Estimate of the effects of ultraviolet radiation on the mortality of Artemia franciscana in naupliar and adult stages.
The impact of different doses of artificial ultraviolet (UV) radiation on the growth stages of a marine zooplankton was investigated using laboratory microcosms. Mortality percentages of naupliar and adult samples of Artemia franciscana were recorded in relation to different UV doses (single exposure: 75, 150, 300, 600, 1,200, 2,400, 3,900, 7,800 J m(-2)) at specific observation times after exposure (24, 48, 72, 96 and 120 h). The relationship between mortality percentage and UV dose showed significant differences in relation to the zooplankton growth stage. The elevated susceptibility of the naupliar samples to UV radiation is described through a mortality model based on a logistic equation. The data analysis shows that the slope of mortality versus dose remains the same for the two growth stages while the lethal dose in the naupliar stage was 3.3 smaller than that determined for the adult stage. The slope of the UV mortality rate versus post-incubation time was found to be significantly different (P<0.05) at low UV doses for the two life stages examined, i.e. naupliar and adult. The lower value of LD(50) in naupliar stages compared to that for adults confirms that in the early growth stage this marine zooplankton is more susceptible to UV radiation.
Dattilo
Arduino M
AM
Department of Chemical and Biosystem Sciences and Technologies, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy. dattilo@unisi.it
Bracchini
Luca
L
Carlini
Laura
L
Loiselle
Steven
S
Rossi
Claudio
C
D000818:Animals; D001156:Artemia / Q000528:radiation effects*; D007814:Larva / Q000528:radiation effects; D007928:Lethal Dose 50; D016015:Logistic Models; D014466:Ultraviolet Rays / Q000009:adverse effects*