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791.
As human populations expand and nonhuman animals decline, understanding the interactions between people and wildlife is essential.
For endangered species, appreciating the effect of human disturbance can be important for their conservation. However, a human
disturbance angle is often absent from ecological research, despite growing evidence of the negative impact of nonfatal human
interference. Here, we monitored Hainan Eld’s deer living within a reserve and translocated animals living amongst villagers.
We show that translocated deer deviated from a crepuscular activity pattern and became increasingly nocturnal, and most active
when villagers were not. It appears that translocated deer adapted over time to human disturbance and this pattern is similar
to that of other species during periods of hunting. People do not pose an actual threat to Eld’s deer, but their presence
triggered a response akin to predator avoidance and may be interfering with broader aspects of their biology and conservation. 相似文献
792.
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794.
Luo SL Chen L Chen JL Xiao X Xu TY Wan Y Rao C Liu CB Liu YT Lai C Zeng GM 《Chemosphere》2011,85(7):1130-1138
This study investigates the heavy metal-resistant bacterial endophytes of Cd-hyperaccumulator Solanum nigrum L. grown on a mine tailing by using cultivation-dependent technique. Thirty Cd-tolerant bacterial endophytes were isolated from roots, stems, and leaves of S. nigrum L. and classified by amplified ribosomal DNA-restriction analysis into 18 different types. Phylogenetic analysis based on 16S rDNA sequences showed that these isolates belonged to four groups: Actinobacteria (43%), Proteobacteria (23%), Bacteroidetes (27%) and Firmicutes (7%). All the isolates were then characterized for their plant growth promoting traits as well as their resistances to different heavy metals; and the actual plant growth promotion and colonization ability were also assessed. Four isolates were re-introduced into S. nigrum L. under Cd stress and resulted in Cd phytotoxicity decrease, as dry weights of roots increased from 55% to 143% and dry weights of above-ground from 64% to 100% compared to the uninoculated ones. The total Cd accumulation of inoculated plants increased from 66% to 135% (roots) and from 22% to 64% (above-ground) compared to the uninoculated ones. Our research suggests that bacterial endophytes are a most promising resource and may be the excellent candidates of bio-inoculants for enhancing the phytoremediation efficiency. 相似文献
795.
O3氧化工艺处理黄连素制药废水研究 总被引:1,自引:0,他引:1
采用臭氧(O3)氧化法处理含高浓度黄连素和COD的制药废水,探讨了废水初始pH、O3投加量及初始黄连素浓度等因素对O3氧化过程的影响,确定了O3氧化技术处理黄连素制药废水的最佳操作条件。结果表明,O3能够有效分解废水中的黄连素,降低其COD浓度;黄连素浓度为700mg/L、COD为3500mg/L、pH为0.88的废水,进气O3浓度为14.05mg/(L·min),处理时间为180rain(即投加量为2529mg/L)时,黄连素和COD的降解率分别可达77.46%和41.28%,BOD,/COD比(B/C比)从0.06提高到0.34,增加了4.7倍;随着废水中初始黄连素浓度的升高,废水COD降解率逐渐降低。O3氧化法是一种有效的黄连素制药废水预处理技术,可以大大提高废水的可生化性。 相似文献
796.
气相色谱法测定空气中丙烯酸酯 总被引:6,自引:1,他引:5
讨论了用气相色谱仪测定被污染空气中丙烯酸甲酯、丙烯酸乙酯、甲基丙烯酸甲酯、丙烯酸丁酯的方法条件。方法检出下限在6ng范围,相对标准偏差为14~69%,回收率为906~1105%。实验还显示丙烯酸酯污染空气问题不容忽视。 相似文献
797.
Ground-level ozone in the Pearl River Delta and the roles of VOC and NO(x) in its production 总被引:3,自引:0,他引:3
Shao M Zhang Y Zeng L Tang X Zhang J Zhong L Wang B 《Journal of environmental management》2009,90(1):512-518
In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) emission controls. Nonetheless, ambient NO(2) levels in the Pearl River Delta remained high. The regional average concentrations of volatile organic compounds (VOCs) were 290 ppbC in summer and 190 ppbC in autumn. Local emissions and long-distance transportation of pollutants play important roles in the regional distribution of VOCs. Ambient O(3) production is significant in urban areas and also downwind of cities. The relative incremental reactivities (RIRs), determined by an observation-based model, showed that ground-level ozone formation in the Guangzhou urban area is generally limited by the concentrations of VOCs, but there are also measurable impacts of NO(x). 相似文献
798.
799.
海带对镉的吸附动力学与热力学研究 总被引:7,自引:1,他引:6
采用批量平衡法研究了海带对镉的吸附的动力学与热力学,并采用Lagrange假一级动力学方程、假二级动力学方程、Langmuir等温线方程、Freundlich等温线方程以及Dubimim-Radushkevich等温线方程对实验数据进行了拟合.结果表明,在4种温度下海带对镉的吸附率均随吸附反应时间增加而增大,在60 min时达到最大,此后基本保持不变,随着温度由20℃升高至50℃,其最大吸附率呈下降趋势,由90.2%降至77.5%;海带对镉的吸附动力学符合Lagrange假二级动力学方程;海带对镉的吸附热力学符合Langmuir等温线方程和Dubimim-Radushkevich等温线方程,表明吸附主要发生在海带表面的活性区位,属于单分子层吸附,其吸附平均活化自由能E为11.4 kJ/mol,表明该吸附过程为化学吸附,在4种温度下吉布斯自由能变化量△AG°均为负值,吸附焓变△H°也为负值,表明海带对镉的吸附为放热反应,能自发进行. 相似文献
800.