Earthworm communities (Oligochaeta: Lumbricidae) in old-growth and young forests of protected areas of the Kaluga Oblast (European Russia)

This dataset represents data of earthworms surveys collected in 2 protected areas (Kaluzhskiye Zaseki Nature Reserve and Ugra National Park) in Kaluga Oblast, Russia. Earthworms were sampled by digging-out and hand-sorting (by layers) of the soil samples of 25 * 25 cm and a depth of c. 35 cm in different locations (sampling plots). Some locations were investigated once, some several times within one year or several years. Due to such sampling design the dataset includes 3 types of events: (1) the survey (soil samples collected in the location during one sampling period), (2) soil sample (part of the survey, one sample of 25 * 25 cm and a depth of c. 35 cm collected during the survey), including empty samples, and (3) soil sample layer (part of the soil sample). Occurrence data provide 6673 earthworms occurrences in soil sample layers with life stage (juvenile, adult, or subadult), and biomass for each individual, as well as 271 earthworms occurrences in the survey with density for each survey.