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31.

To examine pesticide mixture toxicity to aqueous organisms, we assessed the single and combined toxicities of thiamethoxam and other four pesticides (chlorpyrifos, beta-cypermethrin, tetraconazole, and azoxystrobin) to the rare minnow (Gobiocypris rarus). Data from 96-h semi-static toxicity assays of various developmental phases (embryonic, larval, juvenile, and adult phases) showed that beta-cypermethrin, chlorpyrifos, and azoxystrobin had the highest toxicities to G. rarus, and their LC50 values ranged from 0.0031 to 0.86 mg a.i. L?1, from 0.016 to 6.38 mg a.i. L?1, and from 0.39 to 1.08 mg a.i. L?1, respectively. Tetraconazole displayed a comparatively high toxicity, and its LC50 values ranged from 3.48 to 16.73 mg a.i. L?1. By contrast, thiamethoxam exhibited the lowest toxic effect with LC50 values ranging from 37.85 to 351.9 mg a.i. L?1. Rare minnow larvae were more sensitive than embryos to all the pesticides tested. Our data showed that a pesticide mixture of thiamethoxam–tetraconazole elicited synergetic toxicity to G. rarus. Moreover, pesticide mixtures containing beta-cypermethrin in combination with chlorpyrifos or tetraconazole also had synergetic toxicities to fish. The majority of pesticides are presumed to have additive toxicity, while our data emphasized that the concurrent existence of some chemicals in the aqueous circumstance could cause synergetic toxic effect, leading to severe loss to the aqueous environments in comparison with their single toxicities. Thence, the synergetic impacts of chemical mixtures should be considered when assessing the ecological risk of chemicals.

  相似文献   
32.
Environmental Science and Pollution Research - With the increasingly serious pollution of plastics, biodegradable plastics (BDPs) have attracted attention as a new material that can replace...  相似文献   
33.
Environmental Science and Pollution Research - The red-crowned crane (Grus japonensis) is an endangered bird species that has been listed as one of the Class I National Key Protected Wild Animals...  相似文献   
34.
Environmental Science and Pollution Research - This study reports how adding a membrane filter (0.45-μm cellulose nitrate filter) between a glass fibre filter and the solid phase extraction...  相似文献   
35.
陆之洋 《环保科技》2014,20(5):29-31,51
发展电动汽车是落实我国"节能减排"产业政策的重要举措。电动汽车充电设施是电动汽车发展的基础,其规划将直接影响电动汽车的可持续发展。针对三线城市的特点,从充电方式和电动汽车接入对电网的影响出发,确定了三线城市电动汽车充电设施的规划原则、流程和阶段。  相似文献   
36.
Journal of Material Cycles and Waste Management - This study aimed at investigating the impacts of different percentages of biochar (BC) (at 0, 15, and 25%; by vol.) and/or cattle manure (CM) (at...  相似文献   
37.
This study investigated crystallization mechanisms for the formation of lead aluminosilicate by sintering lead stabilization with kaolin-based precursors. PbAl2Si2O8 was found to be the only stable lead aluminosilicate in low-PbO system and demonstrates its highly intrinsic resistance to acid attack in leaching test. A three-stage PbAl2Si2O8 formation mechanism was supported by the results of the changing temperature in the system. Amorphization of sintered products was observed in both PbO/kaolinite and PbO/mullite systems at 600–700°C. When the temperature was increased to 750–900°C, the crystallochemical formation of lead aluminosilicates (i.e., Pb4Al4Si3O16, Pb6Al6Si2O21, and PbAl2Si2O8) was observed. Pb4Al4Si3O16 and Pb6Al6Si2O21 were found to be the intermediate phases at 700–900°C. Finally, PbAl2Si2O8 was found to be the only crystallite phase to host Pb at above 950°C. A maximum of 80% and 96.7% Pb can be incorporated into PbAl2Si2O8 in PbO/kaolinite and PbO/mullite systems, respectively, but the final products exhibited different microstructures. To reduce environmental hazard of lead, this strategy demonstrated a preferred mechanism of immobilizing lead into PbAl2Si2O8 structure via kaolin-based precursors.  相似文献   
38.
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and...  相似文献   
39.
砒砂岩区不同留茬高度及坡向下沙棘根系分形特征   总被引:1,自引:0,他引:1  
为提高内蒙古砒砂岩区沙棘(Hippophae rhamnoides)人工林根系的生长能力,对东(E)、南(S)、西(W)、北(N)不同坡向沙棘植株进行了距地表0、10、15、20 cm(即a、b、c、d)留茬高度处理,而根系分形特征是植物根系构型应对环境异质性的表型可塑性,为反映沙棘根系对不同坡向不同留茬生长环境的适应...  相似文献   
40.
Environmental Science and Pollution Research - Nitrosamines (NAms) are potent genotoxic and carcinogenic but widely detected in drinking water. This study aimed to investigate the occurrence of...  相似文献   
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