The Site is composed primarily of fen mires with numerous scattered forested islands. It is one of the largest mesotrophic fen mires in Europe preserved in its natural state. The wetland supports populations of plant and animal species important for maintaining the biological diversity of mire ecosystems of the Continental biogeographic region. The highest diversity of plants is found in the mineral islands, which are microrefugia for several threatened species. The Site also supports open sedge communities of Caricetum chordorrhizae, Caricetum juncellae and Caricetum limosae, providing an important habitat for the globally endangered aquatic warbler Acrocephalus paludicola. The globally endangered European bison Bison bonasus use the area as a foraging and resting place. The wetland provides important hydrological services, and feeds the Rivers Narev and Yaeslda, which originate in the central part of the mire. Local communities use the Site to collect berries and mushrooms. An information centre is located within the "Belovezhskaya Pushcha" National Park. Due to adjacent melioration systems, the water level in a marginal area of the eastern part of the mire has decreased leading to the development of shrubs and trees. In addition, the area of open sedge mires is shrinking due to the cessation of traditional mire use. This has led to the rapid overgrowth of the open mires with shrubs and reeds, and a decrease in the numbers of the aquatic warbler.