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11.
Interaction with nature has a range of significant health, ecological and economic benefits and a number of governments are implementing policies to increase humans’ engagement with nature. Using a large nationally representative survey sample in Australia, this study provides a detailed comment on the feasibility of such a policy, as well as contributing to an understanding of the characteristics of individuals who engaged in one or more of five dimensions of nature interaction, namely: nature engagement; conservation participation; nature advocacy; environmentally friendly purchasing and future engagement with nature conservation. The results indicate that age, income, education, marital status and household structure are all important influences on various types of nature engagement. It is suggested that increasing opportunities for young people to interact with nature is important, as well as supporting older people's involvement in conservation, plus focusing on the need to target and direct various policies.  相似文献   
12.
Environmental Science and Pollution Research - Cypermethrin (CYP) is a toxic manmade chemical compound belonging to pyrethroid insecticides contaminating the environment. Plantago major (PM) has...  相似文献   
13.
The chemical oxygen demand (COD) and NH3-N removal, membrane fouling, sludge characteristics and microbial community structure in a membrane bioreactor (MBR) coupled with worm reactors (SSBWR) were evaluated for 210 days. The obtained results were compared to those from a conventional MBR (C-MBR) operated in parallel. The results indicated that the combined MBR (S-MBR) achieved higher COD and NH3-N removal efficiency, slower increase in membrane fouling, better sludge settleability and higher activities of the related enzymes in the activated sludge. Denaturing gradient gel electrophoresis was used to analyze the microbial community structures in the C-MBR and the S-MBR. The microbial community structure in the S-MBR was more diverse than that in the C-MBR. Additionally, the slow-growing microbes such as Saprospiraceae, Actinomyces, Frankia, Clostridium, Comamonas, Pseudomonas, Dechloromonas and Flavobacterium were enriched in the S-MBR, further accounting for the sludge reduction, membrane fouling alleviation and wastewater treatment.  相似文献   
14.
This study was conducted to assess the effects of difenoconazole (DFZ), a triazole fungicide, on the hepatic biotransformation system and its bioaccumulation in marine medaka (Oryzias melastigma). Fish were exposed to DFZ (1, 10, 100, 1000 ng/L) for 180 days. The results showed that: (1) The mRNA levels of hepatic CYP1A1, CYP1B, CYP1C1, CYP27B and CYP3A40 were up-regulated, but those of CYP3A38 and CYP27A1 were down-regulated. (2) The activity of ethoxyresorufin-O-deethylase (EROD) and the content of reduced glutathione (GSH) in the liver were increased in the DFZ-treated groups, and glutathione S-transferase (GST) activity was increased in the 100 and 1000 ng/L groups. (3) DFZ was accumulated in the muscle and the biological concentration factors in the 10, 100, and 1000 ng/L groups were respectively 149, 81 and 25. These results suggested that long-term exposure to DFZ at low concentrations would result in a bioaccumulation of this compound and disturb the biotransformation system.  相似文献   
15.
The effect of free ammonia on volatile fatty acid(VFA)accumulation and process instability was studied using a lab-scale anaerobic digester fed by two typical bio-wastes:fruit and vegetable waste(FVW)and food waste(FW)at 35°C with an organic loading rate(OLR)of 3.0 kg VS/(m~3·day). The inhibitory effects of free ammonia on methanogenesis were observed due to the low C/N ratio of each substrate(15.6 and 17.2,respectively). A high concentration of free ammonia inhibited methanogenesis resulting in the accumulation of VFAs and a low methane yield. In the inhibited state,acetate accumulated more quickly than propionate and was the main type of accumulated VFA. The co-accumulation of ammonia and VFAs led to an "inhibited steady state" and the ammonia was the main inhibitory substance that triggered the process perturbation. By statistical significance test and VFA fluctuation ratio analysis,the free ammonia inhibition threshold was identified as 45 mg/L. Moreover,propionate,iso-butyrate and valerate were determined to be the three most sensitive VFA parameters that were subject to ammonia inhibition.  相似文献   
16.
Environmental exposure and health risk upon engineered nanomaterials are increasingly concerned. The family of mesoporous carbon nanomaterials(MCNs) is a rising star in nanotechnology for multidisciplinary research with versatile applications in electronics,energy and gas storage, and biomedicine. Meanwhile, there is mounting concern on their environmental health risks due to the growing production and usage of MCNs. The lung is the primary site for particle invasion under environmental exposure to nanomaterials. Here, we studied the comprehensive toxicological profile of MCNs in the lung under the scenario of moderate environmental exposure. It was found that at a low concentration of 10 μg/mL MCNs induced biophysical inhibition of natural pulmonary surfactant. Moreover, MCNs at similar concentrations reduced viability of J774 A.1 macrophages and lung epithelial A549 cells.Incubating with nature pulmonary surfactant effectively reduced the cytotoxicity of MCNs.Regarding the pro-inflammatory responses, MCNs activated macrophages in vitro, and stimulated lung inflammation in mice after inhalation exposure, associated with lung fibrosis.Moreover, we found that the size of MCNs played a significant role in regulating cytotoxicity and pro-inflammatory potential of this nanomaterial. In general, larger MCNs induced more pronounced cytotoxic and pro-inflammatory effects than their smaller counterparts. Our results provided valuable information on the toxicological profile and environmental health risks of MCNs, and suggested that fine-tuning the size of MCNs could be a practical precautionary design strategy to increase safety and biocompatibility of this nanomaterial.  相似文献   
17.
杭州湾表层海水营养盐分布特征及富营养化状况研究   总被引:1,自引:0,他引:1  
根据2015年3月和8月杭州湾的海水质量监测数据,分析了该海域的营养盐分布特征以及富营养化状况,结果表明:杭州湾表层海水无机氮变化范围为0.36~4.22 mg/L,活性磷酸盐的含量范围为0.014~1.51 mg/L,化学需氧量含量范围为0.56~3.18 mg/L.该海域无机氮和活性磷酸盐超标严重,表层海水已处于重度富营养化状态,调查站位EI均大于1.该海域表层海水无机氮、活性磷酸盐、化学需氧量和富营养化指数高值区均与陆源入海口、养殖区、排污口等人类活动影响较大的区域有关.  相似文献   
18.
在省级及以上禁止开发区、重点生态功能保护区等进行调查分析的基础上,以青岛市为实践区域,与多类规划衔接,划定青岛市省级生态保护红线.青岛市最终划定59处省级生态保护红线区,面积合计1120.65 km2,占国土面积的9.9%.划定的生态保护红线符合确立"三生"空间和落实"多规合一"的要求,有利于改善生态系统服务功能,保障人居环境安全,增强经济社会可持续发展能力,对于青岛市市级生态保护红线的划定和生态安全格局的构建具有非常重要的意义.  相似文献   
19.
在GIS和RS支持下,利用土地利用类型数据、地面气象数据和遥感影像数据,以青岛市为例,研究了市域尺度下的植被NPP空间分布特征.结果表明:青岛市NPP值为0~288 g·m-2·a-2,林地NPP值较高,耕地次之,建成区等区域最小.在小尺度区域内,NPP分布受土地利用类型影响较大,受气象因素影响较小.NPP模块在数据获取上比较容易,仅利用土地利用类型数据、地面气象数据和遥感数据就可以对陆地植被NPP进行计算,实际应用可操作性强.30 m分辨率植被NPP计算值更适宜于在市级小尺度区域内应用.  相似文献   
20.
探明污染土壤重金属有效态含量的季节变化特征及其敏感影响因子,对农业生产过程中减低重金属生态风险具有重要的参考价值.研究于湘江中下游典型Cd超标农业小流域中选取稻田、旱作蔬菜地、丘陵林地这3类主要用地类型,分析不同用地类型Cd活性的季节变化特征及其与土壤基本理化参数的关联.为期1 a的原位监测结果显示,研究区为典型酸雨区,雨水p H值呈现冬、春季节低于夏、秋季.稻田土壤总Cd含量显著高于旱作蔬菜地,菜地显著高于林地,3种用地类型土壤总Cd含量季节特征相似,均为夏秋季节略低于冬春两季.3种用地类型Cd有效态季节变化与总Cd含量无明显的相关性,稻田土壤有效态Cd含量在5~9月的作物生长季明显低于其他月份,而菜地和林地则恰好相反.稻田土壤Cd有效性的最关键影响因子为Eh,呈显著正相关,与土壤p H负相关,菜地土壤与土壤TOC明显负相关,而林地土壤Cd有效性与水溶性有机碳、TOC呈现明显的正相关关系.研究可为Cd超标土壤污染阻控与农业安全生产提供一定的数据参考.  相似文献   
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