Astragalus centralis: The Tamditau Milkvetch evaluated as Critically Endangered.

Milkvetches, Astragalus spp., are leguminous herbs of or shrubs, predominantly found in arid or semi-arid climates around the Northern Hemisphere. They are a large group of Plants, with 3082 species recognised in 2025, this is largely because many species are highly endemic (i.e. have very limited ranges). Such limited ranges can make species extremely vulnerable to extinction, though to date only 149 species of Astragalus have been formerly assessed to determine their status under the terms of the International Union for Conservation of Nature's Red List of Threatened Species, with 36% of these being determined to be threatened, and one, the Tallante's Milkvetch, Astragalus nitidiflorus, has been found to be extinct in the wild.

Thirty two species of Astragalus have been recorded in Uzbekistan, more than any other genus in the country. Most of these are found within the low mountain ranges of the Kyzylkum Desert, a notable centre of Plant endemism covering parts of Uzbekistan, Kazakhstan, and Turkmenistan. Within this desert a series of low mountain ranges (typically lower than 1000 m) form a western extension of the Central Asian Mountain Belt, creating a range of distinctive micro-habitats. promoting Plant endemism. Of the forty two species of Astragalus known from this region, six are thought to be entirely endemic. 

In a paper published in the journal Orynx on 18 February 2026, Bekhruz Khabibullaev, Khabibullo Shomurodov, and Natalya Beshko of the Institute of Botany of the Academy of Sciences of the Republic of Uzbekistan, and Giuseppe Fenu of the Department of Life and Environmental Sciences at the University of Cagliari, formally assess the conservation status of Astragalus centralis, referred to here as the Tamditau Milkvetch, an endemic species from the Kyzylkum Desert of Uzbekistan. 

The Tamditau Milkvetch is a perennial herbaceous Plant reaching about 15 cm in height, with stems covered in white hairs, paired leaves, and dense inflorescences of yellow flowers. It was formerly thought to be present in the Tamditau, Kuldzhuktau, and Auminzatau mountain ranges within the Kyzylkum Desert. However, a previous study, published in 2016, established that the populations in the Kuldzhuktau and Auminzatau mountains were in fact a separate species, which was described as Astragalus kuldzhuktauense. 

As a result of this, the known occurence of Astragalus centralis shrank to a single population in the Tamditau Mountains, prompting monitoring and censuses of the species in 2016-17, 2018-19, and 2023-24, each time assessing the number of Plants present at the peak of the flowering season.

The Tamditau Milkvetch grows on northern slopes in the Tamditau Mountains, in crevices between large boulders in gravelly and rocky limestone soils. All known members of the species are found within an area of 60 000 m². During the 2016-17 season, about 1000 Plants were recorded, but in 2018-19 this had fallen to about 600 individuals, within an increased proportion of older Plants (80% against 50% in 2016-17. In 2023-24 only 491 Plants were recorded, with 90% of these being mature.

The mountains of the Kyzylkum Desert, Uzbekistan, showing the distribution of Astragalus centralis on the northern slope of the Tamditau (Aktau) mountains. Khabibullaev et al. (2026).

The species appears to be facing a number of immediate threats. Limestone is extracted in the region, and new excavation trenches are both present and increasing in number within the range of the Tamditau Milkvetch. The population is also located close to a settlement which primarily derives its income from livestock herding, with the area where the species grows being used as a year-round pasture. Climate change appears to be making the area more arid, and Insects have been observed to consume more of the species seeds in dryer years. This drying climate is also associated with more frequent and intense spring flash floods, which can destroy younger Plants with less well established root systems. The species is also vulnerable to short-term cold anticyclones, which occur in the area every 5-6 years.

Characteristic habitat of Astragalus centralis, endemic to the Tamditau (Aktau) mountains. Khabibullo Shomurodov in Khabibullaev et al. (2026).

Based upon this, Khabibullaev et al. suggest that the Tamditau Milkvetch is becoming unable to sustain its only population, due to a low and decreasing survival rate for young Plants. For this reason they recommend that the species be classified as Critically Endangered under the terms of the International Union for Conservation of Nature's Red List of Threatened Species. 

The Tamditau Milkvetch in its habitat. Khabibullo Shomurodov in Khabibullaev et al. (2026).

Based upon this, Khabibullaev et al. recommend a series of steps to be taken in order to protect the future of the Tamditau Milkvetch. 

Firstly, the species habitat should be designated a protected area. This would not just protect this species, but also other species found in the area which have been identified as at risk, including the Kyzylkum Giant Fennel, Ferula kyzylkumica, the Aktavi Stickseed, Lappula aktaviensis, The Kyzylkum Peppergrass, Lepidium subcordatum, the Hairy Catchfly, Silene tomentella, and the Aktau Needlegrass, Stipa aktauensis. They further recommend that the Tamditau Mountains should be considered to be a significant national ecosystem, and assessed for potential inclusion on the nternational Union for Conservation of Nature's Red List of Ecosystems.

Detail of the inflorescence of the Tamditau Milkvetch, Astragalus centralis. Khabibullo Shomurodov in Khabibullaev et al. (2026).

Secondly, they recommend that an inventory of pasture resources in the region is carried out, in order to determine the sustainable grazing capacity of the area, and develop a better plan for livestock management.

Thirdly, they suggest a translocation strategy for the species, moving individual Plants to other areas identified as suitable for its survival.

Fourthly, they suggest that a cultivated population be established at the Kyzylkum Desert Experimental Station, and seeds of the species be gathered and placed in an appropriate seed bank.

Finally, they suggest that the species be included on the International Union for Conservation of Nature's Red List of Threatened Species, and an awareness campaign for the species be used to promote its conservation.

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Four dead, over 100 000 displaced, following dam failure in Uzbekistan.

Four people have died, more than 60 have been hospitalised, and over 100 000 have been forced to flee their homes following the failure of a dam in Uzbekistan. Part of the 29 m high Sardoba Dam in the Sirdaryo Region gave way abruptly at about 6.00 am local time on Friday 1 May 2020, sending a torrent of water through villages and agricultural land downstream. Around 70 000 people were forced to flee homes in  22 villages in Uzbekistan as a result of the incident, with another 31 600 being forced to flee from 14 villages in neighbouring Kazakhstan, with extensive scouring and loss of topsoil in agricultural areas occurring in both countries.

Flooding in the Maktaaral District of Kazakhstan following a dam collapse in neighbouring Uzbekistan on 1 May 2020. Prime Minister of Kazakhstan/The Astana Times.

The Sardoba Dam was completed in 2017 following seven years of construction work, and impounded 922 million cubic metres of water from the Sardoba River for agricultural irrigation in the Sirdaryo and Jizzakh regions of Uzbekistan. The cause of the dam failure is unclear, though authorities in Uzbekistan are investigating the possibility of negligence during construction being a contributing factor. 

Landsat 8 image of the Sardoba Reservoir in Uzbekistan (bottom of image) and a new lake created by the pooling of the released water (top of image). The section of dam that failed is on the left side. Note the scouring of the land between the reservoir and the new lake. Earth Observatory/NASA.

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Landslide kills six on construction site in Tashkent, Uzbekistan.

Six workers were killed in a landslide at a construction site in Tashkent, the capital of Uzbekistan on Wednesday 18 December 2019. The workers are understood to have been working on a new metro line when part of an embankment collapsed onto them following heavy rain. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. Construction sites can be particularly prone to such events, as they expose layers of sediment usually covered by other material, often on steep slopes which are more prone to collapse, for which reason it is important to keep all such surfaces properly shored up. The cause of the Tashkent landslip is not yet clear.

 Landslip at a construction site in Tashkent, Uzbekistan, on 18 December 2019. Radio Free Europe.

Tashkent has a dry climate, typically receiving less than 450 mm of rain in a year; the winter period, from December to April is cooler and wetter than the rest of the year, with rain tending to exceed 50 mm per month, but much of this typically falls as snow, This year the weather has been both warmer and wetter than is typical, with heavy rains falling on the city, which may have caused problems for construction workers unused to such conditions.

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Collapse at gold mine in Uzbekistan kills at least one.

At least one person has died and around 20 more are thought to be trapped below ground following a collapse at an abandoned gold mine in the Paxtachi District of Samarkand Province in Uzbekistan on Tuesday 16 January 2018. The incident was not reported to the authorities until Friday 19 January, as the miners were working illegally in the disused mine, and initial rescue attempts were carried out by local communities without involving any official body.

The approximate location of the 16 January 2018 Samarakand mine collapse. Google Maps.

Uzbekistan has significant deposits of a range of precious and base metals, and is the world's twelth largest producer of gold. However the country also has a very high unemployment rate, and disused mines can provide a potential source of income in areas where mining has ceased. Such unregulated mining seldom featuring any form of heath and safety procedures, and accidents are frequent.

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Magnitude 5.0 Earthquake in the Jizzax Region of Uzbeckistan.

The United States Geological Survey recorded a Magnitude 5.0 Earthquake at a depth of 20.0 km in the Jizzakh Region of Uzbeckistan, close to the border with Tajikistan, slightly before 6.50 pm local time (slightly before 1.50 pm GMT) on Friday 29 September 2017. There are no reports of any damage ot casualties associated with this event, but it was felt in Tashkent and Dushanbe.

The approximate location of the 29 September 2017 Jizzakh Earthquake. USGS.

The Jizzakh Region lies to the north of the boundary between the Indian and Eurasian tectonic plates, which runs through northern Afghanistan. The Indian Plate is moving northward relative to the Eurasian Plate, causing folding and uplift along this boundary, which has led to the formation of the Hindu Kush Mountains of Afghanistan, The Pamirs in Tajikistan, the Himalayas and the other mountain ranges of Central Asia., and which makes the nations in this boundary zone prone to Earthquakes.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.

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Earthquake on the Kyrgyzstan/Uzbekistan Border, 20 July 2011; at least 14 people dead.

Slightly after 1.30 am local time on the 20th July 2011 (or slightly after 7.30 pm on the 19th July GMT) an earthquake stuck in the Fergana Valley on the Kyrgyzstan/Uzbekistan border. It had a magnitude of 6.1 on the Richter Scale, and was at a depth of 16 km; shallow enough to have a considerable effect at the surface. Although the epicenter was on the Kyrgyrzstan side of the border, the majority of the damage seems to have occurred on the more densely populated Uzbek side of the border.

The geology of the area is complex; the Pamir Mountains to the southeast are being forced north into the Kazakh Shield to the northeast by the northward movement of India, far to the south. This causes shear in the Fergana Basin, as the rocks are twisted anti-clockwise, leading to thrust and strike-slip faulting. A thrust fault occurs where rocks are forced up and over one another; in this instance the faulting would be a blind-thrust; a thrust that happens beneath the surface, causing notable effects (e.g. earthquakes) but not visible faulting at the surface. A strike-slip fault occurs where two sections of rock slide past one-another. The earthquake in the Fergana Valley is likely to have been a combination of the two.

No fatalities were reported in Kyrgyrzstan, though 15 people were injured. Between 200 and 600 houses were damaged or destroyed in Batken Province (where the earthquake occurred) and (neighboring) Osh Province.

A single fatality was reported in Tajikstan, though this was caused by somebody jumping out of a window in panic, rather than directly by the earthquake. There are also reports of fractures to a dam under construction, delaying work while engineers investigate the situation.

Across the border in Uzbekistan the situation it much more serious (and confused). The city of Fergana (sometimes Ferghana or Farghona), capital of Fergana Province, with a population of 214 000, lies just 42 km from the epicenter of the quake (the point at ground level directly above the centre of the quake). For several hours the Uzbek authorities denied that anything had happened at all. It now appears that at least 13 people have been killed, and 86 injured, 35 requiring hospital treatment. At least 800 buildings have been destroyed, including several deemed to be of historic significance. It is likely that there will be further reports of injuries and possibly deaths as much of the population lives in remote villages in the mountainous region, and few buildings are earthquake proofed in any way.

There have been three other major earthquakes in the vicinity within the last 40 years, though none of these have caused any reported fatalities, though the wider region has suffered a number of significant quakes.

A series of earthquakes in 2006/2007/2008 destroyed a large number of buildings in Osh Province, displaced several thousand people and caused many fatalities. The worst of these, in October 2008, caused 15 fatalities (including 41 children), and destroyed the towns of Nura and Kura. This earthquake also caused damage in the Xingjiang Uyghur Autonomous Region of China.

In July 2006 a pair of magnitude 4.5 earthquakes in the Khatlon region of Tajikistan killed three people and injured 19 more. It also destroyed several thousand (non-earthquake-proofed) houses and caused a collapse in infrastructure that lead to a malaria epidemic, amongst other problems.

In 1985 a magnitude 7.4 earthquake in Wuquia County, Xingjiang, China, that was felt across the Fergana Basin and as far away as Pakistan. 65 deaths were reported.

In April 1966 a 7.5 magnitude earthquake destroyed Tashkent, the capital of Uzbekistan, making about 300 000 people homeless (figures on fatalities are not available; the Soviet Union was not keen on admitting to catastrophes at the time.

The aftermath of the 1966 Tashkent Earthquake.

In July 1949 a magnitude 7.4 earthquake in the Gharm Oblast region of Tajikistan (then the Tajik Soviet Socialist Republic), causing a series of landslides and killing over 7000 people (some estimates are as high as 28 000 fatalities).

In 1931 a magnitude in Fuyun County, Xingjiang caused a surface rupture 171 km long, with a maximum horizontal displacement of 14 m. This is now preserved as part of the Koktokay National Geopark. This quake caused about 10 000 fatalities.

In 1907 a 7.4 magnitude earthquake near Qaratog (sometimes Karatog) on the Tajikistan/Uzbekistan border caused between 12 000 and 15 000 fatalities.

See also The End of the Cretaceous and Earthquakes on Sciency Thoughts YouTube.