四种淡水贝的摄食率和耗氧率的实验研究

EXPERIMENT STUDY ON FEEDING RATES AND OXYGEN CONSUMPTION RATES OF FOUR SPECIES OF FRESHWATER MOLLUSKS

研究了4种淡水贝褶纹冠蚌、背角无齿蚌、河蚬、铜锈环棱螺的摄食率和耗氧率。摄食率的测定采用血球计数板直接计数法,耗氧率的测定采用winkler碘量法。结果表明:温度对4种贝摄食率均有显著影响,在一定的适宜温度范围内,摄食率随温度的升高而加大,到一定温度时达到最大值;以单一藻类为食时,铜锈环棱螺的摄食率最大,4种贝对栅藻和微囊藻均无选择性,其摄食率无显著性差异;当以混合藻类为食时,褶纹冠蚌、背角无齿蚌和河蚬的摄食率均大于以单一藻类为食时的摄食率,而铜锈环棱螺对微囊藻的摄食则受到了抑制。用双曲线模型OC=DO/(K1+K2×DO)评估贝类对低溶氧环境的适应能力,结果表明,铜锈环棱螺的控氧能力较强。

Feeding rates （FR） and oxygen consumption rates （OC） of Cristaria plicata, Anodonta wooodiana, Corbicula flurninea, Bellamya aeruginosa were measured. The algae cells were counted using blood cell counting chamber directly while dissolved oxygen was measured with Winkler iodic measurement. The results show that temperature has significant effect on FRs of four mollusk species and FRs reach maximum after gradually increasing at agreeable temperature. B. aeruginosahas highest FR when feeding on mono-algae, whereas four species of mollusks show no food preference. When feeding on multi-algae, FR of C. plicata, A. woodiana, and C. flurninea, increase significantly. However, the feeding on Microcystic aeruginosa of B. aeruginosa is suppressed. In order to quantify the ability of mollusks to maintain OC in low DO, hyperbolic model OC= DO/（K1＋K2 DO） was used. The higher the K1/K2value is, the stronger the oxygen control ability is. B. aeruginosa, has the highest K1/K2 value in our experiment.