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   

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     

阿特拉津溶液对弹琴蛙(Rana adenopleura)蝌蚪形态发育的影响

研究了弹琴蛙(Rana adenopleura)蝌蚪在不同阿特拉津浓度(p／mg L^-1：5，10，15，20)溶液中经不同时间处理(10d、20d)后的形态发育特征．结果表明：20d处理组蝌蚪的全长增长率和后肢长增长率低于空白对照组(CKH20)，全长出现负增长，而丙酮对照组(CKacetone)蝌蚪的全长增长率高于CKH2o．实验证明，阿特拉津可抑制蝌蚪的生长和发育，而丙酮却促进蝌蚪的生长．各环境因素的多因素方差分析结果显示，pH和电导率与阿特拉津对蝌蚪的生长、发育作用效应相一致．图2表8参14     

阿特拉津对弹琴蛙(Rana adenopleura)蝌蚪微核和核异常的影响

分别在d1、d3、d7、d14,观察空白对照(CK-)、水溶助剂0.1mL/L二甲基亚砜对照(CK )、阿特拉津0.01mg/L(ρ1)、0.1mg/L(ρ2)、1mg/L(ρ3)和10mg/L(ρ4)溶液中弹琴蛙(Ranaadenopleura)蝌蚪血红细胞微核和核异常细胞数.结果表明,d14时,ρ1、ρ2、ρ3和ρ4组蝌蚪的微核率分别是CK-的2.25、2.50、4.25、5.11倍(P<0.05),说明阿特拉津可引起蝌蚪血红细胞微核率升高;且与d1、d3、d7相比较,微核率随着时间的延长有升高的趋势.d14时,ρ2、ρ3和ρ4组蝌蚪的总核异常率(含微核率)分别是CK-的2.59、2.17、1.96倍(P<0.05),说明阿特拉津也可引起蝌蚪血红细胞总核异常率升高.图2表1参17     

阿特拉津对弹琴蛙（Rana adenopleura）蝌蚪微核

分别在d1、d3、d7、d14,观察空白对照(CK-)、水溶助剂0.1mL/L二甲基亚砜对照(CK )、阿特拉津0.01mg/L(ρ1)、0.1mg/L(ρ2)、1mg/L(ρ3)和10mg/L(ρ4)溶液中弹琴蛙(Ranaadenopleura)蝌蚪血红细胞微核和核异常细胞数.结果表明,d14时,ρ1、ρ2、ρ3和ρ4组蝌蚪的微核率分别是CK-的2.25、2.50、4.25、5.11倍(P<0.05),说明阿特拉津可引起蝌蚪血红细胞微核率升高;且与d1、d3、d7相比较,微核率随着时间的延长有升高的趋势.d14时,ρ2、ρ3和ρ4组蝌蚪的总核异常率(含微核率)分别是CK-的2.59、2.17、1.96倍(P<0.05),说明阿特拉津也可引起蝌蚪血红细胞总核异常率升高.图2表1参17     

阿特拉津在天然水体沉积物中的吸附行为

本文研究了阿特拉津在几种水体沉积物中的吸附、解吸规律,并进一步探讨了沉积物浓度、pH值和离子强度对其吸附行为的影响．结果表明,不同沉积物对阿特拉津的吸附程度由沉积物本身的总有机碳、粘土矿物、阳离子交换容量、比表面积以及铁锰氧化物等理化特性综合作用的结果,有机碳不是影响阿特拉津吸附的唯一重要因素．连续吸附实验结果指出,化合物的起始浓度愈大,吸附时间愈长,阿特拉津的最大吸附容量也愈大,且在解吸过程中表现出一定的滞后性(即不可逆吸附)．沉积物浓度与其吸附量呈负相关;溶液的pH值增大,沉积物对阿特拉津吸附能力减弱;离子强度愈大,沉积物对阿特拉津吸附能力愈强．     

杀虫剂敌敌畏对黑眶蟾蜍蝌蚪的毒性影响

采用静态换水法研究了杀虫剂敌敌畏（dichlorvos，DDVP）对黑眶蟾蜍（Bufo melanostictus）蝌蚪的急性毒性和生长发育、生理活动的影响．结果表明，DDVP对黑眶蟾蜍蝌蚪的96h半数致死浓度（LC50，96h）为51．61mg／L．暴露于2．24mg／L的DDVP溶液中10d和20d，蝌蚪的体长日增长率分别降低24．9％和9．5％，并引起黑眶蟾蜍蝌蚪酯酶同工酶（EST）酶带数和强弱发生改变，抑制了蝌蚪的酯酶同工酶活性，而超氧化物歧化酶（SOD）比活受到的影响相对较小．暴露于6．72mg／L的DDVP溶液中10d和20d，蝌蚪的体长日增长率分别降低27．0％和38．8％，酯酶同工酶（EST）酶带的强弱发生明显的改变，SOD酶比活明显低于对照组．说明杀虫剂敌敌畏对黑眶蟾蜍蝌蚪可造成一定的毒性影响．图2表4参22     

阿特拉津作用下鱼食对铜绿微囊藻生长的影响及其导致的水体营养盐变化特征

养殖水域中,地表径流等可引起水域中除草剂浓度升高,抑制藻类生长,从而间接影响残饵在水体中的营养盐变化特征,威胁养殖水环境的生态平衡。为评价阿特拉津和鱼食在水环境中的生态风险,以阿特拉津质量浓度(0、5、10、20和40μg·L~(-1))及鱼食投加量(0.0500、0.2000 g;d≤0.85 mm)为变量,在以鱼食为氮磷营养源的M11培养基中,考察阿特拉津通过抑制铜铝微囊藻(Microcystis aeruginosa)生长而对水环境氮、磷营养盐浓度产生的间接影响。结果表明,无藻时,阿特拉津不能对营养盐浓度变化产生直接影响,鱼食释放正磷酸盐(PO_4~(3-)-P)和总磷(TP)浓度值均在前5天快速升高,而后缓慢增加至平衡,总氮(TN)浓度一直处于上升趋势,至45 d实验结束时,0.2000 g鱼食组PO_4~(3-)-P和TP平衡质量浓度拟合值分别为1.460 mg·L~(-1)和2.782 mg·L~(-1),TN质量浓度拟合值为3.597 mg·L~(-1)。有藻时,阿特拉津对铜绿微囊藻的抑制作用可对PO_4~(3-)-P和氨氮(NH_4~+-N)产生间接影响,阿特拉津浓度越高,藻现存量越低,水体PO_4~(3-)-P和NH_4~+-N浓度越高,"0.2000g鱼食+藻+40mg·L~(-1)阿特拉津组"和"0.2000 g鱼食+藻+0~20mg·L~(-1)阿特拉津组"在第45天时的PO_4~(3-)-P质量浓度拟合值分别为0.694 mg·L~(-1)和0.349 mg·L~(-1),而"0.200 0 g鱼食+藻+40mg·L~(-1)阿特拉津组"、"0.200 0 g鱼食+藻+20mg·L~(-1)阿特拉津组"、"0.2000 g鱼食+藻+0~10mg·L~(-1)阿特拉津组"在第45 d天的NH_4~+-N浓度拟合值分别为1.449、1.166、0.466 mg·L~(-1)。藻生长初期,藻类吸收利用PO_4~(3-)-P和NH_4~+-N较少,受鱼食释放PO_4~(3-)-P和NH_4~+-N过程的影响,PO_4~(3-)-P和NH_4~+-N浓度逐渐升高并达到最大值,但随着藻密度的升高,藻吸收利用的营养盐含量增多,PO_4~(3-)-P和NH_4~+-N浓度下降,有藻时PO_4~(3-)-P变化过程及其描述方程形式与无藻时并不一致。由于被藻类吸收利用的氮、磷营养盐可转化为细胞内氮、磷营养盐形态,有藻时,TN、TP的浓度变化趋势及其描述方程形式仍与无藻时相同。     

异噻唑啉酮类杀菌剂对黑斑蛙胚胎和蝌蚪的急性毒性

异噻唑啉酮类杀菌剂1,2-苯并异噻唑-3-酮(BIT)和甲基异噻唑啉酮(MIT)虽已在多种行业中广泛使用,但目前有关其毒性尤其对水体中生物毒性的数据还较少。鉴于BIT和MIT在水体中普遍存在,本文研究了这两种污染物对两栖动物黑斑蛙胚胎和蝌蚪的急性毒性。黑斑蛙胚胎和蝌蚪分别暴露系列浓度的BIT和MIT,观察化学品对其生长、发育和运动的影响,计算96小时半数致死浓度(96 h-LC50)和96小时半数致畸浓度(96 h-TC50),确定最小生长抑制浓度(MCIG)。结果发现,BIT对黑斑蛙胚胎的96 h-LC50和96 h-TC50分别为2.99 mg·L-1和0.60 mg·L-1,MCIG小于0.40 mg·L-1,对蝌蚪的96 h-LC50为6.44 mg·L-1。MIT对黑斑蛙胚胎的96 h-LC50和96 h-TC50分别为5.30 mg·L-1和2.36 mg·L-1,MCIG为2.59 mg·L-1,对蝌蚪的96 h-LC50为7.58 mg·L-1。根据《化学农药环境安全评价准则报批稿》中两栖动物蝌蚪急性毒性的分级标准,判定BIT和MIT的毒性等级为中等。该毒性数据可为异噻唑啉酮类杀菌剂的环境管理提供参考。     

高效液相色谱法测定水体中的阿特拉津

为建立检测水体中阿特拉津的高效液相色谱法,以ODSC18(250mm×4.6mm×5μm)柱为色谱柱,以甲醇∶水=5∶1为流动相,流速0.6mL·min-1,采用紫外检测器,用外标法测定水体中阿特拉津含量。结果表明,方法线性范围为0.052~13.0mg·L-1,线性相关系数r=0.9998;对浓度低于线性的样品,取100mL样品提取后测定,方法的检出限为0.0002mg·L-1,对含1.95μg·L-1、32.5μg·L-1、72.8μg·L-1阿特拉津水质样品进行测定,其相对标准偏差为1.61%-6.85%,加标回收率为84.6%~96.9%。采用净化方法时的加标回率为74.9%~92.9%。对阿特拉津含量在线性范围内的水样可直接过0.45μm膜后测定,加标回收率为97.0%~99.6%。该方法适用于水体中痕量和常量阿特拉津的测定。     

Wirkung von Isoproturon auf Laich und Larven zweier Unkenarten (Bombina spec.)

In intensively used arable areas, a contamination of the reproduction ponds with pesticides probably impairs the development of spawn and tadpoles of amphibians, based on the coincidental space and time. Therefore, the effects of the herbicide isoproturon (IPU) on the early life stages of the firebellied toad (Bombina bombina) and the closely related yellowbellied toad (Bombina variegata) were investigated. The results of the exposure with¹⁴C-labelled IPU (1 μg/L) indicated an uptake into the spawn and tadpoles of bothBombina species. The jelly capsules could not protect the embryo from effects of the herbicide. Tadpoles with complete opercula and without external gills were most sensitive to contamination by IPU. Physical and behavioral abnormalities of the tadpoles developed at concentrations, of 0.1 μg/L after 24 h exposure. At increasing IPU-concentrations the number of impaired and dead tadpoles increased significantly compared to the control. The enzymatic system of the Glutathion S-Transferase (GST) of theBombina tadpoles were influenced significantly by the duration and concentration of IPU exposure. Compared to the pure active ingredient IPU, the commercial herbicide TOLKAN FLO^® provoked a stronger enzymatic response in the tadpoles. This could be caused by the presence of an emulsifier used in the TOLKAN FLO^® formulation which enhanced the availability of IPU and/or the interaction between IPU and the emulsifier.     

Exposure of ground water to alachlor,atrazine and metolachlor in maize areas of ribatejo and oeste (Portugal)

In irrigated maize areas of an important Portuguese agricultural area, Ribatejo and Oeste Region, alachlor, atrazine and metolachlor were detected in ground water.

During the study performed from 1996 to 1998 atrazine was the herbicide that showed the highest frequency of detection. In the 177 ground water samples collected 62% were contaminated with atrazine, 30% with alachlor and 12% with metolachlor. All these herbicides were detected both in ground water for human consumption and for irrigation, in some cases above 0.1 ug/L. The maximum levels quantified were 13μg/L for alachlor, 30μg/L for atrazine and 56 μg/L for metolachlor.

Seasonal variation of residues in ground water it is also presented through several examples of studies performed during the period 1991–1999.     

狼尾草根系对阿特拉津长期胁迫的氧化应激响应

通过盆栽实验研究了抗性植物狼尾草根部丙二醛(MDA)、脯氨酸(Pro)、抗坏血酸(As A)含量及超氧化物歧化酶(SOD)、谷胱甘肽还原酶(GR)等氧化应激生理指标对不同浓度阿特拉津长期(48 d)胁迫的响应规律。结果表明:当阿特拉津胁迫浓度分别高于20 mg·kg~(-1)和50 mg·kg~(-1)时,狼尾草根系的MDA与Pro含量较对照组显著升高(P0.05);随着阿特拉津胁迫浓度的增加,狼尾草根部SOD和GR活性呈先升高后降低的趋势,其中当阿特拉津胁迫浓度为20 mg·kg~(-1)时,SOD和GR活性达到最大值;供试植物根系中As A含量与阿特拉津胁迫浓度呈正相关。综上,中低浓度(≤20 mg·kg~(-1))阿特拉津处理没有对狼尾草的根系产生明显的氧化胁迫效应,狼尾草根系的上述抗氧化应激生理指标对于发挥阿特拉津抗性起着重要的作用。     

New effects of Roundup on amphibians: predators reduce herbicide mortality; herbicides induce antipredator morphology

The use of pesticides is important for growing crops and protecting human health by reducing the prevalence of targeted pest species. However, less attention is given to the potential unintended effects on nontarget species, including taxonomic groups that are of current conservation concern. One issue raised in recent years is the potential for pesticides to become more lethal in the presence of predatory cues, a phenomenon observed thus far only in the laboratory. A second issue is whether pesticides can induce unintended trait changes in nontarget species, particularly trait changes that might mimic adaptive responses to natural environmental stressors. Using outdoor mesocosms, I created simple wetland communities containing leaf litter, algae, zooplankton, and three species of tadpoles (wood frogs [Rana sylvatica or Lithobates sylvaticus], leopard frogs [R. pipiens or L. pipiens], and American toads [Bufo americanus or Anaxyrus americanus]). I exposed the communities to a factorial combination of environmentally relevant herbicide concentrations (0, 1, 2, or 3 mg acid equivalents [a.e.]/L of Roundup Original MAX) crossed with three predator-cue treatments (no predators, adult newts [Notophthalmus viridescens], or larval dragonflies [Anax junius]). Without predator cues, mortality rates from Roundup were consistent with past studies. Combined with cues from the most risky predator (i.e., dragonflies), Roundup became less lethal (in direct contrast to past laboratory studies). This reduction in mortality was likely caused by the herbicide stratifying in the water column and predator cues scaring the tadpoles down to the benthos where herbicide concentrations were lower. Even more striking was the discovery that Roundup induced morphological changes in the tadpoles. In wood frog and leopard frog tadpoles, Roundup induced relatively deeper tails in the same direction and of the same magnitude as the adaptive changes induced by dragonfly cues. To my knowledge, this is the first study to show that a pesticide can induce morphological changes in a vertebrate. Moreover, the data suggest that the herbicide might be activating the tadpoles' developmental pathways used for antipredator responses. Collectively, these discoveries suggest that the world's most widely applied herbicide may have much further-reaching effects on nontarget species than previous considered.     

Acute toxicity of three avermectins to anuran tadpoles北大核心CSCD

Avermectins are a new class of macrocyclic lactones derived from mycelia of the soil actinomycete, and are among the most effective agricultural pesticides and antiparasitic agents. In this report, three avermectins (abamectin, ABM; ivermectin, IVM; and emamectin benzoate, EMB) were used to assess their toxic effects on tadpoles of four anuran species (Duttaphrynus melanostictus, Hylarana guentheri, Polypedates megacephalus and Microhyla heymonsi) using a static-renewal acute toxicity test. The results showed that there were significant dose-responsive correlations between the accumulated dead probit of tadpoles and the concentrations of the three avermectins. The 96-h half lethal concentrations (LC50) of ABM to the tadpoles of the four species were 0.042, 0.034, 0.020, and 0.014 mg/L; the 96-h LC50 values of IVM were 0.029, 0.012, 0.012, and 0.006 mg/L, and the values of EMB were 0.118, 0.111, 0.122, and 0.089 mg/L, respectively. Our study reveals that these agrochemicals probably make a significant contribution to the decline of amphibian populations, and provides valuable information about the toxic effects of avermectins on amphibians. © 2018 Science Press. All rights reserved.     

Kin preference behavior in Bufo boreas tadpoles

Summary The ontogeny of sibling recognition behavior was studied in the laboratory in tadpoles of the western toad (Bufo boreas boreas) to test the hypothesis that Bufo tadpoles associate with siblings and to compare this behavior with two species of anurans previously studied. Tadpoles reared exclusively with sibs demonstrated a preference to associate with sibs over non-sibs both early and late in development but tadpoles reared with sibs and non-sibs (mixed rearing groups) exhibited no preference. Larvae that developed a preference for sibs after being reared with them for 75 days lost this preference following exposure to a mixed group for 2 to 6 days. Additionally, larvae reared in a mixed group did not develop a preference for the familiar mixed group nor was a preference exhibited by individual larvae that were reared exclusively with 5 non-sibs. These results suggest that larvae learn by prior association to discriminate sibs from non-sibs and that preferences are rapidly modifiable following exposure to non-sibs. However, the latter two experiments suggest that social preferences are not totally labile and are not based entirely on familiarity. Field observations of larval activity, aggregation behavior, and dispersal patterns in B. boreas indicate that tadpoles mix with non-sibs from early larval stages throughout development. Because even short term exposure to nonsibs resulted in a loss of sib preference in our experiments, we suggest that a kin selection interpretation of B. boreas aggregation behavior is not parsimonious. Results differ with those of other studies of sib recognition in larval anurans.     

Removal of pesticides from water samples by adsorption with fatty acids supported on barium sulphate

Oleic or linoleic acid supported on barium sulphate was used to remove atrazine and terbuthylazine in the range of 0.1–2.0 μg/L using spiked water samples. The sorption of atrazine depends on the stirring time and the best value is 150 min. Terbuthylazine is removed well with a stirring time of 60 min and its adsorption is about 90%. Detection of the residual pesticide in treated waters, after solid phase extraction (SPE), was carried out by GC‐MS operating in selected ion monitoring (SIM) using a calibration curve by direct injection of standard solutions of herbicide.     

生物炭对土壤中阿特拉津吸附特征的影响

为探究生物炭对土壤中阿特拉津的吸附特征及影响因素,采用批处理实验研究了灭菌(T1)、5%秸秆生物炭+灭菌(T2)、未灭菌(T3)和5%秸秆生物炭+未灭菌(T4)条件下对土壤中阿特拉津吸附特征及土壤理化性质的影响.结果表明,在最初0—12 h内,不同处理下阿特拉津吸附量均随时间的延长而快速增加,而在12—96 h内增加较为缓慢并逐渐趋于平衡.在96 h时,T2和T4处理下阿特拉津最大吸附量分别达到46.22 mg·kg^-1和46.43 mg·kg^-1,而未添加生物炭的T1和T3处理则有所降低,分别为44.20 mg·kg^-1和43.09 mg·kg^-1.准二级动力学模型更好地拟合不同处理下土壤对阿特拉津吸附特征,T2和T4处理下吸附速率常数K分别为0.257 kg·mg^-1·h^-1和0.339 kg·mg^-1·h^-1,显著高于未添加生物炭处理的T1和T3处理(K分别为-0.083 kg·mg^-1·h^-1和-0.261 kg·mg^-1·h^-1).内扩散模型显示添加生物炭后,土壤对阿特拉津的吸附是一个由边界扩散、内部孔隙扩散等多因素控制的复杂化学过程.添加生物炭可显著提高土壤pH、有机碳、碱解氮、速效磷和速效钾含量,其中土壤有机碳含量与阿特拉津最大吸附量之间存在显著的正相关关系(P<0.05).由此可见,添加生物炭可以提高土壤对阿特拉津的固持能力,减少其淋溶迁移风险,从而达到修复阿特拉津污染土壤的目的.     

Herbicide exposure affects the chemical recognition of a non native predator in common toad tadpoles (<Emphasis Type="Italic">Bufo bufo</Emphasis>)

Summary. In amphibians and fishes, evidence is increasing that chemical cues from injured conspecifics can play a role in the chemical labelling and learned recognition of unfamiliar predators. In this laboratory study, we tested the prediction that prior chemical exposure to a non-native predator feeding on conspecific tadpoles will subsequently allow tadpoles of the common toad (Bufo bufo) to recognize the chemical cues specifically released by this starved predator. Furthermore, we investigated the vulnerability of this chemically-mediated process to herbicide contamination. With these aims in view, groups of tadpoles were kept either unexposed or exposed for ten days to chemical cues from Turkish crayfish (Astacus leptodactylus) previously fed on tadpoles, both in uncontaminated water and in the presence of four sublethal concentrations of amitrole (0.01, 0.1, 1 and 10 mg.l⁻¹). We then assessed the effects of the six conditioning treatments on general activity and behavioural response to chemical cues from starved crayfish. Larval treatments did not affect the general activity of the tadpoles. By contrast, the treatments had significant effects on the behavioural response to the test solution prepared form starved crayfish. The only tadpoles to show an antipredator behavioural response to the chemical stimulation from starved crayfish belonged to the groups derived from chemical exposure to tadpole-fed crayfish in uncontaminated water and in contaminated water with the lowest concentration of amitrole (0.01 mg.l⁻¹). Conversely, this chemical stimulation produced no behavioural change in the control group or in the groups derived from exposure to tadpole-fed crayfish in contaminated water containing 0.1, 1 and 10 mg.l⁻¹ of amitrole. This study demonstrates that chemical cues released during the predator’s feeding activity can subsequently be used by common toad tadpoles in the recognition of an unfamiliar predator. In addition, our results show that the presence of sublethal amitrole concentrations can impair this recognition process. Such a pesticide effect might be especially detrimental for amphibian populations threatened by invasive predators.