Affiliation:
1. Universidade Federal de Minas Gerais, Brazil
2. Universidade Federal de Ouro Preto, Brazil
Abstract
The fluctuation of the population of Daphnia laevis in Lake Jacaré (Middle River Doce, Minas Gerais) was monitored monthly (at one point in the limnetic region) for six years (2002-2007) as part of the Program of Long-Term Ecological Research (LTER/UFMG). The following parameters were also monitored: water temperature, pH, electrical conductivity, dissolved oxygen, chlorophyll a, total phosphorus, phosphate, total nitrogen, nitrate, nitrite, ammonia, and densities of Chaoborus and ephippia of Daphnia laevis in the sediment. A seasonal pattern was observed in the fluctuation of D. laevis, with higher densities recorded during periods of circulation (May-August). A significant correlation was found between the density of D. laevis and temperature (r = -0.47, p = 0.0001), chlorophyll-a (r = -0.32, p = 0.016) and indicators of the lake's trophic status (total phosphorus, r = 0.32, p = 0.007 and trophic state, r = 0.36, p = 0.003), as well as Chaoborus density (r = 0.43 and p = 0.002). These results indicate that changes in the physical and chemical characteristics of the water related with stratification and circulation of the lake may have a direct (temperature, total phosphorous) or an indirect (food availability, presence of predators, ephippia eclosion) influence on the fluctuation of the D. laevis population.
Subject
General Agricultural and Biological Sciences
Reference42 articles.
1. Uso de Daphnia magna como bioindicador da poluição gerada por efluentes de abatedouros de aves e suínos;BARROS LS;Revista Brasileira de Saúde e Produção Animal,2007
2. Temperature impact on the midsummer decline of Daphnia galeata: An analysis of long-term data from the biomanipulated Bautzen Reservoir (Germany);BENNDORF J;Freshwater Biology,2001
3. The relationship between temperature and duration of egg development in some epiphytic Cladocera and Copepoda from the River Thames, reading, with a discussion of temperature functions;BOTTRELL HH;Oecologia,1975
4. Efípios de Daphnia laevis em lago permanente tropical: mecanismo de resiliência a alterações ambientais?;BRANDÃO LPM,2009
5. Predation, body size, and composition of plankton;BROOKS JL;Science,1965
Cited by
15 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献