Life history traits of a temporary water ostracod Heterocypris incongruens (Crustacea, Ostracoda) are affected by power frequency (50 Hz) electromagnetic environmental pollution

摘要

We examined in laboratory settings the effects of power-frequency electric (14 kV/m) and magnetic (150 μT) field exposures, mimicking that of high voltage overhead transmission lines, on the viability of resting eggs of a cosmopolitan freshwater ostracod Heterocypris incongruens . The experiment was carried out in two consecutive phases: (I) an incubation (dry) phase, and (II) a hatching and development (wet) phase. In the first phase, eggs were incubated dry in one of three conditions: electric field, magnetic field and control, and then, in the second phase, the eggs were inundated with water and assigned to one of two hatching conditions: either the same as in incubation or control. Eggs incubated in control conditions were assigned either to the electric field, magnetic field or remained in control conditions. Differences in: hatching success, dynamic of hatchability, and juvenile survival between control eggs/juveniles and those exposed to each of the stress treatment combinations were compared in the balanced design. The magnetic field significantly affected the dynamic of hatchability: 40% of neonates appeared at 4?days in magnetic field treatment vs. 8?days in control; however, final hatching success was equal in all combinations of treatments. Incubation in both magnetic and electric fields significantly affected juvenile survival: only 21.7% (vs. 51.7% in control) and 16.7% (vs. 41.7% in control) of juveniles reached the adult stage in magnetic and electric fields, respectively. We conclude that the power frequency electromagnetic field created by high voltage overhead transmission lines can have important consequences for fitness-related life history traits of aquatic invertebrates.