An Unseen Airborne Contaminant
The Chatkal Mountain Forest State Biosphere Reserve, established in 1947, is a protected area in the Western Tien Shan mountains. Spanning vast tracts of juniper forests and alpine meadows, its rugged terrain was thought to be a sanctuary from many forms of human impact. However, recent studies on atmospheric pollution show that this is not true. Microscopic plastic particles, smaller than 5 millimeters, are carried by atmospheric currents and deposited in remote locations, including the high-altitude snowpack of the Chatkal range.
This phenomenon, known as atmospheric deposition, means that plastic waste from urban and industrial areas can travel thousands of kilometers. Scientists studying snow samples in other remote mountain and arctic regions have confirmed the presence of a variety of microplastics. Research in nearby Central Asian regions found that 92.6% of snow samples contained microplastics, with concentrations recorded up to 12 particles per square meter. The most common forms are fibers, fragments, and films. These particles originate from the breakdown of larger plastic items, textiles, and industrial processes.
A Fingerprint of Pollution
Analysis of microplastics from remote snowpack often reveals the types of polymers being transported through the air. Common culprits identified in various studies include polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET)—polymers used in everyday items like bags, bottles, and clothing. The presence of these materials in a protected biosphere reserve demonstrates a global pollution challenge that transcends borders.
The Chatkal Biosphere Reserve itself has significant natural value. It is divided into two main sections, Boshkizilsoy and Maidontol, with peaks reaching over 3,800 meters. This high-altitude environment hosts rare species like the snow leopard. The accumulation of microplastics in the snow has potential consequences for the local ecosystem. As the snow melts, these particles enter the soil and waterways, including the Bashkyzylsai and Serkelisai rivers, becoming available to plants and wildlife. This introduces synthetic, persistent materials into the foundation of a protected food web.