70375 Реферат:
The spatial distribution of healthy and diseased sponges in Lake Baikal was investigated. The endemic sponges
were studied in May−June 2015 at 11 transects within the depth range of 0 to 40 m. More than 500 sponge specimens were collected, and 29 taxa including 12 species and 17 morphospecies (sp. taxa) were identified. Among
the 29 taxa, only B. martinsoni specimens and 14 morphospecies were healthy, whereas specimens of the other
11 species and 3 morphospecies were diseased, making up 35% of the total number of specimens (512). The different body forms of sponge found among the specimens were encrusting (66%), globulous (21%), and branched
(13%). Sponges with necrosis signs, discolored specimens or covered with violet film or brown spots, were found
in all transects under study (37 stations of 68). The percent cover of the bottom (per m2) by various body forms of
sponges was evaluated with a sponge faunal state assessment test. Changes in the diversity and abundance of
sponges due to their disease may jeopardize the functioning of the entire ecosystem of Lake Baikal which is a
World Heritage Site. This baseline data on patterns of sponges, including their spatial distribution and percent
cover, will be utilized to support future management and monitoring of Lake Baikal. Data on the current state
of Baikal endemic sponge fauna are essential for understanding the causes and prognosis of disease processes
of freshwater sponges.