Abstract: To investigate the effect of acclimation temperature on thermal and hypoxia tolerances, the relevant indicators were measured in juvenile rose bitterling (Rhodeus ocellatus) after 14 days of acclimation at 15, 20 or 25 ℃. The critical thermal maximum (CT_max) and lethal thermal maximum (LT_max) increased with the increase of acclimation temperature, while the critical thermal minimum (CT_min) and lethal thermal minimum (LT_min) decreased with the decrease of acclimation temperature, suggesting that the thermal tolerance of rose bitterling is highly temperature sensitive. The thermal tolerance amplitudes at 15, 20 and 25 ℃ were 29.34, 30.18 and 28.01 ℃, respectively. The acclimation response ratio (ARR) of CT_max was similar between different temperature ranges (0.40 for 15-20 ℃, and 0.44 for 20-25 ℃), whereas the ARR of CT_min was relatively high in high temperature range (0.87) when compared to that of low temperature range (0.23). This suggests that the cold tolerance of rose bitterling is more sensitive to the change of temperature at high temperature range. Furthermore, the increasing loss of equilibrium at high temperature suggested that the hypoxia tolerance decreased with the increase of acclimation temperature.

Key words: interspecific relationship, ecological species group., oderately degraded tiankeng, plant community