除草剂阿特拉津(Atrazine)溶液中弹琴蛙蝌蚪(Rana adenopleura)的行为模式

研究了不同条件下阿特拉津溶液中 (ρ1～ 4/mgL-1:5 ,10 ,15 ,2 0 )弹琴蛙 (Ranaadenopleura)蝌蚪的行为 ,运用方差分析 (ANOVA)检验了蝌蚪在不同浓度的阿特拉津、时间段、pH值、溶氧量等条件下的行为差异性 .根据实验结果 ,确立了正常及异常行为模式 .结果表明 :在水温 (15 .0± 0 .5 )℃的条件下 ,弹琴蛙蝌蚪异常行为的出现主要与阿特拉津的浓度有关 ,同时与实验时间的长短也有一定的关系 ,而与 pH值、溶氧量关系不大 .实验组与对照组相比 ,蝌蚪出现异常行为的频次差异极显著 (P <0 .0 1) ;其中在实验组中 ,蝌蚪在 5mg/L的阿特拉津溶液中与 10mg/L、15mg/L、2 0mg/L中出现异常行为的频次差异极显著 (P <0 .0 1) ,而在 10mg/L、15mg/L、2 0mg/L阿特拉津溶液中出现异常行为的频次差异不显著 (P >0 .0 5 ) ,相关性分析表明 ,蝌蚪异常行为的出现与阿特拉津的浓度没有剂量反应关系 (r2 =0 .4 94 ) ;在对照组中 ,0 .5mL/L丙酮对照和空白对照中蝌蚪出现异常行为的频次差异不显著 (P >0 .0 5 ) .图 3表 2参 17     

除草剂阿特拉津溶液中弹琴蛙(Rana adenopleura)蝌蚪的微空间分布

采用扩散系数C等5种分布型指标测定阿特拉津溶液中(ρ1-3/mg L-1:10,20,30)弹琴蛙(Rana adenopleura)蝌蚪(均处于25期和26期,体长范围26-60 mm)在水族箱(l×b×h=40 cm×20 cm×25 cm)中的空间分布模式,结果表明蝌蚪在水族箱中为聚集分布.经多次适合性检验,证明弹琴蛙蝌蚪水族箱中的水平分布呈现负二项分布状态.随着阿特拉津浓度的升高,蝌蚪在水族箱内的聚集度(由负二项分布的k值来表明)逐渐减小(kρ1相似文献   

Ecology of Chytridiomycosis in Rainforest Stream Frog Assemblages of Tropical Queensland

Abstract:  In the wet tropics of Queensland, Australia, eight species of stream-dwelling frogs have experienced population declines. Some declines were associated with an emerging infectious disease of amphibians (chytridiomycosis) caused by the fungus Batrachochytrium dendrobatidis. We examined the spatial and temporal pattern of infection prevalence in a sample of frog populations. Infected adults and tadpoles of all species were found, and infections occurred at every site. Infection prevalence varied among species and was always < 10.0% in adults but ranged from 0.75 to 76.0% in tadpoles. In this system tadpoles and adults of some species may act as disease reservoirs, experiencing avirulent infections, whereas other hosts (declining species) experience virulent infections. Infection prevalence was higher during the cool, dry winter season (May to September) and at high elevations (600–800 m), suggesting regulation by environmental conditions, including temperature and precipitation. We found no relationships between infection prevalence and mean body condition, fluctuating asymmetry of hind limbs, population density, or the presence of metamorphosing tadpoles and juvenile frogs. Although it is not certain whether chytridiomycosis was responsible for past frog population declines in the wet tropics of Queensland, the pathogen is now endemic. Our data indicate that at the landscape level, environmental conditions have strong effects on host-pathogen dynamics. These effects interact with species-specific behavior or immune function and may be important underlying determinants of chytridiomycosis epizootics and emergence.     

硝基苯对3种中国土著水生生物的毒性

以中国林蛙(Rana chensinensis)蝌蚪、中华圆田螺(Cipangopaludina cahayensis)和日本沼虾(Macrobrachiumnipponense)3种我国代表性土著生物为对象,通过半静态试验研究了硝基苯暴露对这3种生物的急性毒性.采用美国环境保护局(USEPA)的Trimmed Spearman-Karver(TSK)法得到硝基苯的急性毒性p(96 h,LC50分别为:林蛙蝌蚪,117.04 mg·L-1;中华圆田螺,104.23 mg·L-1;日本沼虾,0.033 7 mg·L-1.基于p(96 h,LC50)值,取0.01为安全系数,安全浓度ps,分别为:林蛙蝌蚪,1.17 mg·L-1;中华圆田螺,1.04 mg·L-1;日本沼虾,0.34 μg·L-1.3种受试生物对硝基苯毒性反应的敏感性大小依次为:日本沼虾＞中华圆田螺＞林蛙蝌蚪.对照鱼类急性毒性实验的毒性分级标准,硝基苯对日本沼虾属于剧毒物质,而对林蛙蝌蚪和中华圆田螺则属于中等毒性物质.     

农药和化肥对无尾两栖类蝌蚪的毒性效应研究进展

以两栖动物研究环境污染物的毒性效应进而监测环境的变化,已成为国内外的研究热点.两栖类的胚胎发育和变态过程对水的依赖性极强,而且鳃和皮肤有很强的渗透性,当其受到污染胁迫时,在细胞、组织及生理生化水平上都会发生显著变化,进而会影响其存活和生长发育.在总结国内外相关研究基础上,综述和分析了农药、化肥(氮肥)对无尾两栖类蝌蚪的行为表现、生长发育、组织结构和生理生化变化等方面的毒性效应,以期为农药、化肥的水环境监测及合理使用提供全面的科学依据.     

Impact of environmental pollutants on vertebrate thyroid systems

甲状腺激素在脊椎动物新陈代谢、生长发育与繁殖等生理过程中起着重要的调节作用.环境污染物种类和数量不断增加,其中有很多污染物具有环境内分泌干扰的作用.甲状腺对环境污染物具有极敏感的反应,污染物不仅会引起滤泡及滤泡细胞大小、滤泡细胞数量和滤泡腔中胶质含量的改变,影响到甲状腺激素合成、分泌、转运以及代谢中多种酶的表达和活性变化,还参与和甲状腺激素的竞争性结合,进而影响到机体中由甲状腺激素调节的各项生理功能,甚至会导致机体趋于死亡.由于两栖类幼体——蝌蚪的变态发育阶段直接受到甲状腺激素的调控,现已被确认为筛选和研究环境内分泌干扰物的首选生物检测指示动物.