صغد
Cotton and wheat are the two main cash crops in Tajikistan, cultivated on nearly 70% of the cropped area (30% under cotton, 36% under wheat, 9% under other cereals). Cotton fiber is Tajikistan's leading agricultural export commodity, contributing 16% of total exports (it is second only to aluminium, which accounts for a staggering 60% of the country's exports). Cotton requires high temperatures and intensive irrigation, and it is primarily grown in hot river valleys: the Ferghana Valley on the Syr Darya in Northern Tajikistan (Sughd Province), the Lower Kofarnihon and Vakhsh valleys in south-western Khatlon, Kyzylsu and Panj valleys in south-eastern Khatlon, and Gissar Valley stretching west of Dushanbe to the border with Uzbekistan around the middle course of Kofarnihon River. Khatlon Province is the main cotton growing area in Tajikistan, contributing 60% of the cotton harvest; Ferghana Valley in the north of Sughd Province contributes 30% and Gissar Valley (in the Region of Republican Subordination) another 10%. The Tajik part of Zeravshan Valley in the south of Sughd Province is too cold for cotton, which grows only further west in the Uzbek part of the valley near Bukhara. The intensive irrigation of cotton in Tajikistan's valleys reduces the flow in the two large rivers feeding the Aral Sea: the Syr Darya in the Ferghana Valley in the north and the Amu Darya along the southern border with Afghanistan, which in turn relies on its tributaries Kofarnihon, Vakhsh, and Kyzylsu rivers. The "white gold" of Tajikistan, as well as Turkmenistan and Uzbekistan, may well have contributed to the catastrophic drying of the Aral Sea during the Soviet times and thereafter.