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1.
铜和汞对蝌蚪联合毒性的影响 总被引：13，自引：0，他引：13
研究了铜和汞共存对泽蛙蝌蚪的联合毒性。Cu^2 对泽蛙蝌蚪的24h、48h、96h的半致死浓度分别为0．201、0．138和0．118mg.L^-1，Hg^2 对泽蛙蝌蚪的24h、48h、96h的LC50分别为0．135、0．112和0．103mg.L^-1。Cu^2 和Hg^2 共存对蝌蚪联合毒性的24h、48h和96h的相加指数AI分别为0．082、0．166和0．322，皆大零，表现为协同作用。 相似文献
2.
通过实验室水培试验研究不同浓度处理水平下Cu、Cd、As单一及其复合污染对紫背浮萍叶绿素和丙二醛浓度的影响结果表明,同一浓度处理水平下,单一重金属污染对浮萍叶绿素的生态毒性效应为Cd>Cu>As,对丙二醛的生态毒性效应为Cd≈As>Cu。与单一污染相比,As Cd和Cu Cd复合污染对浮萍叶绿素毒性增强,表现为协同作用,加强了对浮萍叶细胞的伤害;而As Cu和As Cu Cd复合污染对叶绿素联合毒性作用趋向于毒性减少的拮抗作用。复合污染对浮萍丙二醛的生态毒性效应情况则较复杂,除As Cd外其余3种复合污染组合对浮萍细胞膜均有一定增透作用。 相似文献
3.
试验研究铜、镉对蝌蚪的急性毒性和联合毒性结果表明,Cu~(2 )对蝌蚪24h、48h、96h的半致死浓度LC_(50)分别为0.201mgg/kg、0.138mg/kg和0.118mg/kg,Cd~(2 )对蝌蚪24h、48h和96h的LC_(50)分别为32.1mg/kg、23.3mg/kg和18.9mg/kg。Cu~(2 )和Cd~(2 )共存对蝌蚪24h、48h和96h联合毒性的相加指数AI分别为1.03、1.2和1.20,均为协同作用。 相似文献
4.
以赤子爱胜蚓(Eisenia fetida)为试验动物, 选取氯化镉、马拉硫磷和乙草胺作为污染物, 通过人工土壤法研究了3种污染物在5种比例两种污染物复合条件下对蚯蚓的急性毒性。研究结果表明, 3种污染物在两两复合污染时的作用类型以拮抗为主, 仅在镉浓度19.46 mg·kg-1和乙草胺175.15 mg·kg-1 (1︰9)复合类型是相加作用, 说明复合污染生态毒理效应与污染物的化学性质和浓度水平均相关。从蚯蚓活体体重减少情况看, 在复合污染条件下, 污染物对蚯蚓生长的影响与单一污染的结果类似, 马拉硫磷对赤子爱胜蚓的影响最大, 乙草胺次之, 而氯化镉的影响最小。 相似文献
5.
为解决乙草胺残留问题,采用连续传代富集培养的方法,从长期生产乙草胺的农药厂污染土壤中分离筛选到1株乙草胺降解菌株AC-1。经过形态学特征、生理生化特征和16S rRNA基因序列系统发育分析,菌株AC-1被鉴定为红球菌属(Rhodococcus)。菌株AC-1在48h内能将0.2 m M的乙草胺完全降解,但不能矿化乙草胺。借助LC-MS,确定乙草胺降解终产物为2-氯-N-(2-乙基-6-甲基苯基)乙酰胺(CMEPA)。菌株AC-1降解乙草胺的最适温度为30℃,最适p H值为7.5。0.1 m M的Cu2+和Hg2+对菌株AC-1降解乙草胺具有很强的抑制作用,而0.1 m M的Fe2+则对菌株AC-1降解乙草胺具有微弱的促进作用。菌株AC-1对乙草胺的降解效果与起始接种量呈正相关。菌株AC-1对甲草胺和丁草胺表现出良好的降解效果,但对异丙甲草胺的降解能力非常微弱。土壤降解试验表明,投加菌株AC-1可以明显促进土壤中乙草胺的降解。本研究为乙草胺的有效降解提供了数据和技术支持。 相似文献
6.
通过模拟土壤溶液进行水培试验,研究了锌（Zn）对大麦（Hordeum Vulgate）镉（Cd）、铜（Cu）毒性的影响,以及Zn-Cd和Zn-Cu的联合毒性效应。结果表明：Zn、Cd和Cu单独作用于大麦时,EC。分别为78．01、2．98、0．64μmol·L^-1,Zn的毒性远远小于Cd和Cu。在Zn-Cd混合体系中,当Zn浓度低于5μmol·L^-1时,随着溶液中Zn浓度的增加,EC50（Cd）呈显著的线性增加,表明低浓度Zn对大麦Cd毒性具有抑制作用;利用毒性单位（TU）模型计算了Zn-Cd混合体系的TUmix值,结果显示TUtax≥1TU,且Tu。随Zn浓度的升高而增加,表明Zn、Cd联合作用于大麦时主要表现为拮抗作用,且这种作用和混合体系中Zn的比例有关。在Zn-Cu混合体系中,随着Zn浓度的增加,大麦相对根长（RE）明显减小,EC50（Cu）逐渐降低,表明Zn增强了大麦Cu的毒性;Zn-Cu的Tumix。均小于1TU,Zn、Cu联合作用于大麦时表现为协同毒性作用。 相似文献
7.
采用室内培养实验方法,研究了沉水植物轮叶黑藻（Hydilla verticillata）和穗花狐尾藻（Myriophyllum spicatum）在吸收铜离子过程中产生的生理反应。以上两种沉水植物在Cu2＋浓度分别为0、2、4、8、16、32、64mg·L-1的溶液中暴露了24、48、72、96h,结果表明：黑藻对铜的积累量明显高于狐尾藻对铜的积累量,本实验中黑藻对铜的最大积累量为11295．31μgCu·g-1（干重）,而狐尾藻对铜的最大积累量为6861．26μgCu·g-1（于重）;对以上两种植物的叶绿素含量、SOD和POD活性产生胁迫效应的Cu2＋浓度明显不同,表明狐尾藻较黑藻对重金属Cu2＋胁迫具有更高的耐受性。以上研究结果对利用沉水植物去除重金属污染能起到一定的指导和参考作用。 相似文献
8.
采用静态试验法,将鲫鱼暴露于4、16、64mg·L^-1洛克沙胂中48、96、144h后,检测了鱼鳃、肾脏和肝的Na^＋-K^＋-ATP酶活性。结果表明,在同一组织中,随着处理浓度的提高,洛克沙胂对鲫鱼各组织Na^＋-K^＋-ATP酶活性抑制作用增强。对于不同组织,同一处理浓度的洛克沙胂对鲫鱼鳃中Na^＋-K^＋-ATP酶活性抑制作用更为明显,其次是肝和肾（P〈0．01）。在同一浓度下,洛克沙胂对鲫鱼各组织Na^＋-K^＋-ATP酶活性抑制率呈明显的时间-效应关系,暴露时间越长,抑制率越高（P〈0．01）。此外,单细胞凝胶电泳试验（SCGE）结果表明,鲫鱼暴露于0．5、1、2mg·L^-1洛克沙胂中72h能引起鲫鱼肾细胞明显的DNA损伤,并在设定剂量范围内呈现一定的剂量-效应关系;同时,鲫鱼肾细胞于体外暴露于1、10、100、500、1000mg·L^-1洛克沙胂3、6、12h后,可引起严重的DNA损伤。 相似文献
9.
《农业环境与发展》2020,(1)
为分析抗生素与重金属单一及复合污染对土壤过氧化氢酶活性的影响,以三种兽用抗生素恩诺沙星(Enrofloxacin,ENR)、土霉素(Oxytetracycline,OTC)、磺胺二甲嘧啶(Sulfamethazine,SM2)和重金属铜(Cu)为目标污染物,采用高锰酸钾滴定法,研究其对土壤中过氧化氢酶活性的影响。结果表明,单一污染下,中低浓度的ENR各处理对酶活性有一定激活作用,最大激活率为5.52%;OTC处理组随着污染物浓度的增加,对酶活性的抑制作用增大,抑制率最大为8.36%;SM2处理初期,中低浓度处理组对酶有激活作用,最大激活率为7.46%,处理21 d,高浓度处理组对酶活性有显著促进作用,激活率为1.71%。Cu在第28 d时对过氧化氢酶活性表现为抑制。复合污染下,ENR与Cu复合污染组对过氧化氢酶活性的影响随污染浓度增加先抑制后激活;OTC与Cu处理第7 d,各浓度组与对照差异均不显著,14 d后,高浓度组产生抑制作用,抑制率最高为3.58%;SM2与Cu高浓度处理组在第7 d对土壤过氧化氢酶活性表现为明显激活作用,激活率高达10.00%,14 d后转为抑制作用,28 d时抑制率最高为4.49%。研究表明,单一污染下,抗生素对土壤过氧化氢酶的影响与其类型、暴露浓度以及暴露时间有关。复合污染下,抗生素和Cu的交互作用存在差异,表现为拮抗和协同两种作用,不仅与抗生素种类、复合污染浓度比例、暴露时间有关,还与抗生素和Cu配位反应产生复合物的比例有关。 相似文献
10.
浮萍对稻田田面水中氮素转化与可溶性氮的影响 总被引：1，自引：0，他引：1
浮萍是稻田田面水中大量存在的典型水生植物，本试验采用室内培养的方法，以采自浙江省嘉兴市双桥农场的青紫泥水稻土为例，探讨了不同初始密度的浮萍对稻田施尿素后田面水尿素水解及可溶性氮浓度的影响。结果表明，浮萍可明显加快田面水尿素态氮的水解过程，对照、低浓度浮萍（D1）和高浓度浮萍（D2）处理中尿素水解速率常数k分别为0．02，0．03，0、04／h；试验前期，浮萍将大量的铵态氮（NH4^＋-N）吸收同化后储存于体内．而从第12天（D2处理）和15天（D1处理）开始，由于浮萍的释氮作用导致田面水中NH4^＋-N浓度逐步回升，同时硝态氮（NO3^--N）浓度也明显增加，说明浮萍在田面水氮索浓度较高时可大量积累氮索而浓度较低时可以向田面水中释放氮素，这有利于降低施肥初期田面水氮素流失潜能和保证施肥后期作物的氮营养供应。 相似文献
11.
Yong‐Hua Yang Shan‐Min Chen Zhe Chen Hong‐Yan Zhang Heng‐Guan Shen Zi‐Chun Hua 《Journal of plant nutrition》2013,36(4-5):693-700
The effects of silicon (Si) on the toxicity of aluminum (Al) to mungbean (Phaseolus aureus Roxb.) seedlings were studied in a growth chamber. Mungbean seedlings were grown in a nutrient solution with combinations of three concentrations of Si (0,1, and 10 mM) and three concentrations of Al (0, 2, and 5 mM) in randomized completely block design experiments for 16 days. Silicon at 1 mM in the solution decreased root length, fresh and dry weights, and chlorophyll content, and showed no significant effect on epicotyl length and seedling height, and protein contents of shoots or roots in mungbean seedling under no Al stress. But, Si at 10 mM showed marked toxic effects on mungbean seedling growth and increased protein contents of the shoots or roots. In contrast, under 2 mM Al stress, Si addition at 1 mM had significant increasing effect on root length, fresh and dry weights, and chlorophyll content. It also had decreasing effect on protein contents of the shoots or roots, and had no effect on epicotyl length and seedling height. Silicon addition at 10 mM showed no effect on morphological and physiological measurements of mungbean seedling. However, Si at 1 mM added to solution only increased seedling height, epicotyl length, fresh weight, and chlorophyll content, but decreased dry weight and protein content of the roots under 5 mM Al stress, significantly. Silicon addition at 10 mM showed similar toxic effects on mungbean seedling growth under 5 mM Al stress to that under no Al stress. 相似文献
12.
Using plate counting and ergosterol assay, single and joint effects of acetochlor and methamidophos on the dynamics of soil fungal population and total fungal biomass in the black soil zone of Northeast China were investigated. The results demonstrated that acetochlor at high concentration levels （150 and 250 mg kg^-1） had an acute and mostly chronic toxicity on both the soil fungal population and total fungal biomass, but at a low concentration （50 mg kg^-1） generally had a stimulating effect that was stronger with total fungal biomass than with the soil fungal population. Methamidophos at a high concentration level （250 mg kg^-1） alone and almost all of its combinations with various dosages of acetochlor increased the soil fungal population, whereas at most sampling dates with 250 mg methamidophos kg^-1 soil, total fungal biomass increased, but in combination with acetochlor it was decreased in the early period of incubation and then increased 28 days after incubation. Thus, through measuring the number of colony forming unit of the soil fungal population along with the total fungal biomass, a better understanding on effects of agrochemicals on soil fungi could be made. 相似文献
13.
Yong-Hua Yang Hai-Jin Gu Wen-Yi Fan Bilkisu A. Abdullahi 《Water, air, and soil pollution》2004,154(1-4):239-248
Boron (B) is an essential micronutrient for higher plants. It has been suggested that addition of B at an optimal concentration might alleviate Al toxicity. Little information is available about B effects on soybean seedling growth under Al stress and differential alleviation of B on Al toxicity. In the present study, the seedlings of two soybean cultivars (Williams and Nanrong 73-935) were grown in a solution with factorial combinations of Al (0, 2, and 5 mM) and B (0, 5, and 50 μM) in a randomized complete block design experiment for 18 days. The results showed that high B was found to ameliorate Al toxicity by significantly increasing the growth characters including root length under 2 mM Al stress, and epicotyl length and fresh weight under 5 mM Al stress of the two cultivars. However, high B concentration did not significantly increase chlorophyll content under Al stress. Williams was more sensitive than Nanrong 73-935 on the growth characters and chlorophyll content under double stresses (B deficiency combined with Al toxicity), although they had similar sensitivity to B deficiency stress alone for growth characters. In addition, high B concentration was found to cause toxicity symptoms on root length and older leaves of both cultivars under no Al stress. 相似文献
14.
Boron (B) amelioration of aluminum (Al) toxicity was studied for growth of mungbean (Phaseolus aureus Roxb.) seedlings and cuttings (without roots) in a growth chamber. Mungbean seedlings and cuttings were grown in the solution with combinations of three concentrations of B (0,5, and 50 μM) and three concentrations of Al (0, 2, and 5 mM) in randomized complete block design experiments for 16 days. Results showed that B significantly promoted elongation of epicotyls and hypocotyls, and increased height of seedlings grown under Al stress. Boron also increased fresh weight of seedlings in high Al solution. Treatment of plants grown with high B and Al stress had no apparent effect on fresh and dry weights of seedling roots. Seedling dry weight increased significantly by adding high B to solutions with 2 mM or 5 mM Al. No significant differences were observed between the high B treatment and the control (normal B, 5 μM) in lengths of epicotyls and fresh and dry weights of mungbean cuttings grown under Al stress. High concentrations of B decreased soluble protein and increased chlorophyll in seedlings treated with 2 mM Al. Boron had no amelioration effect on cuttings grown with Al, although Al increased soluble protein. Our results suggested that B alleviation of Al toxicity was related to root function and Al toxicity may possibly be due, in part, to B deficiency. 相似文献
15.
Hugh Frick 《Journal of plant nutrition》2013,36(12):1131-1145
Vegetative growth of the aquatic monocotyledon Lemna minor L. (duckweed) under continuous irradiation in photoheterotrophic medium is log‐linear with a frond doubling‐time of about 1.4 d. This steady‐state frond multiplication rate was not altered (through six days) by concentrations of micronutrients (Fe,Mn,B,Cu, Zn,Mo) between 28 and 1000 times that contained in the routine growth medium. Using high but not inhibitory concentrations, the effect on steady‐state growth of all possible 2‐, 3‐, 4‐, 5‐, and 6‐way combinations has been studied. Lerma growing in the presence of high concentrations of any other micronutrient is least tolerant to the addition of Mo. Growth inhibition due to 2‐way combinations of certain elements (eg. MnMo) was prevented by the presence of a third (eg. MnMoZn) in patterns suggesting selective interaction between the elements. Moreover, in the absence of Mo in high concentration the combination of the other 5 micronutrients was not inhibitory even though separate 2‐, 3‐, and 4‐way combinations were.
The accumulation of micronutrients during steady‐state growth showed that each was absorbed against a chemical gradient at high external concentration (no data for B). In the absence of growth inhibition, Fe accumulated to 65 μg/g fresh weight, Mn to 221, Cu to 40, Zn to 139, and Mo to 705. Multiplying each by approximately 8 converts to μg/g dry weight. 相似文献
16.
《Communications in Soil Science and Plant Analysis》2012,43(13-14):2069-2076
Abstract To identify the detrimental effects of excess copper in radish (Raphanus sativus) cv. Jaunpuri, plants were grown in refined sand at control (0.001) and 0.1 and 0.2 mM (excess) copper (Cu) supplied as Cu sulphate. Previously plants were maintained for 24 days in complete nutrient solution and on the 25th day, excess Cu was superimposed. After 6 days of metal supply, the visible effects of excess Cu appeared as retardation in growth and interveinal chlorosis of young leaves; chlorosis intensified later with the development of irregular brown spots on lamina. Excess Cu not only reduced the size of leaves but also affected adversely the root development. In radish, Cu toxicity decreased the fresh weight, biomass, root weight, concentrations of total and active iron, chlorophyll, activities of antioxidative enzymes catalase (CAT), and peroxidase (POX), starch phosphorylase (ST) and acid phosphatase (AP) with concomitant increase in Cu accumulation in different parts. These effects were more pronounced at 0.2 than 0.1 mM Cu. 相似文献
17.
农田黑土中不同浓度乙草胺对玉米苗期生长的影响 总被引：1，自引：0，他引：1
通过黑土盆栽试验研究了施用化肥条件下不同浓度乙草胺对玉米苗期生长的影响。结果表明,虽然在整个取样期间,植株体内无乙草胺残留检出,但是乙草胺施用对玉米苗期的形态和生理指标均具有一定影响。植株中超氧化物歧化酶活性、地下部分过氧化物酶活性和株高、根长等形态指标在玉米生长前期发生明显变化,其变化趋势受到乙草胺施用量的显著影响。在施有等量化肥的条件下,低浓度和高浓度乙草胺的施用抑制了玉米的生长,但中等浓度乙草胺对苗期玉米的生长表现出一定的促进作用。随着种植时间的延长,乙草胺活性降低,植物体的各项抗性指标和生理指标趋于一致。 相似文献
18.
S. R. Verma Sarita Rani S. K. Bansal R. C. Dalela 《Water, air, and soil pollution》1980,13(2):229-234
A quantitative index of synergism, antagonism and additivity has been measured experimentally in the fishMystus vittatus for three pesticides viz. Thiotox (Endosulfan) (T), Dichlorvos (D) and Carbofuran (C). For a combination of two pesticides, the dose of the one pesticide of a pair was fixed at the no-effect level while the dose of the second pesticide was increased until the entire dose response curve was obtained. To evaluate interactions of three pesticides, the previous pair of pesticides was kept fixed at their combined TLO level, and the third pesticide was increased and again a dose-response curve was obtained. From the results obtained, it is shown that a particular combination could be synergistic, antagonistic or additive, depending on the relative doses employed. In the present study (T + D)/C combination was most synergistic (toxic) in nature while D/T and C/T were least toxic or antagonistic in their effects. However, T/D, (C + T)/D, C/D and D/C combinations were additive in nature. (D + T)/C, (D + C)/T, (T + C)/D and (C + D)/T combinations were found less synergistic in nature than (T + D)/C. 相似文献
19.
V. Uma Devi 《Water, air, and soil pollution》1995,81(3-4):295-304
Zinc (Zn) toxicity to a marine fouling dreissinid bivalveMytilopsis sallei was investigated and the safe concentration of Zn was determined for this bivalve. In acute toxicity tests onM. sallei the 96 h LC50 value for Zn is found to be 8.364 mg 1?1. The results suggest that Zn has the lowest toxic effect onM. sallei when compared to copper and mercury. Effect of Zn on the oxygen consumption ofM. sallei was studied. Sub-lethal concentrations of Zn functioned as respiratory depressants. Accumulation of Zn was investigated in relation to exposure period and concentration inM. sallei. Zn accumulation was found to be sensitive to both concentration of Zn and exposure time. The effect of exposure time and concentration on body biochemical components was also studied inM. sallei. This accumulated Zn has resulted in impairment of carbohydrate metabolism and protein utilisation. 相似文献