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981.
Impacts on soil invertebrates are an important aspect of environmental risk assessment and post-release monitoring of transgenic insect-resistant plants. The purpose of this study was to research and survey the effects of transgenic insect-resistant cottons that had been planted over 10 years on the abundance and community structure of soil invertebrates under field conditions. During 3 consecutive years (2006-2008), eight common taxa (orders) of soil invertebrates belonging to the phylum Arthropoda were investigated in two different transgenic cotton fields and one non-transgenic cotton field (control). Each year, soil samples were taken at four different growth stages of cotton (seedling, budding, boll forming and boll opening). Animals were extracted from the samples using the improved Tullgren method, counted and determined to the order level. The diversity of the soil fauna communities in the different fields was compared using the Simpson's, Shannon's diversity indices and evenness index. The results showed a significant sampling time variation in the abundance of soil invertebrates monitored in the different fields. However, no difference in soil invertebrate abundance was found between the transgenic cotton fields and the control field. Both sampling time and cotton treatment had a significant effect on the Simpson's, Shannon's diversity indices and evenness index. They were higher in the transgenic fields than the control field at the growth stages of cotton. Long-term cultivation of transgenic insect-resistant cottons had no significant effect on the abundance of soil invertebrates. Collembola, Acarina and Araneae could act as the indicators of soil invertebrate in this region to monitor the environmental impacts of transgenic plants in the future. 相似文献
982.
Lin Wang Wenming Li Puyu Li Minghui Li Shuo Chen Lijun Han 《Environmental monitoring and assessment》2014,186(11):7793-7799
A simple residue analytical method using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for the determination of trifloxystrobin and its metabolite trifloxystrobin acid (CGA321113) in tomato and soil was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of detection were 0.0005 mg/kg for trifloxystrobin and 0.001 mg/kg for trifloxystrobin acid, respectively. The average recoveries in tomato and soil ranged from 73–99 % for trifloxystrobin and 75–109 % for trifloxystrobin acid, with relative standard deviations below 15 %. The method was then used to study the dissipation and residues in tomato and soil. The dissipation half-lives of trifloxystrobin in tomato were 2.9 days (Beijing) and 5.4 days (Shandong), while in soil were 1.9 days (Beijing) and 3.0 days (Shandong), respectively. The final results showed that the major residue compound was trifloxystrobin in tomato whereas it was its metabolite, trifloxystrobin acid, in soil. The final residues of total trifloxystrobin (including trifloxystrobin acid) were below the EU maximum residue limit of 0.5 mg kg?1 in tomato 3 days after the treatment. 相似文献
983.
Kun Lei Xuejiao Han Guo Fu Jian Zhao Libiao Yang 《Environmental monitoring and assessment》2014,186(12):8857-8864
The wide use and occurrence of antibiotics in water environments have caused wide concerns. Ofloxacin (OFL) was selected as a target antibiotic, and the interaction between OFL and sequential extracted dissolved organic matter (DOM) from the sediment of Dianchi, a hypertrophic lake in Southwest China, was explored using fluorescence quenching technology. The method of fuorescence quenching was used to characterize the interaction between OFL and sequentially extracted DOM. The result indicated that static and dynamic quenching both existed in the interaction. The interaction in the background water (0.01 mol/L NaCl and 200 mg/L NaN3) became increasingly weak with the further extraction of DOM. A low non-linear factor N value (0.53~0.63) of Freundlich model was observed, indicating a non-linear interaction between OFL and DOM. Elemental characterization and infrared spectrum analysis showed an enhanced OFL-DOM binding with the decrease in humic acid (HA) polarity. The effect of ion strength was tested in the OFL-DOM interaction to show the impact of usually existing metal ions in water environment on the OFL behavior. The result showed that K+ had little influence, but Cu2+ had a significant promotion (p?0.05) in the OFL-DOM interaction in background water, indicating that divalent metal ions, which have the bridge bond or complexation capacity, are more active in the OFL-DOM interaction than monovalent ions, with no bridge bond or complexation capacity. This work would be useful in the fate and risk assessment of antibiotics in water environments. 相似文献
984.
We consider an environmental–economic game where players face not only Cournot competition but also coupling environmental and individual capacity constraints. Under the complementarity problem framework, we study the existence of the (normalized) Nash equilibrium, computability of the equilibria, and the closed form expressions of the optimal weights. We also report numerical results of two examples as well as the insights gained from them. 相似文献
985.
Qin QZ Chen Y Fu TT Ding L Han LL Li JC 《Environmental monitoring and assessment》2012,184(3):1533-1540
To understand electromagnetic radiation field strength and its influencing factors of certain 110-kV high-voltage lines in
one urban area of Chongqing by measuring 110-kV high-voltage line’s electromagnetic radiation level. According to the methodology
as determined by the National Hygienic Standards, we selected certain adjacent residential buildings, high-voltage lines along
a specific street and selected different distances around its vertical projection point as monitoring points. The levels of
electromagnetic radiations were measured respectively. In this investigation within the frequency of 5–1,000 Hz both the electric
field strength and magnetic field strength of each monitoring sites were lower than the public exposure standards as determined
by the International Commission on Non-Ionizing Radiation Protection. However, the electrical field strength on the roof adjacent
to the high-voltage lines was significantly higher than that as measured on the other floors in the same buildings (p < 0.05). The electromagnetic radiation measurements of different monitoring points, under the same high-voltage lines, showed
the location which is nearer the high-voltage line maintain a consistently higher level of radiation than the more distant
locations (p < 0.05). Electromagnetic radiation generated by high-voltage lines decreases proportionally to the distance from the lines.
The buildings can to some extent shield (or absorb) the electric fields generated by high-voltage lines nearby. The electromagnetic
radiation intensity near high-voltage lines may be mitigated or intensified by the manner in which the high-voltage lines
are set up, and it merits attention for the potential impact on human health. 相似文献
986.
987.
嗅觉标准液是可使人的嗅觉阈值测试标准化,科学化,数量化,应用嗅觉标准液对人群的嗅觉阈值测试,可以了解我国人群嗅觉状及特点,以便应用标准液筛选嗅觉试验员和鼻科临床无创伤检验等方面。 相似文献
988.
Yingruo Li Zhiqiang Ma Tingting Han Weijun Quan Junxia Wang Huaigang Zhou Di He Fan Dong 《环境科学学报(英文版)》2022,34(5):432-442
Carbon monoxide(CO) is primarily the result of incomplete combustion, which has important impacts on the atmospheric chemical cycle and climate. Improved quantitative characterization of long-term CO trends is important for both atmospheric modeling and the design and implementation of policies to efficiently control multiple pollutants. Due to the limitations of high time-resolution and high-quality long-term observational data, studies on long-term trends in the CO concentration in China are q... 相似文献
989.
990.
Xu Han Yuk Shan Wong Ming Hung Wong Nora Fung Yee Tam 《Water environment research》2008,80(7):647-653
The feasibility of obtaining and using the biomass of a microalga, Chlorella miniata, from domestic wastewater (DW) cultures for the removal of chromium(III) [Cr(III)] and chromium(VI) [Cr(VI)] was compared with that from commercial Bristol medium (BM). Results showed that Chlorella miniata cultured in DW under 16-8 hours light-dark cycle [DW(16-8)] had similar growth to that in BM [BM(16-8)], but these two biomass had different biochemical compositions, and the former one had lower carbohydrate and higher protein content. When cultured in domestic wastewater, a higher biomass was obtained under continuous illumination [DW(24-0)], and the cells had higher carbohydrate and lower protein concentrations than that of DW(16-8). The spectra of the Fourier transform infrared spectrometer revealed that the functional groups on the surface of the three kinds of biomass--DW(16-8), DW(24-0), and BM(16-8)--were comparable, except an additional peak at 1731 cm(-1) was found in the biomass cultured in domestic wastewater, which was probably the result of bacterial contamination. Although biochemical differences were found among the three kinds of microalgal biomass, similar biosorption performances to chromium pollutants were recorded, with approximately 75% Cr(III) and 100% Cr(VI) removed at equilibrium in Cr(III) and Cr(VI) experiments, respectively, when dead biomass was used as a biosorbent. Therefore, it is possible to culture Chlorella miniata in domestic wastewater and use the biomass for the removal of chromium pollutants. 相似文献