Effects of low pH and humus on the survivorship, growth and feeding of Gammarus pulex (L.) (Amphipoda)

摘要: SUMMARY. 1. The toxicity to the freshwater amphipod Gammarus pulex (L.) of soft water (pH6.0) with three concentrations XAD-extracted aquatic humus was treated in laboratory. 2. Exposure pH6.0 without added resulted 92% mortality after 3 weeks. Humus, at 7 and 20 g Cm 3, decreased 80% 64% same period. 3. Surviving animals kept had a lower growth rate, food conversion efficiency higher body content than pH 7.3. 4. Humus no significant effects on growth, or composition G. 6.0. However, there tendency for increase, decrease increased concentration. observed this study do not support contention that acts as free coupler metabolic efficiency. On contrary, tended benefit conversion. 5. It is suggested low can be directly beneficial organisms acidified ways other by complexing toxic metals.