Long-term climatic data （maximum temperature, minimum temperature, rainfall and evaporation） for Big Bend in the Lowveld, a semi-arid region of Swaziland, were analysed for any changes or variations. Evaporation and...Long-term climatic data （maximum temperature, minimum temperature, rainfall and evaporation） for Big Bend in the Lowveld, a semi-arid region of Swaziland, were analysed for any changes or variations. Evaporation and rainfall data were analysed to assess water resources availability in the region. Analysis of the available data shows that there is no indication of decrease in rainfall with time, but the results show that there has been a steady increase in minimum temperatures over the last 25 years. The average effective water resources index, measured as the difference between mean annual rainfall and mean annual evaporation, for the region in the period from 1965 to 2001 was -1,500 mm. The large negative index implies low available water for the region, a situation that is likely to affect agricultural, hydropower and other water related development activities in the region. The negative effective water index implies deficits in the region＇s water resources which call for better management of the region＇s water resources. In the agriculture sector, this requires promoting technologies and practices that provide for water saving, improved water use performance and high water productivity. These include soil conservation tillage, wastewater reuse, runoff harvesting and soil fertility interventions through application of fertilizers, manures and mulches, and agronomic management. There is need for more analysis for the other regions in order to get a countrywide picture of the climate as well as water resources situations.展开更多
文摘Long-term climatic data （maximum temperature, minimum temperature, rainfall and evaporation） for Big Bend in the Lowveld, a semi-arid region of Swaziland, were analysed for any changes or variations. Evaporation and rainfall data were analysed to assess water resources availability in the region. Analysis of the available data shows that there is no indication of decrease in rainfall with time, but the results show that there has been a steady increase in minimum temperatures over the last 25 years. The average effective water resources index, measured as the difference between mean annual rainfall and mean annual evaporation, for the region in the period from 1965 to 2001 was -1,500 mm. The large negative index implies low available water for the region, a situation that is likely to affect agricultural, hydropower and other water related development activities in the region. The negative effective water index implies deficits in the region＇s water resources which call for better management of the region＇s water resources. In the agriculture sector, this requires promoting technologies and practices that provide for water saving, improved water use performance and high water productivity. These include soil conservation tillage, wastewater reuse, runoff harvesting and soil fertility interventions through application of fertilizers, manures and mulches, and agronomic management. There is need for more analysis for the other regions in order to get a countrywide picture of the climate as well as water resources situations.
