Pb²⁺对青蛤的急性毒性及对其血淋巴液中免疫相关酶活性的影响     

王瑞  黄雨辰  熊德东  黄亚  田甜  孟彬  梁健 《海洋科学》2020,44(3):59-65

采用静态急性毒性实验研究了重金属Pb~(2+)对青蛤(Cyclina sinensis)的生物急性毒性效应,测定了在96 h Pb~(2+)半致死浓度的1/10(TC组)和1/100(SC组)两个浓度胁迫下,血淋巴液中酸性磷酸酶(ACP)、碱性磷酸酶(AKP)和溶菌酶(LSZ)活性的变化。结果显示:Pb~(2+)的96 h LC50为7.938 mg/L; SC组ACP活性表现为诱导-抑制趋势,除4 d外均与对照组差异显著(P0.05), TC组为抑制趋势,为3个组中的最低,与对照组差异显著(P0.05);实验组SC组和TC组的AKP、LSZ活性均表现为前期为诱导中后期受抑制的趋势,与对照组差异显著(P0.05),且TC组活性始终低于SC组,表现出Pb~(2+)的胁迫浓度越高酶活性受到的抑制作用越大。以上结果表明,重金属Pb~(2+)对青蛤的毒性级别为高毒级,能造成青蛤免疫相关酶的活性受到抑制,影响青蛤的免疫能力,而且这种抑制作用随着环境中Pb~(2+)浓度增加而增加。  相似文献   

重金属锌,铅对菲律宾蛤仔的急性毒性试验   总被引：14，自引：1，他引：14  

刘琼玉  洪华生 《台湾海峡》1997,16(1):50-54

本文研究了必需元素Ｚｎ及非必需元素Ｐｂ对菲律宾蛤仔的急性毒性作用，得到Ｚｎ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为１４７．９１、１６．４０ｍｇ／ｄｍ＾３；Ｐｂ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为３１．６２、１４．２８ｍｇ／ｄｍ＾３。估算得到Ｚｎ、Ｐｂ对菲律宾蛤仔的安全浓度分别为０．８２、０．７１ｍｇ／ｄｍ＾３。  相似文献   

转炉钢渣对两种对虾幼虾的急性毒性效应     

许刚  宋秀贤  刘云  董晓丹  俞志明 《海洋科学》2007,31(8):76-79

初步研究了一定粒径的转炉钢渣对日本对虾（Penaeus japonicus）幼虾和中国明对虾（fenneropenaeus chinensis）幼虾的急性毒性效应。实验结果显示，当钢渣质量浓度为1.8g／L时，日本对虾幼虾96h的最高死亡率为33．33％；随着钢渣质量浓度的增加，死亡率增高；当钢渣质量浓度为18g／L时，其96h的最大死亡率达到了75％。相对于日本对虾幼虾，钢渣质量浓度为18g／L时中国明对虾幼虾96h的最高死亡率只有36．67％。运用直线内插法求出钢渣对日本对虾幼虾96h半致死浓度为1．62g／L，钢渣对日本对虾的安全浓度为0．162g／L，而在实验条件下中国明对虾幼虾的半致死浓度要明显高于日本对虾幼虾。  相似文献   

四种重金属对刺参幼参的急性致毒效应   总被引：1，自引：0，他引：1  

孙振兴  陈书秀  陈静  高洪梅  李丹 《海洋通报》2007,26(5):80-85

采用静水试验法,在水温18.5℃~20℃的条件下,用Cu2 ,Zn2 ,Cd2 和Cr6 四种重金属对刺参幼参进行了单一急性毒性试验。结果表明:Cu2 对刺参幼参的24h,48h,72h和96hLC50分别为0.299,0.176,0.133和0.120mg/L;Zn2 的24h,48h,72h和96hLC50分别为6.700,3.624,2.577和1.951mg/L;Cd2 的24h,48h和72hLC50分别为4.246,2.588和2.137mg/L;Cr6 的24h,48h和72hLC50分别为31.974,7.499和3.808mg/L;Cu2 ,Zn2 ,Cd2 和Cr6 对刺参幼参的安全浓度分别为0.018,0.362,0.259和0.750mg/L。四种重金属对刺参幼参的毒性大小依次为Cu2 >Cd2 >Zn2 >Cr6 。  相似文献   

Effects of heavy metals on the survival ofDiacypris compacta (Herbst) (Ostracoda) from the Coorong,South Australia     

Anna Brooks  Rehema M. White  David C. Paton 《International Journal of Salt Lake Research》1995,4(2):133-163

The hypermarine southern Coorong is threatened by proposals to drain relatively fresh surface water and groundwater from adjacent agricultural areas into the Coorong. These influent waters carry moderate loads of heavy metals. Acute toxicity of heavy metals toDiacypris compacta, an abundant ostracod in the Coorong, was measured in the laboratory at 18°C in a static system using Coorong water (pH 7.8 salinity 50 ppt). At 4 days (96 h) the mean values of LC₅₀ for copper, zinc, lead and, cadmium respectively were 0.8, 2.1, 3.1 and 4.3 mg L^–1, and at 8 days the respective mean LC₅₀ s were 0.4, 0.7, 2.2 and 1.1 mgL^–1. The effect of two or three metals on mortality was additive in some cases and synergistic in other cases, but generally less than additive. However, in all cases mortality was greater in the presence of two or three metals than in the presence of a single metal. According to ANZECC (1992) guidelines, maximum acceptable concentrations of heavy metals should be no higher than 0.01 x the lowest LC₅₀ value. Using the lowest LC₅₀ values forDiacypris compacta obtained at 8 days, maximum acceptable concentrations in the Coorong would be 4, 5, 9 and 22 gL^–1 for copper, zinc, cadmium and lead respectively, the values for zinc and copper failling below those recommended by ANZECC (1992) for marine waters. Reported concentrations of copper and zinc in surface water and groundwater in areas adjacent to the Coorong sometimes exceed these values, hence drainage of these waters into the Coorong represents a significant hazard to the Coorong biota.  相似文献   

顾及拓扑与尖角的分类矢量数据分组压缩算法   总被引：1，自引：1，他引：0  

宋正祥  周晓光  陈律余 《测绘科学》2016,41(11):98-103

针对现有拆分重组法对存在复杂内环以及复杂相交岛屿多边形的分类矢量数据的压缩结果中包含裂缝、重叠及大量尖锐夹角的问题,提出了一种顾及拓扑一致性与尖角的分组压缩方法。依据分类矢量数据中多边形与多边形及其内环的相交关系对矢量矢量数据分组,以修正后拆分重组法结合直接分割法和间接分割法对分类矢量数据分组压缩,压缩结果中不存在裂缝与重叠现象,维护了分类矢量数据的拓扑一致性;通过取回尖角点前后被删除的点,解决了压缩结果中尖角过多的问题。以Landsat8遥感影像分类矢量数据实验验证了文章算法,并与直接分割法、间接分割法、拆分重组法进行了对比分析,验证了本文方法的有效性。  相似文献   

A homogeneous model of the Deacon cell in a circumpolar ocean     

Liping Wang  Rui Xin Huang 《Dynamics of Atmospheres and Oceans》1998,28(3-4)

Dynamics of the three-dimensional structure of the wind-driven Deacon cell in a β-plane channel are discussed in a homogeneous model in the presence of a sufficiently high ridge. The emphasis is on the water mass balance: how the northward surface Ekman drift is returned. It is demonstrated that a sufficiently high ridge can break up the geostrophic constraint and a net geostrophic volume flux across the open latitude band is allowed. It is found that: (1) the Deacon cell is a fundamentally three-dimensional structure, (2) wind forcing can drive an inter-basin water mass exchange in the Southern Ocean, and (3) zonal through-channel transport in the circumpolar ocean varies at different longitudes.  相似文献   

Effect of land–ocean contrast on the structure of anomaly tropical circulation     

Binson Joseph  Prashant Goswami 《Dynamics of Atmospheres and Oceans》1998,28(3-4)

While the important role of land–ocean contrast (LOC) in the mean atmospheric circulation is well-known, an intriguing question remains as to whether LOC can also significantly influence the anomaly circulation. This question is particularly important in the tropics, where a large part of the variabilities is known to be due to convective internal dynamics, which in turn can be significantly affected by LOC. In the present work, we investigate this question using a model of convectively driven anomaly circulation in the tropics. Emphasizing the lower tropospheric flow, we adopt a model describing the horizontal dynamics of the first baroclinic mode on an equatorial β-plane, in the presence of moist feedbacks. We introduce LOC in both latitudinal and longitudinal directions. Land surface dryness is taken into account in the moisture budget through the control of evaporative flux. A constant non-latent heating term is used over land in order to represent radiative and sensible heating effects. First, a control run is performed, numerically, without any LOC using random initial perturbations. The gravest mode that emerges from the control run, which is a wave-2 feature with a period around 20 days, is then used as the initial field for the model runs with LOC. The results show that LOC can significantly influence even the tropical variabilities. A latitudinal LOC, with a land mass in the northern hemisphere (north of 10°N), tends to shift the region of maximum precipitation slightly north of the equator with accompanying steeper gradients near the land–ocean boundary. The implications of this result for our understanding of Asian summer monsoon conditions are discussed. When LOC is only in the longitudinal direction, the dominant wave structure that emerges from the model run has wavenumber one and a period of about 35 days, very similar to the observed 30–60 day oscillation. In our final experiment, which is nearer to the realistic land–ocean configuration in the tropics, it is found that both latitudinal and longitudinal effects of LOC are important aspects of the tropical anomaly circulation. It is suggested that some of the patterns in the precipitation distribution, observed in the tropics and simulated using general circulation models are results of convectively induced internal dynamics, modulated by LOC.  相似文献   

The transmission of spatially-compact internal wave packets through a critical level     

A. Javam  L. G. Redekopp   《Dynamics of Atmospheres and Oceans》1998,28(3-4)

Results are presented from numerical simulations of the incidence of a spatially-compact beam of internal waves on a shear layer containing a critical level. It is found that a significant fraction of the energy of the incident beam is transmitted across the critical level when the packet is narrow in physical space and when the energy density of the packet is not too high so that nonlinear effects are weak. As either the packet width or its energy density increases, the presence of a critical level renders the shear layer increasingly opaque to the transmission of energy. The familiar exponentially small value of the transmission coefficient is recovered as the spatial width of the packet exceeds (roughly) eight to ten wave lengths.  相似文献   

Cu²⁺对青蛤的胁迫效应     

梁健  雷雅雲  李永仁  郭永军  邢克智 《海洋科学》2015,39(11):74-78

为研究青蛤(Cyclina sinensis)对重金属Cu~(2+)的蓄积作用及免疫机能的影响,开展了Cu~(2+)对青蛤的急性毒性实验,观察青蛤在96 h Cu~(2+)半致死浓度和安全浓度胁迫下,不同组织的蓄积趋势,及血淋巴液中SOD、CAT和ACP活性的变化。结果显示:Cu~(2+)的半致死浓度为0.807 mg/L,安全浓度为0.00807 mg/L。鳃和内脏团组织中蓄积的Cu~(2+)浓度与处理时间呈正相关;在半致死和安全浓度胁迫下,鳃组织中Cu~(2+)蓄积速度均快于内脏团;在半致死浓度胁迫下血淋巴液中SOD、CAT和ACP活性呈现先诱导再抑制的趋势,安全浓度下无明显变化,但均高于对照组水平。  相似文献