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101.
Environmental Science and Pollution Research - Coastal ecosystem is vulnerable to heavy metal contamination. The northern Hangzhou Bay is under intensifying impact of anthropogenic activities. To...  相似文献   
102.
Environmental Science and Pollution Research - There is a delayed (lag 1 to 2 days) correlation between acute PM 2.5 (particulate matter <?2.5 μm in aerodynamic...  相似文献   
103.

The Yellow River Delta is the largest and youngest estuarine and coastal wetland in China and is experiencing the most active interactions of seawater and freshwater in the world. Bacteria played multifaceted influence on soil biogeochemical processes, and it was necessary to investigate the intermodulation between the soil factors and bacterial communities. Soil samples were collected at sites with different salinity degree, vegetations, and interference. The sequences of bacilli were tested using 16S rRNA sequencing method and operational taxonomic units were classified with 97% similarity. The soil was highly salinized and oligotrophic, and the wetland was nitrogen-restricted. Redundancy analysis suggested that factors related with seawater erosion were principal to drive the changes of soil bacterial communities and then the nutrient level and human disturbance. A broader implication was that, in the early succession stages of the coastal ecosystem, seawater erosion was the key driver of the variations of marine oligotrophic bacterial communities, while the increasing nutrient availability may enhance in the abundance of the riverine copiotrophs in the late stages. This study provided new insights on the characteristics of soil bacterial communities in estuarine and coastal wetlands.

  相似文献   
104.
本文研究了微量元素Cu2 、Fe2 、Zn2 、Mn2 、Mg2 和PO3-4 对柠檬酸中和废水发酵的影响。在经过“碱沉淀—离子交换法 (AIE法 )”处理后的废水培养基中分别加入 1× 1 0 -8g/mlMn2 、1× 1 0 -7g/mlZn2 、1× 1 0 -6 g/mlMg2 、1× 1 0 -5g/mlCu2 和 1 .5× 1 0 -2 g/mlPO3-4使产酸依次提高 2 .8%、9.0 %、1 0 .5 %、8.3%、7.2 %和 3.4 %。Fe2 的加入降低了柠檬酸产量。  相似文献   
105.
植物抗逆性研究进展   总被引:3,自引:0,他引:3  
本文论述了逆境对植物各方面造成的伤害及植物产生的相应反应 ,重点对植物在生理生化上的变化、对抗性生理领域中的一些学说和最新研究结果作了介绍 ,并指出相生相克现象也可作为抗逆生理的一个方面加以研究 ,概念扩展后的抗逆生理学必将在农业、环保等方面得到更广泛的应用  相似文献   
106.
Environmental Science and Pollution Research - Ionizing radiation (IR) is a form of high energy. It poses a serious threat to organisms, but radiotherapy is a key therapeutic strategy for various...  相似文献   
107.
Environmental Science and Pollution Research - Urban green space is a special space for urban life and natural contact and has an important impact on human health. However, little information is...  相似文献   
108.
Environmental Science and Pollution Research - Coal mine pollution is a serious threat to the mine safe production and occupational health of miners. Chemical dust suppression can effectively...  相似文献   
109.
Compound pollution refers to two or more kinds of pollutants with different properties, a pollutant from different sources, or the simultaneous existence of two or more different types of pollutants in the same environment. In this study, we aimed to investigate the individual and combined toxicity of the insecticide imidacloprid (IMI), the herbicide acetochlor (ACT), and the fungicide tebuconazole (TBZ) to zebrafish. The acute toxicity test results showed that the 96-h LC50 values of IMI, ACT, and TBZ were 276.84 (259.62–294.35) mg active ingredient (a.i.) L−1, 1.52 (1.34–1.74) mg a.i. L−1, and 8.16 (7.7–8.6) mg a.i. L−1, respectively. The combinations of IMI, ACT, and TBZ with toxicity ratios of 1:2:2, 1:4:4, 2:4:1, and 4:1:4 displayed synergistic toxic effects on zebrafish, while the toxicity ratios of 1:1:1, 1:1:2, 2:1:2, 2:2:1, and 4:2:1 of IMI, ACT, and TBZ, respectively, exhibited antagonistic toxic effects on zebrafish. The following experiments were performed with a toxicity ratio of 1:4:4 (IMI:ACT:TBZ). The activities of four enzyme biomarkers related to oxidative stress in the liver, catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and malondialdehyde (MDA) content were evaluated in each exposure group on days 7, 14, 21, and 28. Compared with those of the control group, the activities of CAT, SOD, and GST and the MDA content were significantly altered at different time points in the individual and combined exposure groups. Additionally, the activities of CAT, SOD, and GST and the MDA content were significantly altered in the combined group compared with those of the individual group after 14 days or 21 days of exposure. Therefore, it was confirmed that combined toxicity studies are indispensable in risk assessment.  相似文献   
110.
以某电镀厂水回用系统产生的高盐有机废水为对象,对比研究了Fenton、UV-Fenton等工艺去除COD性能,考察了初始pH、H2O2投加量、Fe2+与H2O2摩尔比、反应时间等参数对处理效果的影响。结果表明:UV-Fenton工艺的最佳条件为初始pH=3.0,H2O2的投加量3 mmol/L,RFe2+:H2O2=1:1,反应时间30 min;在此条件下,COD去除率可达到60%以上,分别较Fenton和UV-H2O2工艺提高23.0%和39.3%。UV-Fenton工艺中,Fenton与UV表现出良好的协同效果,其处理效果较单独Fenton和单独UV处理效果之和高14.7%。UV的引入促进Fe(II)/Fe(Ⅲ)循环,可以提高·OH生成量以及Fe2+与H2O2利用率。UV-Fenton是处理高盐有机废水的可行工艺之一。  相似文献   
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