体重与氨氮浓度对河蚌氨氮排泄的影响

[目的]探讨不同规格的河蚌在不同氨氮水平下对其氨氮排泄的影响。[方法]在半现场条件下,利用静水系统研究了4种体重水平的河蚌在3个水体氨氮水平下的排泄率。试验中水温保持在24.0℃左右,颗粒悬浮物浓度维持在0.05～0.06g/L。[结果]在试验的体重和氨氮水平范围内,随着体重和外界氨氮浓度的增加,河蚌的氨氮排泄率均下降。当体重（以软组织干重计算）小于2.94g时,氨氮主效应大于体重主效应,反之,体重主效应则大于外界氨氮主效应。体重和水体氨氮水平的交互效应对氨氮排泄具有促进作用,当河蚌体重大于7.66g时,交互效应大于氨氮浓度主效应,反之,氨氮浓度主效应则大于交互效应。在该试验范围内,体重主效应大于交互效应。[结论]体重较轻的河蚌氨氮排泄率更易受到水体氨氮水平的影响。

Effects of Body Weight and Ammonia Concentration on Ammonia Excretion of Anodonta woodiana

[Objective] The aim was to study the effect of Anodonta woodiana with different specifications on ammonia nitrogen excretion under the different ammonia nitrogen levels.[Method] The excretion rate of A. woodiana with 4 body weight levels under 3 water ammonia nitrogen levels was researched by using the static water system under semi-field conditions. The water temperature was kept at about 24.0 ℃ and suspended particles concn. was maintained at 0.05-0.06 g/L in the test.[Result] In the tested range of the body weight and ammonia nitrogen level, with the rising of body weight and outside ammonia nitrogen concn. the ammonia nitrogen excretion rate of A. woodiana all were decreased. When the body weight based on soft tissue dry weight was lower than 2.94 g, the main effect of ammonia nitrogen was higher than that of the body weight, contrarily, the main effect of body weigh was higher than that of outside ammonia nitrogen. The interaction of body weight and ammonia nitrogen concn. had the promotion effect on the ammonia nitrogen excretion. When the body weight of A. woodiana was higher than 7.66 g, the interaction effect was higher than that of ammonia nitrogen concn., contrarily, the main effect of ammonia nitrogen concn. was higher than the interaction effect. The main effect of body weigh was higher than the interaction effect in the tested range.[Conclusion] The ammonia nitrogen excretion rate of A. woodiana with light of body weight was more liable to be effected by the water ammonia nitrogen level.