Oligochaeta (Annelidae) in hydrogen sulfide springs in the high North (Usa River catchment, Russia)

Study Extent

The dataset provides information on the number of individuals of aquatic oligochaete in zoobenthos sample.

Sampling

In total, there are five zones of underground sulfide water outlet to the surface (discharge zones). We investigated the zones: Sulfide spring 1, 1.5 km above Iska-Shor Creek mouth (the first and second discharge zones); sulfide spring 2, located behind a rocky ledge on the left bank of the creek at a distance of 2.5 km from the mouth (the third outlet of hydrogen sulfide waters); above sulfide spring 3 and 5. Sulfide spring 1 consists of several small lakes overgrown with sedge and horsetail along the banks. The bottom is rocky, covered with algae, leaf detritus and sand. Sulfide spring 2 forms a shallow streamlet 10 m long and 10 cm deep. The bottom is rocky, covered with sulfide flakes. On the control zone of Iska-Short Creek, located above the springs, aquatic vegetation is well developed, numerous colonies of algae, detritus. The bottom is stone with sand, there is almost no detritus. In the Usa River samples were taken above and below the Iska-Shor Creek mouth

Quality Control

The data were collected and identified by specialists from the Institute of Biology of the Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences. Morphological analysis specimens were performed using compound microscopes BIMAM R13-1, Leica DM 4000B. For identification of species we used both standard keys and data reported in modern studies specifically addressing the taxonomy (Chekanovskaya 1962; Timm 2009; Key to identification of zooplankton and zoobenthos, 2010, Schmelz, Collado, 2010). 1. Key to Identification of Zooplankton and Zoobenthos of Fresh Water of European Russia, KMK Scientific Press, Moscow, 2010, pp. 151–183. [In Russian]. 2. Schmelz R., Collado R. A guide to European terrestrial and freshwater species of Enchytraeidae (Oligochaeta). Soil organisms. Vol. 82. pp. 1-176. 3. Chekanovskaja O.V. Aquatic oligochaetes of the fauna of the USSR. Moscow-Leningrad: Nauka. 1962. 412 pp. [in Russian]. 4. Timm T. A guide to the freshwater Oligochaeta and Polychaeta of northern and central Europe. Lauterbornia, 1999. Issues 66. 235 pp.

Method steps

1. Oligochetae samples were taken with a Petersen grab (sampling area 0.025 m2) on soft bottoms and with a hydrobiological scraper (blade length 20 cm and mesh size of the attached with mesh size ≤158 μm, sampling area 0.04 m2) on gravel bottoms. Samples were preserved in 4% formaldehyde (in the field) and examined under light microscopes in the laboratory. Morphological analysis was performed using a stereomicroscope Leica DM 4000. The worm species affiliation was ascertained under existing taxonomic keys in accordance with the present-day classification of each group. Voucher specimens were deposited at the Institute of Biology, Syktyvkar (Oligochaeta).

1. Annelida
   rank: phylum
2. Oligochaeta
   rank: subclass
3. Naididae
   rank: family
4. Naidinae
   rank: subfamily
5. Tubificinae
   rank: subfamily
6. Enchytraeidae
   rank: family
7. Lumbriculidae
   rank: family
8. Lumbricidae
   rank: family
9. Propappidae
   rank: family

Iska-Shor Creek is a left tributary of the Usa (66 °28ʹ N. 59 °34ʹ E). Five of hydrogen sulfide springs are unloaded into it. The Iska-Shor Stream, about 10 km long, originates from a swamp 6 km above the springs and is formed largely by their waters.