不同粒径与浓度的清洁疏浚物对骨条藻生长的影响

Effects of Clean Dredged Materials of Different Particle Sizes and Concentrations on Growth of Skeletonema sp.

采用室内模拟试验,研究了不同粒径、不同浓度的悬浮清洁疏浚物对骨条藻（Skeletonema sp.）生长的影响。结果表明,在96 h的试验周期里,0~16、16~63、63~88μm粒径范围的清洁疏浚物对骨条藻生长的影响极显著（P〈0.01）,而88~125μm粒径范围清洁疏浚物培养液中10 mg/L浓度组对骨条藻生长影响不显著（P〉0.05）。在相同浓度清洁疏浚物培养液中,粒径越小,对骨条藻生长影响越大;在相同粒径清洁疏浚物培养液中,浓度越高,对骨条藻生长影响越大。0~16μm粒径清洁疏浚物对骨条藻生长的96 h-EC50为2 507 mg/L,88~125μm粒径清洁疏浚物对骨条藻生长的96 h-EC50为7 645 mg/L,随着清洁疏浚物粒径范围的变大,对骨条藻生长的抑制作用逐渐减小。本试验用疏浚物为清洁疏浚物,不用考虑疏浚物本身析出的污染成分对骨条藻生长的影响,而其可能通过遮光效应引起的藻细胞光合作用减弱是对骨条藻生长产生影响的主要限制因子。

In this study , the effects of clean dredged materials of different particle sizes and concentrations on the growth of Skeletonema sp.were investigated through laboratory simulation test .The results showed that significant effects on the growth of Skeletonema sp.were displayed in the test groups of 0-16 μm, 16-63 μm, 63-88 μm particle size during the test period of 96 h(P<0.01), however, no significant effect was observed in particle size of 88-125 μm at concentration of 10 mg/L clean dredged materials groups (P>0.05).In clean dredged materi-cals of the same concentration , the smaller of particle size , the greater effects were on the growth of Skeletonema sp., while in clean dredged materials of the same particle size , the higher of concentration , the greater effects were on the growth of Skeletonema sp..96 h-EC50 of clean dredged materials of 0-16μm and 88-125μm particle size were 2 507 mg/L and 7 645 mg/L, respectively.The inhibition effect on the growth of Skeletonema sp.diminished with the increasing of particle size range .No pollution ingredients were released from the clean dredged materials in the study , indicating that the main factor of the inhibition effect was the shading effect caused by the dredged mate -rials, which resulted in algae cells photosynthesis reduced .