**5.3 Other effects of grazing**

Grazing of these peatlands by domestic stock (wild horses, cattle, donkeys, goats and sheep) causes trampling of the vegetation that can result in footpaths (Figure 9) and deep hoof prints in the peatlands. These impacted areas can quicly become devoid of vegetation.

Fig. 9. Footpaths, devoid of vegetation, leading to the formation of erosion gullies in the peatlands as a result of trampling by domestic stock.

However, the heavy animals such as horses and cattle trample holes into the vegetation (Figure 10). These hoof prints form larger holes which eventually start to erode. The

Fig. 10. Deep hoof imprints of animals into the peatlands causing erosion in the long term

Grazing of these peatlands by domestic stock (wild horses, cattle, donkeys, goats and sheep) causes trampling of the vegetation that can result in footpaths (Figure 9) and deep hoof prints in the peatlands. These impacted areas can quicly become devoid of vegetation.

Fig. 9. Footpaths, devoid of vegetation, leading to the formation of erosion gullies in the

However, the heavy animals such as horses and cattle trample holes into the vegetation (Figure 10). These hoof prints form larger holes which eventually start to erode. The

Fig. 10. Deep hoof imprints of animals into the peatlands causing erosion in the long term

peatlands as a result of trampling by domestic stock.

**5.3 Other effects of grazing** 

vegetation also dies off due to the high urea-content of the urine of animals (Figure 11), while cow dung covers the vegetation for a significant period of time causing the exclusion of sunlight, which put the affected plants under stress leading to die off of the vegetation with other species establishing (Figure 12).

Fig. 11. Vegetation die-off caused by the high urea content of the urine of domestic stock grazing on the peatlands.

Fig. 12. Cow dung covers the vegetation for a significant period of time also leading to vegetation die-off with other species establishing.

Footpaths (Figure 9) are another major contributor to wetland degradation. On footpaths the animal hooves usually cause destruction of the vegetation cover which in turn results in the formation of large erosion gullies.

Impact of Domestic Animals on Ecosystem Integrity of Lesotho High Altitude Peatlands 265

Due to the low vegetation cover, shallow soils and steep slopes of the valley heads in Lesotho, there is a high water and sediment run off (Figure 15). The peatlands are the only sites where water is being retained and slowly released. These peatlands are very valuable socioecological ecosystems to the highlands of Lesotho because of the goods and services they present. The natural vegetation of these peatlands sustains extensive grazing by domestic livestock. Destruction of these peatlands will have serious implications for the ecosystems and biodiversity of the region. The high runoff sometimes results in the deposition of sediment onto the peatlands. In these instances a sedimentation fan forms on

top of the peatland. Subsequently the covered wetland vegetation dies off.

Fig. 15. Sediment runoff from the surrounding catchment areas onto the peatlands.

richness. A very dense cover remains despite the heavy grazing pressure.

resilience of these systems if properly managed.

All the Lesotho peatlands as well as the surrounding upland slopes are heavily affected by grazing and trampling. Species composition of the slopes has been affected significantly. These slopes are all dominated by unpalatable dwarf shrubs such as *Helichrysum trilineatum, Eumorphia sericea, Chrysocoma ciliata, Euryops decurrens* and the absence of grass species is

The degradation of these peatlands cannot really be attributed to the grazing per se of the wetland species. It has been noted that these mat forming plants especially *Isolepis cernua* has a remarkable tolerance of heavy grazing and the peatlands still maintain high species

The canopy cover of the herbaceous plants of both the Lesotho and near pristine Platberg peatland systems was generally high though the latter had a taller and more diverse structure. The more pristine Platberg peatlands had a lower species richness with a larger grass component than the Lesotho peatland areas. Furthermore the Platberg peatlands had a markedly higher biomass production than the Lesotho peatlands. However the exclosure plots showed a noticible increase in production compared to the grazed plots indicating the

**6. Conclusion** 

notable.

Due to the formation of erosion gullies, lateral drainage from the peat takes place at an alarming rate. Desiccation of the peat takes place along the gully which allows the peat to dry out and becomes eroded. A contributing factor is the trampling of the gully banks as animals drink from the streams. Their hooves loosen the dry peat which drains down to the streams (Figure 13).

Fig. 13. Large erosion gullies in the peatlands as a result of trampling and overgrazing.

The ice rat (*Otomys sloggettii*) (Figure 14) is a natural inhabitant of high-altitude vegetation types including peatlands (Schwaibold, 2005). On an undisturbed peatland these rats' dens, runways and tunnels are limited to the peatland fringes and drier areas. The desiccation of the peatlands results in the encroachment of these rodents onto the drier parts, especially around those areas near erosion gullies. Their tunnels contribute to the erosion and agrivating the desiccation the peat (Figure 13) as well as the alteration of the habitat conditions. This leads to various terrestrial plant species establishing thereby displacing the peatland vegetation.

Fig. 14. The ice rat (*Otomys sloggettii*) (insert) with its tunnels draining the peatlands and causing erosion.
