Dave G
Comp Biochem Physiol C Comp Pharmacol Toxicol. 1984;78(2):433-8. doi: 10.1016/0742-8413(84)90111-7.
The effects of waterborne iron (FeCl3 X 6H2O) on growth, reproduction, survival and haemoglobin content in Daphnia magna were studied from subnormal to toxic concentrations in hard reconstituted water. Low concentrations of iron stimulated reproduction and haemoglobin synthesis after chronic exposure for 21 days. Maximum reproduction occurred between 0.1 and 1 microgram Fe 1(-1). Juvenile growth was not stimulated by iron but was slightly inhibited between 1 and 8 micrograms Fe 1(-1) and above 128 micrograms Fe 1(-1). A slight inhibition of growth persisted for 21 days. Total haemoglobin content was above the control with no waterborne iron at all but one concentration (512 micrograms Fe 1(-1]. The highest value (3.8 X control value) was found at 2 micrograms Fe 1(-1). The haemoglobin content decreased between 64 and 512 micrograms Fe 1(-1) and increased at higher concentrations. The decrease coincided with an inhibited reproduction. The increase was found in non reproductive survivors. A comparison with a previous study in D. magna suggests that ambient conditions (hardness and pH) and ageing of the water are important for the effects of waterborne iron. At a hardness of 250 mg 1(-1) as CaCO3 and a pH range of 7.0-8.0 the ZEP (Zero Equivalent Point) for reproduction was 158 micrograms Fe 1(-1). Continuous exposure to higher concentrations is expected to lead to extinction of a D. magna population.
在人工配制的硬水中，研究了从低于正常浓度到有毒浓度的水载铁（FeCl₃·6H₂O）对大型溞生长、繁殖、存活及血红蛋白含量的影响。在经过21天的慢性暴露后，低浓度的铁刺激了繁殖和血红蛋白合成。最大繁殖率出现在0.1至1微克铁/升之间。铁未刺激幼体生长，但在1至8微克铁/升以及高于128微克铁/升时，幼体生长略有抑制。这种轻微的生长抑制持续了21天。除了一个浓度（512微克铁/升）外，总血红蛋白含量在完全没有水载铁时高于对照组。在2微克铁/升时发现最高值（为对照组值的3.8倍）。血红蛋白含量在64至512微克铁/升之间下降，在更高浓度时上升。这种下降与繁殖受抑制同时出现。在非繁殖存活个体中发现了上升情况。与之前对大型溞的一项研究比较表明，环境条件（硬度和pH值）以及水的老化对水载铁的影响很重要。在硬度为250毫克/升（以碳酸钙计）且pH值范围为7.0 - 8.0时，繁殖的零当量点为158微克铁/升。预计持续暴露于更高浓度会导致大型溞种群灭绝。
