Response of Bosmina to climate variability and reduced nutrient loading in a large lake

• Published in: Limnologica Vol. 40; no. 2; pp. 92 - 96
• Main Authors: Straile, Dietmar, Müller, Helga
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 01-05-2010
• Subjects: Bosmina; Bosmina coregoni; Bosminalongirostris; Cladocera; Daphnia; Freshwater; Lake Constance; Long-term time series; Marine; North Atlantic Oscillation; Oligotrophication; Seasonal dynamics; Spring bloom; Europe, Constance L; AN, North Atlantic, North Atlantic Oscillation; Germany, Baden-Wuerttemberg, Bodensee L; Oligotrophication; Spring bloom; North Atlantic Oscillation; Seasonal dynamics; Daphnia; Lake Constance; Long-term time series
• ISSN: 0075-9511; 1873-5851
• DOI: 10.1016/j.limno.2009.11.004

The long-term dynamics of the cladoceran
Bosmina spp. were analysed in Lake Constance during the study period 1979–1998. During this period the lake ecosystem has been influenced strongly by changes in nutrient inflow (oligotrophication) and by climate variability associated with the North Atlantic Oscillation.
Bosmina abundances declined strongly during the study period presumably as an indirect consequence of the reduced P loading of the lake. A detailed seasonally resolved analysis of
Bosmina dynamics revealed that its abundance decline occurred throughout the year with the exception of the spring period. The lack of a population decline during spring may be attributed to the seasonal absence of the factor, e.g., food limitation and/or predation control by invertebrates causing the population decline. Additionally, climate variability had its strongest influence on
Bosmina dynamics during spring and large climate-associated variability of
Bosmina may have decreased the power to detect a significant reduction in spring
Bosmina abundances with oligotrophication. However, when we account for the confounding influence of climate variability, the effects of oligotrophication are revealed more clearly also during the spring period. Likewise, the detectability of the influence of climate variability on spring
Bosmina dynamics increases when accounting for the reduction of abundances in the course of oligotrophication.