Book chapter
Groundwater resources
https://doi.org/10.4324/9780429436475-4
Highlights
- Share of groundwater in total withdrawal: Tajikistan 19.7%, Afghanistan 15%, Turkmenistan 1.1%.
- Total water storage change from GRACE: −3.35 ± 0.45 mm a year.
- Mean annual rainfall: 299 mm (1979–2000) and 333 mm (2002–2017), up 11%.
Keywords
- Aral Sea basin
- groundwater
- GRACE
- irrigation
- salinity
Summary
This chapter reviews groundwater in the Aral Sea basin. Groundwater supplies rural areas, irrigation and some large cities, and its use is growing with farming demand because aquifers need less investment in infrastructure than surface water. Its share of total water withdrawal varies by country: it is highest in Tajikistan (19.7%) and Afghanistan (15%) and lowest in Turkmenistan (1.1%), and across the basin it remains a small part of total use.
Groundwater levels change with the irrigation season. Higher water tables caused by irrigation can raise soil salinity, while falling levels threaten ecosystems and promote desertification. The effects of land-use and climate change on groundwater are poorly understood, and recharge appears to be falling as soils dry.
Because measured groundwater data are scarce, the authors used GRACE satellite data to estimate the change in total water storage. It is falling by 3.35 ± 0.45 mm a year, which they attribute mainly to higher evaporation and groundwater pumping, even though mean annual rainfall rose by 11% between 1979–2000 and 2002–2017. Groundwater quality has worsened in heavily irrigated areas, partly because drainage systems are no longer maintained.
How to cite
Abror Gafurov, Vadim Yapiyev, Mohamed Ahmed, Jay Sagin, Ali Torabi Haghighi, Aigul Akylbekova and Bjørn Kløve (2019). Groundwater resources. In: S. Xenarios, D. Schmidt-Vogt, M. Qadir, B. Janusz-Pawletta, I. Abdullaev (eds), The Aral Sea Basin: Water for Sustainable Development in Central Asia, chapter 4, pp. 39–51. https://doi.org/10.4324/9780429436475-4