We cannot prevent dust storms; therefore, it is necessary to find and implement adaptation methods to reduce the impact of dust storms, says CABAR.asia expert Muazama Burkhanova.
In recent years, environmental scientists have become increasingly interested in studying the impact of dust aerosol on the surface layer of the atmosphere, the environment, economic development, public health, and the possibilities of adaptation to changed conditions. On June 8, 2023, the UN General Assembly proclaimed July 12 the International Day of Combating Sand and Dust Storms. The aim of this is to raise awareness of the effects of dust storms on the health and sustainable development of countries.
The draft resolution on combating sand and dust storms adopted by the United Nations Environment Assembly (Sixth Session, Nairobi, February 26 – March 1, 2024) invites UN Member States to enhance the sharing of best practices and knowledge on all relevant aspects of combating sand and dust storms, to mitigate their negative impacts as appropriate, including the socio-economic impacts of sand and dust storms, impacts on ecosystems, and public health and well-being, with particular attention to people in vulnerable situations.
Climate change has a great impact on the frequency and intensity of sand and dust storms (SDS), which are interrelated in many aspects: droughts, extreme temperatures, changes in precipitation patterns, land degradation, changes in wind patterns (wind rose), etc.
The first publications on the SDS in Tajikistan were reports from scientists at the S.U.Umarov Physical-Technical Institute of the National Academy of Sciences of Tajikistan in 2007 (https://phti.tj). According to the Laboratory of Atmospheric Physics of this Institute, the southern and central parts of Tajikistan are located in the global dust belt; dust from the deserts of Aralkum, Kyzylkum, Karakum, Gobi, Takla-Makan, Iranian deserts Dasht-e Lut and Dasht-e Kavir, as well as from the drying Aral Sea is transported to this territory across the southern border of the country. Mountain valleys and cities are often wrapped in dust clouds and suffer from its impact.
Over the last 30 years, the number of dust storm episodes in Tajikistan has increased at least 10 times. In the early 1990s, they occurred two or three times a year; in recent years, up to 35-45 dust storm episodes are registered annually.
The long duration intensifies the negative impact of SDS; dust can stay in the air and cause problems for days or even months, while dust storms themselves can be over in a matter of minutes.
Dust Storms’ Impact on Public Health
Air pollution causes significant public health damage and economic losses in Tajikistan. According to a World Bank study (“The World Bank. 2023. Air Quality Management in Tajikistan. ©World Bank”), the attributed mortality rate due to PM2.5 pollution is estimated at 78 deaths per 100,000 inhabitants. This is the second highest rate in Central Asia.
Overall, 4,800 deaths are attributable to ambient air pollution in Tajikistan, mostly due to ischemic heart disease (51%) and stroke (27%). Another air pollutant with considerable health impacts is ozone, to which 60 to 230 deaths can be attributed. According to the World Bank, the corresponding health costs are estimated to be 4% of the GDP of Tajikistan. Other impacts of air pollution are loss of crop yields (due to ozone) and accelerated melting of glaciers (due to black carbon).
1 in 5 infant deaths in Europe and Central Asia is linked to air pollution. The health effects of dust storms are characterised by the following: eye, nose, and throat irritation; coughing and wheezing; respiratory diseases; asthma; bronchitis; chronic obstructive pulmonary disease; allergies; brain inflammation; etc.
Public health is receiving increasing attention at the international level.
- At COP28 in Dubai in 2023, the first ever Declaration on Climate and Health was adopted, endorsed by 151 heads of state and government, reaffirming the focus on health at the discussions during UNFCCC meetings.
- Parties to the UNFCCC have recognised the fundamental human right to a clean, healthy environment. Governments have endorsed the inclusion of public health actions in the Nationally Determined Contributions (NDC) and other national climate policies.
- Resolution 58.22 (WHA) urged Member States to pay special attention to diseases caused by exposure to chemicals at the workplace.
Dust Storms’ Impact on Air Quality
- According to the Physical-Technical Institute of the National Academy of Sciences of Tajikistan, aerosol in air during strong dust storms coming from the south and west contains several heavy metals such as hexavalent chromium (Cr(VI), arsenic (As), cadmium (Cd), nickel (Ni), which are included in the group 1 and 2 of the dangerous carcinogens. Heavy metals from the atmosphere accumulate in plants, animals, and enter the human body via the food chain.
- It is important that, unlike organic pollutants, heavy metals are not destroyed over time, but transform from one form to another, mixing in the composition of salts, oxides, organometallic compounds. Dushanbe city’s air quality is significantly affected by toxic emissions from transport, 2 thermal power plants, a cement plant, industrial enterprises of the city (using coal as fuel), waste from the housing and utilities sector of the city, private sector activities, etc.
- Even in clear weather and visibly clear skies, Dushanbe’s air quality indicators show harmful levels (232 AQI, 14.09.2024). The causes of air pollution are transport exhaust (nitrogen dioxide, lead, particulate matter), industrial and private emissions from coal combustion (arsenic, sulphur dioxide, carbon monoxide), lack of wind, which prevents the dispersion of harmful emissions, as well as a small proportion of broadleaf tree plantations that trap the city’s harmful emissions.
- Ground-level ozone emissions are represented by the concentration of dangerous pollutants under intense solar radiation and greatly affect the city’s ecology. Ground-level ozone seriously affects health: it causes asthma, chronic obstructive pulmonary disease, pollen allergies. Infants and children are particularly at risk from dust storms.
Dust Storms’ Impact on Agriculture
- SDS damage crops and the fertile soil layer: they remove the top layer of soil, which is the most fertile and contains the nutrients necessary for plants. This reduces the fertility of the land and can lead to lower yields.
- Crop damage: strong winds and the sand and dust they carry can physically damage plants, reducing the plant’s ability to absorb light.
- Water bodies pollution: sand and dust carried by storms can accumulate in water bodies, causing silting and reducing the quality of water used for irrigation and drinking.
- Microclimate change: dust storms can change the microclimate by reducing sunlight and photosynthesis in plants, as well as changing temperature and humidity levels.
- Diseases and pest insects: damaged and weakened plants become more susceptible to disease and pest attacks, which can further aggravate yield losses.
How Can the Dust Storms’ Impact Be Minimised?
We cannot prevent dust storms; therefore, it is necessary to find and implement adaptation methods to reduce the impact of dust storms.
The negative impact of SDS on crop yields could be reduced by:
- Creation of the protective forest belts around the fields can significantly reduce wind speeds and reduce the amount of dust reaching the crops.
- Cover crops: planting cover crops between main crops reduces soil erosion and holds the top layer of soil in place.
- Soil tillage practices, which could include minimum or zero tillage practices, help to maintain soil structure and keep crop residues on the surface, which will reduce soil erosion and protect soils from wind damage.
- Crop rotation: diversity in planting crops improves soil structure and soil resistance to erosion.
- Irrigation and soil moistening: moisturised soil is less likely to be swept away, so irrigation during dry periods can help keep soil in place.
- Strengthening the top layer of soil with organic and mineral additives makes it less susceptible to erosion.
- Installing temporary or permanent barriers made of different materials reduces wind speed and dust.
- Crop covering: it can be effective in some cases to place special filters or nets over fields to protect plants directly during storm periods.
It is also important to monitor weather conditions. Modern forecasting systems can warn farmers of approaching storms, allowing them to take preparatory measures to protect their crops.
It is time to return to the use of traditional knowledge in land and water use: biological drainage, takyr, chirle, sardobes, etc. (Information handbook “Traditional Knowledge in the Field of Land and Water Use”, FSCI, Dushanbe, 2006).
In the Karakum Desert territory in Turkmenistan, the ancient method of creating takyrs [a land formed by the drying out of saline soil – Tr.] to collect rainwater for growing pistachio orchards is now successfully applied.
Public awareness and access to healthcare to treat and prevent diseases caused by dust storms need to be strengthened. Health deterioration from polluted air leads to long-term damage to generations, increased poverty, the appearance of climate refugees, and deterioration of the nation’s gene pool.
One of the adaptation measures to reduce the impact of dust storms in Tajikistan is reforestation. Forestry is an important sector of the country’s economy. Environmental benefits of forests include increased biodiversity, improved air and water quality, and reduced soil erosion. Economic benefits are the improvement of public health, development of ecotourism, and creation of new jobs.
Tajikistan pays great attention to the revitalisation of green areas; many government documents have been developed in this direction. One of them is the Forest Sector Development Strategy for the period of 2016-2030 developed by the Committee on Environmental Protection under the Government of the Republic of Tajikistan.
An action plan for the third phase of the Strategy is currently being developed to address the new major factor – sand and dust storms.
Reforestation takes time and effort, with results only visible after decades, so sustainable plans and long-term commitments are required.
To prevent dust storms in southern Tajikistan, the largest saxaul plantation on more than 300 ha is being planted (with the support of the Government of Tajikistan and the Government of South Korea, 2020-2023). For this, more than 250,000 saxaul seedlings are being grown in the natural area of Ayvaj in Shahritus district for further planting in the desert area of the district. Saxaul protects the sandy soil from wind and retains sand, preventing wind erosion to some extent. To trap dust and salt, moisten the air, forest belts with broadleaf trees should be planted that hold dust, salt, and strengthen the soil (tamarix, sand acacia, oleaster, turanga, maple, elm, ash, calligonum, etc.).