure 3-11). Figure 3-11 Built up area: Kampala City Centre Open Water (Class 12) Lakes, Rivers and Ponds (Figure 3-12). The distinction between open water and flooded wetland is sometimes difficult to draw especially in situations where for instance floating vegetation such as water hyacinth blurs their boundaries. 7

8 Figure 3-12 Open water body: View of L. Victoria from Mwiri SSS Impediments (Class 13) Bare rocks and soils without vegetation cover (Figure 3-13). Figure 3-13 Impediments: Bare rock near Bukedea Trading Centre 8