Impact of climate change on water resources of the Pyanj River basin of the Republic of Tajikistan

“A radical solution to the problem of water scarcity and overcoming the risks associated with climate change and natural disasters are seen in the development of hydropower with integrated reservoirs, with the cooperation of stakeholders.” Emomali Rahmon, President of the Republic of Tajikistan.

Annotation

Tajikistan is considered the most vulnerable Central Asian country to the adverse effects of climate change. Key areas such as the Pyanj River Basin are already experiencing recurring losses from natural disasters, including flooding, landslides and droughts. Recent droughts and extreme weather have clarified existing inadequacies in most sectors: for example, the inability of irrigation infrastructure to support agricultural production due to water loss, low levels of irrigation efficiency, flooding, soil salinization, and declining yields. Climate events indicate that Tajikistan will see temperatures rise to 2 degrees Celsius by 2050 and average precipitation will decrease. The increase in temperature will lead to accelerated melting of glaciers, with the likely disappearance of 30% of the mass of glacial systems by 2050

Key words: impacts of climate change, the Pyanj river basin, natural disasters, flooding, landslides, drought, glaciers, glacial lakes, irrigation infrastructure, precipitation, climatic cataclysms, water shortages.

There are more than 10 thousand large and small glaciers on the territory of Tajikistan, the volume of which is more than 850 cubic kilometers. The largest and on land is the Fedchenko Glacier, which is 76 kilometers long and has a total volume of 144 cubic kilometers. The Fedchenko Glacier is a regulator of the Vakhsh River and an indicator of the climatic state of Central Asia. The total area of ​​all glaciers in the country is 6% of the total area of ​​the republic. Over the past 40-50 years, more than a thousand glaciers of the republic have melted under the influence of climate warming some small glaciers have completely disappeared. With an increase in average air temperature from 1.8 to 2.5 degrees by 2050, the trend of melting glaciers will continue and the number of glaciers will be reduced by half.

It should be noted that a significant part of the water resources of Central Asia is concentrated precisely on the glaciers of Tajikistan. Thus, the melting and disappearance of glaciers in the country poses a huge threat to the entire region as a whole.

Maximum seasonal runoff is likely to be carried over from early spring to late winter. As a result of these changes, significant consequences of the availability of water for human consumption, irrigation, and hydropower production are expected. In particular, higher temperatures will lead to increased evaporation and increased water scarcity in summer. The adverse impacts of climate change will be acutely felt by the part of the population that is already vulnerable by gender, age, (or disability), 75% of the poor live in rural areas. It is assumed that climatic disasters can drive a large percentage of the population into extreme poverty. Climate change is likely to bridge existing food security concerns and greatly affect those dependent on agriculture. Women and children, who make up the larger population of the country, are vulnerable to the impacts of climate change in Tajikistan. They are often charged with the responsibility of securing water, food, cooking fuel, and space heating in rural Tajikistan. Thus, for their existence they are dependent on natural resources that are threatened by climate change.

The Pyanj River has an international border between Afghanistan and Tajikistan. The basin area of ​​the river is about 107,000 square kilometers (of which 40% is in Afghanistan and 60% in Tajikistan) in mountainous terrain, stretching along the lower floodplain with an area of ​​about 6,500 square kilometers. The length of the Pyanj River is about 1000 km before its transformation into the Amu Darya River after its confluence with the Vakhsh River. The Bartang, Gunt and Vanj rivers (basin 2070 km² and 92 km long), Yazgulom and Kyzylsu are one of the largest right tributaries of the Pyanj River, as well as the Chordara, Khumbob and Yakhsu, rivers join to form the Pyanj River.

The basin area of ​​the Yazgulom River is 1970 km², and its length is 80 km. The length of the Bartang River is 558 km, the basin area is 24,700 km², the length of the Gunt River is 296 km, and the basin area is 13,700 km². It is the largest tributary of the Pyanj River in terms of both basin area and length. According to the current flow, the largest right tributary of the Pyanj River is the Kyzylsu River, which is 230 km long and has an area of ​​8630 km². From this basin, the zone of the Kulyab region and the Pyanj region will be provided with irrigation water.

The drainage network of the Kyzylsu River Basin (Mir Said Ali Hamadoni, Farkhor and Kulyab districts) is mainly located at the level of the river and consists of the volume of fresh water discharged from the Pyanj, Kyzylsu, Yakhsu river which are almost equal to the source of the taken water. The Kafirnigan River also divides the Kabadiyan Valley from north to south and flows into the Pyanj River

The Pyanj River has a large amount of sediment, and it is estimated that about 750,000 m³ of sediment flows into the Chubek irrigation system each year, which is a huge burden on the budget for the operation and maintenance of the cleaning of the irrigation network. The bottom sediment is discharged back to the Pyanj River at the Gateway-Regulator of the Main Channel Chubek through a drain channel with a threshold level of 60 cm. So the concentration of sediment is associated with a spillway, about 84% of the sediment enter the Chubek irrigation system during the three months of summer June, July, August. Fortunately, hydrology and existing infrastructural facilities contribute to the construction of an efficient and reliable sediment-diverting basin, which could be located at the beginning of the Chubek Main Canal section.

Poor flow and sediment registration status seriously affects factors such as:

• First, inadequate irrigation systems are evident from the general agricultural production situation, indicating low acreage, low yields and lower than total agricultural production. Water demand for yields for future cropping systems and intensities should be based on agro-climatic factors rather than historical records.
• Second, irrigation efficiency is an important parameter for calculating future irrigation needs. In the course of the research, attempts were made to assess the efficiency of irrigation using remote sensing data. Although this method provides reasonably reliable estimates of total water consumption, actual flow data is required to measure the level of efficiency, and the reliability of the measured level of feasibility of irrigation will not be better than hydrological observations.
• Third, the current state of these flows and sediments underscores the need for a strong and well-equipped institutional mechanism with trained staff to regularly observe, analyze and record observational data. Adequate resources should be allocated to purchase appropriate field equipment to monitor water discharge and sediment sampling in the basin, establish laboratories for analyzing sediment samples, and train appropriate personnel.

Agricultural resources

During the Soviet Union there was no shortage of quality seeds, pesticide fertilizers. There is currently an acute shortage for all three, prices are high and quality is low. Wheat seeds can contain up to 20-30% of impurities therefore the quality of the seeds must be very high. The varieties available vary from year to year and may not be suitable for the region. The seeds do not come with an official certificate and etiquette. While there are several control systems and seed supply units in the Ministry of Agriculture, the system clearly fails to supply the appropriate seed to farmers. Two fertilizer plants were closed during the Soviet Union and all fertilizers are imported, there are many complaints about the cost and quality of the imported fertilizers. Few farmers have the availability to pay for fertilizers or equipment.

The staff of each jamoat has an agronomist. While this is good, agronomists need training and support along with resources to provide advice / services to farmers.

Water demand

Different crops require different amounts of water depending on the time of planting and harvesting, and the water requirement for winter vegetables is much lower, about 1/3 of summer vegetables. The following are actions to improve farm management and water efficiency in the Pyanj River Basin areas in order to increase agricultural productivity and farm incomes, thereby reducing poverty, which is:

• Through demonstration sites, disseminate a wide range of agronomic practices, agricultural technologies and farm water management techniques to promote efficient water use and higher water productivity;
• Introduction and multiplication on local farms of high quality seeds of improved varieties of wheat, cotton, vegetables and other important crops;
• Development of the institutional capacity to expand the district agriculture staff, so that they can transfer and continue to advise farmers on agricultural technologies and fulfill irrigation supply and responsibilities in an efficient way.
• Facilitate the reorganization / creation of water user associations (WUAs) at hydrological boundaries and develop the capacity of WUAs as well as beneficiaries in water use management and their official business. Improving the skills of beneficiaries and encouraging value chain creation and added value

In Tajikistan, an effective system of management of activities for the prevention, elimination earlier increase, assessment of the hazard and risk of natural disasters has been established. The most vulnerable zones of the territory have been identified, where educational and methodological gatherings, trainings, trainings and exercises are held to raise awareness of the population about possible emergencies or natural disasters. Special programs have been developed for the preparation and training of secondary school students, students of higher educational institutions, commanding staff, as well as workers, employees and the population of the republic on the basics of natural disasters and emergency situations.

There is a multilateral and bilateral international agreement on cooperation with regional, world and international organizations in the field of disaster risk reduction.

Considering that 40% of the Pyanj River Basin covers Afghanistan, and in this regard, serious flooding has often occurred, in 2010 the two states signed a bilateral agreement for joint hydrological monitoring of the Pyanj River with the support of development partners including ADB. Subjects of cooperation include coordination and assistance in the installation and modernization of meteorological stations on the Pyanj River, conducting mutual expeditions, training, exchange of experience, as well as organizing meetings, scientific seminars, round tables. The parties also developed an action plan to create a joint commission for the Pyanj River Basin. Today, both states are trying to find technical and financial support to implement the action plan.

It should be noted that over the past 15 years in neighboring Afghanistan in 23 districts, 4 northern regions of Balkh, Chavzon, Tahor and Kunduz, more than 14,685 hectares of arable land have been washed away by the river movement of the Pyanj River.

In recent years, the number of natural disasters in the Republic of Tajikistan has increased significantly, which affected the nature, socio-economic situation of the republic and the well-being of the country’s inhabitants. Long-term observations of temperature indicate that in recent years the average annual air temperature in the Republic of Tajikistan has increased by one degree Celsius, and the frequency and intensity of natural hydro meteorological events has also increased.

For the country’s agricultural sector, which employs more than 60% of the population, such disasters are particularly devastating. About 75% of women and 42% of men in the country are employed in the agricultural sector, and more than 1 million people are constantly food insecure and subject to recurring climate shocks.

High temperatures in recent years have caused massive glacial floods and mudflows, which have eroded vital infrastructures, crops, transport networks, power grids, embankments and waterworks, which require months or years to rebuild and require large financial costs. The emergence of natural disasters due to climate change, in addition to high seismic activity, threatens to undo much of Tajikistan’s progress over the past few decades. Over the past 25 years, a series of major natural disasters has been observed across the country, as a result of which they have resulted in economic losses of more than 2.1 billion US dollars, and have affected more than 80% of the country’s inhabitants and mainly affected the most vulnerable segments of the population.

Every year, the Government of the Republic of Tajikistan directs multimillion budgetary and extra-budgetary funds to prevent and eliminate natural disasters. Part of these funds are directed to resettlement of the affected population, to provide them with material assistance. Another part is used for the restoration of damaged infrastructure, construction and restoration of bank protection dams. In addition, a program on adaptation to climate change has been developed, the purpose of which is to improve the adaptation monitoring system and the early warning system, as well as research work has been carried out.

Global climate changes have a direct impact on the activation of natural processes in our country. The rise in temperature has led to droughts partly natural disasters have manifested themselves the area of ​​glaciers has decreased from which the main rivers supplying our country and the Central Asian region feed. Further warming could threaten the entire energy industry and agriculture of this Republic of Tajikistan. In this regard, the Government is developing urgent measures to adapt to climate change. Solving these problems requires joint efforts of the Central Asian states, authorities, NGOs and citizens of the region.

Water and agriculture of the republic can be significantly affected by climate change. It is known that crops require more water, especially for irrigation, taking into account plant evapotranspiration. The irrigation norms of the main agricultural crops will also increase, land degradation will occur, and there will be risks of developing desertification processes in the southern and central regions of the republic.

Overall forecast:

Several thousand small glaciers will completely disappear in Tajikistan by 2050. The degradation of glaciers will most strongly affect the runoff of the Zeravshan, Kafirnigan with tributaries, Obikhingou. The glacier area of ​​the country will decrease by 20%, the volume of ice will decrease by 25%, but the largest, most important glaciers will remain, although they will become somewhat shorter, and their tongues will be located higher. The glacial runoff of the Pyanj will hardly change the runoff of the Vakhsh River will decrease somewhat due to a decrease in the runoff of the Obikhingou River.

The glaciated area of ​​the country may decrease in comparison with the present time by 15-20% and the water reserves in glaciers by 80-100 cubic km. But large glaciers and glacial nodes will remain. Glacial runoff Pyanj, Vakhsh and the Amu Darya as a whole, due to the active melting of glacial reserves may initially increase, but in the long term, on the contrary, decrease due to the depletion of ice reserves. An unfavorable change in the hydrological regime of rivers can have serious consequences for both individual vulnerable communities and the entire region.

It is gratifying that fundamental research has begun in Tajikistan in the field of studying the state of glaciers, in glaciology and the cryosphere. On behalf of the President of the Republic of Tajikistan, the State Scientific Institution “Center for the Study of Glaciers of the National Academy of Sciences of the Republic of Tajikistan” was established in 2018. Currently, the Center conducts expeditions, improves scientific discoveries in the field of cryosphere and glaciology, and also fixes the state of glaciers, which will allow in the near future find out the exact number and state of existing glaciers in the Republic of Tajikistan. Also, new scientific and fundamental research in the field of cryosphere and glaciology has been revived in the republic, which will allow the Center’s employees to start preparing the “Atlas of Tajikistan’s Glaciers”. Based on the above-mentioned achievements, Tajikistan is included in the Unified Global Glacier Monitoring System, and the Center is a member of the World Meteorological Organization for Cryosphere and Hydrology.

The Center, together with Swiss colleagues, organized a joint expedition to the Zulmart and Yakarcha glaciers, whose tributary forms the Pyanj River, where an automatic meteorological station was installed. The weather station is connected to sensors and can record and store glacier data throughout the year. One of the significant results of the Center is the use of unmanned aerial vehicles to study glaciers with a resolution of 5 to 7 centimeters. Comparison of satellite data and the received information of drones will allow us to pinpoint the location of the glacier on the map. In addition, research on glaciers is carried out using GPS, GIS, Arc GIS, Qu GIS, Sanitel LandSAT.

Tajikistan is one of the most vulnerable countries in Central Asia, and climate change poses a serious threat to the entire region. Therefore, it is necessary to actively consolidate collective efforts in the field of adaptation to climate change and emergency situations at the regional level.

Conclusion

Comparison of the retrospective average annual flow rates of the main rivers in the Pyanj Basin with future indicators according to the forecasts of hydro climatic models suggests that by 2100 a gradual increase in the annual flow of the Pyanj River is expected. In particular, these risks will manifest themselves in the form of: increased water demand, especially for irrigation, due to higher air temperatures and evapotranspiration, which will lead to water shortages. This could happen by the end of this century and will have an impact on agriculture, livelihoods and ecosystems. Periods of extreme heat or cold may occur, affecting human and livestock health and agricultural production. Damage to life and property, agriculture, livelihoods and ecosystems will increase due to more frequent mudflows (sudden avalanches, flows carrying sedimentary material caused by heavy rainfall and snowmelt, especially during the spring season), as well as due to annual flooding of glacier-fed rivers with melt water. According to researchers’ forecasts, the main climate changes will be as follows:

• The air temperature in the Pyanj River Basin will increase by about 1.7 ° C from 2010 to 2050, and by 3.5 ° C from 2050 to 2100;
• Average annual total evaporation will increase as air temperature rises;
• Significant changes in the chronological profile of mean monthly rainfall and snowfall can also be expected;
• There may be gradual changes in the seasonal distribution of river flow, with higher flows closer to the beginning of the year as a result of earlier melting of snow and ice caused by rising air temperatures;
• The magnitude and frequency of mudflows and floods are likely to increase.

Glacier regulation perspectives

Continental prospects, climate warming and the resulting degradation of glaciation are global processes, covering the entire planet, all continents of the Earth. In half a century, the glaciation of Uzbekistan will disappear, in a century and a half, according to the estimates of glaciologists of Kyrgyzstan all small and medium glaciers of the Tien Shan will melt. And humanity is not yet able to combat this phenomenon. Instead of fighting, it is necessary to adapt to the changing environment, when the average air temperature rises and glaciation decreases. Glaciers experts propose measures to manage the regime of mountain glaciers. However, upon closer examination, it turns out that almost all of them are unsuitable for the conditions of Tajikistan:

• An artificial increase in precipitation is still under development. At the height of summer, with high temperatures and low air humidity, it is almost impossible to artificially cause precipitation in Central Asia.
• Artificial discharge of avalanches is used nowadays only on some roads and mines, but it is impossible to apply it in all mountainous regions of Tajikistan. With a decrease in the amount of precipitation in the form, the number of avalanches will also decrease.

Thus, almost all of the listed measures to regulate ice melting are not suitable for the conditions of Tajikistan. The only exception is the “accumulation of autumn runoff in a buffer tank”, that is, the creation of reservoirs in the mountains. They must store melt water in the off-season when the fields do not need it. It is desirable that the surface of the reservoir is as small as possible and the depth as large as possible: this reduces evaporation losses. At the same time, reservoirs should be safe, in the event of a breakthrough (landslides, landslides, mudflows, destruction of dams by an earthquake), the damage should be minimal. Such dams can be created by the explosion method or built capital ones, made of reinforced concrete, with emergency discharge, in case of overflow. Reservoirs without hydroelectric power plants, intended only for irrigation, already exist in our republic: Selbur, Muminabad, but they are located in the valleys.

The second way to combat low water levels caused by degradation of glaciers is to build pumping stations that supply water from large rivers to terraces and slopes.

And, of course, one of the main ones is water-saving, economical irrigation: closed aqueducts, siphons, irrigation ditches, replacement of the entire technology of our agriculture with a more modern one, used in the countries of the Near and Middle East with a hot arid climate and little rainfall.

Literature:

1. “Water cadastre of the Republic of Tajikistan”, published by the State Enterprise “TajikNIIGiM”, Dushanbe, page 8. 2020.
2. Main Report TA 8647-TAJ: “Water Resources Management in the Pyanj River Basin” source Ministry of Energy and Water Resources of the Republic of Tajikistan Dushanbe, November 2015.
3. Report on “Migration of the Pyanj River – Amu River from 2000 to 2019” National Statistical and Information Center of the Islamic Republic of Afghanistan NSIA, Shuob Saburi 2019, Afghanistan.
4. “Fundamental research has begun in Tajikistan to study the state of glaciers” Materials of the State Scientific Institution “Center for the Study of Glaciers of the National Academy of Sciences of the Republic of Tajikistan” 2019, Dushanbe.