Impact of climate change and anthropogenic pressures on degradation and loss of wetlands in two ago-ecological zones of Lesotho

There is sparse information on the wetlands of Lesotho in terms of their characteristics, climate change impacts, management and coverage and there is a growing concern on high levels of degradation observed in these ecosystems. Thus the main objective of this investigation was to assess the current status of two wetlands in two agro-ecological zones (AEZs) of Lesotho in terms of their soil physico-chemical characteristics and to suggest plausible management strategies that can be used to enhance ecosystem services provided by wetlands in the Kingdom of Lesotho. The study was conducted on two wetlands located separately on two AEZs of Lesotho namely the mountains (Thaba-Putsoa) and the lowlands (T’sakholo). The study involved a thorough analysis of the soil morphological properties and soil physio-chemical properties. The results indicated that soil color varied between black and very dark greylish with sandy-loam texture in Thaba-Putsoa while in T’sakholo soil colour ranged from light-brown to brown and reddish brown with sandy, sandy-clay, slit-loam and clay texture. Soil structure varied between crumb and single –grain with poor drainage observed on both sides. Soil chemical properties such as pH, soil organic carbon (SOC) and soil organic matter (SOM) varied both between and within sites. Other properties such as silt:clay ratios, bulk density (BD), electrical conductivity (EC) were slightly differently between sites with low concentration of base cations and cation exchange capacity (CEC). Rainfall distribution was found to have been highly variable for a 10 year period (1997 – 2007) on both sites with a projected decline for next decade (2007 -2017). Temperature trend showed a decreasing trend for T’sakholo. Maximum temperature was observed to follow the same trend on both sites. The investigation therefore concluded that there is a great heteroginity of soil properties with in wetlands and this heteroginity can have important consequences on wetland biota and biochemistry. Wetlands soils show high levels of degradation and this based on the SOM.silt:clay ratio calculated for each site. Climate change is likely to impart severely on already diminishing wetlands of Lesotho with potentially disastrous consequences on water projects in Lesotho.