首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 952 毫秒
1.
污染源限期治理制度,是指人民政府或其所属的环保部门为改善环境质量,对其辖区内的超标排污、已经造成环境严重污染的企业事业单位,及在特殊保护区域内超标排污的非工业生产设施,责令其在一定的期限内治理污染,并由该人民政府所属的环保部门监督其完成治理任务,达到预定治理目标的环境管理制度。这里的“超标”,既指排污浓度超标,也指排污总量指标超标。其法律性质可以概括为:  相似文献   

2.
周新祥 《环境工程》1999,17(2):41-45
通过对LGA风机噪声频谱的测试分析,确认其空气动力性噪声最强。针对其频谱特性,采用动态优化设计方法,设计一种圆盘式消声器。该消声器纵向尺寸小,充分利用其横向空间,结构较简单、紧凑,样式新颖,动态特性好  相似文献   

3.
赵如箱 《交通环保》2000,21(4):15-17
在溢油模型模拟溢油扩散、漂移的轨迹及其归宿的基础上提出溢油反向运算既反推的发展设想,扩展其功能,增加其应用,形成完整的溢油模型,并将该溢油模型运用于海事管理工作中,为海事管理工作服务。  相似文献   

4.
异龙湖流域生态功能区划分析   总被引:2,自引:0,他引:2  
为了改善异龙湖的生态环境,延缓其老化和消亡过程,实现其自然资源的持续利用,以生态学与系统工程学原理为基础,分析异龙湖湖泊生态系统的组成与结构,依据其生态功能分区的原则,将异龙湖流域生态系统划分为4个子系统,分别根据各自的生态功能和主要环境问题,制订有效的保护措施。  相似文献   

5.
本文介绍了陶资多管除尘器的结构,工作原理,影响除尘器性能的因素,阐述了该除尘器的性能特点,同时针对其存在的问题进行优化设计探讨,使其更加完美,更有推广和使用价值。  相似文献   

6.
我国城市固体废弃物资源及其能源潜力   总被引:5,自引:0,他引:5  
我国每年产生的城市固体废弃物达5亿吨之多,其有机成分所占的比例较高;若全部焚烧发电,其能源潜力为1.2×1012度,大约相当于1990年我国发电总量6.2×1011度的两倍;按其所含能量估算,其能源潜力为2.72×1015KJ,相当于9300万吨标准煤,即相当于1981年我国能源消费总量5.5亿吨标准煤的六分之一。  相似文献   

7.
造纸厂水污染分析及治理措施   总被引:1,自引:0,他引:1  
造纸厂水污染严重,排放量大,成份复杂。根据其性质,厂内治理可采用改进生产工艺,综合利用的方式,减轻或消除污染;厂外治理可采取生物或物理化学处理方式削减污染物,使其达标排放。  相似文献   

8.
矿渣污染及其治理   总被引:1,自引:0,他引:1  
矿渣是人为的新的水土流失,环境污染的策源地,对其治理应先工程治理、后生物治理,人工加重其生物演替进程,加快绿化速度、竭止住水土流失,使矿渣造福于当地。  相似文献   

9.
论述了环境保护与经济建设之间协调发展的辩证关系,其目的是如何在市场经济条件下,做好环境保护的法制建设工作,使其在为经济发展保驾护航的同时,不断完善自身的法制建设。  相似文献   

10.
以江苏某化纤厂采集的污泥为对象,应用日本NGK公司提出的污泥分析方法,对其进行理化分析,从干燥速度,组成分析,挥发性有机酸,pH等几个方面进行分析,从而得出其焚烧性能,为后续污泥焚烧工艺提供参考。  相似文献   

11.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

12.
Quantitative information on mass concentrations and other characteristics, such as spatial distribution, seasonal variation, indoor/outdoor (I/O) ratio, correlations and sources, of indoor and outdoor PM2.5 and elemental components in Guangzhou City were provided. Mass concentration of PM2.5 and elemental components were determined by standard weight method and proton-induced X-ray emission (PIXE) method. 18 elements were detected, the results showed positive results. Average indoor and outdoor PM2.5 concentrations in nine sites were in the range of 67.7-74.5μg/m^3 for summer period, and 109.9-123.7 μg/m^3 for winter period, respectively. The sum of 18 elements average concentrations were 5362.6-5533.4 ng/m^3 for summer period, and 8416.8-8900.6 ng/m^3 for winter period, respectively. Average concentrations of PM2.5 and element components showed obvious spatial characteristic, that the concentrations in roadside area and in industrial plant area were higher than those in generic urban area. An obvious seasonal variation characteristic was found for PM2.5 and elemental components, that the concentrations in winter were higher than that in summer. The I/O ratio of PM2.5 and some elemental components presented larger than 1 sometimes. According to indoor/outdoor correlation of PM2.5 and element concentrations, it was found that there were often good relationships between indoor and outdoor concentrations. Enrichment factors were calculated to evaluate anthropogenic versus natural elements sources.  相似文献   

13.
Ecosystem services provided by the landscapes of regions and cities are critical to human and environmental health, quality of life, environmental justice, biodiversity and climate mitigation and adaptation. In the Pacific Northwest region of the US, a team led by the University of Washington Green Futures Lab is working to identify, conserve and enhance regionally-significant landscapes and to evaluate their contributions as ecosystem or “open space” services. This paper outlines the goals and planning methods of the ongoing Regional Open Space Strategy for Central Puget Sound (ROSS) project, and the frameworks and processes being developed to evaluate ecosystem and open space services in order to inform and influence local and regional governance structures and decisions.  相似文献   

14.
综述含钙物质(生石灰(CaO)、熟石灰(Ca (OH)2)及石灰石(CaCO3))对土壤理化性质(pH值、有机质成分及其含量)、土壤微生物群落结构和As赋存形态及生物有效性的影响与机制,及其对植物As吸收积累和As耐性的影响与机制.综述内容可为准确理解含钙物质影响土壤As的生物有效性和植物对As吸收积累的过程机制,进而合理选择含钙物质调控土壤理化性质降低土壤As生物有效性及其生态环境风险提供理论依据和技术参考,对保障土壤种植安全和作物食品安全具有一定现实意义.  相似文献   

15.
The potential for developing synergies between climate change mitigation and adaptation has become a recent focus of both climate research and policy. Presumably the interest in synergies springs from the appeal of creating win–win situations by implementing a single climate policy option. However, institutional complexity, insufficient opportunities and uncertainty surrounding their efficiency and effectiveness present major challenges to the widespread development of synergies. There are also increasing calls for research to define the optimal mix of mitigation and adaptation. These calls are based on the misguided assumption that there is one single optimal mix of adaptation and mitigation options for all possible scenarios of climate and socio-economic change, notwithstanding uncertainty and irrespective of the diversity of values and preferences in society. In the face of current uncertainty, research is needed to provide guidance on how to develop a socially and economically justifiable mix of mitigation, adaptation and development policy, as well as on which elements would be part of such a mix. Moreover, research is needed to establish the conditions under which the process of mainstreaming can be most effective. Rather than actually developing and implementing specific mitigation and adaptation options, the objective of climate policy should be to facilitate such development and implementation as part of sectoral policies. Finally, analysis needs to focus on the optimal use and expected effectiveness of financial instruments, taking into account the mutual effects between these instruments on the one hand, and national and international sectoral investments and official development assistance on the other.  相似文献   

16.
Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.  相似文献   

17.
Biochar is produced from the pyrolysis of carbon-rich plant- and animal-residues under low oxygen and high temperature conditions and has been increasingly used for its positive role in soil compartmentalization through activities such as carbon sequestration and improving soil quality. Biochar is also considered a unique adsorbent due to its high specific surface area and highly carbonaceous nature. Therefore, soil amendments with small amounts of biochar could result in higher adsorption and, consequently, decrease the bioavailability of contaminants to microbial communities, plants, earthworms, and other organisms in the soil. However, the mechanisms affecting the environmental fate and behavior of organic contaminants, especially pesticides in biochar-amended soil, are not well understood. The purpose of this work is to review the role of biochar in primary processes, such as adsorption–desorption and leaching of pesticides. Biochar has demonstrable effects on the fate and effects of pesticides and has been shown to affect the degradation and bioavailability of pesticides for living organisms. Moreover, some key aspects of agricultural and environmental applications of biochar are highlighted.  相似文献   

18.
Massive amounts of pig manure are produced by intensive pig farm in China, and the composition of pig manure has changed much due to the use of feed additives. However, little is known about the exact Cu (copper) feed as additives or present as contaminants in pig feed and the residues in feces. One hundred and thirty-seven feeds and one hundred and forty-two fecal samples from 48 pig farms were collected in Beijing and Fuxin cities in 1999 and 2005, respectively. The concentrations of Cu were in the range of 6.86-395.19 mg/kg in the feed samples, and the mean values were in the order of weaner〉 grower-finisher〉 sow's feeds. The high concentrations over EU recommendations implied that excessive levels of Cu are fed on many pig farms in Beijing and Fuxin. Cu was also present in high concentrations in feces, and concentrations were highly variable. Cu concentrations in the feces from grower-finisher and weaner pigs were significantly greater than feces of sows. The super-intensive and small-scale farms had higher levels of Cu in feces than the middle farms. Cu concentrations in pig feces were approximately 5-times greater than in pig feeds. Feed management in grower-finisher pigs on super-intensive and small-scale pig farms is needed to reduce high Cu concentrations in feces and risks to soil contamination while feces are land-applied.  相似文献   

19.
蔡红  王晓宇  韩辉 《中国环境科学》2020,40(11):4883-4892
为了修复重金属污染土壤,保障蔬菜品质安全,利用产脲酶筛选培养基从重金属污染生菜根际土壤中筛选产脲酶细菌.通过溶液吸附和土壤静置培养试验研究功能菌株对Cd和Pb的固定钝化机制;利用水培试验研究功能菌株对不同品种蔬菜生长及吸收Cd和Pb的影响.结果显示,从生菜根际土壤中共分离到10株产脲酶细菌,其中菌株Microbacterium foliorum CH6和Bacillus thuringiensis N3的产脲酶能力(分别为62.6,59.6mS/(cm·min))和吸附钝化Cd和Pb (84.6%~91.3%)的能力最高.扫描电镜-能谱、傅里叶红外光谱和X衍射分析表明,菌株CH6和N3能够通过细胞壁吸附和诱导重金属成矿反应,降低溶液中的Cd和Pb含量.土壤静置试验表明,与不接种菌株对照相比,菌株CH6和N3均能降低土壤中可交态Cd和Pb (46.3%~66.7%)的含量,增加碳酸盐结合态及残渣态Cd和Pb (40%~95.4%)的含量.砂培试验表明,菌株CH6和N3均能显著降低生菜、上海青和空心菜可食用部分中Cd (39.2%~81.4%)和Pb (27.4%~82.3%)的含量.产脲酶细菌CH6和N3能够矿化土壤中的Cd和Pb,降低土壤中重金属有效态含量,阻控生菜、上海青和空心菜对Cd和Pb的吸收.  相似文献   

20.
产脲酶细菌矿化修复Cd和Pb污染土壤效应和机制   总被引:1,自引:0,他引:1  
蔡红  王晓宇  韩辉 《中国环境科学》2021,40(11):4883-4892
为了修复重金属污染土壤,保障蔬菜品质安全,利用产脲酶筛选培养基从重金属污染生菜根际土壤中筛选产脲酶细菌.通过溶液吸附和土壤静置培养试验研究功能菌株对Cd和Pb的固定钝化机制;利用水培试验研究功能菌株对不同品种蔬菜生长及吸收Cd和Pb的影响.结果显示,从生菜根际土壤中共分离到10株产脲酶细菌,其中菌株Microbacterium foliorum CH6和Bacillus thuringiensis N3的产脲酶能力(分别为62.6,59.6mS/(cm·min))和吸附钝化Cd和Pb (84.6%~91.3%)的能力最高.扫描电镜-能谱、傅里叶红外光谱和X衍射分析表明,菌株CH6和N3能够通过细胞壁吸附和诱导重金属成矿反应,降低溶液中的Cd和Pb含量.土壤静置试验表明,与不接种菌株对照相比,菌株CH6和N3均能降低土壤中可交态Cd和Pb (46.3%~66.7%)的含量,增加碳酸盐结合态及残渣态Cd和Pb (40%~95.4%)的含量.砂培试验表明,菌株CH6和N3均能显著降低生菜、上海青和空心菜可食用部分中Cd (39.2%~81.4%)和Pb (27.4%~82.3%)的含量.产脲酶细菌CH6和N3能够矿化土壤中的Cd和Pb,降低土壤中重金属有效态含量,阻控生菜、上海青和空心菜对Cd和Pb的吸收.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号